FFmpeg
vp56.h
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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 "avcodec.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 {
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, ptrdiff_t stride,
77  VP56mv mv, int mask, int select, int luma);
78 typedef int (*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);
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;
94 
95 typedef struct VP56RefDc {
98  int16_t dc_coeff;
99 } VP56RefDc;
100 
101 typedef struct VP56Macroblock {
105 
106 typedef struct VP56Model {
107  uint8_t coeff_reorder[64]; /* used in vp6 only */
108  uint8_t coeff_index_to_pos[64]; /* used in vp6 only */
109  uint8_t coeff_index_to_idct_selector[64]; /* used in vp6 only */
110  uint8_t vector_sig[2]; /* delta sign */
111  uint8_t vector_dct[2]; /* delta coding types */
112  uint8_t vector_pdi[2][2]; /* predefined delta init */
113  uint8_t vector_pdv[2][7]; /* predefined delta values */
114  uint8_t vector_fdv[2][8]; /* 8 bit delta value definition */
115  uint8_t coeff_dccv[2][11]; /* DC coeff value */
116  uint8_t coeff_ract[2][3][6][11]; /* Run/AC coding type and AC coeff value */
117  uint8_t coeff_acct[2][3][3][6][5];/* vp5 only AC coding type for coding group < 3 */
118  uint8_t coeff_dcct[2][36][5]; /* DC coeff coding type */
119  uint8_t coeff_runv[2][14]; /* run value (vp6 only) */
120  uint8_t mb_type[3][10][10]; /* model for decoding MB type */
121  uint8_t mb_types_stats[3][10][2];/* contextual, next MB type stats */
122 } VP56Model;
123 
124 struct vp56_context {
131  uint8_t idct_scantable[64];
139 
140  /* frame info */
142  int plane_width[4];
143  int plane_height[4];
144  int mb_width; /* number of horizontal MB */
145  int mb_height; /* number of vertical MB */
146  int block_offset[6];
147 
149  uint16_t dequant_dc;
150  uint16_t dequant_ac;
151 
152  /* DC predictors management */
154  VP56RefDc left_block[4];
155  int above_block_idx[6];
156  int16_t prev_dc[3][3]; /* [plan][ref_frame] */
157 
158  /* blocks / macroblock */
161  DECLARE_ALIGNED(16, int16_t, block_coeff)[6][64];
162  int idct_selector[6];
163 
164  /* motion vectors */
165  VP56mv mv[6]; /* vectors for each block in MB */
166  VP56mv vector_candidate[2];
168 
169  /* filtering hints */
170  int filter_header; /* used in vp6 only */
176  DECLARE_ALIGNED(8, int, bounding_values_array)[256];
177 
178  uint8_t coeff_ctx[4][64]; /* used in vp5 only */
179  uint8_t coeff_ctx_last[4]; /* used in vp5 only */
180 
182 
183  /* upside-down flipping hints */
184  int flip; /* are we flipping ? */
185  int frbi; /* first row block index in MB */
186  int srbi; /* second row block index in MB */
187  ptrdiff_t stride[4]; /* stride for each plan */
188 
197 
198  /* for "slice" parallelism between YUV and A */
199  VP56Context *alpha_context;
200 
203 
204  /* huffman decoding */
207  VLC dccv_vlc[2];
208  VLC runv_vlc[2];
209  VLC ract_vlc[2][3][6];
210  unsigned int nb_null[2][2]; /* number of consecutive NULL DC/AC */
211 
214 };
215 
216 
217 int ff_vp56_init(AVCodecContext *avctx, int flip, int has_alpha);
218 int ff_vp56_init_context(AVCodecContext *avctx, VP56Context *s,
219  int flip, int has_alpha);
220 int ff_vp56_free(AVCodecContext *avctx);
221 int ff_vp56_free_context(VP56Context *s);
222 void ff_vp56_init_dequant(VP56Context *s, int quantizer);
223 int ff_vp56_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
224  AVPacket *avpkt);
225 
226 
227 /**
228  * vp56 specific range coder implementation
229  */
230 
231 extern const uint8_t ff_vp56_norm_shift[256];
232 int ff_vp56_init_range_decoder(VP56RangeCoder *c, const uint8_t *buf, int buf_size);
233 
234 /**
235  * vp5689 returns 1 if the end of the stream has been reached, 0 otherwise.
236  */
238 {
239  if (c->end <= c->buffer && c->bits >= 0)
240  c->end_reached ++;
241  return c->end_reached > 10;
242 }
243 
245 {
246  int shift = ff_vp56_norm_shift[c->high];
247  int bits = c->bits;
248  unsigned int code_word = c->code_word;
249 
250  c->high <<= shift;
251  code_word <<= shift;
252  bits += shift;
253  if(bits >= 0 && c->buffer < c->end) {
254  code_word |= bytestream_get_be16(&c->buffer) << bits;
255  bits -= 16;
256  }
257  c->bits = bits;
258  return code_word;
259 }
260 
261 #if ARCH_ARM
262 #include "arm/vp56_arith.h"
263 #elif ARCH_X86
264 #include "x86/vp56_arith.h"
265 #endif
266 
267 #ifndef vp56_rac_get_prob
268 #define vp56_rac_get_prob vp56_rac_get_prob
270 {
271  unsigned int code_word = vp56_rac_renorm(c);
272  unsigned int low = 1 + (((c->high - 1) * prob) >> 8);
273  unsigned int low_shift = low << 16;
274  int bit = code_word >= low_shift;
275 
276  c->high = bit ? c->high - low : low;
277  c->code_word = bit ? code_word - low_shift : code_word;
278 
279  return bit;
280 }
281 #endif
282 
283 #ifndef vp56_rac_get_prob_branchy
284 // branchy variant, to be used where there's a branch based on the bit decoded
286 {
287  unsigned long code_word = vp56_rac_renorm(c);
288  unsigned low = 1 + (((c->high - 1) * prob) >> 8);
289  unsigned low_shift = low << 16;
290 
291  if (code_word >= low_shift) {
292  c->high -= low;
293  c->code_word = code_word - low_shift;
294  return 1;
295  }
296 
297  c->high = low;
298  c->code_word = code_word;
299  return 0;
300 }
301 #endif
302 
304 {
305  unsigned int code_word = vp56_rac_renorm(c);
306  /* equiprobable */
307  int low = (c->high + 1) >> 1;
308  unsigned int low_shift = low << 16;
309  int bit = code_word >= low_shift;
310  if (bit) {
311  c->high -= low;
312  code_word -= low_shift;
313  } else {
314  c->high = low;
315  }
316 
317  c->code_word = code_word;
318  return bit;
319 }
320 
321 // rounding is different than vp56_rac_get, is vp56_rac_get wrong?
323 {
324  return vp56_rac_get_prob(c, 128);
325 }
326 
328 {
329  int value = 0;
330 
331  while (bits--) {
332  value = (value << 1) | vp56_rac_get(c);
333  }
334 
335  return value;
336 }
337 
339 {
340  int value = 0;
341 
342  while (bits--) {
343  value = (value << 1) | vp8_rac_get(c);
344  }
345 
346  return value;
347 }
348 
349 // fixme: add 1 bit to all the calls to this?
351 {
352  int v;
353 
354  if (!vp8_rac_get(c))
355  return 0;
356 
357  v = vp8_rac_get_uint(c, bits);
358 
359  if (vp8_rac_get(c))
360  v = -v;
361 
362  return v;
363 }
364 
365 // P(7)
367 {
368  int v = vp56_rac_gets(c, 7) << 1;
369  return v + !v;
370 }
371 
373 {
374  int v = vp8_rac_get_uint(c, 7) << 1;
375  return v + !v;
376 }
377 
378 static av_always_inline
380  const VP56Tree *tree,
381  const uint8_t *probs)
382 {
383  while (tree->val > 0) {
384  if (vp56_rac_get_prob_branchy(c, probs[tree->prob_idx]))
385  tree += tree->val;
386  else
387  tree++;
388  }
389  return -tree->val;
390 }
391 
392 // how probabilities are associated with decisions is different I think
393 // well, the new scheme fits in the old but this way has one fewer branches per decision
394 static av_always_inline int vp8_rac_get_tree(VP56RangeCoder *c, const int8_t (*tree)[2],
395  const uint8_t *probs)
396 {
397  int i = 0;
398 
399  do {
400  i = tree[i][vp56_rac_get_prob(c, probs[i])];
401  } while (i > 0);
402 
403  return -i;
404 }
405 
406 // DCTextra
408 {
409  int v = 0;
410 
411  do {
412  v = (v<<1) + vp56_rac_get_prob(c, *prob++);
413  } while (*prob);
414 
415  return v;
416 }
417 
418 #endif /* AVCODEC_VP56_H */
VP56mb mb_type
Definition: vp56.h:159
static int shift(int a, int b)
Definition: sonic.c:82
unsigned int code_word
Definition: vp56.h:91
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
int(* VP56ParseCoeff)(VP56Context *s)
Definition: vp56.h:78
int(* VP56ParseCoeffModels)(VP56Context *s)
Definition: vp56.h:81
static av_always_inline int vp8_rac_get_tree(VP56RangeCoder *c, const int8_t(*tree)[2], const uint8_t *probs)
Definition: vp56.h:394
int deblock_filtering
Definition: vp56.h:171
VP3DSPContext vp3dsp
Definition: vp56.h:129
int vector_candidate_pos
Definition: vp56.h:167
Inter MB, no vector, from previous frame.
Definition: vp56.h:49
VP56ParseVectorAdjustment parse_vector_adjustment
Definition: vp56.h:190
int use_huffman
Definition: vp56.h:205
uint16_t dequant_ac
Definition: vp56.h:150
#define src
Definition: vp8dsp.c:254
VP56ParseCoeffModels parse_coeff_models
Definition: vp56.h:195
if it could not because there are no more frames
VP56ParseVectorModels parse_vector_models
Definition: vp56.h:194
int ff_vp56_init(AVCodecContext *avctx, int flip, int has_alpha)
Definition: vp56.c:776
int16_t y
Definition: vp56.h:68
int mb_height
Definition: vp56.h:145
void(* VP56ParseVectorModels)(VP56Context *s)
Definition: vp56.h:80
uint8_t
uint16_t dequant_dc
Definition: vp56.h:149
int mb_width
Definition: vp56.h:144
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
GLsizei GLboolean const GLfloat * value
Definition: opengl_enc.c:108
VP56DSPContext vp56dsp
Definition: vp56.h:130
int end_reached
Definition: vp56.h:92
#define DECLARE_ALIGNED(n, t, v)
Declare a variable that is aligned in memory.
Definition: mem.h:112
void ff_vp56_init_dequant(VP56Context *s, int quantizer)
Definition: vp56.c:34
bitstream reader API header.
static av_always_inline int vpX_rac_is_end(VP56RangeCoder *c)
vp5689 returns 1 if the end of the stream has been reached, 0 otherwise.
Definition: vp56.h:237
uint8_t * edge_emu_buffer
Definition: vp56.h:134
static av_always_inline int vp56_rac_get_tree(VP56RangeCoder *c, const VP56Tree *tree, const uint8_t *probs)
Definition: vp56.h:379
Inter MB, second vector, from golden frame.
Definition: vp56.h:58
VP56ParseCoeff parse_coeff
Definition: vp56.h:192
#define prob(name, subs,...)
Definition: cbs_vp9.c:374
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
static const uint16_t mask[17]
Definition: lzw.c:38
static void flip(AVCodecContext *avctx, AVFrame *frame)
Definition: rawdec.c:136
static av_always_inline int vp56_rac_get(VP56RangeCoder *c)
Definition: vp56.h:303
VP56mb
Definition: vp56.h:48
Definition: vp56.h:95
uint8_t type
Definition: vp56.h:102
uint8_t bits
Definition: vp3data.h:202
Inter MB, first vector, from previous frame.
Definition: vp56.h:52
int frbi
Definition: vp56.h:185
Definition: vlc.h:26
const uint8_t * end
Definition: vp56.h:90
Intra MB.
Definition: vp56.h:50
VP56RangeCoder cc
Definition: vp56.h:136
VP56Frame
Definition: vp56.h:40
VP56RangeCoder * ccp
Definition: vp56.h:137
int ff_vp56_init_range_decoder(VP56RangeCoder *c, const uint8_t *buf, int buf_size)
Definition: vp56rac.c:40
static av_unused int vp56_rac_gets_nn(VP56RangeCoder *c, int bits)
Definition: vp56.h:366
Definition: vp56.h:61
VP56Context * alpha_context
Definition: vp56.h:199
Inter MB, first vector, from golden frame.
Definition: vp56.h:57
Half-pel DSP context.
Definition: hpeldsp.h:45
void(* VP56Filter)(VP56Context *s, uint8_t *dst, uint8_t *src, int offset1, int offset2, ptrdiff_t stride, VP56mv mv, int mask, int select, int luma)
Definition: vp56.h:75
int8_t prob_idx
Definition: vp56.h:63
VP56RangeCoder c
Definition: vp56.h:135
static av_unused int vp8_rac_get_sint(VP56RangeCoder *c, int bits)
Definition: vp56.h:350
typedef void(APIENTRY *FF_PFNGLACTIVETEXTUREPROC)(GLenum texture)
VP56ParseHeader parse_header
Definition: vp56.h:196
#define s(width, name)
Definition: cbs_vp9.c:257
int filter_selection
Definition: vp56.h:172
#define vp56_rac_get_prob
Definition: vp56.h:268
VP56Macroblock * macroblocks
Definition: vp56.h:160
VP56RefDc * above_blocks
Definition: vp56.h:153
VP56Frame ref_frame
Definition: vp56.h:97
static const int8_t mv[256][2]
Definition: 4xm.c:77
static av_always_inline int vp56_rac_get_prob_branchy(VP56RangeCoder *c, int prob)
Definition: vp56.h:285
Inter MB, 4 vectors, from previous frame.
Definition: vp56.h:56
int quantizer
Definition: vp56.h:148
int discard_frame
Definition: vp56.h:213
Half-pel DSP functions.
Inter MB, no vector, from golden frame.
Definition: vp56.h:54
int ff_vp56_init_context(AVCodecContext *avctx, VP56Context *s, int flip, int has_alpha)
Definition: vp56.c:782
Libavcodec external API header.
Inter MB, second vector, from previous frame.
Definition: vp56.h:53
main external API structure.
Definition: avcodec.h:1566
static av_always_inline unsigned int vp56_rac_renorm(VP56RangeCoder *c)
Definition: vp56.h:244
int ff_vp56_free(AVCodecContext *avctx)
Definition: vp56.c:835
uint8_t not_null_dc
Definition: vp56.h:96
int sub_version
Definition: vp56.h:138
void * buf
Definition: avisynth_c.h:766
int bits
Definition: vp56.h:87
VP56DefaultModelsInit default_models_init
Definition: vp56.h:193
int have_undamaged_frame
Definition: vp56.h:212
int8_t val
Definition: vp56.h:62
Inter MB, above/left vector + delta, from previous frame.
Definition: vp56.h:51
static av_always_inline int vp8_rac_get_coeff(VP56RangeCoder *c, const uint8_t *prob)
Definition: vp56.h:407
int sample_variance_threshold
Definition: vp56.h:175
int ff_vp56_free_context(VP56Context *s)
Definition: vp56.c:841
VideoDSPContext vdsp
Definition: vp56.h:128
const uint8_t ff_vp56_norm_shift[256]
vp56 specific range coder implementation
Definition: vp56rac.c:25
static int vp8_rac_get_uint(VP56RangeCoder *c, int bits)
Definition: vp56.h:338
Definition: vp56.h:66
int ff_vp56_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: vp56.c:568
int srbi
Definition: vp56.h:186
const uint8_t * vp56_coord_div
Definition: vp56.h:189
int max_vector_length
Definition: vp56.h:174
GLint GLenum GLboolean GLsizei stride
Definition: opengl_enc.c:104
int
VP56mv mv
Definition: vp56.h:103
int filter_mode
Definition: vp56.h:173
int(* VP56ParseHeader)(VP56Context *s, const uint8_t *buf, int buf_size)
Definition: vp56.h:82
#define bit(string, value)
Definition: cbs_mpeg2.c:58
void(* VP56ParseVectorAdjustment)(VP56Context *s, VP56mv *vect)
Definition: vp56.h:73
int golden_frame
Definition: vp56.h:141
void(* VP56DefaultModelsInit)(VP56Context *s)
Definition: vp56.h:79
static av_always_inline int vp8_rac_get(VP56RangeCoder *c)
Definition: vp56.h:322
VP56Filter filter
Definition: vp56.h:191
Core video DSP helper functions.
int filter_header
Definition: vp56.h:170
int16_t dc_coeff
Definition: vp56.h:98
HpelDSPContext hdsp
Definition: vp56.h:127
Inter MB, above/left vector + delta, from golden frame.
Definition: vp56.h:55
VP56Model * modelp
Definition: vp56.h:201
int has_alpha
Definition: vp56.h:181
int flip
Definition: vp56.h:184
VP56Model model
Definition: vp56.h:202
uint8_t * edge_emu_buffer_alloc
Definition: vp56.h:133
static av_unused int vp8_rac_get_nn(VP56RangeCoder *c)
Definition: vp56.h:372
const uint8_t * buffer
Definition: vp56.h:89
#define av_always_inline
Definition: attributes.h:39
AVCodecContext * avctx
Definition: vp56.h:125
int high
Definition: vp56.h:86
#define stride
This structure stores compressed data.
Definition: avcodec.h:1455
#define av_unused
Definition: attributes.h:125
H264ChromaContext h264chroma
Definition: vp56.h:126
static int vp56_rac_gets(VP56RangeCoder *c, int bits)
Definition: vp56.h:327
GetBitContext gb
Definition: vp56.h:206