1/*
2 * H.264 IDCT
3 * Copyright (c) 2004-2011 Michael Niedermayer <michaelni@gmx.at>
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22/**
23 * @file
24 * H.264 IDCT.
25 * @author Michael Niedermayer <michaelni@gmx.at>
26 */
27
28#include "bit_depth_template.c"
29#include "libavutil/common.h"
30#include "h264dec.h"
31#include "h264idct.h"
32
33void FUNCC(ff_h264_idct_add)(uint8_t *_dst, int16_t *_block, int stride)
34{
35    int i;
36    pixel *dst = (pixel*)_dst;
37    dctcoef *block = (dctcoef*)_block;
38    stride >>= sizeof(pixel)-1;
39
40    block[0] += 1 << 5;
41
42    for(i=0; i<4; i++){
43        const SUINT z0=  block[i + 4*0]     +  (unsigned)block[i + 4*2];
44        const SUINT z1=  block[i + 4*0]     -  (unsigned)block[i + 4*2];
45        const SUINT z2= (block[i + 4*1]>>1) -  (unsigned)block[i + 4*3];
46        const SUINT z3=  block[i + 4*1]     + (unsigned)(block[i + 4*3]>>1);
47
48        block[i + 4*0]= z0 + z3;
49        block[i + 4*1]= z1 + z2;
50        block[i + 4*2]= z1 - z2;
51        block[i + 4*3]= z0 - z3;
52    }
53
54    for(i=0; i<4; i++){
55        const SUINT z0=  block[0 + 4*i]     +  (SUINT)block[2 + 4*i];
56        const SUINT z1=  block[0 + 4*i]     -  (SUINT)block[2 + 4*i];
57        const SUINT z2= (block[1 + 4*i]>>1) -  (SUINT)block[3 + 4*i];
58        const SUINT z3=  block[1 + 4*i]     + (SUINT)(block[3 + 4*i]>>1);
59
60        dst[i + 0*stride]= av_clip_pixel(dst[i + 0*stride] + ((int)(z0 + z3) >> 6));
61        dst[i + 1*stride]= av_clip_pixel(dst[i + 1*stride] + ((int)(z1 + z2) >> 6));
62        dst[i + 2*stride]= av_clip_pixel(dst[i + 2*stride] + ((int)(z1 - z2) >> 6));
63        dst[i + 3*stride]= av_clip_pixel(dst[i + 3*stride] + ((int)(z0 - z3) >> 6));
64    }
65
66    memset(block, 0, 16 * sizeof(dctcoef));
67}
68
69void FUNCC(ff_h264_idct8_add)(uint8_t *_dst, int16_t *_block, int stride){
70    int i;
71    pixel *dst = (pixel*)_dst;
72    dctcoef *block = (dctcoef*)_block;
73    stride >>= sizeof(pixel)-1;
74
75    block[0] += 32;
76
77    for( i = 0; i < 8; i++ )
78    {
79        const unsigned int a0 =  block[i+0*8] + (unsigned)block[i+4*8];
80        const unsigned int a2 =  block[i+0*8] - (unsigned)block[i+4*8];
81        const unsigned int a4 = (block[i+2*8]>>1) - (unsigned)block[i+6*8];
82        const unsigned int a6 = (block[i+6*8]>>1) + (unsigned)block[i+2*8];
83
84        const unsigned int b0 = a0 + a6;
85        const unsigned int b2 = a2 + a4;
86        const unsigned int b4 = a2 - a4;
87        const unsigned int b6 = a0 - a6;
88
89        const int a1 = -block[i+3*8] + (unsigned)block[i+5*8] - block[i+7*8] - (block[i+7*8]>>1);
90        const int a3 =  block[i+1*8] + (unsigned)block[i+7*8] - block[i+3*8] - (block[i+3*8]>>1);
91        const int a5 = -block[i+1*8] + (unsigned)block[i+7*8] + block[i+5*8] + (block[i+5*8]>>1);
92        const int a7 =  block[i+3*8] + (unsigned)block[i+5*8] + block[i+1*8] + (block[i+1*8]>>1);
93
94        const int b1 = (a7>>2) + (unsigned)a1;
95        const int b3 =  (unsigned)a3 + (a5>>2);
96        const int b5 = (a3>>2) - (unsigned)a5;
97        const int b7 =  (unsigned)a7 - (a1>>2);
98
99        block[i+0*8] = b0 + b7;
100        block[i+7*8] = b0 - b7;
101        block[i+1*8] = b2 + b5;
102        block[i+6*8] = b2 - b5;
103        block[i+2*8] = b4 + b3;
104        block[i+5*8] = b4 - b3;
105        block[i+3*8] = b6 + b1;
106        block[i+4*8] = b6 - b1;
107    }
108    for( i = 0; i < 8; i++ )
109    {
110        const unsigned a0 =  block[0+i*8] + (unsigned)block[4+i*8];
111        const unsigned a2 =  block[0+i*8] - (unsigned)block[4+i*8];
112        const unsigned a4 = (block[2+i*8]>>1) - (unsigned)block[6+i*8];
113        const unsigned a6 = (block[6+i*8]>>1) + (unsigned)block[2+i*8];
114
115        const unsigned b0 = a0 + a6;
116        const unsigned b2 = a2 + a4;
117        const unsigned b4 = a2 - a4;
118        const unsigned b6 = a0 - a6;
119
120        const int a1 = -(unsigned)block[3+i*8] + block[5+i*8] - block[7+i*8] - (block[7+i*8]>>1);
121        const int a3 =  (unsigned)block[1+i*8] + block[7+i*8] - block[3+i*8] - (block[3+i*8]>>1);
122        const int a5 = -(unsigned)block[1+i*8] + block[7+i*8] + block[5+i*8] + (block[5+i*8]>>1);
123        const int a7 =  (unsigned)block[3+i*8] + block[5+i*8] + block[1+i*8] + (block[1+i*8]>>1);
124
125        const unsigned b1 = (a7>>2) + (unsigned)a1;
126        const unsigned b3 =  (unsigned)a3 + (a5>>2);
127        const unsigned b5 = (a3>>2) - (unsigned)a5;
128        const unsigned b7 =  (unsigned)a7 - (a1>>2);
129
130        dst[i + 0*stride] = av_clip_pixel( dst[i + 0*stride] + ((int)(b0 + b7) >> 6) );
131        dst[i + 1*stride] = av_clip_pixel( dst[i + 1*stride] + ((int)(b2 + b5) >> 6) );
132        dst[i + 2*stride] = av_clip_pixel( dst[i + 2*stride] + ((int)(b4 + b3) >> 6) );
133        dst[i + 3*stride] = av_clip_pixel( dst[i + 3*stride] + ((int)(b6 + b1) >> 6) );
134        dst[i + 4*stride] = av_clip_pixel( dst[i + 4*stride] + ((int)(b6 - b1) >> 6) );
135        dst[i + 5*stride] = av_clip_pixel( dst[i + 5*stride] + ((int)(b4 - b3) >> 6) );
136        dst[i + 6*stride] = av_clip_pixel( dst[i + 6*stride] + ((int)(b2 - b5) >> 6) );
137        dst[i + 7*stride] = av_clip_pixel( dst[i + 7*stride] + ((int)(b0 - b7) >> 6) );
138    }
139
140    memset(block, 0, 64 * sizeof(dctcoef));
141}
142
143// assumes all AC coefs are 0
144void FUNCC(ff_h264_idct_dc_add)(uint8_t *_dst, int16_t *_block, int stride){
145    int i, j;
146    pixel *dst = (pixel*)_dst;
147    dctcoef *block = (dctcoef*)_block;
148    int dc = (block[0] + 32) >> 6;
149    stride /= sizeof(pixel);
150    block[0] = 0;
151    for( j = 0; j < 4; j++ )
152    {
153        for( i = 0; i < 4; i++ )
154            dst[i] = av_clip_pixel( dst[i] + dc );
155        dst += stride;
156    }
157}
158
159void FUNCC(ff_h264_idct8_dc_add)(uint8_t *_dst, int16_t *_block, int stride){
160    int i, j;
161    pixel *dst = (pixel*)_dst;
162    dctcoef *block = (dctcoef*)_block;
163    int dc = (block[0] + 32) >> 6;
164    block[0] = 0;
165    stride /= sizeof(pixel);
166    for( j = 0; j < 8; j++ )
167    {
168        for( i = 0; i < 8; i++ )
169            dst[i] = av_clip_pixel( dst[i] + dc );
170        dst += stride;
171    }
172}
173
174void FUNCC(ff_h264_idct_add16)(uint8_t *dst, const int *block_offset,
175                               int16_t *block, int stride,
176                               const uint8_t nnzc[5 * 8])
177{
178    int i;
179    for(i=0; i<16; i++){
180        int nnz = nnzc[ scan8[i] ];
181        if(nnz){
182            if(nnz==1 && ((dctcoef*)block)[i*16]) FUNCC(ff_h264_idct_dc_add)(dst + block_offset[i], block + i*16*sizeof(pixel), stride);
183            else                                  FUNCC(ff_h264_idct_add   )(dst + block_offset[i], block + i*16*sizeof(pixel), stride);
184        }
185    }
186}
187
188void FUNCC(ff_h264_idct_add16intra)(uint8_t *dst, const int *block_offset,
189                                    int16_t *block, int stride,
190                                    const uint8_t nnzc[5 * 8])
191{
192    int i;
193    for(i=0; i<16; i++){
194        if(nnzc[ scan8[i] ])             FUNCC(ff_h264_idct_add   )(dst + block_offset[i], block + i*16*sizeof(pixel), stride);
195        else if(((dctcoef*)block)[i*16]) FUNCC(ff_h264_idct_dc_add)(dst + block_offset[i], block + i*16*sizeof(pixel), stride);
196    }
197}
198
199void FUNCC(ff_h264_idct8_add4)(uint8_t *dst, const int *block_offset,
200                               int16_t *block, int stride,
201                               const uint8_t nnzc[5 * 8])
202{
203    int i;
204    for(i=0; i<16; i+=4){
205        int nnz = nnzc[ scan8[i] ];
206        if(nnz){
207            if(nnz==1 && ((dctcoef*)block)[i*16]) FUNCC(ff_h264_idct8_dc_add)(dst + block_offset[i], block + i*16*sizeof(pixel), stride);
208            else                                  FUNCC(ff_h264_idct8_add   )(dst + block_offset[i], block + i*16*sizeof(pixel), stride);
209        }
210    }
211}
212
213void FUNCC(ff_h264_idct_add8)(uint8_t **dest, const int *block_offset, int16_t *block, int stride, const uint8_t nnzc[15*8]){
214    int i, j;
215    for(j=1; j<3; j++){
216        for(i=j*16; i<j*16+4; i++){
217            if(nnzc[ scan8[i] ])
218                FUNCC(ff_h264_idct_add   )(dest[j-1] + block_offset[i], block + i*16*sizeof(pixel), stride);
219            else if(((dctcoef*)block)[i*16])
220                FUNCC(ff_h264_idct_dc_add)(dest[j-1] + block_offset[i], block + i*16*sizeof(pixel), stride);
221        }
222    }
223}
224
225void FUNCC(ff_h264_idct_add8_422)(uint8_t **dest, const int *block_offset, int16_t *block, int stride, const uint8_t nnzc[15*8]){
226    int i, j;
227
228    for(j=1; j<3; j++){
229        for(i=j*16; i<j*16+4; i++){
230            if(nnzc[ scan8[i] ])
231                FUNCC(ff_h264_idct_add   )(dest[j-1] + block_offset[i], block + i*16*sizeof(pixel), stride);
232            else if(((dctcoef*)block)[i*16])
233                FUNCC(ff_h264_idct_dc_add)(dest[j-1] + block_offset[i], block + i*16*sizeof(pixel), stride);
234        }
235    }
236
237    for(j=1; j<3; j++){
238        for(i=j*16+4; i<j*16+8; i++){
239            if(nnzc[ scan8[i+4] ])
240                FUNCC(ff_h264_idct_add   )(dest[j-1] + block_offset[i+4], block + i*16*sizeof(pixel), stride);
241            else if(((dctcoef*)block)[i*16])
242                FUNCC(ff_h264_idct_dc_add)(dest[j-1] + block_offset[i+4], block + i*16*sizeof(pixel), stride);
243        }
244    }
245}
246
247/**
248 * IDCT transforms the 16 dc values and dequantizes them.
249 * @param qmul quantization parameter
250 */
251void FUNCC(ff_h264_luma_dc_dequant_idct)(int16_t *_output, int16_t *_input, int qmul){
252#define stride 16
253    int i;
254    int temp[16];
255    static const uint8_t x_offset[4]={0, 2*stride, 8*stride, 10*stride};
256    dctcoef *input = (dctcoef*)_input;
257    dctcoef *output = (dctcoef*)_output;
258
259    for(i=0; i<4; i++){
260        const int z0= input[4*i+0] + input[4*i+1];
261        const int z1= input[4*i+0] - input[4*i+1];
262        const int z2= input[4*i+2] - input[4*i+3];
263        const int z3= input[4*i+2] + input[4*i+3];
264
265        temp[4*i+0]= z0+z3;
266        temp[4*i+1]= z0-z3;
267        temp[4*i+2]= z1-z2;
268        temp[4*i+3]= z1+z2;
269    }
270
271    for(i=0; i<4; i++){
272        const int offset= x_offset[i];
273        const SUINT z0= temp[4*0+i] + temp[4*2+i];
274        const SUINT z1= temp[4*0+i] - temp[4*2+i];
275        const SUINT z2= temp[4*1+i] - temp[4*3+i];
276        const SUINT z3= temp[4*1+i] + temp[4*3+i];
277
278        output[stride* 0+offset]= (int)((z0 + z3)*qmul + 128 ) >> 8;
279        output[stride* 1+offset]= (int)((z1 + z2)*qmul + 128 ) >> 8;
280        output[stride* 4+offset]= (int)((z1 - z2)*qmul + 128 ) >> 8;
281        output[stride* 5+offset]= (int)((z0 - z3)*qmul + 128 ) >> 8;
282    }
283#undef stride
284}
285
286void FUNCC(ff_h264_chroma422_dc_dequant_idct)(int16_t *_block, int qmul){
287    const int stride= 16*2;
288    const int xStride= 16;
289    int i;
290    unsigned temp[8];
291    static const uint8_t x_offset[2]={0, 16};
292    dctcoef *block = (dctcoef*)_block;
293
294    for(i=0; i<4; i++){
295        temp[2*i+0] = block[stride*i + xStride*0] + (unsigned)block[stride*i + xStride*1];
296        temp[2*i+1] = block[stride*i + xStride*0] - (unsigned)block[stride*i + xStride*1];
297    }
298
299    for(i=0; i<2; i++){
300        const int offset= x_offset[i];
301        const SUINT z0= temp[2*0+i] + temp[2*2+i];
302        const SUINT z1= temp[2*0+i] - temp[2*2+i];
303        const SUINT z2= temp[2*1+i] - temp[2*3+i];
304        const SUINT z3= temp[2*1+i] + temp[2*3+i];
305
306        block[stride*0+offset]= (int)((z0 + z3)*qmul + 128) >> 8;
307        block[stride*1+offset]= (int)((z1 + z2)*qmul + 128) >> 8;
308        block[stride*2+offset]= (int)((z1 - z2)*qmul + 128) >> 8;
309        block[stride*3+offset]= (int)((z0 - z3)*qmul + 128) >> 8;
310    }
311}
312
313void FUNCC(ff_h264_chroma_dc_dequant_idct)(int16_t *_block, int qmul){
314    const int stride= 16*2;
315    const int xStride= 16;
316    SUINT a,b,c,d,e;
317    dctcoef *block = (dctcoef*)_block;
318
319    a= block[stride*0 + xStride*0];
320    b= block[stride*0 + xStride*1];
321    c= block[stride*1 + xStride*0];
322    d= block[stride*1 + xStride*1];
323
324    e= a-b;
325    a= a+b;
326    b= c-d;
327    c= c+d;
328
329    block[stride*0 + xStride*0]= (int)((a+c)*qmul) >> 7;
330    block[stride*0 + xStride*1]= (int)((e+b)*qmul) >> 7;
331    block[stride*1 + xStride*0]= (int)((a-c)*qmul) >> 7;
332    block[stride*1 + xStride*1]= (int)((e-b)*qmul) >> 7;
333}
334