f71b9a8344ecbcee571acae472d59a45a927ac15
[libav.git] / libavcodec / vp56.h
1 /*
2 * Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org>
3 *
4 * This file is part of Libav.
5 *
6 * Libav 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 * Libav 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 Libav; 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 "dsputil.h"
30 #include "get_bits.h"
31 #include "hpeldsp.h"
32 #include "bytestream.h"
33 #include "h264chroma.h"
34 #include "videodsp.h"
35 #include "vp3dsp.h"
36 #include "vp56dsp.h"
37
38 typedef struct vp56_context VP56Context;
39
40 typedef enum {
41 VP56_FRAME_NONE =-1,
42 VP56_FRAME_CURRENT = 0,
43 VP56_FRAME_PREVIOUS = 1,
44 VP56_FRAME_GOLDEN = 2,
45 VP56_FRAME_GOLDEN2 = 3,
46 } VP56Frame;
47
48 typedef enum {
49 VP56_MB_INTER_NOVEC_PF = 0, /**< Inter MB, no vector, from previous frame */
50 VP56_MB_INTRA = 1, /**< Intra MB */
51 VP56_MB_INTER_DELTA_PF = 2, /**< Inter MB, above/left vector + delta, from previous frame */
52 VP56_MB_INTER_V1_PF = 3, /**< Inter MB, first vector, from previous frame */
53 VP56_MB_INTER_V2_PF = 4, /**< Inter MB, second vector, from previous frame */
54 VP56_MB_INTER_NOVEC_GF = 5, /**< Inter MB, no vector, from golden frame */
55 VP56_MB_INTER_DELTA_GF = 6, /**< Inter MB, above/left vector + delta, from golden frame */
56 VP56_MB_INTER_4V = 7, /**< Inter MB, 4 vectors, from previous frame */
57 VP56_MB_INTER_V1_GF = 8, /**< Inter MB, first vector, from golden frame */
58 VP56_MB_INTER_V2_GF = 9, /**< Inter MB, second vector, from golden frame */
59 } VP56mb;
60
61 typedef struct VP56Tree {
62 int8_t val;
63 int8_t prob_idx;
64 } VP56Tree;
65
66 typedef struct VP56mv {
67 DECLARE_ALIGNED(4, int16_t, x);
68 int16_t y;
69 } VP56mv;
70
71 #define VP56_SIZE_CHANGE 1
72
73 typedef void (*VP56ParseVectorAdjustment)(VP56Context *s,
74 VP56mv *vect);
75 typedef void (*VP56Filter)(VP56Context *s, uint8_t *dst, uint8_t *src,
76 int offset1, int offset2, int stride,
77 VP56mv mv, int mask, int select, int luma);
78 typedef void (*VP56ParseCoeff)(VP56Context *s);
79 typedef void (*VP56DefaultModelsInit)(VP56Context *s);
80 typedef void (*VP56ParseVectorModels)(VP56Context *s);
81 typedef int (*VP56ParseCoeffModels)(VP56Context *s);
82 typedef int (*VP56ParseHeader)(VP56Context *s, const uint8_t *buf,
83 int buf_size, int *golden_frame);
84
85 typedef struct VP56RangeCoder {
86 int high;
87 int bits; /* stored negated (i.e. negative "bits" is a positive number of
88 bits left) in order to eliminate a negate in cache refilling */
89 const uint8_t *buffer;
90 const uint8_t *end;
91 unsigned int code_word;
92 } VP56RangeCoder;
93
94 typedef struct VP56RefDc {
95 uint8_t not_null_dc;
96 VP56Frame ref_frame;
97 int16_t dc_coeff;
98 } VP56RefDc;
99
100 typedef struct VP56Macroblock {
101 uint8_t type;
102 VP56mv mv;
103 } VP56Macroblock;
104
105 typedef struct VP56Model {
106 uint8_t coeff_reorder[64]; /* used in vp6 only */
107 uint8_t coeff_index_to_pos[64]; /* used in vp6 only */
108 uint8_t vector_sig[2]; /* delta sign */
109 uint8_t vector_dct[2]; /* delta coding types */
110 uint8_t vector_pdi[2][2]; /* predefined delta init */
111 uint8_t vector_pdv[2][7]; /* predefined delta values */
112 uint8_t vector_fdv[2][8]; /* 8 bit delta value definition */
113 uint8_t coeff_dccv[2][11]; /* DC coeff value */
114 uint8_t coeff_ract[2][3][6][11]; /* Run/AC coding type and AC coeff value */
115 uint8_t coeff_acct[2][3][3][6][5];/* vp5 only AC coding type for coding group < 3 */
116 uint8_t coeff_dcct[2][36][5]; /* DC coeff coding type */
117 uint8_t coeff_runv[2][14]; /* run value (vp6 only) */
118 uint8_t mb_type[3][10][10]; /* model for decoding MB type */
119 uint8_t mb_types_stats[3][10][2];/* contextual, next MB type stats */
120 } VP56Model;
121
122 struct vp56_context {
123 AVCodecContext *avctx;
124 H264ChromaContext h264chroma;
125 HpelDSPContext hdsp;
126 VideoDSPContext vdsp;
127 VP3DSPContext vp3dsp;
128 VP56DSPContext vp56dsp;
129 uint8_t idct_scantable[64];
130 AVFrame *frames[4];
131 uint8_t *edge_emu_buffer_alloc;
132 uint8_t *edge_emu_buffer;
133 VP56RangeCoder c;
134 VP56RangeCoder cc;
135 VP56RangeCoder *ccp;
136 int sub_version;
137
138 /* frame info */
139 int plane_width[4];
140 int plane_height[4];
141 int mb_width; /* number of horizontal MB */
142 int mb_height; /* number of vertical MB */
143 int block_offset[6];
144
145 int quantizer;
146 uint16_t dequant_dc;
147 uint16_t dequant_ac;
148
149 /* DC predictors management */
150 VP56RefDc *above_blocks;
151 VP56RefDc left_block[4];
152 int above_block_idx[6];
153 int16_t prev_dc[3][3]; /* [plan][ref_frame] */
154
155 /* blocks / macroblock */
156 VP56mb mb_type;
157 VP56Macroblock *macroblocks;
158 DECLARE_ALIGNED(16, int16_t, block_coeff)[6][64];
159
160 /* motion vectors */
161 VP56mv mv[6]; /* vectors for each block in MB */
162 VP56mv vector_candidate[2];
163 int vector_candidate_pos;
164
165 /* filtering hints */
166 int filter_header; /* used in vp6 only */
167 int deblock_filtering;
168 int filter_selection;
169 int filter_mode;
170 int max_vector_length;
171 int sample_variance_threshold;
172
173 uint8_t coeff_ctx[4][64]; /* used in vp5 only */
174 uint8_t coeff_ctx_last[4]; /* used in vp5 only */
175
176 int has_alpha;
177
178 /* upside-down flipping hints */
179 int flip; /* are we flipping ? */
180 int frbi; /* first row block index in MB */
181 int srbi; /* second row block index in MB */
182 int stride[4]; /* stride for each plan */
183
184 const uint8_t *vp56_coord_div;
185 VP56ParseVectorAdjustment parse_vector_adjustment;
186 VP56Filter filter;
187 VP56ParseCoeff parse_coeff;
188 VP56DefaultModelsInit default_models_init;
189 VP56ParseVectorModels parse_vector_models;
190 VP56ParseCoeffModels parse_coeff_models;
191 VP56ParseHeader parse_header;
192
193 VP56Model *modelp;
194 VP56Model models[2];
195
196 /* huffman decoding */
197 int use_huffman;
198 GetBitContext gb;
199 VLC dccv_vlc[2];
200 VLC runv_vlc[2];
201 VLC ract_vlc[2][3][6];
202 unsigned int nb_null[2][2]; /* number of consecutive NULL DC/AC */
203 };
204
205
206 int ff_vp56_init(AVCodecContext *avctx, int flip, int has_alpha);
207 int ff_vp56_free(AVCodecContext *avctx);
208 void ff_vp56_init_dequant(VP56Context *s, int quantizer);
209 int ff_vp56_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
210 AVPacket *avpkt);
211
212
213 /**
214 * vp56 specific range coder implementation
215 */
216
217 extern const uint8_t ff_vp56_norm_shift[256];
218 void ff_vp56_init_range_decoder(VP56RangeCoder *c, const uint8_t *buf, int buf_size);
219
220 static av_always_inline unsigned int vp56_rac_renorm(VP56RangeCoder *c)
221 {
222 int shift = ff_vp56_norm_shift[c->high];
223 int bits = c->bits;
224 unsigned int code_word = c->code_word;
225
226 c->high <<= shift;
227 code_word <<= shift;
228 bits += shift;
229 if(bits >= 0 && c->buffer < c->end) {
230 code_word |= bytestream_get_be16(&c->buffer) << bits;
231 bits -= 16;
232 }
233 c->bits = bits;
234 return code_word;
235 }
236
237 #if ARCH_ARM
238 #include "arm/vp56_arith.h"
239 #elif ARCH_X86
240 #include "x86/vp56_arith.h"
241 #endif
242
243 #ifndef vp56_rac_get_prob
244 #define vp56_rac_get_prob vp56_rac_get_prob
245 static av_always_inline int vp56_rac_get_prob(VP56RangeCoder *c, uint8_t prob)
246 {
247 unsigned int code_word = vp56_rac_renorm(c);
248 unsigned int low = 1 + (((c->high - 1) * prob) >> 8);
249 unsigned int low_shift = low << 16;
250 int bit = code_word >= low_shift;
251
252 c->high = bit ? c->high - low : low;
253 c->code_word = bit ? code_word - low_shift : code_word;
254
255 return bit;
256 }
257 #endif
258
259 #ifndef vp56_rac_get_prob_branchy
260 // branchy variant, to be used where there's a branch based on the bit decoded
261 static av_always_inline int vp56_rac_get_prob_branchy(VP56RangeCoder *c, int prob)
262 {
263 unsigned long code_word = vp56_rac_renorm(c);
264 unsigned low = 1 + (((c->high - 1) * prob) >> 8);
265 unsigned low_shift = low << 16;
266
267 if (code_word >= low_shift) {
268 c->high -= low;
269 c->code_word = code_word - low_shift;
270 return 1;
271 }
272
273 c->high = low;
274 c->code_word = code_word;
275 return 0;
276 }
277 #endif
278
279 static av_always_inline int vp56_rac_get(VP56RangeCoder *c)
280 {
281 unsigned int code_word = vp56_rac_renorm(c);
282 /* equiprobable */
283 int low = (c->high + 1) >> 1;
284 unsigned int low_shift = low << 16;
285 int bit = code_word >= low_shift;
286 if (bit) {
287 c->high -= low;
288 code_word -= low_shift;
289 } else {
290 c->high = low;
291 }
292
293 c->code_word = code_word;
294 return bit;
295 }
296
297 // rounding is different than vp56_rac_get, is vp56_rac_get wrong?
298 static av_always_inline int vp8_rac_get(VP56RangeCoder *c)
299 {
300 return vp56_rac_get_prob(c, 128);
301 }
302
303 static av_unused int vp56_rac_gets(VP56RangeCoder *c, int bits)
304 {
305 int value = 0;
306
307 while (bits--) {
308 value = (value << 1) | vp56_rac_get(c);
309 }
310
311 return value;
312 }
313
314 static av_unused int vp8_rac_get_uint(VP56RangeCoder *c, int bits)
315 {
316 int value = 0;
317
318 while (bits--) {
319 value = (value << 1) | vp8_rac_get(c);
320 }
321
322 return value;
323 }
324
325 // fixme: add 1 bit to all the calls to this?
326 static av_unused int vp8_rac_get_sint(VP56RangeCoder *c, int bits)
327 {
328 int v;
329
330 if (!vp8_rac_get(c))
331 return 0;
332
333 v = vp8_rac_get_uint(c, bits);
334
335 if (vp8_rac_get(c))
336 v = -v;
337
338 return v;
339 }
340
341 // P(7)
342 static av_unused int vp56_rac_gets_nn(VP56RangeCoder *c, int bits)
343 {
344 int v = vp56_rac_gets(c, 7) << 1;
345 return v + !v;
346 }
347
348 static av_unused int vp8_rac_get_nn(VP56RangeCoder *c)
349 {
350 int v = vp8_rac_get_uint(c, 7) << 1;
351 return v + !v;
352 }
353
354 static av_always_inline
355 int vp56_rac_get_tree(VP56RangeCoder *c,
356 const VP56Tree *tree,
357 const uint8_t *probs)
358 {
359 while (tree->val > 0) {
360 if (vp56_rac_get_prob(c, probs[tree->prob_idx]))
361 tree += tree->val;
362 else
363 tree++;
364 }
365 return -tree->val;
366 }
367
368 /**
369 * This is identical to vp8_rac_get_tree except for the possibility of starting
370 * on a node other than the root node, needed for coeff decode where this is
371 * used to save a bit after a 0 token (by disallowing EOB to immediately follow.)
372 */
373 static av_always_inline
374 int vp8_rac_get_tree_with_offset(VP56RangeCoder *c, const int8_t (*tree)[2],
375 const uint8_t *probs, int i)
376 {
377 do {
378 i = tree[i][vp56_rac_get_prob(c, probs[i])];
379 } while (i > 0);
380
381 return -i;
382 }
383
384 // how probabilities are associated with decisions is different I think
385 // well, the new scheme fits in the old but this way has one fewer branches per decision
386 static av_always_inline
387 int vp8_rac_get_tree(VP56RangeCoder *c, const int8_t (*tree)[2],
388 const uint8_t *probs)
389 {
390 return vp8_rac_get_tree_with_offset(c, tree, probs, 0);
391 }
392
393 // DCTextra
394 static av_always_inline int vp8_rac_get_coeff(VP56RangeCoder *c, const uint8_t *prob)
395 {
396 int v = 0;
397
398 do {
399 v = (v<<1) + vp56_rac_get_prob(c, *prob++);
400 } while (*prob);
401
402 return v;
403 }
404
405 #endif /* AVCODEC_VP56_H */