1 /*
2 * Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org>
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 /**
22 * @file
23 * VP5 and VP6 compatible video decoder (common features)
24 */
25
26 #ifndef AVCODEC_VP56_H
27 #define AVCODEC_VP56_H
28
29 #include "libavutil/mem_internal.h"
30
31 #include "avcodec.h"
32 #include "get_bits.h"
33 #include "hpeldsp.h"
34 #include "bytestream.h"
35 #include "h264chroma.h"
36 #include "videodsp.h"
37 #include "vp3dsp.h"
38 #include "vp56dsp.h"
39
40 typedef struct vp56_context VP56Context;
41
42 typedef enum {
43 VP56_FRAME_NONE =-1,
44 VP56_FRAME_CURRENT = 0,
45 VP56_FRAME_PREVIOUS = 1,
46 VP56_FRAME_GOLDEN = 2,
47 VP56_FRAME_GOLDEN2 = 3,
48 } VP56Frame;
49
50 typedef enum {
51 VP56_MB_INTER_NOVEC_PF = 0, /**< Inter MB, no vector, from previous frame */
52 VP56_MB_INTRA = 1, /**< Intra MB */
53 VP56_MB_INTER_DELTA_PF = 2, /**< Inter MB, above/left vector + delta, from previous frame */
54 VP56_MB_INTER_V1_PF = 3, /**< Inter MB, first vector, from previous frame */
55 VP56_MB_INTER_V2_PF = 4, /**< Inter MB, second vector, from previous frame */
56 VP56_MB_INTER_NOVEC_GF = 5, /**< Inter MB, no vector, from golden frame */
57 VP56_MB_INTER_DELTA_GF = 6, /**< Inter MB, above/left vector + delta, from golden frame */
58 VP56_MB_INTER_4V = 7, /**< Inter MB, 4 vectors, from previous frame */
59 VP56_MB_INTER_V1_GF = 8, /**< Inter MB, first vector, from golden frame */
60 VP56_MB_INTER_V2_GF = 9, /**< Inter MB, second vector, from golden frame */
61 } VP56mb;
62
63 typedef struct VP56Tree {
64 int8_t val;
65 int8_t prob_idx;
66 } VP56Tree;
67
68 typedef struct VP56mv {
69 DECLARE_ALIGNED(4, int16_t, x);
70 int16_t y;
71 } VP56mv;
72
73 #define VP56_SIZE_CHANGE 1
74
75 typedef void (*VP56ParseVectorAdjustment)(VP56Context *s,
76 VP56mv *vect);
77 typedef void (*VP56Filter)(VP56Context *s, uint8_t *dst, uint8_t *src,
78 int offset1, int offset2, ptrdiff_t stride,
79 VP56mv mv, int mask, int select, int luma);
80 typedef int (*VP56ParseCoeff)(VP56Context *s);
81 typedef void (*VP56DefaultModelsInit)(VP56Context *s);
82 typedef void (*VP56ParseVectorModels)(VP56Context *s);
83 typedef int (*VP56ParseCoeffModels)(VP56Context *s);
84 typedef int (*VP56ParseHeader)(VP56Context *s, const uint8_t *buf,
85 int buf_size);
86
87 typedef struct VP56RangeCoder {
88 int high;
89 int bits; /* stored negated (i.e. negative "bits" is a positive number of
90 bits left) in order to eliminate a negate in cache refilling */
91 const uint8_t *buffer;
92 const uint8_t *end;
93 unsigned int code_word;
94 int end_reached;
95 } VP56RangeCoder;
96
97 typedef struct VP56RefDc {
98 uint8_t not_null_dc;
99 VP56Frame ref_frame;
100 int16_t dc_coeff;
101 } VP56RefDc;
102
103 typedef struct VP56Macroblock {
104 uint8_t type;
105 VP56mv mv;
106 } VP56Macroblock;
107
108 typedef struct VP56Model {
109 uint8_t coeff_reorder[64]; /* used in vp6 only */
110 uint8_t coeff_index_to_pos[64]; /* used in vp6 only */
111 uint8_t coeff_index_to_idct_selector[64]; /* used in vp6 only */
112 uint8_t vector_sig[2]; /* delta sign */
113 uint8_t vector_dct[2]; /* delta coding types */
114 uint8_t vector_pdi[2][2]; /* predefined delta init */
115 uint8_t vector_pdv[2][7]; /* predefined delta values */
116 uint8_t vector_fdv[2][8]; /* 8 bit delta value definition */
117 uint8_t coeff_dccv[2][11]; /* DC coeff value */
118 uint8_t coeff_ract[2][3][6][11]; /* Run/AC coding type and AC coeff value */
119 uint8_t coeff_acct[2][3][3][6][5];/* vp5 only AC coding type for coding group < 3 */
120 uint8_t coeff_dcct[2][36][5]; /* DC coeff coding type */
121 uint8_t coeff_runv[2][14]; /* run value (vp6 only) */
122 uint8_t mb_type[3][10][10]; /* model for decoding MB type */
123 uint8_t mb_types_stats[3][10][2];/* contextual, next MB type stats */
124 } VP56Model;
125
126 struct vp56_context {
127 AVCodecContext *avctx;
128 H264ChromaContext h264chroma;
129 HpelDSPContext hdsp;
130 VideoDSPContext vdsp;
131 VP3DSPContext vp3dsp;
132 VP56DSPContext vp56dsp;
133 uint8_t idct_scantable[64];
134 AVFrame *frames[4];
135 uint8_t *edge_emu_buffer_alloc;
136 uint8_t *edge_emu_buffer;
137 VP56RangeCoder c;
138 VP56RangeCoder cc;
139 VP56RangeCoder *ccp;
140 int sub_version;
141
142 /* frame info */
143 int golden_frame;
144 int plane_width[4];
145 int plane_height[4];
146 int mb_width; /* number of horizontal MB */
147 int mb_height; /* number of vertical MB */
148 int block_offset[6];
149
150 int quantizer;
151 uint16_t dequant_dc;
152 uint16_t dequant_ac;
153
154 /* DC predictors management */
155 VP56RefDc *above_blocks;
156 VP56RefDc left_block[4];
157 int above_block_idx[6];
158 int16_t prev_dc[3][3]; /* [plan][ref_frame] */
159
160 /* blocks / macroblock */
161 VP56mb mb_type;
162 VP56Macroblock *macroblocks;
163 DECLARE_ALIGNED(16, int16_t, block_coeff)[6][64];
164 int idct_selector[6];
165
166 /* motion vectors */
167 VP56mv mv[6]; /* vectors for each block in MB */
168 VP56mv vector_candidate[2];
169 int vector_candidate_pos;
170
171 /* filtering hints */
172 int filter_header; /* used in vp6 only */
173 int deblock_filtering;
174 int filter_selection;
175 int filter_mode;
176 int max_vector_length;
177 int sample_variance_threshold;
178 DECLARE_ALIGNED(8, int, bounding_values_array)[256];
179
180 uint8_t coeff_ctx[4][64]; /* used in vp5 only */
181 uint8_t coeff_ctx_last[4]; /* used in vp5 only */
182
183 int has_alpha;
184
185 /* upside-down flipping hints */
186 int flip; /* are we flipping ? */
187 int frbi; /* first row block index in MB */
188 int srbi; /* second row block index in MB */
189 ptrdiff_t stride[4]; /* stride for each plan */
190
191 const uint8_t *vp56_coord_div;
192 VP56ParseVectorAdjustment parse_vector_adjustment;
193 VP56Filter filter;
194 VP56ParseCoeff parse_coeff;
195 VP56DefaultModelsInit default_models_init;
196 VP56ParseVectorModels parse_vector_models;
197 VP56ParseCoeffModels parse_coeff_models;
198 VP56ParseHeader parse_header;
199
200 /* for "slice" parallelism between YUV and A */
201 VP56Context *alpha_context;
202
203 VP56Model *modelp;
204 VP56Model model;
205
206 /* huffman decoding */
207 int use_huffman;
208 GetBitContext gb;
209 VLC dccv_vlc[2];
210 VLC runv_vlc[2];
211 VLC ract_vlc[2][3][6];
212 unsigned int nb_null[2][2]; /* number of consecutive NULL DC/AC */
213
214 int have_undamaged_frame;
215 int discard_frame;
216 };
217
218
219 /**
220 * Initializes an VP56Context. Expects its caller to clean up
221 * in case of error.
222 */
223 int ff_vp56_init_context(AVCodecContext *avctx, VP56Context *s,
224 int flip, int has_alpha);
225 int ff_vp56_free_context(VP56Context *s);
226 void ff_vp56_init_dequant(VP56Context *s, int quantizer);
227 int ff_vp56_decode_frame(AVCodecContext *avctx, AVFrame *frame,
228 int *got_frame, AVPacket *avpkt);
229
230
231 /**
232 * vp56 specific range coder implementation
233 */
234
235 extern const uint8_t ff_vp56_norm_shift[256];
236 int ff_vp56_init_range_decoder(VP56RangeCoder *c, const uint8_t *buf, int buf_size);
237
238 /**
239 * vp5689 returns 1 if the end of the stream has been reached, 0 otherwise.
240 */
vpX_rac_is_end(VP56RangeCoder *c)241 static av_always_inline int vpX_rac_is_end(VP56RangeCoder *c)
242 {
243 if (c->end <= c->buffer && c->bits >= 0)
244 c->end_reached ++;
245 return c->end_reached > 10;
246 }
247
vp56_rac_renorm(VP56RangeCoder *c)248 static av_always_inline unsigned int vp56_rac_renorm(VP56RangeCoder *c)
249 {
250 int shift = ff_vp56_norm_shift[c->high];
251 int bits = c->bits;
252 unsigned int code_word = c->code_word;
253
254 c->high <<= shift;
255 code_word <<= shift;
256 bits += shift;
257 if(bits >= 0 && c->buffer < c->end) {
258 code_word |= bytestream_get_be16(&c->buffer) << bits;
259 bits -= 16;
260 }
261 c->bits = bits;
262 return code_word;
263 }
264
265 #if ARCH_ARM
266 #include "arm/vp56_arith.h"
267 #elif ARCH_X86
268 #include "x86/vp56_arith.h"
269 #endif
270
271 #ifndef vp56_rac_get_prob
272 #define vp56_rac_get_prob vp56_rac_get_prob
vp56_rac_get_prob(VP56RangeCoder *c, uint8_t prob)273 static av_always_inline int vp56_rac_get_prob(VP56RangeCoder *c, uint8_t prob)
274 {
275 unsigned int code_word = vp56_rac_renorm(c);
276 unsigned int low = 1 + (((c->high - 1) * prob) >> 8);
277 unsigned int low_shift = low << 16;
278 int bit = code_word >= low_shift;
279
280 c->high = bit ? c->high - low : low;
281 c->code_word = bit ? code_word - low_shift : code_word;
282
283 return bit;
284 }
285 #endif
286
287 #ifndef vp56_rac_get_prob_branchy
288 // branchy variant, to be used where there's a branch based on the bit decoded
vp56_rac_get_prob_branchy(VP56RangeCoder *c, int prob)289 static av_always_inline int vp56_rac_get_prob_branchy(VP56RangeCoder *c, int prob)
290 {
291 unsigned long code_word = vp56_rac_renorm(c);
292 unsigned low = 1 + (((c->high - 1) * prob) >> 8);
293 unsigned low_shift = low << 16;
294
295 if (code_word >= low_shift) {
296 c->high -= low;
297 c->code_word = code_word - low_shift;
298 return 1;
299 }
300
301 c->high = low;
302 c->code_word = code_word;
303 return 0;
304 }
305 #endif
306
vp56_rac_get(VP56RangeCoder *c)307 static av_always_inline int vp56_rac_get(VP56RangeCoder *c)
308 {
309 unsigned int code_word = vp56_rac_renorm(c);
310 /* equiprobable */
311 int low = (c->high + 1) >> 1;
312 unsigned int low_shift = low << 16;
313 int bit = code_word >= low_shift;
314 if (bit) {
315 c->high -= low;
316 code_word -= low_shift;
317 } else {
318 c->high = low;
319 }
320
321 c->code_word = code_word;
322 return bit;
323 }
324
325 // rounding is different than vp56_rac_get, is vp56_rac_get wrong?
vp8_rac_get(VP56RangeCoder *c)326 static av_always_inline int vp8_rac_get(VP56RangeCoder *c)
327 {
328 return vp56_rac_get_prob(c, 128);
329 }
330
vp56_rac_gets(VP56RangeCoder *c, int bits)331 static int vp56_rac_gets(VP56RangeCoder *c, int bits)
332 {
333 int value = 0;
334
335 while (bits--) {
336 value = (value << 1) | vp56_rac_get(c);
337 }
338
339 return value;
340 }
341
vp8_rac_get_uint(VP56RangeCoder *c, int bits)342 static int vp8_rac_get_uint(VP56RangeCoder *c, int bits)
343 {
344 int value = 0;
345
346 while (bits--) {
347 value = (value << 1) | vp8_rac_get(c);
348 }
349
350 return value;
351 }
352
353 // fixme: add 1 bit to all the calls to this?
vp8_rac_get_sint(VP56RangeCoder *c, int bits)354 static av_unused int vp8_rac_get_sint(VP56RangeCoder *c, int bits)
355 {
356 int v;
357
358 if (!vp8_rac_get(c))
359 return 0;
360
361 v = vp8_rac_get_uint(c, bits);
362
363 if (vp8_rac_get(c))
364 v = -v;
365
366 return v;
367 }
368
369 // P(7)
vp56_rac_gets_nn(VP56RangeCoder *c, int bits)370 static av_unused int vp56_rac_gets_nn(VP56RangeCoder *c, int bits)
371 {
372 int v = vp56_rac_gets(c, 7) << 1;
373 return v + !v;
374 }
375
vp8_rac_get_nn(VP56RangeCoder *c)376 static av_unused int vp8_rac_get_nn(VP56RangeCoder *c)
377 {
378 int v = vp8_rac_get_uint(c, 7) << 1;
379 return v + !v;
380 }
381
382 static av_always_inline
vp56_rac_get_tree(VP56RangeCoder *c, const VP56Tree *tree, const uint8_t *probs)383 int vp56_rac_get_tree(VP56RangeCoder *c,
384 const VP56Tree *tree,
385 const uint8_t *probs)
386 {
387 while (tree->val > 0) {
388 if (vp56_rac_get_prob_branchy(c, probs[tree->prob_idx]))
389 tree += tree->val;
390 else
391 tree++;
392 }
393 return -tree->val;
394 }
395
396 // how probabilities are associated with decisions is different I think
397 // well, the new scheme fits in the old but this way has one fewer branches per decision
vp8_rac_get_tree(VP56RangeCoder *c, const int8_t (*tree)[2], const uint8_t *probs)398 static av_always_inline int vp8_rac_get_tree(VP56RangeCoder *c, const int8_t (*tree)[2],
399 const uint8_t *probs)
400 {
401 int i = 0;
402
403 do {
404 i = tree[i][vp56_rac_get_prob(c, probs[i])];
405 } while (i > 0);
406
407 return -i;
408 }
409
410 // DCTextra
vp8_rac_get_coeff(VP56RangeCoder *c, const uint8_t *prob)411 static av_always_inline int vp8_rac_get_coeff(VP56RangeCoder *c, const uint8_t *prob)
412 {
413 int v = 0;
414
415 do {
416 v = (v<<1) + vp56_rac_get_prob(c, *prob++);
417 } while (*prob);
418
419 return v;
420 }
421
422 #endif /* AVCODEC_VP56_H */
423