efc403e11052cb2641310a2d05da18707ac9bd69
[libav.git] / libavcodec / vp56.h
1 /**
2 * @file
3 * VP5 and VP6 compatible video decoder (common features)
4 *
5 * Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org>
6 *
7 * This file is part of FFmpeg.
8 *
9 * FFmpeg is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
13 *
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with FFmpeg; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 */
23
24 #ifndef AVCODEC_VP56_H
25 #define AVCODEC_VP56_H
26
27 #include "vp56data.h"
28 #include "dsputil.h"
29 #include "get_bits.h"
30 #include "bytestream.h"
31 #include "cabac.h"
32 #include "vp56dsp.h"
33
34 typedef struct vp56_context VP56Context;
35
36 typedef struct {
37 int16_t x;
38 int16_t y;
39 } DECLARE_ALIGNED(4, , VP56mv);
40
41 typedef void (*VP56ParseVectorAdjustment)(VP56Context *s,
42 VP56mv *vect);
43 typedef void (*VP56Filter)(VP56Context *s, uint8_t *dst, uint8_t *src,
44 int offset1, int offset2, int stride,
45 VP56mv mv, int mask, int select, int luma);
46 typedef void (*VP56ParseCoeff)(VP56Context *s);
47 typedef void (*VP56DefaultModelsInit)(VP56Context *s);
48 typedef void (*VP56ParseVectorModels)(VP56Context *s);
49 typedef void (*VP56ParseCoeffModels)(VP56Context *s);
50 typedef int (*VP56ParseHeader)(VP56Context *s, const uint8_t *buf,
51 int buf_size, int *golden_frame);
52
53 typedef struct {
54 int high;
55 int bits; /* stored negated (i.e. negative "bits" is a positive number of
56 bits left) in order to eliminate a negate in cache refilling */
57 const uint8_t *buffer;
58 const uint8_t *end;
59 unsigned int code_word;
60 } VP56RangeCoder;
61
62 typedef struct {
63 uint8_t not_null_dc;
64 VP56Frame ref_frame;
65 DCTELEM dc_coeff;
66 } VP56RefDc;
67
68 typedef struct {
69 uint8_t type;
70 VP56mv mv;
71 } VP56Macroblock;
72
73 typedef struct {
74 uint8_t coeff_reorder[64]; /* used in vp6 only */
75 uint8_t coeff_index_to_pos[64]; /* used in vp6 only */
76 uint8_t vector_sig[2]; /* delta sign */
77 uint8_t vector_dct[2]; /* delta coding types */
78 uint8_t vector_pdi[2][2]; /* predefined delta init */
79 uint8_t vector_pdv[2][7]; /* predefined delta values */
80 uint8_t vector_fdv[2][8]; /* 8 bit delta value definition */
81 uint8_t coeff_dccv[2][11]; /* DC coeff value */
82 uint8_t coeff_ract[2][3][6][11]; /* Run/AC coding type and AC coeff value */
83 uint8_t coeff_acct[2][3][3][6][5];/* vp5 only AC coding type for coding group < 3 */
84 uint8_t coeff_dcct[2][36][5]; /* DC coeff coding type */
85 uint8_t coeff_runv[2][14]; /* run value (vp6 only) */
86 uint8_t mb_type[3][10][10]; /* model for decoding MB type */
87 uint8_t mb_types_stats[3][10][2];/* contextual, next MB type stats */
88 } VP56Model;
89
90 struct vp56_context {
91 AVCodecContext *avctx;
92 DSPContext dsp;
93 VP56DSPContext vp56dsp;
94 ScanTable scantable;
95 AVFrame frames[4];
96 AVFrame *framep[6];
97 uint8_t *edge_emu_buffer_alloc;
98 uint8_t *edge_emu_buffer;
99 VP56RangeCoder c;
100 VP56RangeCoder cc;
101 VP56RangeCoder *ccp;
102 int sub_version;
103
104 /* frame info */
105 int plane_width[4];
106 int plane_height[4];
107 int mb_width; /* number of horizontal MB */
108 int mb_height; /* number of vertical MB */
109 int block_offset[6];
110
111 int quantizer;
112 uint16_t dequant_dc;
113 uint16_t dequant_ac;
114 int8_t *qscale_table;
115
116 /* DC predictors management */
117 VP56RefDc *above_blocks;
118 VP56RefDc left_block[4];
119 int above_block_idx[6];
120 DCTELEM prev_dc[3][3]; /* [plan][ref_frame] */
121
122 /* blocks / macroblock */
123 VP56mb mb_type;
124 VP56Macroblock *macroblocks;
125 DECLARE_ALIGNED(16, DCTELEM, block_coeff)[6][64];
126
127 /* motion vectors */
128 VP56mv mv[6]; /* vectors for each block in MB */
129 VP56mv vector_candidate[2];
130 int vector_candidate_pos;
131
132 /* filtering hints */
133 int filter_header; /* used in vp6 only */
134 int deblock_filtering;
135 int filter_selection;
136 int filter_mode;
137 int max_vector_length;
138 int sample_variance_threshold;
139
140 uint8_t coeff_ctx[4][64]; /* used in vp5 only */
141 uint8_t coeff_ctx_last[4]; /* used in vp5 only */
142
143 int has_alpha;
144
145 /* upside-down flipping hints */
146 int flip; /* are we flipping ? */
147 int frbi; /* first row block index in MB */
148 int srbi; /* second row block index in MB */
149 int stride[4]; /* stride for each plan */
150
151 const uint8_t *vp56_coord_div;
152 VP56ParseVectorAdjustment parse_vector_adjustment;
153 VP56Filter filter;
154 VP56ParseCoeff parse_coeff;
155 VP56DefaultModelsInit default_models_init;
156 VP56ParseVectorModels parse_vector_models;
157 VP56ParseCoeffModels parse_coeff_models;
158 VP56ParseHeader parse_header;
159
160 VP56Model *modelp;
161 VP56Model models[2];
162
163 /* huffman decoding */
164 int use_huffman;
165 GetBitContext gb;
166 VLC dccv_vlc[2];
167 VLC runv_vlc[2];
168 VLC ract_vlc[2][3][6];
169 unsigned int nb_null[2][2]; /* number of consecutive NULL DC/AC */
170 };
171
172
173 void ff_vp56_init(AVCodecContext *avctx, int flip, int has_alpha);
174 int ff_vp56_free(AVCodecContext *avctx);
175 void ff_vp56_init_dequant(VP56Context *s, int quantizer);
176 int ff_vp56_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
177 AVPacket *avpkt);
178
179
180 /**
181 * vp56 specific range coder implementation
182 */
183
184 static inline void vp56_init_range_decoder(VP56RangeCoder *c,
185 const uint8_t *buf, int buf_size)
186 {
187 c->high = 255;
188 c->bits = -8;
189 c->buffer = buf;
190 c->end = buf + buf_size;
191 c->code_word = bytestream_get_be16(&c->buffer);
192 }
193
194 static av_always_inline unsigned int vp56_rac_renorm(VP56RangeCoder *c)
195 {
196 int shift = ff_h264_norm_shift[c->high] - 1;
197 int bits = c->bits;
198 unsigned int code_word = c->code_word;
199
200 c->high <<= shift;
201 code_word <<= shift;
202 bits += shift;
203 if(bits >= 0 && c->buffer < c->end) {
204 code_word |= *c->buffer++ << bits;
205 bits -= 8;
206 }
207 c->bits = bits;
208 return code_word;
209 }
210
211 #if ARCH_X86
212 #include "x86/vp56_arith.h"
213 #endif
214
215 #ifndef vp56_rac_get_prob
216 #define vp56_rac_get_prob vp56_rac_get_prob
217 static inline int vp56_rac_get_prob(VP56RangeCoder *c, uint8_t prob)
218 {
219 unsigned int code_word = vp56_rac_renorm(c);
220 unsigned int low = 1 + (((c->high - 1) * prob) >> 8);
221 unsigned int low_shift = low << 8;
222 int bit = code_word >= low_shift;
223
224 c->high = bit ? c->high - low : low;
225 c->code_word = bit ? code_word - low_shift : code_word;
226
227 return bit;
228 }
229 #endif
230
231 // branchy variant, to be used where there's a branch based on the bit decoded
232 static av_always_inline int vp56_rac_get_prob_branchy(VP56RangeCoder *c, int prob)
233 {
234 unsigned long code_word = vp56_rac_renorm(c);
235 unsigned low = 1 + (((c->high - 1) * prob) >> 8);
236 unsigned low_shift = low << 8;
237
238 if (code_word >= low_shift) {
239 c->high -= low;
240 c->code_word = code_word - low_shift;
241 return 1;
242 }
243
244 c->high = low;
245 c->code_word = code_word;
246 return 0;
247 }
248
249 static inline int vp56_rac_get(VP56RangeCoder *c)
250 {
251 unsigned int code_word = vp56_rac_renorm(c);
252 /* equiprobable */
253 int low = (c->high + 1) >> 1;
254 unsigned int low_shift = low << 8;
255 int bit = code_word >= low_shift;
256 if (bit) {
257 c->high -= low;
258 code_word -= low_shift;
259 } else {
260 c->high = low;
261 }
262
263 c->code_word = code_word;
264 return bit;
265 }
266
267 // rounding is different than vp56_rac_get, is vp56_rac_get wrong?
268 static inline int vp8_rac_get(VP56RangeCoder *c)
269 {
270 return vp56_rac_get_prob(c, 128);
271 }
272
273 static inline int vp56_rac_gets(VP56RangeCoder *c, int bits)
274 {
275 int value = 0;
276
277 while (bits--) {
278 value = (value << 1) | vp56_rac_get(c);
279 }
280
281 return value;
282 }
283
284 static inline int vp8_rac_get_uint(VP56RangeCoder *c, int bits)
285 {
286 int value = 0;
287
288 while (bits--) {
289 value = (value << 1) | vp8_rac_get(c);
290 }
291
292 return value;
293 }
294
295 // fixme: add 1 bit to all the calls to this?
296 static inline int vp8_rac_get_sint(VP56RangeCoder *c, int bits)
297 {
298 int v;
299
300 if (!vp8_rac_get(c))
301 return 0;
302
303 v = vp8_rac_get_uint(c, bits);
304
305 if (vp8_rac_get(c))
306 v = -v;
307
308 return v;
309 }
310
311 // P(7)
312 static inline int vp56_rac_gets_nn(VP56RangeCoder *c, int bits)
313 {
314 int v = vp56_rac_gets(c, 7) << 1;
315 return v + !v;
316 }
317
318 static inline int vp8_rac_get_nn(VP56RangeCoder *c)
319 {
320 int v = vp8_rac_get_uint(c, 7) << 1;
321 return v + !v;
322 }
323
324 static inline int vp56_rac_get_tree(VP56RangeCoder *c,
325 const VP56Tree *tree,
326 const uint8_t *probs)
327 {
328 while (tree->val > 0) {
329 if (vp56_rac_get_prob(c, probs[tree->prob_idx]))
330 tree += tree->val;
331 else
332 tree++;
333 }
334 return -tree->val;
335 }
336
337 /**
338 * This is identical to vp8_rac_get_tree except for the possibility of starting
339 * on a node other than the root node, needed for coeff decode where this is
340 * used to save a bit after a 0 token (by disallowing EOB to immediately follow.)
341 */
342 static inline int vp8_rac_get_tree_with_offset(VP56RangeCoder *c, const int8_t (*tree)[2],
343 const uint8_t *probs, int i)
344 {
345 do {
346 i = tree[i][vp56_rac_get_prob(c, probs[i])];
347 } while (i > 0);
348
349 return -i;
350 }
351
352 // how probabilities are associated with decisions is different I think
353 // well, the new scheme fits in the old but this way has one fewer branches per decision
354 static inline int vp8_rac_get_tree(VP56RangeCoder *c, const int8_t (*tree)[2],
355 const uint8_t *probs)
356 {
357 return vp8_rac_get_tree_with_offset(c, tree, probs, 0);
358 }
359
360 // DCTextra
361 static inline int vp8_rac_get_coeff(VP56RangeCoder *c, const uint8_t *prob)
362 {
363 int v = 0;
364
365 do {
366 v = (v<<1) + vp56_rac_get_prob(c, *prob++);
367 } while (*prob);
368
369 return v;
370 }
371
372 #endif /* AVCODEC_VP56_H */