xref: /third_party/ffmpeg/libswscale/utils.c (revision cabdff1a)
1/*
2 * Copyright (C) 2001-2003 Michael Niedermayer <michaelni@gmx.at>
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21#include "config.h"
22
23#define _DEFAULT_SOURCE
24#define _SVID_SOURCE // needed for MAP_ANONYMOUS
25#define _DARWIN_C_SOURCE // needed for MAP_ANON
26#include <inttypes.h>
27#include <math.h>
28#include <stdio.h>
29#include <string.h>
30#if HAVE_MMAP
31#include <sys/mman.h>
32#if defined(MAP_ANON) && !defined(MAP_ANONYMOUS)
33#define MAP_ANONYMOUS MAP_ANON
34#endif
35#endif
36#if HAVE_VIRTUALALLOC
37#define WIN32_LEAN_AND_MEAN
38#include <windows.h>
39#endif
40
41#include "libavutil/attributes.h"
42#include "libavutil/avassert.h"
43#include "libavutil/cpu.h"
44#include "libavutil/imgutils.h"
45#include "libavutil/intreadwrite.h"
46#include "libavutil/libm.h"
47#include "libavutil/mathematics.h"
48#include "libavutil/opt.h"
49#include "libavutil/pixdesc.h"
50#include "libavutil/slicethread.h"
51#include "libavutil/thread.h"
52#include "libavutil/aarch64/cpu.h"
53#include "libavutil/ppc/cpu.h"
54#include "libavutil/x86/asm.h"
55#include "libavutil/x86/cpu.h"
56
57#include "rgb2rgb.h"
58#include "swscale.h"
59#include "swscale_internal.h"
60
61static SwsVector *sws_getIdentityVec(void);
62static void sws_addVec(SwsVector *a, SwsVector *b);
63static void sws_shiftVec(SwsVector *a, int shift);
64static void sws_printVec2(SwsVector *a, AVClass *log_ctx, int log_level);
65
66static void handle_formats(SwsContext *c);
67
68typedef struct FormatEntry {
69    uint8_t is_supported_in         :1;
70    uint8_t is_supported_out        :1;
71    uint8_t is_supported_endianness :1;
72} FormatEntry;
73
74static const FormatEntry format_entries[] = {
75    [AV_PIX_FMT_YUV420P]     = { 1, 1 },
76    [AV_PIX_FMT_YUYV422]     = { 1, 1 },
77    [AV_PIX_FMT_RGB24]       = { 1, 1 },
78    [AV_PIX_FMT_BGR24]       = { 1, 1 },
79    [AV_PIX_FMT_YUV422P]     = { 1, 1 },
80    [AV_PIX_FMT_YUV444P]     = { 1, 1 },
81    [AV_PIX_FMT_YUV410P]     = { 1, 1 },
82    [AV_PIX_FMT_YUV411P]     = { 1, 1 },
83    [AV_PIX_FMT_GRAY8]       = { 1, 1 },
84    [AV_PIX_FMT_MONOWHITE]   = { 1, 1 },
85    [AV_PIX_FMT_MONOBLACK]   = { 1, 1 },
86    [AV_PIX_FMT_PAL8]        = { 1, 0 },
87    [AV_PIX_FMT_YUVJ420P]    = { 1, 1 },
88    [AV_PIX_FMT_YUVJ411P]    = { 1, 1 },
89    [AV_PIX_FMT_YUVJ422P]    = { 1, 1 },
90    [AV_PIX_FMT_YUVJ444P]    = { 1, 1 },
91    [AV_PIX_FMT_YVYU422]     = { 1, 1 },
92    [AV_PIX_FMT_UYVY422]     = { 1, 1 },
93    [AV_PIX_FMT_UYYVYY411]   = { 0, 0 },
94    [AV_PIX_FMT_BGR8]        = { 1, 1 },
95    [AV_PIX_FMT_BGR4]        = { 0, 1 },
96    [AV_PIX_FMT_BGR4_BYTE]   = { 1, 1 },
97    [AV_PIX_FMT_RGB8]        = { 1, 1 },
98    [AV_PIX_FMT_RGB4]        = { 0, 1 },
99    [AV_PIX_FMT_RGB4_BYTE]   = { 1, 1 },
100    [AV_PIX_FMT_NV12]        = { 1, 1 },
101    [AV_PIX_FMT_NV21]        = { 1, 1 },
102    [AV_PIX_FMT_ARGB]        = { 1, 1 },
103    [AV_PIX_FMT_RGBA]        = { 1, 1 },
104    [AV_PIX_FMT_ABGR]        = { 1, 1 },
105    [AV_PIX_FMT_BGRA]        = { 1, 1 },
106    [AV_PIX_FMT_0RGB]        = { 1, 1 },
107    [AV_PIX_FMT_RGB0]        = { 1, 1 },
108    [AV_PIX_FMT_0BGR]        = { 1, 1 },
109    [AV_PIX_FMT_BGR0]        = { 1, 1 },
110    [AV_PIX_FMT_GRAY9BE]     = { 1, 1 },
111    [AV_PIX_FMT_GRAY9LE]     = { 1, 1 },
112    [AV_PIX_FMT_GRAY10BE]    = { 1, 1 },
113    [AV_PIX_FMT_GRAY10LE]    = { 1, 1 },
114    [AV_PIX_FMT_GRAY12BE]    = { 1, 1 },
115    [AV_PIX_FMT_GRAY12LE]    = { 1, 1 },
116    [AV_PIX_FMT_GRAY14BE]    = { 1, 1 },
117    [AV_PIX_FMT_GRAY14LE]    = { 1, 1 },
118    [AV_PIX_FMT_GRAY16BE]    = { 1, 1 },
119    [AV_PIX_FMT_GRAY16LE]    = { 1, 1 },
120    [AV_PIX_FMT_YUV440P]     = { 1, 1 },
121    [AV_PIX_FMT_YUVJ440P]    = { 1, 1 },
122    [AV_PIX_FMT_YUV440P10LE] = { 1, 1 },
123    [AV_PIX_FMT_YUV440P10BE] = { 1, 1 },
124    [AV_PIX_FMT_YUV440P12LE] = { 1, 1 },
125    [AV_PIX_FMT_YUV440P12BE] = { 1, 1 },
126    [AV_PIX_FMT_YUVA420P]    = { 1, 1 },
127    [AV_PIX_FMT_YUVA422P]    = { 1, 1 },
128    [AV_PIX_FMT_YUVA444P]    = { 1, 1 },
129    [AV_PIX_FMT_YUVA420P9BE] = { 1, 1 },
130    [AV_PIX_FMT_YUVA420P9LE] = { 1, 1 },
131    [AV_PIX_FMT_YUVA422P9BE] = { 1, 1 },
132    [AV_PIX_FMT_YUVA422P9LE] = { 1, 1 },
133    [AV_PIX_FMT_YUVA444P9BE] = { 1, 1 },
134    [AV_PIX_FMT_YUVA444P9LE] = { 1, 1 },
135    [AV_PIX_FMT_YUVA420P10BE]= { 1, 1 },
136    [AV_PIX_FMT_YUVA420P10LE]= { 1, 1 },
137    [AV_PIX_FMT_YUVA422P10BE]= { 1, 1 },
138    [AV_PIX_FMT_YUVA422P10LE]= { 1, 1 },
139    [AV_PIX_FMT_YUVA444P10BE]= { 1, 1 },
140    [AV_PIX_FMT_YUVA444P10LE]= { 1, 1 },
141    [AV_PIX_FMT_YUVA420P16BE]= { 1, 1 },
142    [AV_PIX_FMT_YUVA420P16LE]= { 1, 1 },
143    [AV_PIX_FMT_YUVA422P16BE]= { 1, 1 },
144    [AV_PIX_FMT_YUVA422P16LE]= { 1, 1 },
145    [AV_PIX_FMT_YUVA444P16BE]= { 1, 1 },
146    [AV_PIX_FMT_YUVA444P16LE]= { 1, 1 },
147    [AV_PIX_FMT_RGB48BE]     = { 1, 1 },
148    [AV_PIX_FMT_RGB48LE]     = { 1, 1 },
149    [AV_PIX_FMT_RGBA64BE]    = { 1, 1, 1 },
150    [AV_PIX_FMT_RGBA64LE]    = { 1, 1, 1 },
151    [AV_PIX_FMT_RGB565BE]    = { 1, 1 },
152    [AV_PIX_FMT_RGB565LE]    = { 1, 1 },
153    [AV_PIX_FMT_RGB555BE]    = { 1, 1 },
154    [AV_PIX_FMT_RGB555LE]    = { 1, 1 },
155    [AV_PIX_FMT_BGR565BE]    = { 1, 1 },
156    [AV_PIX_FMT_BGR565LE]    = { 1, 1 },
157    [AV_PIX_FMT_BGR555BE]    = { 1, 1 },
158    [AV_PIX_FMT_BGR555LE]    = { 1, 1 },
159    [AV_PIX_FMT_YUV420P16LE] = { 1, 1 },
160    [AV_PIX_FMT_YUV420P16BE] = { 1, 1 },
161    [AV_PIX_FMT_YUV422P16LE] = { 1, 1 },
162    [AV_PIX_FMT_YUV422P16BE] = { 1, 1 },
163    [AV_PIX_FMT_YUV444P16LE] = { 1, 1 },
164    [AV_PIX_FMT_YUV444P16BE] = { 1, 1 },
165    [AV_PIX_FMT_RGB444LE]    = { 1, 1 },
166    [AV_PIX_FMT_RGB444BE]    = { 1, 1 },
167    [AV_PIX_FMT_BGR444LE]    = { 1, 1 },
168    [AV_PIX_FMT_BGR444BE]    = { 1, 1 },
169    [AV_PIX_FMT_YA8]         = { 1, 1 },
170    [AV_PIX_FMT_YA16BE]      = { 1, 1 },
171    [AV_PIX_FMT_YA16LE]      = { 1, 1 },
172    [AV_PIX_FMT_BGR48BE]     = { 1, 1 },
173    [AV_PIX_FMT_BGR48LE]     = { 1, 1 },
174    [AV_PIX_FMT_BGRA64BE]    = { 1, 1, 1 },
175    [AV_PIX_FMT_BGRA64LE]    = { 1, 1, 1 },
176    [AV_PIX_FMT_YUV420P9BE]  = { 1, 1 },
177    [AV_PIX_FMT_YUV420P9LE]  = { 1, 1 },
178    [AV_PIX_FMT_YUV420P10BE] = { 1, 1 },
179    [AV_PIX_FMT_YUV420P10LE] = { 1, 1 },
180    [AV_PIX_FMT_YUV420P12BE] = { 1, 1 },
181    [AV_PIX_FMT_YUV420P12LE] = { 1, 1 },
182    [AV_PIX_FMT_YUV420P14BE] = { 1, 1 },
183    [AV_PIX_FMT_YUV420P14LE] = { 1, 1 },
184    [AV_PIX_FMT_YUV422P9BE]  = { 1, 1 },
185    [AV_PIX_FMT_YUV422P9LE]  = { 1, 1 },
186    [AV_PIX_FMT_YUV422P10BE] = { 1, 1 },
187    [AV_PIX_FMT_YUV422P10LE] = { 1, 1 },
188    [AV_PIX_FMT_YUV422P12BE] = { 1, 1 },
189    [AV_PIX_FMT_YUV422P12LE] = { 1, 1 },
190    [AV_PIX_FMT_YUV422P14BE] = { 1, 1 },
191    [AV_PIX_FMT_YUV422P14LE] = { 1, 1 },
192    [AV_PIX_FMT_YUV444P9BE]  = { 1, 1 },
193    [AV_PIX_FMT_YUV444P9LE]  = { 1, 1 },
194    [AV_PIX_FMT_YUV444P10BE] = { 1, 1 },
195    [AV_PIX_FMT_YUV444P10LE] = { 1, 1 },
196    [AV_PIX_FMT_YUV444P12BE] = { 1, 1 },
197    [AV_PIX_FMT_YUV444P12LE] = { 1, 1 },
198    [AV_PIX_FMT_YUV444P14BE] = { 1, 1 },
199    [AV_PIX_FMT_YUV444P14LE] = { 1, 1 },
200    [AV_PIX_FMT_GBRP]        = { 1, 1 },
201    [AV_PIX_FMT_GBRP9LE]     = { 1, 1 },
202    [AV_PIX_FMT_GBRP9BE]     = { 1, 1 },
203    [AV_PIX_FMT_GBRP10LE]    = { 1, 1 },
204    [AV_PIX_FMT_GBRP10BE]    = { 1, 1 },
205    [AV_PIX_FMT_GBRAP10LE]   = { 1, 1 },
206    [AV_PIX_FMT_GBRAP10BE]   = { 1, 1 },
207    [AV_PIX_FMT_GBRP12LE]    = { 1, 1 },
208    [AV_PIX_FMT_GBRP12BE]    = { 1, 1 },
209    [AV_PIX_FMT_GBRAP12LE]   = { 1, 1 },
210    [AV_PIX_FMT_GBRAP12BE]   = { 1, 1 },
211    [AV_PIX_FMT_GBRP14LE]    = { 1, 1 },
212    [AV_PIX_FMT_GBRP14BE]    = { 1, 1 },
213    [AV_PIX_FMT_GBRP16LE]    = { 1, 1 },
214    [AV_PIX_FMT_GBRP16BE]    = { 1, 1 },
215    [AV_PIX_FMT_GBRPF32LE]   = { 1, 1 },
216    [AV_PIX_FMT_GBRPF32BE]   = { 1, 1 },
217    [AV_PIX_FMT_GBRAPF32LE]  = { 1, 1 },
218    [AV_PIX_FMT_GBRAPF32BE]  = { 1, 1 },
219    [AV_PIX_FMT_GBRAP]       = { 1, 1 },
220    [AV_PIX_FMT_GBRAP16LE]   = { 1, 1 },
221    [AV_PIX_FMT_GBRAP16BE]   = { 1, 1 },
222    [AV_PIX_FMT_BAYER_BGGR8] = { 1, 0 },
223    [AV_PIX_FMT_BAYER_RGGB8] = { 1, 0 },
224    [AV_PIX_FMT_BAYER_GBRG8] = { 1, 0 },
225    [AV_PIX_FMT_BAYER_GRBG8] = { 1, 0 },
226    [AV_PIX_FMT_BAYER_BGGR16LE] = { 1, 0 },
227    [AV_PIX_FMT_BAYER_BGGR16BE] = { 1, 0 },
228    [AV_PIX_FMT_BAYER_RGGB16LE] = { 1, 0 },
229    [AV_PIX_FMT_BAYER_RGGB16BE] = { 1, 0 },
230    [AV_PIX_FMT_BAYER_GBRG16LE] = { 1, 0 },
231    [AV_PIX_FMT_BAYER_GBRG16BE] = { 1, 0 },
232    [AV_PIX_FMT_BAYER_GRBG16LE] = { 1, 0 },
233    [AV_PIX_FMT_BAYER_GRBG16BE] = { 1, 0 },
234    [AV_PIX_FMT_XYZ12BE]     = { 1, 1, 1 },
235    [AV_PIX_FMT_XYZ12LE]     = { 1, 1, 1 },
236    [AV_PIX_FMT_AYUV64LE]    = { 1, 1},
237    [AV_PIX_FMT_P010LE]      = { 1, 1 },
238    [AV_PIX_FMT_P010BE]      = { 1, 1 },
239    [AV_PIX_FMT_P016LE]      = { 1, 1 },
240    [AV_PIX_FMT_P016BE]      = { 1, 1 },
241    [AV_PIX_FMT_GRAYF32LE]   = { 1, 1 },
242    [AV_PIX_FMT_GRAYF32BE]   = { 1, 1 },
243    [AV_PIX_FMT_YUVA422P12BE] = { 1, 1 },
244    [AV_PIX_FMT_YUVA422P12LE] = { 1, 1 },
245    [AV_PIX_FMT_YUVA444P12BE] = { 1, 1 },
246    [AV_PIX_FMT_YUVA444P12LE] = { 1, 1 },
247    [AV_PIX_FMT_NV24]        = { 1, 1 },
248    [AV_PIX_FMT_NV42]        = { 1, 1 },
249    [AV_PIX_FMT_Y210LE]      = { 1, 0 },
250    [AV_PIX_FMT_X2RGB10LE]   = { 1, 1 },
251    [AV_PIX_FMT_X2BGR10LE]   = { 1, 1 },
252    [AV_PIX_FMT_P210BE]      = { 1, 1 },
253    [AV_PIX_FMT_P210LE]      = { 1, 1 },
254    [AV_PIX_FMT_P410BE]      = { 1, 1 },
255    [AV_PIX_FMT_P410LE]      = { 1, 1 },
256    [AV_PIX_FMT_P216BE]      = { 1, 1 },
257    [AV_PIX_FMT_P216LE]      = { 1, 1 },
258    [AV_PIX_FMT_P416BE]      = { 1, 1 },
259    [AV_PIX_FMT_P416LE]      = { 1, 1 },
260};
261
262int ff_shuffle_filter_coefficients(SwsContext *c, int *filterPos,
263                                   int filterSize, int16_t *filter,
264                                   int dstW)
265{
266#if ARCH_X86_64
267    int i, j, k;
268    int cpu_flags = av_get_cpu_flags();
269    // avx2 hscale filter processes 16 pixel blocks.
270    if (!filter || dstW % 16 != 0)
271        return 0;
272    if (EXTERNAL_AVX2_FAST(cpu_flags) && !(cpu_flags & AV_CPU_FLAG_SLOW_GATHER)) {
273        if ((c->srcBpc == 8) && (c->dstBpc <= 14)) {
274           int16_t *filterCopy = NULL;
275           if (filterSize > 4) {
276               if (!FF_ALLOC_TYPED_ARRAY(filterCopy, dstW * filterSize))
277                   return AVERROR(ENOMEM);
278               memcpy(filterCopy, filter, dstW * filterSize * sizeof(int16_t));
279           }
280           // Do not swap filterPos for pixels which won't be processed by
281           // the main loop.
282           for (i = 0; i + 8 <= dstW; i += 8) {
283               FFSWAP(int, filterPos[i + 2], filterPos[i + 4]);
284               FFSWAP(int, filterPos[i + 3], filterPos[i + 5]);
285           }
286           if (filterSize > 4) {
287               // 16 pixels are processed at a time.
288               for (i = 0; i + 16 <= dstW; i += 16) {
289                   // 4 filter coeffs are processed at a time.
290                   for (k = 0; k + 4 <= filterSize; k += 4) {
291                       for (j = 0; j < 16; ++j) {
292                           int from = (i + j) * filterSize + k;
293                           int to = i * filterSize + j * 4 + k * 16;
294                           memcpy(&filter[to], &filterCopy[from], 4 * sizeof(int16_t));
295                       }
296                   }
297               }
298           }
299           av_free(filterCopy);
300        }
301    }
302#endif
303    return 0;
304}
305
306int sws_isSupportedInput(enum AVPixelFormat pix_fmt)
307{
308    return (unsigned)pix_fmt < FF_ARRAY_ELEMS(format_entries) ?
309           format_entries[pix_fmt].is_supported_in : 0;
310}
311
312int sws_isSupportedOutput(enum AVPixelFormat pix_fmt)
313{
314    return (unsigned)pix_fmt < FF_ARRAY_ELEMS(format_entries) ?
315           format_entries[pix_fmt].is_supported_out : 0;
316}
317
318int sws_isSupportedEndiannessConversion(enum AVPixelFormat pix_fmt)
319{
320    return (unsigned)pix_fmt < FF_ARRAY_ELEMS(format_entries) ?
321           format_entries[pix_fmt].is_supported_endianness : 0;
322}
323
324static double getSplineCoeff(double a, double b, double c, double d,
325                             double dist)
326{
327    if (dist <= 1.0)
328        return ((d * dist + c) * dist + b) * dist + a;
329    else
330        return getSplineCoeff(0.0,
331                               b + 2.0 * c + 3.0 * d,
332                               c + 3.0 * d,
333                              -b - 3.0 * c - 6.0 * d,
334                              dist - 1.0);
335}
336
337static av_cold int get_local_pos(SwsContext *s, int chr_subsample, int pos, int dir)
338{
339    if (pos == -1 || pos <= -513) {
340        pos = (128 << chr_subsample) - 128;
341    }
342    pos += 128; // relative to ideal left edge
343    return pos >> chr_subsample;
344}
345
346typedef struct {
347    int flag;                   ///< flag associated to the algorithm
348    const char *description;    ///< human-readable description
349    int size_factor;            ///< size factor used when initing the filters
350} ScaleAlgorithm;
351
352static const ScaleAlgorithm scale_algorithms[] = {
353    { SWS_AREA,          "area averaging",                  1 /* downscale only, for upscale it is bilinear */ },
354    { SWS_BICUBIC,       "bicubic",                         4 },
355    { SWS_BICUBLIN,      "luma bicubic / chroma bilinear", -1 },
356    { SWS_BILINEAR,      "bilinear",                        2 },
357    { SWS_FAST_BILINEAR, "fast bilinear",                  -1 },
358    { SWS_GAUSS,         "Gaussian",                        8 /* infinite ;) */ },
359    { SWS_LANCZOS,       "Lanczos",                        -1 /* custom */ },
360    { SWS_POINT,         "nearest neighbor / point",       -1 },
361    { SWS_SINC,          "sinc",                           20 /* infinite ;) */ },
362    { SWS_SPLINE,        "bicubic spline",                 20 /* infinite :)*/ },
363    { SWS_X,             "experimental",                    8 },
364};
365
366static av_cold int initFilter(int16_t **outFilter, int32_t **filterPos,
367                              int *outFilterSize, int xInc, int srcW,
368                              int dstW, int filterAlign, int one,
369                              int flags, int cpu_flags,
370                              SwsVector *srcFilter, SwsVector *dstFilter,
371                              double param[2], int srcPos, int dstPos)
372{
373    int i;
374    int filterSize;
375    int filter2Size;
376    int minFilterSize;
377    int64_t *filter    = NULL;
378    int64_t *filter2   = NULL;
379    const int64_t fone = 1LL << (54 - FFMIN(av_log2(srcW/dstW), 8));
380    int ret            = -1;
381
382    emms_c(); // FIXME should not be required but IS (even for non-MMX versions)
383
384    // NOTE: the +3 is for the MMX(+1) / SSE(+3) scaler which reads over the end
385    if (!FF_ALLOC_TYPED_ARRAY(*filterPos, dstW + 3))
386        goto nomem;
387
388    if (FFABS(xInc - 0x10000) < 10 && srcPos == dstPos) { // unscaled
389        int i;
390        filterSize = 1;
391        if (!FF_ALLOCZ_TYPED_ARRAY(filter, dstW * filterSize))
392            goto nomem;
393
394        for (i = 0; i < dstW; i++) {
395            filter[i * filterSize] = fone;
396            (*filterPos)[i]        = i;
397        }
398    } else if (flags & SWS_POINT) { // lame looking point sampling mode
399        int i;
400        int64_t xDstInSrc;
401        filterSize = 1;
402        if (!FF_ALLOC_TYPED_ARRAY(filter, dstW * filterSize))
403            goto nomem;
404
405        xDstInSrc = ((dstPos*(int64_t)xInc)>>8) - ((srcPos*0x8000LL)>>7);
406        for (i = 0; i < dstW; i++) {
407            int xx = (xDstInSrc - ((filterSize - 1) << 15) + (1 << 15)) >> 16;
408
409            (*filterPos)[i] = xx;
410            filter[i]       = fone;
411            xDstInSrc      += xInc;
412        }
413    } else if ((xInc <= (1 << 16) && (flags & SWS_AREA)) ||
414               (flags & SWS_FAST_BILINEAR)) { // bilinear upscale
415        int i;
416        int64_t xDstInSrc;
417        filterSize = 2;
418        if (!FF_ALLOC_TYPED_ARRAY(filter, dstW * filterSize))
419            goto nomem;
420
421        xDstInSrc = ((dstPos*(int64_t)xInc)>>8) - ((srcPos*0x8000LL)>>7);
422        for (i = 0; i < dstW; i++) {
423            int xx = (xDstInSrc - ((filterSize - 1) << 15) + (1 << 15)) >> 16;
424            int j;
425
426            (*filterPos)[i] = xx;
427            // bilinear upscale / linear interpolate / area averaging
428            for (j = 0; j < filterSize; j++) {
429                int64_t coeff = fone - FFABS((int64_t)xx * (1 << 16) - xDstInSrc) * (fone >> 16);
430                if (coeff < 0)
431                    coeff = 0;
432                filter[i * filterSize + j] = coeff;
433                xx++;
434            }
435            xDstInSrc += xInc;
436        }
437    } else {
438        int64_t xDstInSrc;
439        int sizeFactor = -1;
440
441        for (i = 0; i < FF_ARRAY_ELEMS(scale_algorithms); i++) {
442            if (flags & scale_algorithms[i].flag && scale_algorithms[i].size_factor > 0) {
443                sizeFactor = scale_algorithms[i].size_factor;
444                break;
445            }
446        }
447        if (flags & SWS_LANCZOS)
448            sizeFactor = param[0] != SWS_PARAM_DEFAULT ? ceil(2 * param[0]) : 6;
449        av_assert0(sizeFactor > 0);
450
451        if (xInc <= 1 << 16)
452            filterSize = 1 + sizeFactor;    // upscale
453        else
454            filterSize = 1 + (sizeFactor * srcW + dstW - 1) / dstW;
455
456        filterSize = FFMIN(filterSize, srcW - 2);
457        filterSize = FFMAX(filterSize, 1);
458
459        if (!FF_ALLOC_TYPED_ARRAY(filter, dstW * filterSize))
460            goto nomem;
461        xDstInSrc = ((dstPos*(int64_t)xInc)>>7) - ((srcPos*0x10000LL)>>7);
462        for (i = 0; i < dstW; i++) {
463            int xx = (xDstInSrc - (filterSize - 2) * (1LL<<16)) / (1 << 17);
464            int j;
465            (*filterPos)[i] = xx;
466            for (j = 0; j < filterSize; j++) {
467                int64_t d = (FFABS(((int64_t)xx * (1 << 17)) - xDstInSrc)) << 13;
468                double floatd;
469                int64_t coeff;
470
471                if (xInc > 1 << 16)
472                    d = d * dstW / srcW;
473                floatd = d * (1.0 / (1 << 30));
474
475                if (flags & SWS_BICUBIC) {
476                    int64_t B = (param[0] != SWS_PARAM_DEFAULT ? param[0] :   0) * (1 << 24);
477                    int64_t C = (param[1] != SWS_PARAM_DEFAULT ? param[1] : 0.6) * (1 << 24);
478
479                    if (d >= 1LL << 31) {
480                        coeff = 0.0;
481                    } else {
482                        int64_t dd  = (d  * d) >> 30;
483                        int64_t ddd = (dd * d) >> 30;
484
485                        if (d < 1LL << 30)
486                            coeff =  (12 * (1 << 24) -  9 * B - 6 * C) * ddd +
487                                    (-18 * (1 << 24) + 12 * B + 6 * C) *  dd +
488                                      (6 * (1 << 24) -  2 * B)         * (1 << 30);
489                        else
490                            coeff =      (-B -  6 * C) * ddd +
491                                      (6 * B + 30 * C) * dd  +
492                                    (-12 * B - 48 * C) * d   +
493                                      (8 * B + 24 * C) * (1 << 30);
494                    }
495                    coeff /= (1LL<<54)/fone;
496                } else if (flags & SWS_X) {
497                    double A = param[0] != SWS_PARAM_DEFAULT ? param[0] : 1.0;
498                    double c;
499
500                    if (floatd < 1.0)
501                        c = cos(floatd * M_PI);
502                    else
503                        c = -1.0;
504                    if (c < 0.0)
505                        c = -pow(-c, A);
506                    else
507                        c = pow(c, A);
508                    coeff = (c * 0.5 + 0.5) * fone;
509                } else if (flags & SWS_AREA) {
510                    int64_t d2 = d - (1 << 29);
511                    if (d2 * xInc < -(1LL << (29 + 16)))
512                        coeff = 1.0 * (1LL << (30 + 16));
513                    else if (d2 * xInc < (1LL << (29 + 16)))
514                        coeff = -d2 * xInc + (1LL << (29 + 16));
515                    else
516                        coeff = 0.0;
517                    coeff *= fone >> (30 + 16);
518                } else if (flags & SWS_GAUSS) {
519                    double p = param[0] != SWS_PARAM_DEFAULT ? param[0] : 3.0;
520                    coeff = exp2(-p * floatd * floatd) * fone;
521                } else if (flags & SWS_SINC) {
522                    coeff = (d ? sin(floatd * M_PI) / (floatd * M_PI) : 1.0) * fone;
523                } else if (flags & SWS_LANCZOS) {
524                    double p = param[0] != SWS_PARAM_DEFAULT ? param[0] : 3.0;
525                    coeff = (d ? sin(floatd * M_PI) * sin(floatd * M_PI / p) /
526                             (floatd * floatd * M_PI * M_PI / p) : 1.0) * fone;
527                    if (floatd > p)
528                        coeff = 0;
529                } else if (flags & SWS_BILINEAR) {
530                    coeff = (1 << 30) - d;
531                    if (coeff < 0)
532                        coeff = 0;
533                    coeff *= fone >> 30;
534                } else if (flags & SWS_SPLINE) {
535                    double p = -2.196152422706632;
536                    coeff = getSplineCoeff(1.0, 0.0, p, -p - 1.0, floatd) * fone;
537                } else {
538                    av_assert0(0);
539                }
540
541                filter[i * filterSize + j] = coeff;
542                xx++;
543            }
544            xDstInSrc += 2 * xInc;
545        }
546    }
547
548    /* apply src & dst Filter to filter -> filter2
549     * av_free(filter);
550     */
551    av_assert0(filterSize > 0);
552    filter2Size = filterSize;
553    if (srcFilter)
554        filter2Size += srcFilter->length - 1;
555    if (dstFilter)
556        filter2Size += dstFilter->length - 1;
557    av_assert0(filter2Size > 0);
558    if (!FF_ALLOCZ_TYPED_ARRAY(filter2, dstW * filter2Size))
559        goto nomem;
560    for (i = 0; i < dstW; i++) {
561        int j, k;
562
563        if (srcFilter) {
564            for (k = 0; k < srcFilter->length; k++) {
565                for (j = 0; j < filterSize; j++)
566                    filter2[i * filter2Size + k + j] +=
567                        srcFilter->coeff[k] * filter[i * filterSize + j];
568            }
569        } else {
570            for (j = 0; j < filterSize; j++)
571                filter2[i * filter2Size + j] = filter[i * filterSize + j];
572        }
573        // FIXME dstFilter
574
575        (*filterPos)[i] += (filterSize - 1) / 2 - (filter2Size - 1) / 2;
576    }
577    av_freep(&filter);
578
579    /* try to reduce the filter-size (step1 find size and shift left) */
580    // Assume it is near normalized (*0.5 or *2.0 is OK but * 0.001 is not).
581    minFilterSize = 0;
582    for (i = dstW - 1; i >= 0; i--) {
583        int min = filter2Size;
584        int j;
585        int64_t cutOff = 0.0;
586
587        /* get rid of near zero elements on the left by shifting left */
588        for (j = 0; j < filter2Size; j++) {
589            int k;
590            cutOff += FFABS(filter2[i * filter2Size]);
591
592            if (cutOff > SWS_MAX_REDUCE_CUTOFF * fone)
593                break;
594
595            /* preserve monotonicity because the core can't handle the
596             * filter otherwise */
597            if (i < dstW - 1 && (*filterPos)[i] >= (*filterPos)[i + 1])
598                break;
599
600            // move filter coefficients left
601            for (k = 1; k < filter2Size; k++)
602                filter2[i * filter2Size + k - 1] = filter2[i * filter2Size + k];
603            filter2[i * filter2Size + k - 1] = 0;
604            (*filterPos)[i]++;
605        }
606
607        cutOff = 0;
608        /* count near zeros on the right */
609        for (j = filter2Size - 1; j > 0; j--) {
610            cutOff += FFABS(filter2[i * filter2Size + j]);
611
612            if (cutOff > SWS_MAX_REDUCE_CUTOFF * fone)
613                break;
614            min--;
615        }
616
617        if (min > minFilterSize)
618            minFilterSize = min;
619    }
620
621    if (PPC_ALTIVEC(cpu_flags)) {
622        // we can handle the special case 4, so we don't want to go the full 8
623        if (minFilterSize < 5)
624            filterAlign = 4;
625
626        /* We really don't want to waste our time doing useless computation, so
627         * fall back on the scalar C code for very small filters.
628         * Vectorizing is worth it only if you have a decent-sized vector. */
629        if (minFilterSize < 3)
630            filterAlign = 1;
631    }
632
633    if (HAVE_MMX && cpu_flags & AV_CPU_FLAG_MMX) {
634        // special case for unscaled vertical filtering
635        if (minFilterSize == 1 && filterAlign == 2)
636            filterAlign = 1;
637    }
638
639    av_assert0(minFilterSize > 0);
640    filterSize = (minFilterSize + (filterAlign - 1)) & (~(filterAlign - 1));
641    av_assert0(filterSize > 0);
642    filter = av_malloc_array(dstW, filterSize * sizeof(*filter));
643    if (!filter)
644        goto nomem;
645    if (filterSize >= MAX_FILTER_SIZE * 16 /
646                      ((flags & SWS_ACCURATE_RND) ? APCK_SIZE : 16)) {
647        ret = RETCODE_USE_CASCADE;
648        goto fail;
649    }
650    *outFilterSize = filterSize;
651
652    if (flags & SWS_PRINT_INFO)
653        av_log(NULL, AV_LOG_VERBOSE,
654               "SwScaler: reducing / aligning filtersize %d -> %d\n",
655               filter2Size, filterSize);
656    /* try to reduce the filter-size (step2 reduce it) */
657    for (i = 0; i < dstW; i++) {
658        int j;
659
660        for (j = 0; j < filterSize; j++) {
661            if (j >= filter2Size)
662                filter[i * filterSize + j] = 0;
663            else
664                filter[i * filterSize + j] = filter2[i * filter2Size + j];
665            if ((flags & SWS_BITEXACT) && j >= minFilterSize)
666                filter[i * filterSize + j] = 0;
667        }
668    }
669
670    // FIXME try to align filterPos if possible
671
672    // fix borders
673    for (i = 0; i < dstW; i++) {
674        int j;
675        if ((*filterPos)[i] < 0) {
676            // move filter coefficients left to compensate for filterPos
677            for (j = 1; j < filterSize; j++) {
678                int left = FFMAX(j + (*filterPos)[i], 0);
679                filter[i * filterSize + left] += filter[i * filterSize + j];
680                filter[i * filterSize + j]     = 0;
681            }
682            (*filterPos)[i]= 0;
683        }
684
685        if ((*filterPos)[i] + filterSize > srcW) {
686            int shift = (*filterPos)[i] + FFMIN(filterSize - srcW, 0);
687            int64_t acc = 0;
688
689            for (j = filterSize - 1; j >= 0; j--) {
690                if ((*filterPos)[i] + j >= srcW) {
691                    acc += filter[i * filterSize + j];
692                    filter[i * filterSize + j] = 0;
693                }
694            }
695            for (j = filterSize - 1; j >= 0; j--) {
696                if (j < shift) {
697                    filter[i * filterSize + j] = 0;
698                } else {
699                    filter[i * filterSize + j] = filter[i * filterSize + j - shift];
700                }
701            }
702
703            (*filterPos)[i]-= shift;
704            filter[i * filterSize + srcW - 1 - (*filterPos)[i]] += acc;
705        }
706        av_assert0((*filterPos)[i] >= 0);
707        av_assert0((*filterPos)[i] < srcW);
708        if ((*filterPos)[i] + filterSize > srcW) {
709            for (j = 0; j < filterSize; j++) {
710                av_assert0((*filterPos)[i] + j < srcW || !filter[i * filterSize + j]);
711            }
712        }
713    }
714
715    // Note the +1 is for the MMX scaler which reads over the end
716    /* align at 16 for AltiVec (needed by hScale_altivec_real) */
717    if (!FF_ALLOCZ_TYPED_ARRAY(*outFilter, *outFilterSize * (dstW + 3)))
718        goto nomem;
719
720    /* normalize & store in outFilter */
721    for (i = 0; i < dstW; i++) {
722        int j;
723        int64_t error = 0;
724        int64_t sum   = 0;
725
726        for (j = 0; j < filterSize; j++) {
727            sum += filter[i * filterSize + j];
728        }
729        sum = (sum + one / 2) / one;
730        if (!sum) {
731            av_log(NULL, AV_LOG_WARNING, "SwScaler: zero vector in scaling\n");
732            sum = 1;
733        }
734        for (j = 0; j < *outFilterSize; j++) {
735            int64_t v = filter[i * filterSize + j] + error;
736            int intV  = ROUNDED_DIV(v, sum);
737            (*outFilter)[i * (*outFilterSize) + j] = intV;
738            error                                  = v - intV * sum;
739        }
740    }
741
742    (*filterPos)[dstW + 0] =
743    (*filterPos)[dstW + 1] =
744    (*filterPos)[dstW + 2] = (*filterPos)[dstW - 1]; /* the MMX/SSE scaler will
745                                                      * read over the end */
746    for (i = 0; i < *outFilterSize; i++) {
747        int k = (dstW - 1) * (*outFilterSize) + i;
748        (*outFilter)[k + 1 * (*outFilterSize)] =
749        (*outFilter)[k + 2 * (*outFilterSize)] =
750        (*outFilter)[k + 3 * (*outFilterSize)] = (*outFilter)[k];
751    }
752
753    ret = 0;
754    goto done;
755nomem:
756    ret = AVERROR(ENOMEM);
757fail:
758    if(ret < 0)
759        av_log(NULL, ret == RETCODE_USE_CASCADE ? AV_LOG_DEBUG : AV_LOG_ERROR, "sws: initFilter failed\n");
760done:
761    av_free(filter);
762    av_free(filter2);
763    return ret;
764}
765
766static void fill_rgb2yuv_table(SwsContext *c, const int table[4], int dstRange)
767{
768    int64_t W, V, Z, Cy, Cu, Cv;
769    int64_t vr =  table[0];
770    int64_t ub =  table[1];
771    int64_t ug = -table[2];
772    int64_t vg = -table[3];
773    int64_t ONE = 65536;
774    int64_t cy = ONE;
775    uint8_t *p = (uint8_t*)c->input_rgb2yuv_table;
776    int i;
777    static const int8_t map[] = {
778    BY_IDX, GY_IDX, -1    , BY_IDX, BY_IDX, GY_IDX, -1    , BY_IDX,
779    RY_IDX, -1    , GY_IDX, RY_IDX, RY_IDX, -1    , GY_IDX, RY_IDX,
780    RY_IDX, GY_IDX, -1    , RY_IDX, RY_IDX, GY_IDX, -1    , RY_IDX,
781    BY_IDX, -1    , GY_IDX, BY_IDX, BY_IDX, -1    , GY_IDX, BY_IDX,
782    BU_IDX, GU_IDX, -1    , BU_IDX, BU_IDX, GU_IDX, -1    , BU_IDX,
783    RU_IDX, -1    , GU_IDX, RU_IDX, RU_IDX, -1    , GU_IDX, RU_IDX,
784    RU_IDX, GU_IDX, -1    , RU_IDX, RU_IDX, GU_IDX, -1    , RU_IDX,
785    BU_IDX, -1    , GU_IDX, BU_IDX, BU_IDX, -1    , GU_IDX, BU_IDX,
786    BV_IDX, GV_IDX, -1    , BV_IDX, BV_IDX, GV_IDX, -1    , BV_IDX,
787    RV_IDX, -1    , GV_IDX, RV_IDX, RV_IDX, -1    , GV_IDX, RV_IDX,
788    RV_IDX, GV_IDX, -1    , RV_IDX, RV_IDX, GV_IDX, -1    , RV_IDX,
789    BV_IDX, -1    , GV_IDX, BV_IDX, BV_IDX, -1    , GV_IDX, BV_IDX,
790    RY_IDX, BY_IDX, RY_IDX, BY_IDX, RY_IDX, BY_IDX, RY_IDX, BY_IDX,
791    BY_IDX, RY_IDX, BY_IDX, RY_IDX, BY_IDX, RY_IDX, BY_IDX, RY_IDX,
792    GY_IDX, -1    , GY_IDX, -1    , GY_IDX, -1    , GY_IDX, -1    ,
793    -1    , GY_IDX, -1    , GY_IDX, -1    , GY_IDX, -1    , GY_IDX,
794    RU_IDX, BU_IDX, RU_IDX, BU_IDX, RU_IDX, BU_IDX, RU_IDX, BU_IDX,
795    BU_IDX, RU_IDX, BU_IDX, RU_IDX, BU_IDX, RU_IDX, BU_IDX, RU_IDX,
796    GU_IDX, -1    , GU_IDX, -1    , GU_IDX, -1    , GU_IDX, -1    ,
797    -1    , GU_IDX, -1    , GU_IDX, -1    , GU_IDX, -1    , GU_IDX,
798    RV_IDX, BV_IDX, RV_IDX, BV_IDX, RV_IDX, BV_IDX, RV_IDX, BV_IDX,
799    BV_IDX, RV_IDX, BV_IDX, RV_IDX, BV_IDX, RV_IDX, BV_IDX, RV_IDX,
800    GV_IDX, -1    , GV_IDX, -1    , GV_IDX, -1    , GV_IDX, -1    ,
801    -1    , GV_IDX, -1    , GV_IDX, -1    , GV_IDX, -1    , GV_IDX, //23
802    -1    , -1    , -1    , -1    , -1    , -1    , -1    , -1    , //24
803    -1    , -1    , -1    , -1    , -1    , -1    , -1    , -1    , //25
804    -1    , -1    , -1    , -1    , -1    , -1    , -1    , -1    , //26
805    -1    , -1    , -1    , -1    , -1    , -1    , -1    , -1    , //27
806    -1    , -1    , -1    , -1    , -1    , -1    , -1    , -1    , //28
807    -1    , -1    , -1    , -1    , -1    , -1    , -1    , -1    , //29
808    -1    , -1    , -1    , -1    , -1    , -1    , -1    , -1    , //30
809    -1    , -1    , -1    , -1    , -1    , -1    , -1    , -1    , //31
810    BY_IDX, GY_IDX, RY_IDX, -1    , -1    , -1    , -1    , -1    , //32
811    BU_IDX, GU_IDX, RU_IDX, -1    , -1    , -1    , -1    , -1    , //33
812    BV_IDX, GV_IDX, RV_IDX, -1    , -1    , -1    , -1    , -1    , //34
813    };
814
815    dstRange = 0; //FIXME range = 1 is handled elsewhere
816
817    if (!dstRange) {
818        cy = cy * 255 / 219;
819    } else {
820        vr = vr * 224 / 255;
821        ub = ub * 224 / 255;
822        ug = ug * 224 / 255;
823        vg = vg * 224 / 255;
824    }
825    W = ROUNDED_DIV(ONE*ONE*ug, ub);
826    V = ROUNDED_DIV(ONE*ONE*vg, vr);
827    Z = ONE*ONE-W-V;
828
829    Cy = ROUNDED_DIV(cy*Z, ONE);
830    Cu = ROUNDED_DIV(ub*Z, ONE);
831    Cv = ROUNDED_DIV(vr*Z, ONE);
832
833    c->input_rgb2yuv_table[RY_IDX] = -ROUNDED_DIV((1 << RGB2YUV_SHIFT)*V        , Cy);
834    c->input_rgb2yuv_table[GY_IDX] =  ROUNDED_DIV((1 << RGB2YUV_SHIFT)*ONE*ONE  , Cy);
835    c->input_rgb2yuv_table[BY_IDX] = -ROUNDED_DIV((1 << RGB2YUV_SHIFT)*W        , Cy);
836
837    c->input_rgb2yuv_table[RU_IDX] =  ROUNDED_DIV((1 << RGB2YUV_SHIFT)*V        , Cu);
838    c->input_rgb2yuv_table[GU_IDX] = -ROUNDED_DIV((1 << RGB2YUV_SHIFT)*ONE*ONE  , Cu);
839    c->input_rgb2yuv_table[BU_IDX] =  ROUNDED_DIV((1 << RGB2YUV_SHIFT)*(Z+W)    , Cu);
840
841    c->input_rgb2yuv_table[RV_IDX] =  ROUNDED_DIV((1 << RGB2YUV_SHIFT)*(V+Z)    , Cv);
842    c->input_rgb2yuv_table[GV_IDX] = -ROUNDED_DIV((1 << RGB2YUV_SHIFT)*ONE*ONE  , Cv);
843    c->input_rgb2yuv_table[BV_IDX] =  ROUNDED_DIV((1 << RGB2YUV_SHIFT)*W        , Cv);
844
845    if(/*!dstRange && */!memcmp(table, ff_yuv2rgb_coeffs[SWS_CS_DEFAULT], sizeof(ff_yuv2rgb_coeffs[SWS_CS_DEFAULT]))) {
846        c->input_rgb2yuv_table[BY_IDX] =  ((int)(0.114 * 219 / 255 * (1 << RGB2YUV_SHIFT) + 0.5));
847        c->input_rgb2yuv_table[BV_IDX] = (-(int)(0.081 * 224 / 255 * (1 << RGB2YUV_SHIFT) + 0.5));
848        c->input_rgb2yuv_table[BU_IDX] =  ((int)(0.500 * 224 / 255 * (1 << RGB2YUV_SHIFT) + 0.5));
849        c->input_rgb2yuv_table[GY_IDX] =  ((int)(0.587 * 219 / 255 * (1 << RGB2YUV_SHIFT) + 0.5));
850        c->input_rgb2yuv_table[GV_IDX] = (-(int)(0.419 * 224 / 255 * (1 << RGB2YUV_SHIFT) + 0.5));
851        c->input_rgb2yuv_table[GU_IDX] = (-(int)(0.331 * 224 / 255 * (1 << RGB2YUV_SHIFT) + 0.5));
852        c->input_rgb2yuv_table[RY_IDX] =  ((int)(0.299 * 219 / 255 * (1 << RGB2YUV_SHIFT) + 0.5));
853        c->input_rgb2yuv_table[RV_IDX] =  ((int)(0.500 * 224 / 255 * (1 << RGB2YUV_SHIFT) + 0.5));
854        c->input_rgb2yuv_table[RU_IDX] = (-(int)(0.169 * 224 / 255 * (1 << RGB2YUV_SHIFT) + 0.5));
855    }
856    for(i=0; i<FF_ARRAY_ELEMS(map); i++)
857        AV_WL16(p + 16*4 + 2*i, map[i] >= 0 ? c->input_rgb2yuv_table[map[i]] : 0);
858}
859
860static void fill_xyztables(struct SwsContext *c)
861{
862    int i;
863    double xyzgamma = XYZ_GAMMA;
864    double rgbgamma = 1.0 / RGB_GAMMA;
865    double xyzgammainv = 1.0 / XYZ_GAMMA;
866    double rgbgammainv = RGB_GAMMA;
867    static const int16_t xyz2rgb_matrix[3][4] = {
868        {13270, -6295, -2041},
869        {-3969,  7682,   170},
870        {  228,  -835,  4329} };
871    static const int16_t rgb2xyz_matrix[3][4] = {
872        {1689, 1464,  739},
873        { 871, 2929,  296},
874        {  79,  488, 3891} };
875    static int16_t xyzgamma_tab[4096], rgbgamma_tab[4096], xyzgammainv_tab[4096], rgbgammainv_tab[4096];
876
877    memcpy(c->xyz2rgb_matrix, xyz2rgb_matrix, sizeof(c->xyz2rgb_matrix));
878    memcpy(c->rgb2xyz_matrix, rgb2xyz_matrix, sizeof(c->rgb2xyz_matrix));
879    c->xyzgamma = xyzgamma_tab;
880    c->rgbgamma = rgbgamma_tab;
881    c->xyzgammainv = xyzgammainv_tab;
882    c->rgbgammainv = rgbgammainv_tab;
883
884    if (rgbgamma_tab[4095])
885        return;
886
887    /* set gamma vectors */
888    for (i = 0; i < 4096; i++) {
889        xyzgamma_tab[i] = lrint(pow(i / 4095.0, xyzgamma) * 4095.0);
890        rgbgamma_tab[i] = lrint(pow(i / 4095.0, rgbgamma) * 4095.0);
891        xyzgammainv_tab[i] = lrint(pow(i / 4095.0, xyzgammainv) * 4095.0);
892        rgbgammainv_tab[i] = lrint(pow(i / 4095.0, rgbgammainv) * 4095.0);
893    }
894}
895
896static int range_override_needed(enum AVPixelFormat format)
897{
898    return !isYUV(format) && !isGray(format);
899}
900
901int sws_setColorspaceDetails(struct SwsContext *c, const int inv_table[4],
902                             int srcRange, const int table[4], int dstRange,
903                             int brightness, int contrast, int saturation)
904{
905    const AVPixFmtDescriptor *desc_dst;
906    const AVPixFmtDescriptor *desc_src;
907    int need_reinit = 0;
908
909    if (c->nb_slice_ctx) {
910        int parent_ret = 0;
911        for (int i = 0; i < c->nb_slice_ctx; i++) {
912            int ret = sws_setColorspaceDetails(c->slice_ctx[i], inv_table,
913                                               srcRange, table, dstRange,
914                                               brightness, contrast, saturation);
915            if (ret < 0)
916                parent_ret = ret;
917        }
918
919        return parent_ret;
920    }
921
922    handle_formats(c);
923    desc_dst = av_pix_fmt_desc_get(c->dstFormat);
924    desc_src = av_pix_fmt_desc_get(c->srcFormat);
925
926    if(range_override_needed(c->dstFormat))
927        dstRange = 0;
928    if(range_override_needed(c->srcFormat))
929        srcRange = 0;
930
931    if (c->srcRange != srcRange ||
932        c->dstRange != dstRange ||
933        c->brightness != brightness ||
934        c->contrast   != contrast ||
935        c->saturation != saturation ||
936        memcmp(c->srcColorspaceTable, inv_table, sizeof(int) * 4) ||
937        memcmp(c->dstColorspaceTable,     table, sizeof(int) * 4)
938    )
939        need_reinit = 1;
940
941    memmove(c->srcColorspaceTable, inv_table, sizeof(int) * 4);
942    memmove(c->dstColorspaceTable, table, sizeof(int) * 4);
943
944
945
946    c->brightness = brightness;
947    c->contrast   = contrast;
948    c->saturation = saturation;
949    c->srcRange   = srcRange;
950    c->dstRange   = dstRange;
951
952    //The srcBpc check is possibly wrong but we seem to lack a definitive reference to test this
953    //and what we have in ticket 2939 looks better with this check
954    if (need_reinit && (c->srcBpc == 8 || !isYUV(c->srcFormat)))
955        ff_sws_init_range_convert(c);
956
957    c->dstFormatBpp = av_get_bits_per_pixel(desc_dst);
958    c->srcFormatBpp = av_get_bits_per_pixel(desc_src);
959
960    if (c->cascaded_context[c->cascaded_mainindex])
961        return sws_setColorspaceDetails(c->cascaded_context[c->cascaded_mainindex],inv_table, srcRange,table, dstRange, brightness,  contrast, saturation);
962
963    if (!need_reinit)
964        return 0;
965
966    if ((isYUV(c->dstFormat) || isGray(c->dstFormat)) && (isYUV(c->srcFormat) || isGray(c->srcFormat))) {
967        if (!c->cascaded_context[0] &&
968            memcmp(c->dstColorspaceTable, c->srcColorspaceTable, sizeof(int) * 4) &&
969            c->srcW && c->srcH && c->dstW && c->dstH) {
970            enum AVPixelFormat tmp_format;
971            int tmp_width, tmp_height;
972            int srcW = c->srcW;
973            int srcH = c->srcH;
974            int dstW = c->dstW;
975            int dstH = c->dstH;
976            int ret;
977            av_log(c, AV_LOG_VERBOSE, "YUV color matrix differs for YUV->YUV, using intermediate RGB to convert\n");
978
979            if (isNBPS(c->dstFormat) || is16BPS(c->dstFormat)) {
980                if (isALPHA(c->srcFormat) && isALPHA(c->dstFormat)) {
981                    tmp_format = AV_PIX_FMT_BGRA64;
982                } else {
983                    tmp_format = AV_PIX_FMT_BGR48;
984                }
985            } else {
986                if (isALPHA(c->srcFormat) && isALPHA(c->dstFormat)) {
987                    tmp_format = AV_PIX_FMT_BGRA;
988                } else {
989                    tmp_format = AV_PIX_FMT_BGR24;
990                }
991            }
992
993            if (srcW*srcH > dstW*dstH) {
994                tmp_width  = dstW;
995                tmp_height = dstH;
996            } else {
997                tmp_width  = srcW;
998                tmp_height = srcH;
999            }
1000
1001            ret = av_image_alloc(c->cascaded_tmp, c->cascaded_tmpStride,
1002                                tmp_width, tmp_height, tmp_format, 64);
1003            if (ret < 0)
1004                return ret;
1005
1006            c->cascaded_context[0] = sws_alloc_set_opts(srcW, srcH, c->srcFormat,
1007                                                        tmp_width, tmp_height, tmp_format,
1008                                                        c->flags, c->param);
1009            if (!c->cascaded_context[0])
1010                return -1;
1011
1012            c->cascaded_context[0]->alphablend = c->alphablend;
1013            ret = sws_init_context(c->cascaded_context[0], NULL , NULL);
1014            if (ret < 0)
1015                return ret;
1016            //we set both src and dst depending on that the RGB side will be ignored
1017            sws_setColorspaceDetails(c->cascaded_context[0], inv_table,
1018                                     srcRange, table, dstRange,
1019                                     brightness, contrast, saturation);
1020
1021            c->cascaded_context[1] = sws_alloc_set_opts(tmp_width, tmp_height, tmp_format,
1022                                                        dstW, dstH, c->dstFormat,
1023                                                        c->flags, c->param);
1024            if (!c->cascaded_context[1])
1025                return -1;
1026            c->cascaded_context[1]->srcRange = srcRange;
1027            c->cascaded_context[1]->dstRange = dstRange;
1028            ret = sws_init_context(c->cascaded_context[1], NULL , NULL);
1029            if (ret < 0)
1030                return ret;
1031            sws_setColorspaceDetails(c->cascaded_context[1], inv_table,
1032                                     srcRange, table, dstRange,
1033                                     0, 1 << 16, 1 << 16);
1034            return 0;
1035        }
1036        //We do not support this combination currently, we need to cascade more contexts to compensate
1037        if (c->cascaded_context[0] && memcmp(c->dstColorspaceTable, c->srcColorspaceTable, sizeof(int) * 4))
1038            return -1; //AVERROR_PATCHWELCOME;
1039        return 0;
1040    }
1041
1042    if (!isYUV(c->dstFormat) && !isGray(c->dstFormat)) {
1043        ff_yuv2rgb_c_init_tables(c, inv_table, srcRange, brightness,
1044                                 contrast, saturation);
1045        // FIXME factorize
1046
1047#if ARCH_PPC
1048        ff_yuv2rgb_init_tables_ppc(c, inv_table, brightness,
1049                                   contrast, saturation);
1050#endif
1051    }
1052
1053    fill_rgb2yuv_table(c, table, dstRange);
1054
1055    return 0;
1056}
1057
1058int sws_getColorspaceDetails(struct SwsContext *c, int **inv_table,
1059                             int *srcRange, int **table, int *dstRange,
1060                             int *brightness, int *contrast, int *saturation)
1061{
1062    if (!c )
1063        return -1;
1064
1065    if (c->nb_slice_ctx) {
1066        return sws_getColorspaceDetails(c->slice_ctx[0], inv_table, srcRange,
1067                                        table, dstRange, brightness, contrast,
1068                                        saturation);
1069    }
1070
1071    *inv_table  = c->srcColorspaceTable;
1072    *table      = c->dstColorspaceTable;
1073    *srcRange   = range_override_needed(c->srcFormat) ? 1 : c->srcRange;
1074    *dstRange   = range_override_needed(c->dstFormat) ? 1 : c->dstRange;
1075    *brightness = c->brightness;
1076    *contrast   = c->contrast;
1077    *saturation = c->saturation;
1078
1079    return 0;
1080}
1081
1082static int handle_jpeg(enum AVPixelFormat *format)
1083{
1084    switch (*format) {
1085    case AV_PIX_FMT_YUVJ420P:
1086        *format = AV_PIX_FMT_YUV420P;
1087        return 1;
1088    case AV_PIX_FMT_YUVJ411P:
1089        *format = AV_PIX_FMT_YUV411P;
1090        return 1;
1091    case AV_PIX_FMT_YUVJ422P:
1092        *format = AV_PIX_FMT_YUV422P;
1093        return 1;
1094    case AV_PIX_FMT_YUVJ444P:
1095        *format = AV_PIX_FMT_YUV444P;
1096        return 1;
1097    case AV_PIX_FMT_YUVJ440P:
1098        *format = AV_PIX_FMT_YUV440P;
1099        return 1;
1100    case AV_PIX_FMT_GRAY8:
1101    case AV_PIX_FMT_YA8:
1102    case AV_PIX_FMT_GRAY9LE:
1103    case AV_PIX_FMT_GRAY9BE:
1104    case AV_PIX_FMT_GRAY10LE:
1105    case AV_PIX_FMT_GRAY10BE:
1106    case AV_PIX_FMT_GRAY12LE:
1107    case AV_PIX_FMT_GRAY12BE:
1108    case AV_PIX_FMT_GRAY14LE:
1109    case AV_PIX_FMT_GRAY14BE:
1110    case AV_PIX_FMT_GRAY16LE:
1111    case AV_PIX_FMT_GRAY16BE:
1112    case AV_PIX_FMT_YA16BE:
1113    case AV_PIX_FMT_YA16LE:
1114        return 1;
1115    default:
1116        return 0;
1117    }
1118}
1119
1120static int handle_0alpha(enum AVPixelFormat *format)
1121{
1122    switch (*format) {
1123    case AV_PIX_FMT_0BGR    : *format = AV_PIX_FMT_ABGR   ; return 1;
1124    case AV_PIX_FMT_BGR0    : *format = AV_PIX_FMT_BGRA   ; return 4;
1125    case AV_PIX_FMT_0RGB    : *format = AV_PIX_FMT_ARGB   ; return 1;
1126    case AV_PIX_FMT_RGB0    : *format = AV_PIX_FMT_RGBA   ; return 4;
1127    default:                                          return 0;
1128    }
1129}
1130
1131static int handle_xyz(enum AVPixelFormat *format)
1132{
1133    switch (*format) {
1134    case AV_PIX_FMT_XYZ12BE : *format = AV_PIX_FMT_RGB48BE; return 1;
1135    case AV_PIX_FMT_XYZ12LE : *format = AV_PIX_FMT_RGB48LE; return 1;
1136    default:                                                return 0;
1137    }
1138}
1139
1140static void handle_formats(SwsContext *c)
1141{
1142    c->src0Alpha |= handle_0alpha(&c->srcFormat);
1143    c->dst0Alpha |= handle_0alpha(&c->dstFormat);
1144    c->srcXYZ    |= handle_xyz(&c->srcFormat);
1145    c->dstXYZ    |= handle_xyz(&c->dstFormat);
1146    if (c->srcXYZ || c->dstXYZ)
1147        fill_xyztables(c);
1148}
1149
1150SwsContext *sws_alloc_context(void)
1151{
1152    SwsContext *c = av_mallocz(sizeof(SwsContext));
1153
1154    av_assert0(offsetof(SwsContext, redDither) + DITHER32_INT == offsetof(SwsContext, dither32));
1155
1156    if (c) {
1157        c->av_class = &ff_sws_context_class;
1158        av_opt_set_defaults(c);
1159        atomic_init(&c->stride_unaligned_warned, 0);
1160        atomic_init(&c->data_unaligned_warned,   0);
1161    }
1162
1163    return c;
1164}
1165
1166static uint16_t * alloc_gamma_tbl(double e)
1167{
1168    int i = 0;
1169    uint16_t * tbl;
1170    tbl = (uint16_t*)av_malloc(sizeof(uint16_t) * 1 << 16);
1171    if (!tbl)
1172        return NULL;
1173
1174    for (i = 0; i < 65536; ++i) {
1175        tbl[i] = pow(i / 65535.0, e) * 65535.0;
1176    }
1177    return tbl;
1178}
1179
1180static enum AVPixelFormat alphaless_fmt(enum AVPixelFormat fmt)
1181{
1182    switch(fmt) {
1183    case AV_PIX_FMT_ARGB:       return AV_PIX_FMT_RGB24;
1184    case AV_PIX_FMT_RGBA:       return AV_PIX_FMT_RGB24;
1185    case AV_PIX_FMT_ABGR:       return AV_PIX_FMT_BGR24;
1186    case AV_PIX_FMT_BGRA:       return AV_PIX_FMT_BGR24;
1187    case AV_PIX_FMT_YA8:        return AV_PIX_FMT_GRAY8;
1188
1189    case AV_PIX_FMT_YUVA420P:   return AV_PIX_FMT_YUV420P;
1190    case AV_PIX_FMT_YUVA422P:   return AV_PIX_FMT_YUV422P;
1191    case AV_PIX_FMT_YUVA444P:           return AV_PIX_FMT_YUV444P;
1192
1193    case AV_PIX_FMT_GBRAP:              return AV_PIX_FMT_GBRP;
1194
1195    case AV_PIX_FMT_GBRAP10LE:          return AV_PIX_FMT_GBRP10;
1196    case AV_PIX_FMT_GBRAP10BE:          return AV_PIX_FMT_GBRP10;
1197
1198    case AV_PIX_FMT_GBRAP12LE:          return AV_PIX_FMT_GBRP12;
1199    case AV_PIX_FMT_GBRAP12BE:          return AV_PIX_FMT_GBRP12;
1200
1201    case AV_PIX_FMT_GBRAP16LE:          return AV_PIX_FMT_GBRP16;
1202    case AV_PIX_FMT_GBRAP16BE:          return AV_PIX_FMT_GBRP16;
1203
1204    case AV_PIX_FMT_RGBA64LE:   return AV_PIX_FMT_RGB48;
1205    case AV_PIX_FMT_RGBA64BE:   return AV_PIX_FMT_RGB48;
1206    case AV_PIX_FMT_BGRA64LE:   return AV_PIX_FMT_BGR48;
1207    case AV_PIX_FMT_BGRA64BE:   return AV_PIX_FMT_BGR48;
1208
1209    case AV_PIX_FMT_YA16BE:             return AV_PIX_FMT_GRAY16;
1210    case AV_PIX_FMT_YA16LE:             return AV_PIX_FMT_GRAY16;
1211
1212    case AV_PIX_FMT_YUVA420P9BE:        return AV_PIX_FMT_YUV420P9;
1213    case AV_PIX_FMT_YUVA422P9BE:        return AV_PIX_FMT_YUV422P9;
1214    case AV_PIX_FMT_YUVA444P9BE:        return AV_PIX_FMT_YUV444P9;
1215    case AV_PIX_FMT_YUVA420P9LE:        return AV_PIX_FMT_YUV420P9;
1216    case AV_PIX_FMT_YUVA422P9LE:        return AV_PIX_FMT_YUV422P9;
1217    case AV_PIX_FMT_YUVA444P9LE:        return AV_PIX_FMT_YUV444P9;
1218    case AV_PIX_FMT_YUVA420P10BE:       return AV_PIX_FMT_YUV420P10;
1219    case AV_PIX_FMT_YUVA422P10BE:       return AV_PIX_FMT_YUV422P10;
1220    case AV_PIX_FMT_YUVA444P10BE:       return AV_PIX_FMT_YUV444P10;
1221    case AV_PIX_FMT_YUVA420P10LE:       return AV_PIX_FMT_YUV420P10;
1222    case AV_PIX_FMT_YUVA422P10LE:       return AV_PIX_FMT_YUV422P10;
1223    case AV_PIX_FMT_YUVA444P10LE:       return AV_PIX_FMT_YUV444P10;
1224    case AV_PIX_FMT_YUVA420P16BE:       return AV_PIX_FMT_YUV420P16;
1225    case AV_PIX_FMT_YUVA422P16BE:       return AV_PIX_FMT_YUV422P16;
1226    case AV_PIX_FMT_YUVA444P16BE:       return AV_PIX_FMT_YUV444P16;
1227    case AV_PIX_FMT_YUVA420P16LE:       return AV_PIX_FMT_YUV420P16;
1228    case AV_PIX_FMT_YUVA422P16LE:       return AV_PIX_FMT_YUV422P16;
1229    case AV_PIX_FMT_YUVA444P16LE:       return AV_PIX_FMT_YUV444P16;
1230
1231//     case AV_PIX_FMT_AYUV64LE:
1232//     case AV_PIX_FMT_AYUV64BE:
1233//     case AV_PIX_FMT_PAL8:
1234    default: return AV_PIX_FMT_NONE;
1235    }
1236}
1237
1238static int context_init_threaded(SwsContext *c,
1239                                 SwsFilter *src_filter, SwsFilter *dst_filter)
1240{
1241    int ret;
1242
1243    ret = avpriv_slicethread_create(&c->slicethread, (void*)c,
1244                                    ff_sws_slice_worker, NULL, c->nb_threads);
1245    if (ret == AVERROR(ENOSYS)) {
1246        c->nb_threads = 1;
1247        return 0;
1248    } else if (ret < 0)
1249        return ret;
1250
1251    c->nb_threads = ret;
1252
1253    c->slice_ctx = av_calloc(c->nb_threads, sizeof(*c->slice_ctx));
1254    c->slice_err = av_calloc(c->nb_threads, sizeof(*c->slice_err));
1255    if (!c->slice_ctx || !c->slice_err)
1256        return AVERROR(ENOMEM);
1257
1258    for (int i = 0; i < c->nb_threads; i++) {
1259        c->slice_ctx[i] = sws_alloc_context();
1260        if (!c->slice_ctx[i])
1261            return AVERROR(ENOMEM);
1262
1263        c->slice_ctx[i]->parent = c;
1264
1265        ret = av_opt_copy((void*)c->slice_ctx[i], (void*)c);
1266        if (ret < 0)
1267            return ret;
1268
1269        c->slice_ctx[i]->nb_threads = 1;
1270
1271        ret = sws_init_context(c->slice_ctx[i], src_filter, dst_filter);
1272        if (ret < 0)
1273            return ret;
1274
1275        c->nb_slice_ctx++;
1276
1277        if (c->slice_ctx[i]->dither == SWS_DITHER_ED) {
1278            av_log(c, AV_LOG_VERBOSE,
1279                   "Error-diffusion dither is in use, scaling will be single-threaded.");
1280            break;
1281        }
1282    }
1283
1284    c->frame_src = av_frame_alloc();
1285    c->frame_dst = av_frame_alloc();
1286    if (!c->frame_src || !c->frame_dst)
1287        return AVERROR(ENOMEM);
1288
1289    return 0;
1290}
1291
1292av_cold int sws_init_context(SwsContext *c, SwsFilter *srcFilter,
1293                             SwsFilter *dstFilter)
1294{
1295    int i;
1296    int usesVFilter, usesHFilter;
1297    int unscaled;
1298    SwsFilter dummyFilter = { NULL, NULL, NULL, NULL };
1299    int srcW              = c->srcW;
1300    int srcH              = c->srcH;
1301    int dstW              = c->dstW;
1302    int dstH              = c->dstH;
1303    int dst_stride        = FFALIGN(dstW * sizeof(int16_t) + 66, 16);
1304    int flags, cpu_flags;
1305    enum AVPixelFormat srcFormat = c->srcFormat;
1306    enum AVPixelFormat dstFormat = c->dstFormat;
1307    const AVPixFmtDescriptor *desc_src;
1308    const AVPixFmtDescriptor *desc_dst;
1309    int ret = 0;
1310    enum AVPixelFormat tmpFmt;
1311    static const float float_mult = 1.0f / 255.0f;
1312    static AVOnce rgb2rgb_once = AV_ONCE_INIT;
1313
1314    if (c->nb_threads != 1) {
1315        ret = context_init_threaded(c, srcFilter, dstFilter);
1316        if (ret < 0 || c->nb_threads > 1)
1317            return ret;
1318        // threading disabled in this build, init as single-threaded
1319    }
1320
1321    cpu_flags = av_get_cpu_flags();
1322    flags     = c->flags;
1323    emms_c();
1324    if (ff_thread_once(&rgb2rgb_once, ff_sws_rgb2rgb_init) != 0)
1325        return AVERROR_UNKNOWN;
1326
1327    unscaled = (srcW == dstW && srcH == dstH);
1328
1329    c->srcRange |= handle_jpeg(&c->srcFormat);
1330    c->dstRange |= handle_jpeg(&c->dstFormat);
1331
1332    if(srcFormat!=c->srcFormat || dstFormat!=c->dstFormat)
1333        av_log(c, AV_LOG_WARNING, "deprecated pixel format used, make sure you did set range correctly\n");
1334
1335    if (!c->contrast && !c->saturation && !c->dstFormatBpp)
1336        sws_setColorspaceDetails(c, ff_yuv2rgb_coeffs[SWS_CS_DEFAULT], c->srcRange,
1337                                 ff_yuv2rgb_coeffs[SWS_CS_DEFAULT],
1338                                 c->dstRange, 0, 1 << 16, 1 << 16);
1339
1340    handle_formats(c);
1341    srcFormat = c->srcFormat;
1342    dstFormat = c->dstFormat;
1343    desc_src = av_pix_fmt_desc_get(srcFormat);
1344    desc_dst = av_pix_fmt_desc_get(dstFormat);
1345
1346    // If the source has no alpha then disable alpha blendaway
1347    if (c->src0Alpha)
1348        c->alphablend = SWS_ALPHA_BLEND_NONE;
1349
1350    if (!(unscaled && sws_isSupportedEndiannessConversion(srcFormat) &&
1351          av_pix_fmt_swap_endianness(srcFormat) == dstFormat)) {
1352    if (!sws_isSupportedInput(srcFormat)) {
1353        av_log(c, AV_LOG_ERROR, "%s is not supported as input pixel format\n",
1354               av_get_pix_fmt_name(srcFormat));
1355        return AVERROR(EINVAL);
1356    }
1357    if (!sws_isSupportedOutput(dstFormat)) {
1358        av_log(c, AV_LOG_ERROR, "%s is not supported as output pixel format\n",
1359               av_get_pix_fmt_name(dstFormat));
1360        return AVERROR(EINVAL);
1361    }
1362    }
1363    av_assert2(desc_src && desc_dst);
1364
1365    i = flags & (SWS_POINT         |
1366                 SWS_AREA          |
1367                 SWS_BILINEAR      |
1368                 SWS_FAST_BILINEAR |
1369                 SWS_BICUBIC       |
1370                 SWS_X             |
1371                 SWS_GAUSS         |
1372                 SWS_LANCZOS       |
1373                 SWS_SINC          |
1374                 SWS_SPLINE        |
1375                 SWS_BICUBLIN);
1376
1377    /* provide a default scaler if not set by caller */
1378    if (!i) {
1379        if (dstW < srcW && dstH < srcH)
1380            flags |= SWS_BICUBIC;
1381        else if (dstW > srcW && dstH > srcH)
1382            flags |= SWS_BICUBIC;
1383        else
1384            flags |= SWS_BICUBIC;
1385        c->flags = flags;
1386    } else if (i & (i - 1)) {
1387        av_log(c, AV_LOG_ERROR,
1388               "Exactly one scaler algorithm must be chosen, got %X\n", i);
1389        return AVERROR(EINVAL);
1390    }
1391    /* sanity check */
1392    if (srcW < 1 || srcH < 1 || dstW < 1 || dstH < 1) {
1393        /* FIXME check if these are enough and try to lower them after
1394         * fixing the relevant parts of the code */
1395        av_log(c, AV_LOG_ERROR, "%dx%d -> %dx%d is invalid scaling dimension\n",
1396               srcW, srcH, dstW, dstH);
1397        return AVERROR(EINVAL);
1398    }
1399    if (flags & SWS_FAST_BILINEAR) {
1400        if (srcW < 8 || dstW < 8) {
1401            flags ^= SWS_FAST_BILINEAR | SWS_BILINEAR;
1402            c->flags = flags;
1403        }
1404    }
1405
1406    if (!dstFilter)
1407        dstFilter = &dummyFilter;
1408    if (!srcFilter)
1409        srcFilter = &dummyFilter;
1410
1411    c->lumXInc      = (((int64_t)srcW << 16) + (dstW >> 1)) / dstW;
1412    c->lumYInc      = (((int64_t)srcH << 16) + (dstH >> 1)) / dstH;
1413    c->dstFormatBpp = av_get_bits_per_pixel(desc_dst);
1414    c->srcFormatBpp = av_get_bits_per_pixel(desc_src);
1415    c->vRounder     = 4 * 0x0001000100010001ULL;
1416
1417    usesVFilter = (srcFilter->lumV && srcFilter->lumV->length > 1) ||
1418                  (srcFilter->chrV && srcFilter->chrV->length > 1) ||
1419                  (dstFilter->lumV && dstFilter->lumV->length > 1) ||
1420                  (dstFilter->chrV && dstFilter->chrV->length > 1);
1421    usesHFilter = (srcFilter->lumH && srcFilter->lumH->length > 1) ||
1422                  (srcFilter->chrH && srcFilter->chrH->length > 1) ||
1423                  (dstFilter->lumH && dstFilter->lumH->length > 1) ||
1424                  (dstFilter->chrH && dstFilter->chrH->length > 1);
1425
1426    av_pix_fmt_get_chroma_sub_sample(srcFormat, &c->chrSrcHSubSample, &c->chrSrcVSubSample);
1427    av_pix_fmt_get_chroma_sub_sample(dstFormat, &c->chrDstHSubSample, &c->chrDstVSubSample);
1428
1429    c->dst_slice_align = 1 << c->chrDstVSubSample;
1430
1431    if (isAnyRGB(dstFormat) && !(flags&SWS_FULL_CHR_H_INT)) {
1432        if (dstW&1) {
1433            av_log(c, AV_LOG_DEBUG, "Forcing full internal H chroma due to odd output size\n");
1434            flags |= SWS_FULL_CHR_H_INT;
1435            c->flags = flags;
1436        }
1437
1438        if (   c->chrSrcHSubSample == 0
1439            && c->chrSrcVSubSample == 0
1440            && c->dither != SWS_DITHER_BAYER //SWS_FULL_CHR_H_INT is currently not supported with SWS_DITHER_BAYER
1441            && !(c->flags & SWS_FAST_BILINEAR)
1442        ) {
1443            av_log(c, AV_LOG_DEBUG, "Forcing full internal H chroma due to input having non subsampled chroma\n");
1444            flags |= SWS_FULL_CHR_H_INT;
1445            c->flags = flags;
1446        }
1447    }
1448
1449    if (c->dither == SWS_DITHER_AUTO) {
1450        if (flags & SWS_ERROR_DIFFUSION)
1451            c->dither = SWS_DITHER_ED;
1452    }
1453
1454    if(dstFormat == AV_PIX_FMT_BGR4_BYTE ||
1455       dstFormat == AV_PIX_FMT_RGB4_BYTE ||
1456       dstFormat == AV_PIX_FMT_BGR8 ||
1457       dstFormat == AV_PIX_FMT_RGB8) {
1458        if (c->dither == SWS_DITHER_AUTO)
1459            c->dither = (flags & SWS_FULL_CHR_H_INT) ? SWS_DITHER_ED : SWS_DITHER_BAYER;
1460        if (!(flags & SWS_FULL_CHR_H_INT)) {
1461            if (c->dither == SWS_DITHER_ED || c->dither == SWS_DITHER_A_DITHER || c->dither == SWS_DITHER_X_DITHER || c->dither == SWS_DITHER_NONE) {
1462                av_log(c, AV_LOG_DEBUG,
1463                    "Desired dithering only supported in full chroma interpolation for destination format '%s'\n",
1464                    av_get_pix_fmt_name(dstFormat));
1465                flags   |= SWS_FULL_CHR_H_INT;
1466                c->flags = flags;
1467            }
1468        }
1469        if (flags & SWS_FULL_CHR_H_INT) {
1470            if (c->dither == SWS_DITHER_BAYER) {
1471                av_log(c, AV_LOG_DEBUG,
1472                    "Ordered dither is not supported in full chroma interpolation for destination format '%s'\n",
1473                    av_get_pix_fmt_name(dstFormat));
1474                c->dither = SWS_DITHER_ED;
1475            }
1476        }
1477    }
1478    if (isPlanarRGB(dstFormat)) {
1479        if (!(flags & SWS_FULL_CHR_H_INT)) {
1480            av_log(c, AV_LOG_DEBUG,
1481                   "%s output is not supported with half chroma resolution, switching to full\n",
1482                   av_get_pix_fmt_name(dstFormat));
1483            flags   |= SWS_FULL_CHR_H_INT;
1484            c->flags = flags;
1485        }
1486    }
1487
1488    /* reuse chroma for 2 pixels RGB/BGR unless user wants full
1489     * chroma interpolation */
1490    if (flags & SWS_FULL_CHR_H_INT &&
1491        isAnyRGB(dstFormat)        &&
1492        !isPlanarRGB(dstFormat)    &&
1493        dstFormat != AV_PIX_FMT_RGBA64LE &&
1494        dstFormat != AV_PIX_FMT_RGBA64BE &&
1495        dstFormat != AV_PIX_FMT_BGRA64LE &&
1496        dstFormat != AV_PIX_FMT_BGRA64BE &&
1497        dstFormat != AV_PIX_FMT_RGB48LE &&
1498        dstFormat != AV_PIX_FMT_RGB48BE &&
1499        dstFormat != AV_PIX_FMT_BGR48LE &&
1500        dstFormat != AV_PIX_FMT_BGR48BE &&
1501        dstFormat != AV_PIX_FMT_RGBA  &&
1502        dstFormat != AV_PIX_FMT_ARGB  &&
1503        dstFormat != AV_PIX_FMT_BGRA  &&
1504        dstFormat != AV_PIX_FMT_ABGR  &&
1505        dstFormat != AV_PIX_FMT_RGB24 &&
1506        dstFormat != AV_PIX_FMT_BGR24 &&
1507        dstFormat != AV_PIX_FMT_BGR4_BYTE &&
1508        dstFormat != AV_PIX_FMT_RGB4_BYTE &&
1509        dstFormat != AV_PIX_FMT_BGR8 &&
1510        dstFormat != AV_PIX_FMT_RGB8
1511    ) {
1512        av_log(c, AV_LOG_WARNING,
1513               "full chroma interpolation for destination format '%s' not yet implemented\n",
1514               av_get_pix_fmt_name(dstFormat));
1515        flags   &= ~SWS_FULL_CHR_H_INT;
1516        c->flags = flags;
1517    }
1518    if (isAnyRGB(dstFormat) && !(flags & SWS_FULL_CHR_H_INT))
1519        c->chrDstHSubSample = 1;
1520
1521    // drop some chroma lines if the user wants it
1522    c->vChrDrop          = (flags & SWS_SRC_V_CHR_DROP_MASK) >>
1523                           SWS_SRC_V_CHR_DROP_SHIFT;
1524    c->chrSrcVSubSample += c->vChrDrop;
1525
1526    /* drop every other pixel for chroma calculation unless user
1527     * wants full chroma */
1528    if (isAnyRGB(srcFormat) && !(flags & SWS_FULL_CHR_H_INP)   &&
1529        srcFormat != AV_PIX_FMT_RGB8 && srcFormat != AV_PIX_FMT_BGR8 &&
1530        srcFormat != AV_PIX_FMT_RGB4 && srcFormat != AV_PIX_FMT_BGR4 &&
1531        srcFormat != AV_PIX_FMT_RGB4_BYTE && srcFormat != AV_PIX_FMT_BGR4_BYTE &&
1532        srcFormat != AV_PIX_FMT_GBRP9BE   && srcFormat != AV_PIX_FMT_GBRP9LE  &&
1533        srcFormat != AV_PIX_FMT_GBRP10BE  && srcFormat != AV_PIX_FMT_GBRP10LE &&
1534        srcFormat != AV_PIX_FMT_GBRAP10BE && srcFormat != AV_PIX_FMT_GBRAP10LE &&
1535        srcFormat != AV_PIX_FMT_GBRP12BE  && srcFormat != AV_PIX_FMT_GBRP12LE &&
1536        srcFormat != AV_PIX_FMT_GBRAP12BE && srcFormat != AV_PIX_FMT_GBRAP12LE &&
1537        srcFormat != AV_PIX_FMT_GBRP14BE  && srcFormat != AV_PIX_FMT_GBRP14LE &&
1538        srcFormat != AV_PIX_FMT_GBRP16BE  && srcFormat != AV_PIX_FMT_GBRP16LE &&
1539        srcFormat != AV_PIX_FMT_GBRAP16BE  && srcFormat != AV_PIX_FMT_GBRAP16LE &&
1540        srcFormat != AV_PIX_FMT_GBRPF32BE  && srcFormat != AV_PIX_FMT_GBRPF32LE &&
1541        srcFormat != AV_PIX_FMT_GBRAPF32BE && srcFormat != AV_PIX_FMT_GBRAPF32LE &&
1542        ((dstW >> c->chrDstHSubSample) <= (srcW >> 1) ||
1543         (flags & SWS_FAST_BILINEAR)))
1544        c->chrSrcHSubSample = 1;
1545
1546    // Note the AV_CEIL_RSHIFT is so that we always round toward +inf.
1547    c->chrSrcW = AV_CEIL_RSHIFT(srcW, c->chrSrcHSubSample);
1548    c->chrSrcH = AV_CEIL_RSHIFT(srcH, c->chrSrcVSubSample);
1549    c->chrDstW = AV_CEIL_RSHIFT(dstW, c->chrDstHSubSample);
1550    c->chrDstH = AV_CEIL_RSHIFT(dstH, c->chrDstVSubSample);
1551
1552    if (!FF_ALLOCZ_TYPED_ARRAY(c->formatConvBuffer, FFALIGN(srcW * 2 + 78, 16) * 2))
1553        goto nomem;
1554
1555    c->frame_src = av_frame_alloc();
1556    c->frame_dst = av_frame_alloc();
1557    if (!c->frame_src || !c->frame_dst)
1558        goto nomem;
1559
1560    c->srcBpc = desc_src->comp[0].depth;
1561    if (c->srcBpc < 8)
1562        c->srcBpc = 8;
1563    c->dstBpc = desc_dst->comp[0].depth;
1564    if (c->dstBpc < 8)
1565        c->dstBpc = 8;
1566    if (isAnyRGB(srcFormat) || srcFormat == AV_PIX_FMT_PAL8)
1567        c->srcBpc = 16;
1568    if (c->dstBpc == 16)
1569        dst_stride <<= 1;
1570
1571    if (INLINE_MMXEXT(cpu_flags) && c->srcBpc == 8 && c->dstBpc <= 14) {
1572        c->canMMXEXTBeUsed = dstW >= srcW && (dstW & 31) == 0 &&
1573                             c->chrDstW >= c->chrSrcW &&
1574                             (srcW & 15) == 0;
1575        if (!c->canMMXEXTBeUsed && dstW >= srcW && c->chrDstW >= c->chrSrcW && (srcW & 15) == 0
1576
1577            && (flags & SWS_FAST_BILINEAR)) {
1578            if (flags & SWS_PRINT_INFO)
1579                av_log(c, AV_LOG_INFO,
1580                       "output width is not a multiple of 32 -> no MMXEXT scaler\n");
1581        }
1582        if (usesHFilter || isNBPS(c->srcFormat) || is16BPS(c->srcFormat) || isAnyRGB(c->srcFormat))
1583            c->canMMXEXTBeUsed = 0;
1584    } else
1585        c->canMMXEXTBeUsed = 0;
1586
1587    c->chrXInc = (((int64_t)c->chrSrcW << 16) + (c->chrDstW >> 1)) / c->chrDstW;
1588    c->chrYInc = (((int64_t)c->chrSrcH << 16) + (c->chrDstH >> 1)) / c->chrDstH;
1589
1590    /* Match pixel 0 of the src to pixel 0 of dst and match pixel n-2 of src
1591     * to pixel n-2 of dst, but only for the FAST_BILINEAR mode otherwise do
1592     * correct scaling.
1593     * n-2 is the last chrominance sample available.
1594     * This is not perfect, but no one should notice the difference, the more
1595     * correct variant would be like the vertical one, but that would require
1596     * some special code for the first and last pixel */
1597    if (flags & SWS_FAST_BILINEAR) {
1598        if (c->canMMXEXTBeUsed) {
1599            c->lumXInc += 20;
1600            c->chrXInc += 20;
1601        }
1602        // we don't use the x86 asm scaler if MMX is available
1603        else if (INLINE_MMX(cpu_flags) && c->dstBpc <= 14) {
1604            c->lumXInc = ((int64_t)(srcW       - 2) << 16) / (dstW       - 2) - 20;
1605            c->chrXInc = ((int64_t)(c->chrSrcW - 2) << 16) / (c->chrDstW - 2) - 20;
1606        }
1607    }
1608
1609    // hardcoded for now
1610    c->gamma_value = 2.2;
1611    tmpFmt = AV_PIX_FMT_RGBA64LE;
1612
1613
1614    if (!unscaled && c->gamma_flag && (srcFormat != tmpFmt || dstFormat != tmpFmt)) {
1615        SwsContext *c2;
1616        c->cascaded_context[0] = NULL;
1617
1618        ret = av_image_alloc(c->cascaded_tmp, c->cascaded_tmpStride,
1619                            srcW, srcH, tmpFmt, 64);
1620        if (ret < 0)
1621            return ret;
1622
1623        c->cascaded_context[0] = sws_getContext(srcW, srcH, srcFormat,
1624                                                srcW, srcH, tmpFmt,
1625                                                flags, NULL, NULL, c->param);
1626        if (!c->cascaded_context[0]) {
1627            return AVERROR(ENOMEM);
1628        }
1629
1630        c->cascaded_context[1] = sws_getContext(srcW, srcH, tmpFmt,
1631                                                dstW, dstH, tmpFmt,
1632                                                flags, srcFilter, dstFilter, c->param);
1633
1634        if (!c->cascaded_context[1])
1635            return AVERROR(ENOMEM);
1636
1637        c2 = c->cascaded_context[1];
1638        c2->is_internal_gamma = 1;
1639        c2->gamma     = alloc_gamma_tbl(    c->gamma_value);
1640        c2->inv_gamma = alloc_gamma_tbl(1.f/c->gamma_value);
1641        if (!c2->gamma || !c2->inv_gamma)
1642            return AVERROR(ENOMEM);
1643
1644        // is_internal_flag is set after creating the context
1645        // to properly create the gamma convert FilterDescriptor
1646        // we have to re-initialize it
1647        ff_free_filters(c2);
1648        if ((ret = ff_init_filters(c2)) < 0) {
1649            sws_freeContext(c2);
1650            c->cascaded_context[1] = NULL;
1651            return ret;
1652        }
1653
1654        c->cascaded_context[2] = NULL;
1655        if (dstFormat != tmpFmt) {
1656            ret = av_image_alloc(c->cascaded1_tmp, c->cascaded1_tmpStride,
1657                                dstW, dstH, tmpFmt, 64);
1658            if (ret < 0)
1659                return ret;
1660
1661            c->cascaded_context[2] = sws_getContext(dstW, dstH, tmpFmt,
1662                                                dstW, dstH, dstFormat,
1663                                                flags, NULL, NULL, c->param);
1664            if (!c->cascaded_context[2])
1665                return AVERROR(ENOMEM);
1666        }
1667        return 0;
1668    }
1669
1670    if (isBayer(srcFormat)) {
1671        if (!unscaled ||
1672            (dstFormat != AV_PIX_FMT_RGB24 && dstFormat != AV_PIX_FMT_YUV420P &&
1673             dstFormat != AV_PIX_FMT_RGB48)) {
1674            enum AVPixelFormat tmpFormat = isBayer16BPS(srcFormat) ? AV_PIX_FMT_RGB48 : AV_PIX_FMT_RGB24;
1675
1676            ret = av_image_alloc(c->cascaded_tmp, c->cascaded_tmpStride,
1677                                srcW, srcH, tmpFormat, 64);
1678            if (ret < 0)
1679                return ret;
1680
1681            c->cascaded_context[0] = sws_getContext(srcW, srcH, srcFormat,
1682                                                    srcW, srcH, tmpFormat,
1683                                                    flags, srcFilter, NULL, c->param);
1684            if (!c->cascaded_context[0])
1685                return AVERROR(ENOMEM);
1686
1687            c->cascaded_context[1] = sws_getContext(srcW, srcH, tmpFormat,
1688                                                    dstW, dstH, dstFormat,
1689                                                    flags, NULL, dstFilter, c->param);
1690            if (!c->cascaded_context[1])
1691                return AVERROR(ENOMEM);
1692            return 0;
1693        }
1694    }
1695
1696    if (unscaled && c->srcBpc == 8 && dstFormat == AV_PIX_FMT_GRAYF32){
1697        for (i = 0; i < 256; ++i){
1698            c->uint2float_lut[i] = (float)i * float_mult;
1699        }
1700    }
1701
1702    // float will be converted to uint16_t
1703    if ((srcFormat == AV_PIX_FMT_GRAYF32BE || srcFormat == AV_PIX_FMT_GRAYF32LE) &&
1704        (!unscaled || unscaled && dstFormat != srcFormat && (srcFormat != AV_PIX_FMT_GRAYF32 ||
1705        dstFormat != AV_PIX_FMT_GRAY8))){
1706        c->srcBpc = 16;
1707    }
1708
1709    if (CONFIG_SWSCALE_ALPHA && isALPHA(srcFormat) && !isALPHA(dstFormat)) {
1710        enum AVPixelFormat tmpFormat = alphaless_fmt(srcFormat);
1711
1712        if (tmpFormat != AV_PIX_FMT_NONE && c->alphablend != SWS_ALPHA_BLEND_NONE) {
1713            if (!unscaled ||
1714                dstFormat != tmpFormat ||
1715                usesHFilter || usesVFilter ||
1716                c->srcRange != c->dstRange
1717            ) {
1718                c->cascaded_mainindex = 1;
1719                ret = av_image_alloc(c->cascaded_tmp, c->cascaded_tmpStride,
1720                                     srcW, srcH, tmpFormat, 64);
1721                if (ret < 0)
1722                    return ret;
1723
1724                c->cascaded_context[0] = sws_alloc_set_opts(srcW, srcH, srcFormat,
1725                                                            srcW, srcH, tmpFormat,
1726                                                            flags, c->param);
1727                if (!c->cascaded_context[0])
1728                    return AVERROR(EINVAL);
1729                c->cascaded_context[0]->alphablend = c->alphablend;
1730                ret = sws_init_context(c->cascaded_context[0], NULL , NULL);
1731                if (ret < 0)
1732                    return ret;
1733
1734                c->cascaded_context[1] = sws_alloc_set_opts(srcW, srcH, tmpFormat,
1735                                                            dstW, dstH, dstFormat,
1736                                                            flags, c->param);
1737                if (!c->cascaded_context[1])
1738                    return AVERROR(EINVAL);
1739
1740                c->cascaded_context[1]->srcRange = c->srcRange;
1741                c->cascaded_context[1]->dstRange = c->dstRange;
1742                ret = sws_init_context(c->cascaded_context[1], srcFilter , dstFilter);
1743                if (ret < 0)
1744                    return ret;
1745
1746                return 0;
1747            }
1748        }
1749    }
1750
1751#if HAVE_MMAP && HAVE_MPROTECT && defined(MAP_ANONYMOUS)
1752#define USE_MMAP 1
1753#else
1754#define USE_MMAP 0
1755#endif
1756
1757    /* precalculate horizontal scaler filter coefficients */
1758    {
1759#if HAVE_MMXEXT_INLINE
1760// can't downscale !!!
1761        if (c->canMMXEXTBeUsed && (flags & SWS_FAST_BILINEAR)) {
1762            c->lumMmxextFilterCodeSize = ff_init_hscaler_mmxext(dstW, c->lumXInc, NULL,
1763                                                             NULL, NULL, 8);
1764            c->chrMmxextFilterCodeSize = ff_init_hscaler_mmxext(c->chrDstW, c->chrXInc,
1765                                                             NULL, NULL, NULL, 4);
1766
1767#if USE_MMAP
1768            c->lumMmxextFilterCode = mmap(NULL, c->lumMmxextFilterCodeSize,
1769                                          PROT_READ | PROT_WRITE,
1770                                          MAP_PRIVATE | MAP_ANONYMOUS,
1771                                          -1, 0);
1772            c->chrMmxextFilterCode = mmap(NULL, c->chrMmxextFilterCodeSize,
1773                                          PROT_READ | PROT_WRITE,
1774                                          MAP_PRIVATE | MAP_ANONYMOUS,
1775                                          -1, 0);
1776#elif HAVE_VIRTUALALLOC
1777            c->lumMmxextFilterCode = VirtualAlloc(NULL,
1778                                                  c->lumMmxextFilterCodeSize,
1779                                                  MEM_COMMIT,
1780                                                  PAGE_EXECUTE_READWRITE);
1781            c->chrMmxextFilterCode = VirtualAlloc(NULL,
1782                                                  c->chrMmxextFilterCodeSize,
1783                                                  MEM_COMMIT,
1784                                                  PAGE_EXECUTE_READWRITE);
1785#else
1786            c->lumMmxextFilterCode = av_malloc(c->lumMmxextFilterCodeSize);
1787            c->chrMmxextFilterCode = av_malloc(c->chrMmxextFilterCodeSize);
1788#endif
1789
1790#ifdef MAP_ANONYMOUS
1791            if (c->lumMmxextFilterCode == MAP_FAILED || c->chrMmxextFilterCode == MAP_FAILED)
1792#else
1793            if (!c->lumMmxextFilterCode || !c->chrMmxextFilterCode)
1794#endif
1795            {
1796                av_log(c, AV_LOG_ERROR, "Failed to allocate MMX2FilterCode\n");
1797                return AVERROR(ENOMEM);
1798            }
1799
1800            if (!FF_ALLOCZ_TYPED_ARRAY(c->hLumFilter,    dstW           / 8 + 8) ||
1801                !FF_ALLOCZ_TYPED_ARRAY(c->hChrFilter,    c->chrDstW     / 4 + 8) ||
1802                !FF_ALLOCZ_TYPED_ARRAY(c->hLumFilterPos, dstW       / 2 / 8 + 8) ||
1803                !FF_ALLOCZ_TYPED_ARRAY(c->hChrFilterPos, c->chrDstW / 2 / 4 + 8))
1804                goto nomem;
1805
1806            ff_init_hscaler_mmxext(      dstW, c->lumXInc, c->lumMmxextFilterCode,
1807                                c->hLumFilter, (uint32_t*)c->hLumFilterPos, 8);
1808            ff_init_hscaler_mmxext(c->chrDstW, c->chrXInc, c->chrMmxextFilterCode,
1809                                c->hChrFilter, (uint32_t*)c->hChrFilterPos, 4);
1810
1811#if USE_MMAP
1812            if (   mprotect(c->lumMmxextFilterCode, c->lumMmxextFilterCodeSize, PROT_EXEC | PROT_READ) == -1
1813                || mprotect(c->chrMmxextFilterCode, c->chrMmxextFilterCodeSize, PROT_EXEC | PROT_READ) == -1) {
1814                av_log(c, AV_LOG_ERROR, "mprotect failed, cannot use fast bilinear scaler\n");
1815                ret = AVERROR(EINVAL);
1816                goto fail;
1817            }
1818#endif
1819        } else
1820#endif /* HAVE_MMXEXT_INLINE */
1821        {
1822            const int filterAlign = X86_MMX(cpu_flags)     ? 4 :
1823                                    PPC_ALTIVEC(cpu_flags) ? 8 :
1824                                    have_neon(cpu_flags)   ? 4 : 1;
1825
1826            if ((ret = initFilter(&c->hLumFilter, &c->hLumFilterPos,
1827                           &c->hLumFilterSize, c->lumXInc,
1828                           srcW, dstW, filterAlign, 1 << 14,
1829                           (flags & SWS_BICUBLIN) ? (flags | SWS_BICUBIC) : flags,
1830                           cpu_flags, srcFilter->lumH, dstFilter->lumH,
1831                           c->param,
1832                           get_local_pos(c, 0, 0, 0),
1833                           get_local_pos(c, 0, 0, 0))) < 0)
1834                goto fail;
1835            if (ff_shuffle_filter_coefficients(c, c->hLumFilterPos, c->hLumFilterSize, c->hLumFilter, dstW) < 0)
1836                goto nomem;
1837            if ((ret = initFilter(&c->hChrFilter, &c->hChrFilterPos,
1838                           &c->hChrFilterSize, c->chrXInc,
1839                           c->chrSrcW, c->chrDstW, filterAlign, 1 << 14,
1840                           (flags & SWS_BICUBLIN) ? (flags | SWS_BILINEAR) : flags,
1841                           cpu_flags, srcFilter->chrH, dstFilter->chrH,
1842                           c->param,
1843                           get_local_pos(c, c->chrSrcHSubSample, c->src_h_chr_pos, 0),
1844                           get_local_pos(c, c->chrDstHSubSample, c->dst_h_chr_pos, 0))) < 0)
1845                goto fail;
1846            if (ff_shuffle_filter_coefficients(c, c->hChrFilterPos, c->hChrFilterSize, c->hChrFilter, c->chrDstW) < 0)
1847                goto nomem;
1848        }
1849    } // initialize horizontal stuff
1850
1851    /* precalculate vertical scaler filter coefficients */
1852    {
1853        const int filterAlign = X86_MMX(cpu_flags)     ? 2 :
1854                                PPC_ALTIVEC(cpu_flags) ? 8 :
1855                                have_neon(cpu_flags)   ? 2 : 1;
1856
1857        if ((ret = initFilter(&c->vLumFilter, &c->vLumFilterPos, &c->vLumFilterSize,
1858                       c->lumYInc, srcH, dstH, filterAlign, (1 << 12),
1859                       (flags & SWS_BICUBLIN) ? (flags | SWS_BICUBIC) : flags,
1860                       cpu_flags, srcFilter->lumV, dstFilter->lumV,
1861                       c->param,
1862                       get_local_pos(c, 0, 0, 1),
1863                       get_local_pos(c, 0, 0, 1))) < 0)
1864            goto fail;
1865        if ((ret = initFilter(&c->vChrFilter, &c->vChrFilterPos, &c->vChrFilterSize,
1866                       c->chrYInc, c->chrSrcH, c->chrDstH,
1867                       filterAlign, (1 << 12),
1868                       (flags & SWS_BICUBLIN) ? (flags | SWS_BILINEAR) : flags,
1869                       cpu_flags, srcFilter->chrV, dstFilter->chrV,
1870                       c->param,
1871                       get_local_pos(c, c->chrSrcVSubSample, c->src_v_chr_pos, 1),
1872                       get_local_pos(c, c->chrDstVSubSample, c->dst_v_chr_pos, 1))) < 0)
1873
1874            goto fail;
1875
1876#if HAVE_ALTIVEC
1877        if (!FF_ALLOC_TYPED_ARRAY(c->vYCoeffsBank, c->vLumFilterSize * c->dstH) ||
1878            !FF_ALLOC_TYPED_ARRAY(c->vCCoeffsBank, c->vChrFilterSize * c->chrDstH))
1879            goto nomem;
1880
1881        for (i = 0; i < c->vLumFilterSize * c->dstH; i++) {
1882            int j;
1883            short *p = (short *)&c->vYCoeffsBank[i];
1884            for (j = 0; j < 8; j++)
1885                p[j] = c->vLumFilter[i];
1886        }
1887
1888        for (i = 0; i < c->vChrFilterSize * c->chrDstH; i++) {
1889            int j;
1890            short *p = (short *)&c->vCCoeffsBank[i];
1891            for (j = 0; j < 8; j++)
1892                p[j] = c->vChrFilter[i];
1893        }
1894#endif
1895    }
1896
1897    for (i = 0; i < 4; i++)
1898        if (!FF_ALLOCZ_TYPED_ARRAY(c->dither_error[i], c->dstW + 2))
1899            goto nomem;
1900
1901    c->needAlpha = (CONFIG_SWSCALE_ALPHA && isALPHA(c->srcFormat) && isALPHA(c->dstFormat)) ? 1 : 0;
1902
1903    // 64 / c->scalingBpp is the same as 16 / sizeof(scaling_intermediate)
1904    c->uv_off   = (dst_stride>>1) + 64 / (c->dstBpc &~ 7);
1905    c->uv_offx2 = dst_stride + 16;
1906
1907    av_assert0(c->chrDstH <= dstH);
1908
1909    if (flags & SWS_PRINT_INFO) {
1910        const char *scaler = NULL, *cpucaps;
1911
1912        for (i = 0; i < FF_ARRAY_ELEMS(scale_algorithms); i++) {
1913            if (flags & scale_algorithms[i].flag) {
1914                scaler = scale_algorithms[i].description;
1915                break;
1916            }
1917        }
1918        if (!scaler)
1919            scaler =  "ehh flags invalid?!";
1920        av_log(c, AV_LOG_INFO, "%s scaler, from %s to %s%s ",
1921               scaler,
1922               av_get_pix_fmt_name(srcFormat),
1923#ifdef DITHER1XBPP
1924               dstFormat == AV_PIX_FMT_BGR555   || dstFormat == AV_PIX_FMT_BGR565   ||
1925               dstFormat == AV_PIX_FMT_RGB444BE || dstFormat == AV_PIX_FMT_RGB444LE ||
1926               dstFormat == AV_PIX_FMT_BGR444BE || dstFormat == AV_PIX_FMT_BGR444LE ?
1927                                                             "dithered " : "",
1928#else
1929               "",
1930#endif
1931               av_get_pix_fmt_name(dstFormat));
1932
1933        if (INLINE_MMXEXT(cpu_flags))
1934            cpucaps = "MMXEXT";
1935        else if (INLINE_AMD3DNOW(cpu_flags))
1936            cpucaps = "3DNOW";
1937        else if (INLINE_MMX(cpu_flags))
1938            cpucaps = "MMX";
1939        else if (PPC_ALTIVEC(cpu_flags))
1940            cpucaps = "AltiVec";
1941        else
1942            cpucaps = "C";
1943
1944        av_log(c, AV_LOG_INFO, "using %s\n", cpucaps);
1945
1946        av_log(c, AV_LOG_VERBOSE, "%dx%d -> %dx%d\n", srcW, srcH, dstW, dstH);
1947        av_log(c, AV_LOG_DEBUG,
1948               "lum srcW=%d srcH=%d dstW=%d dstH=%d xInc=%d yInc=%d\n",
1949               c->srcW, c->srcH, c->dstW, c->dstH, c->lumXInc, c->lumYInc);
1950        av_log(c, AV_LOG_DEBUG,
1951               "chr srcW=%d srcH=%d dstW=%d dstH=%d xInc=%d yInc=%d\n",
1952               c->chrSrcW, c->chrSrcH, c->chrDstW, c->chrDstH,
1953               c->chrXInc, c->chrYInc);
1954    }
1955
1956    /* alpha blend special case, note this has been split via cascaded contexts if its scaled */
1957    if (unscaled && !usesHFilter && !usesVFilter &&
1958        c->alphablend != SWS_ALPHA_BLEND_NONE &&
1959        isALPHA(srcFormat) &&
1960        (c->srcRange == c->dstRange || isAnyRGB(dstFormat)) &&
1961        alphaless_fmt(srcFormat) == dstFormat
1962    ) {
1963        c->convert_unscaled = ff_sws_alphablendaway;
1964
1965        if (flags & SWS_PRINT_INFO)
1966            av_log(c, AV_LOG_INFO,
1967                    "using alpha blendaway %s -> %s special converter\n",
1968                    av_get_pix_fmt_name(srcFormat), av_get_pix_fmt_name(dstFormat));
1969        return 0;
1970    }
1971
1972    /* unscaled special cases */
1973    if (unscaled && !usesHFilter && !usesVFilter &&
1974        (c->srcRange == c->dstRange || isAnyRGB(dstFormat) ||
1975         isFloat(srcFormat) || isFloat(dstFormat) || isBayer(srcFormat))){
1976        ff_get_unscaled_swscale(c);
1977
1978        if (c->convert_unscaled) {
1979            if (flags & SWS_PRINT_INFO)
1980                av_log(c, AV_LOG_INFO,
1981                       "using unscaled %s -> %s special converter\n",
1982                       av_get_pix_fmt_name(srcFormat), av_get_pix_fmt_name(dstFormat));
1983            return 0;
1984        }
1985    }
1986
1987    ff_sws_init_scale(c);
1988
1989    return ff_init_filters(c);
1990nomem:
1991    ret = AVERROR(ENOMEM);
1992fail: // FIXME replace things by appropriate error codes
1993    if (ret == RETCODE_USE_CASCADE)  {
1994        int tmpW = sqrt(srcW * (int64_t)dstW);
1995        int tmpH = sqrt(srcH * (int64_t)dstH);
1996        enum AVPixelFormat tmpFormat = AV_PIX_FMT_YUV420P;
1997
1998        if (isALPHA(srcFormat))
1999            tmpFormat = AV_PIX_FMT_YUVA420P;
2000
2001        if (srcW*(int64_t)srcH <= 4LL*dstW*dstH)
2002            return AVERROR(EINVAL);
2003
2004        ret = av_image_alloc(c->cascaded_tmp, c->cascaded_tmpStride,
2005                             tmpW, tmpH, tmpFormat, 64);
2006        if (ret < 0)
2007            return ret;
2008
2009        c->cascaded_context[0] = sws_getContext(srcW, srcH, srcFormat,
2010                                                tmpW, tmpH, tmpFormat,
2011                                                flags, srcFilter, NULL, c->param);
2012        if (!c->cascaded_context[0])
2013            return AVERROR(ENOMEM);
2014
2015        c->cascaded_context[1] = sws_getContext(tmpW, tmpH, tmpFormat,
2016                                                dstW, dstH, dstFormat,
2017                                                flags, NULL, dstFilter, c->param);
2018        if (!c->cascaded_context[1])
2019            return AVERROR(ENOMEM);
2020        return 0;
2021    }
2022    return ret;
2023}
2024
2025SwsContext *sws_alloc_set_opts(int srcW, int srcH, enum AVPixelFormat srcFormat,
2026                               int dstW, int dstH, enum AVPixelFormat dstFormat,
2027                               int flags, const double *param)
2028{
2029    SwsContext *c;
2030
2031    if (!(c = sws_alloc_context()))
2032        return NULL;
2033
2034    c->flags     = flags;
2035    c->srcW      = srcW;
2036    c->srcH      = srcH;
2037    c->dstW      = dstW;
2038    c->dstH      = dstH;
2039    c->srcFormat = srcFormat;
2040    c->dstFormat = dstFormat;
2041
2042    if (param) {
2043        c->param[0] = param[0];
2044        c->param[1] = param[1];
2045    }
2046
2047    return c;
2048}
2049
2050SwsContext *sws_getContext(int srcW, int srcH, enum AVPixelFormat srcFormat,
2051                           int dstW, int dstH, enum AVPixelFormat dstFormat,
2052                           int flags, SwsFilter *srcFilter,
2053                           SwsFilter *dstFilter, const double *param)
2054{
2055    SwsContext *c;
2056
2057    c = sws_alloc_set_opts(srcW, srcH, srcFormat,
2058                           dstW, dstH, dstFormat,
2059                           flags, param);
2060    if (!c)
2061        return NULL;
2062
2063    if (sws_init_context(c, srcFilter, dstFilter) < 0) {
2064        sws_freeContext(c);
2065        return NULL;
2066    }
2067
2068    return c;
2069}
2070
2071static int isnan_vec(SwsVector *a)
2072{
2073    int i;
2074    for (i=0; i<a->length; i++)
2075        if (isnan(a->coeff[i]))
2076            return 1;
2077    return 0;
2078}
2079
2080static void makenan_vec(SwsVector *a)
2081{
2082    int i;
2083    for (i=0; i<a->length; i++)
2084        a->coeff[i] = NAN;
2085}
2086
2087SwsFilter *sws_getDefaultFilter(float lumaGBlur, float chromaGBlur,
2088                                float lumaSharpen, float chromaSharpen,
2089                                float chromaHShift, float chromaVShift,
2090                                int verbose)
2091{
2092    SwsFilter *filter = av_malloc(sizeof(SwsFilter));
2093    if (!filter)
2094        return NULL;
2095
2096    if (lumaGBlur != 0.0) {
2097        filter->lumH = sws_getGaussianVec(lumaGBlur, 3.0);
2098        filter->lumV = sws_getGaussianVec(lumaGBlur, 3.0);
2099    } else {
2100        filter->lumH = sws_getIdentityVec();
2101        filter->lumV = sws_getIdentityVec();
2102    }
2103
2104    if (chromaGBlur != 0.0) {
2105        filter->chrH = sws_getGaussianVec(chromaGBlur, 3.0);
2106        filter->chrV = sws_getGaussianVec(chromaGBlur, 3.0);
2107    } else {
2108        filter->chrH = sws_getIdentityVec();
2109        filter->chrV = sws_getIdentityVec();
2110    }
2111
2112    if (!filter->lumH || !filter->lumV || !filter->chrH || !filter->chrV)
2113        goto fail;
2114
2115    if (chromaSharpen != 0.0) {
2116        SwsVector *id = sws_getIdentityVec();
2117        if (!id)
2118            goto fail;
2119        sws_scaleVec(filter->chrH, -chromaSharpen);
2120        sws_scaleVec(filter->chrV, -chromaSharpen);
2121        sws_addVec(filter->chrH, id);
2122        sws_addVec(filter->chrV, id);
2123        sws_freeVec(id);
2124    }
2125
2126    if (lumaSharpen != 0.0) {
2127        SwsVector *id = sws_getIdentityVec();
2128        if (!id)
2129            goto fail;
2130        sws_scaleVec(filter->lumH, -lumaSharpen);
2131        sws_scaleVec(filter->lumV, -lumaSharpen);
2132        sws_addVec(filter->lumH, id);
2133        sws_addVec(filter->lumV, id);
2134        sws_freeVec(id);
2135    }
2136
2137    if (chromaHShift != 0.0)
2138        sws_shiftVec(filter->chrH, (int)(chromaHShift + 0.5));
2139
2140    if (chromaVShift != 0.0)
2141        sws_shiftVec(filter->chrV, (int)(chromaVShift + 0.5));
2142
2143    sws_normalizeVec(filter->chrH, 1.0);
2144    sws_normalizeVec(filter->chrV, 1.0);
2145    sws_normalizeVec(filter->lumH, 1.0);
2146    sws_normalizeVec(filter->lumV, 1.0);
2147
2148    if (isnan_vec(filter->chrH) ||
2149        isnan_vec(filter->chrV) ||
2150        isnan_vec(filter->lumH) ||
2151        isnan_vec(filter->lumV))
2152        goto fail;
2153
2154    if (verbose)
2155        sws_printVec2(filter->chrH, NULL, AV_LOG_DEBUG);
2156    if (verbose)
2157        sws_printVec2(filter->lumH, NULL, AV_LOG_DEBUG);
2158
2159    return filter;
2160
2161fail:
2162    sws_freeVec(filter->lumH);
2163    sws_freeVec(filter->lumV);
2164    sws_freeVec(filter->chrH);
2165    sws_freeVec(filter->chrV);
2166    av_freep(&filter);
2167    return NULL;
2168}
2169
2170SwsVector *sws_allocVec(int length)
2171{
2172    SwsVector *vec;
2173
2174    if(length <= 0 || length > INT_MAX/ sizeof(double))
2175        return NULL;
2176
2177    vec = av_malloc(sizeof(SwsVector));
2178    if (!vec)
2179        return NULL;
2180    vec->length = length;
2181    vec->coeff  = av_malloc(sizeof(double) * length);
2182    if (!vec->coeff)
2183        av_freep(&vec);
2184    return vec;
2185}
2186
2187SwsVector *sws_getGaussianVec(double variance, double quality)
2188{
2189    const int length = (int)(variance * quality + 0.5) | 1;
2190    int i;
2191    double middle  = (length - 1) * 0.5;
2192    SwsVector *vec;
2193
2194    if(variance < 0 || quality < 0)
2195        return NULL;
2196
2197    vec = sws_allocVec(length);
2198
2199    if (!vec)
2200        return NULL;
2201
2202    for (i = 0; i < length; i++) {
2203        double dist = i - middle;
2204        vec->coeff[i] = exp(-dist * dist / (2 * variance * variance)) /
2205                        sqrt(2 * variance * M_PI);
2206    }
2207
2208    sws_normalizeVec(vec, 1.0);
2209
2210    return vec;
2211}
2212
2213/**
2214 * Allocate and return a vector with length coefficients, all
2215 * with the same value c.
2216 */
2217static
2218SwsVector *sws_getConstVec(double c, int length)
2219{
2220    int i;
2221    SwsVector *vec = sws_allocVec(length);
2222
2223    if (!vec)
2224        return NULL;
2225
2226    for (i = 0; i < length; i++)
2227        vec->coeff[i] = c;
2228
2229    return vec;
2230}
2231
2232/**
2233 * Allocate and return a vector with just one coefficient, with
2234 * value 1.0.
2235 */
2236static
2237SwsVector *sws_getIdentityVec(void)
2238{
2239    return sws_getConstVec(1.0, 1);
2240}
2241
2242static double sws_dcVec(SwsVector *a)
2243{
2244    int i;
2245    double sum = 0;
2246
2247    for (i = 0; i < a->length; i++)
2248        sum += a->coeff[i];
2249
2250    return sum;
2251}
2252
2253void sws_scaleVec(SwsVector *a, double scalar)
2254{
2255    int i;
2256
2257    for (i = 0; i < a->length; i++)
2258        a->coeff[i] *= scalar;
2259}
2260
2261void sws_normalizeVec(SwsVector *a, double height)
2262{
2263    sws_scaleVec(a, height / sws_dcVec(a));
2264}
2265
2266static SwsVector *sws_sumVec(SwsVector *a, SwsVector *b)
2267{
2268    int length = FFMAX(a->length, b->length);
2269    int i;
2270    SwsVector *vec = sws_getConstVec(0.0, length);
2271
2272    if (!vec)
2273        return NULL;
2274
2275    for (i = 0; i < a->length; i++)
2276        vec->coeff[i + (length - 1) / 2 - (a->length - 1) / 2] += a->coeff[i];
2277    for (i = 0; i < b->length; i++)
2278        vec->coeff[i + (length - 1) / 2 - (b->length - 1) / 2] += b->coeff[i];
2279
2280    return vec;
2281}
2282
2283/* shift left / or right if "shift" is negative */
2284static SwsVector *sws_getShiftedVec(SwsVector *a, int shift)
2285{
2286    int length = a->length + FFABS(shift) * 2;
2287    int i;
2288    SwsVector *vec = sws_getConstVec(0.0, length);
2289
2290    if (!vec)
2291        return NULL;
2292
2293    for (i = 0; i < a->length; i++) {
2294        vec->coeff[i + (length    - 1) / 2 -
2295                       (a->length - 1) / 2 - shift] = a->coeff[i];
2296    }
2297
2298    return vec;
2299}
2300
2301static
2302void sws_shiftVec(SwsVector *a, int shift)
2303{
2304    SwsVector *shifted = sws_getShiftedVec(a, shift);
2305    if (!shifted) {
2306        makenan_vec(a);
2307        return;
2308    }
2309    av_free(a->coeff);
2310    a->coeff  = shifted->coeff;
2311    a->length = shifted->length;
2312    av_free(shifted);
2313}
2314
2315static
2316void sws_addVec(SwsVector *a, SwsVector *b)
2317{
2318    SwsVector *sum = sws_sumVec(a, b);
2319    if (!sum) {
2320        makenan_vec(a);
2321        return;
2322    }
2323    av_free(a->coeff);
2324    a->coeff  = sum->coeff;
2325    a->length = sum->length;
2326    av_free(sum);
2327}
2328
2329/**
2330 * Print with av_log() a textual representation of the vector a
2331 * if log_level <= av_log_level.
2332 */
2333static
2334void sws_printVec2(SwsVector *a, AVClass *log_ctx, int log_level)
2335{
2336    int i;
2337    double max = 0;
2338    double min = 0;
2339    double range;
2340
2341    for (i = 0; i < a->length; i++)
2342        if (a->coeff[i] > max)
2343            max = a->coeff[i];
2344
2345    for (i = 0; i < a->length; i++)
2346        if (a->coeff[i] < min)
2347            min = a->coeff[i];
2348
2349    range = max - min;
2350
2351    for (i = 0; i < a->length; i++) {
2352        int x = (int)((a->coeff[i] - min) * 60.0 / range + 0.5);
2353        av_log(log_ctx, log_level, "%1.3f ", a->coeff[i]);
2354        for (; x > 0; x--)
2355            av_log(log_ctx, log_level, " ");
2356        av_log(log_ctx, log_level, "|\n");
2357    }
2358}
2359
2360void sws_freeVec(SwsVector *a)
2361{
2362    if (!a)
2363        return;
2364    av_freep(&a->coeff);
2365    a->length = 0;
2366    av_free(a);
2367}
2368
2369void sws_freeFilter(SwsFilter *filter)
2370{
2371    if (!filter)
2372        return;
2373
2374    sws_freeVec(filter->lumH);
2375    sws_freeVec(filter->lumV);
2376    sws_freeVec(filter->chrH);
2377    sws_freeVec(filter->chrV);
2378    av_free(filter);
2379}
2380
2381void sws_freeContext(SwsContext *c)
2382{
2383    int i;
2384    if (!c)
2385        return;
2386
2387    for (i = 0; i < c->nb_slice_ctx; i++)
2388        sws_freeContext(c->slice_ctx[i]);
2389    av_freep(&c->slice_ctx);
2390    av_freep(&c->slice_err);
2391
2392    avpriv_slicethread_free(&c->slicethread);
2393
2394    for (i = 0; i < 4; i++)
2395        av_freep(&c->dither_error[i]);
2396
2397    av_frame_free(&c->frame_src);
2398    av_frame_free(&c->frame_dst);
2399
2400    av_freep(&c->src_ranges.ranges);
2401
2402    av_freep(&c->vLumFilter);
2403    av_freep(&c->vChrFilter);
2404    av_freep(&c->hLumFilter);
2405    av_freep(&c->hChrFilter);
2406#if HAVE_ALTIVEC
2407    av_freep(&c->vYCoeffsBank);
2408    av_freep(&c->vCCoeffsBank);
2409#endif
2410
2411    av_freep(&c->vLumFilterPos);
2412    av_freep(&c->vChrFilterPos);
2413    av_freep(&c->hLumFilterPos);
2414    av_freep(&c->hChrFilterPos);
2415
2416#if HAVE_MMX_INLINE
2417#if USE_MMAP
2418    if (c->lumMmxextFilterCode)
2419        munmap(c->lumMmxextFilterCode, c->lumMmxextFilterCodeSize);
2420    if (c->chrMmxextFilterCode)
2421        munmap(c->chrMmxextFilterCode, c->chrMmxextFilterCodeSize);
2422#elif HAVE_VIRTUALALLOC
2423    if (c->lumMmxextFilterCode)
2424        VirtualFree(c->lumMmxextFilterCode, 0, MEM_RELEASE);
2425    if (c->chrMmxextFilterCode)
2426        VirtualFree(c->chrMmxextFilterCode, 0, MEM_RELEASE);
2427#else
2428    av_free(c->lumMmxextFilterCode);
2429    av_free(c->chrMmxextFilterCode);
2430#endif
2431    c->lumMmxextFilterCode = NULL;
2432    c->chrMmxextFilterCode = NULL;
2433#endif /* HAVE_MMX_INLINE */
2434
2435    av_freep(&c->yuvTable);
2436    av_freep(&c->formatConvBuffer);
2437
2438    sws_freeContext(c->cascaded_context[0]);
2439    sws_freeContext(c->cascaded_context[1]);
2440    sws_freeContext(c->cascaded_context[2]);
2441    memset(c->cascaded_context, 0, sizeof(c->cascaded_context));
2442    av_freep(&c->cascaded_tmp[0]);
2443    av_freep(&c->cascaded1_tmp[0]);
2444
2445    av_freep(&c->gamma);
2446    av_freep(&c->inv_gamma);
2447
2448    av_freep(&c->rgb0_scratch);
2449    av_freep(&c->xyz_scratch);
2450
2451    ff_free_filters(c);
2452
2453    av_free(c);
2454}
2455
2456struct SwsContext *sws_getCachedContext(struct SwsContext *context, int srcW,
2457                                        int srcH, enum AVPixelFormat srcFormat,
2458                                        int dstW, int dstH,
2459                                        enum AVPixelFormat dstFormat, int flags,
2460                                        SwsFilter *srcFilter,
2461                                        SwsFilter *dstFilter,
2462                                        const double *param)
2463{
2464    static const double default_param[2] = { SWS_PARAM_DEFAULT,
2465                                             SWS_PARAM_DEFAULT };
2466    int64_t src_h_chr_pos = -513, dst_h_chr_pos = -513,
2467            src_v_chr_pos = -513, dst_v_chr_pos = -513;
2468
2469    if (!param)
2470        param = default_param;
2471
2472    if (context &&
2473        (context->srcW      != srcW      ||
2474         context->srcH      != srcH      ||
2475         context->srcFormat != srcFormat ||
2476         context->dstW      != dstW      ||
2477         context->dstH      != dstH      ||
2478         context->dstFormat != dstFormat ||
2479         context->flags     != flags     ||
2480         context->param[0]  != param[0]  ||
2481         context->param[1]  != param[1])) {
2482
2483        av_opt_get_int(context, "src_h_chr_pos", 0, &src_h_chr_pos);
2484        av_opt_get_int(context, "src_v_chr_pos", 0, &src_v_chr_pos);
2485        av_opt_get_int(context, "dst_h_chr_pos", 0, &dst_h_chr_pos);
2486        av_opt_get_int(context, "dst_v_chr_pos", 0, &dst_v_chr_pos);
2487        sws_freeContext(context);
2488        context = NULL;
2489    }
2490
2491    if (!context) {
2492        if (!(context = sws_alloc_context()))
2493            return NULL;
2494        context->srcW      = srcW;
2495        context->srcH      = srcH;
2496        context->srcFormat = srcFormat;
2497        context->dstW      = dstW;
2498        context->dstH      = dstH;
2499        context->dstFormat = dstFormat;
2500        context->flags     = flags;
2501        context->param[0]  = param[0];
2502        context->param[1]  = param[1];
2503
2504        av_opt_set_int(context, "src_h_chr_pos", src_h_chr_pos, 0);
2505        av_opt_set_int(context, "src_v_chr_pos", src_v_chr_pos, 0);
2506        av_opt_set_int(context, "dst_h_chr_pos", dst_h_chr_pos, 0);
2507        av_opt_set_int(context, "dst_v_chr_pos", dst_v_chr_pos, 0);
2508
2509        if (sws_init_context(context, srcFilter, dstFilter) < 0) {
2510            sws_freeContext(context);
2511            return NULL;
2512        }
2513    }
2514    return context;
2515}
2516
2517int ff_range_add(RangeList *rl, unsigned int start, unsigned int len)
2518{
2519    Range *tmp;
2520    unsigned int idx;
2521
2522    /* find the first existing range after the new one */
2523    for (idx = 0; idx < rl->nb_ranges; idx++)
2524        if (rl->ranges[idx].start > start)
2525            break;
2526
2527    /* check for overlap */
2528    if (idx > 0) {
2529        Range *prev = &rl->ranges[idx - 1];
2530        if (prev->start + prev->len > start)
2531            return AVERROR(EINVAL);
2532    }
2533    if (idx < rl->nb_ranges) {
2534        Range *next = &rl->ranges[idx];
2535        if (start + len > next->start)
2536            return AVERROR(EINVAL);
2537    }
2538
2539    tmp = av_fast_realloc(rl->ranges, &rl->ranges_allocated,
2540                          (rl->nb_ranges + 1) * sizeof(*rl->ranges));
2541    if (!tmp)
2542        return AVERROR(ENOMEM);
2543    rl->ranges = tmp;
2544
2545    memmove(rl->ranges + idx + 1, rl->ranges + idx,
2546            sizeof(*rl->ranges) * (rl->nb_ranges - idx));
2547    rl->ranges[idx].start = start;
2548    rl->ranges[idx].len   = len;
2549    rl->nb_ranges++;
2550
2551    /* merge ranges */
2552    if (idx > 0) {
2553        Range *prev = &rl->ranges[idx - 1];
2554        Range *cur  = &rl->ranges[idx];
2555        if (prev->start + prev->len == cur->start) {
2556            prev->len += cur->len;
2557            memmove(rl->ranges + idx - 1, rl->ranges + idx,
2558                    sizeof(*rl->ranges) * (rl->nb_ranges - idx));
2559            rl->nb_ranges--;
2560            idx--;
2561        }
2562    }
2563    if (idx < rl->nb_ranges - 1) {
2564        Range *cur  = &rl->ranges[idx];
2565        Range *next = &rl->ranges[idx + 1];
2566        if (cur->start + cur->len == next->start) {
2567            cur->len += next->len;
2568            memmove(rl->ranges + idx, rl->ranges + idx + 1,
2569                    sizeof(*rl->ranges) * (rl->nb_ranges - idx - 1));
2570            rl->nb_ranges--;
2571        }
2572    }
2573
2574    return 0;
2575}
2576