3 * VP5 and VP6 compatible video decoder (common features)
5 * Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org>
7 * This file is part of FFmpeg.
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.
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.
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
24 #ifndef AVCODEC_VP56_H
25 #define AVCODEC_VP56_H
30 #include "bytestream.h"
33 typedef struct vp56_context VP56Context;
34 typedef struct vp56_mv VP56mv;
36 typedef void (*VP56ParseVectorAdjustment)(VP56Context *s,
38 typedef void (*VP56Filter)(VP56Context *s, uint8_t *dst, uint8_t *src,
39 int offset1, int offset2, int stride,
40 VP56mv mv, int mask, int select, int luma);
41 typedef void (*VP56ParseCoeff)(VP56Context *s);
42 typedef void (*VP56DefaultModelsInit)(VP56Context *s);
43 typedef void (*VP56ParseVectorModels)(VP56Context *s);
44 typedef void (*VP56ParseCoeffModels)(VP56Context *s);
45 typedef int (*VP56ParseHeader)(VP56Context *s, const uint8_t *buf,
46 int buf_size, int *golden_frame);
51 const uint8_t *buffer;
53 unsigned long code_word;
73 uint8_t coeff_reorder[64]; /* used in vp6 only */
74 uint8_t coeff_index_to_pos[64]; /* used in vp6 only */
75 uint8_t vector_sig[2]; /* delta sign */
76 uint8_t vector_dct[2]; /* delta coding types */
77 uint8_t vector_pdi[2][2]; /* predefined delta init */
78 uint8_t vector_pdv[2][7]; /* predefined delta values */
79 uint8_t vector_fdv[2][8]; /* 8 bit delta value definition */
80 uint8_t coeff_dccv[2][11]; /* DC coeff value */
81 uint8_t coeff_ract[2][3][6][11]; /* Run/AC coding type and AC coeff value */
82 uint8_t coeff_acct[2][3][3][6][5];/* vp5 only AC coding type for coding group < 3 */
83 uint8_t coeff_dcct[2][36][5]; /* DC coeff coding type */
84 uint8_t coeff_runv[2][14]; /* run value (vp6 only) */
85 uint8_t mb_type[3][10][10]; /* model for decoding MB type */
86 uint8_t mb_types_stats[3][10][2];/* contextual, next MB type stats */
90 AVCodecContext *avctx;
92 VP56DSPContext vp56dsp;
96 uint8_t *edge_emu_buffer_alloc;
97 uint8_t *edge_emu_buffer;
106 int mb_width; /* number of horizontal MB */
107 int mb_height; /* number of vertical MB */
113 int8_t *qscale_table;
115 /* DC predictors management */
116 VP56RefDc *above_blocks;
117 VP56RefDc left_block[4];
118 int above_block_idx[6];
119 DCTELEM prev_dc[3][3]; /* [plan][ref_frame] */
121 /* blocks / macroblock */
123 VP56Macroblock *macroblocks;
124 DECLARE_ALIGNED(16, DCTELEM, block_coeff)[6][64];
127 VP56mv mv[6]; /* vectors for each block in MB */
128 VP56mv vector_candidate[2];
129 int vector_candidate_pos;
131 /* filtering hints */
132 int filter_header; /* used in vp6 only */
133 int deblock_filtering;
134 int filter_selection;
136 int max_vector_length;
137 int sample_variance_threshold;
139 uint8_t coeff_ctx[4][64]; /* used in vp5 only */
140 uint8_t coeff_ctx_last[4]; /* used in vp5 only */
144 /* upside-down flipping hints */
145 int flip; /* are we flipping ? */
146 int frbi; /* first row block index in MB */
147 int srbi; /* second row block index in MB */
148 int stride[4]; /* stride for each plan */
150 const uint8_t *vp56_coord_div;
151 VP56ParseVectorAdjustment parse_vector_adjustment;
153 VP56ParseCoeff parse_coeff;
154 VP56DefaultModelsInit default_models_init;
155 VP56ParseVectorModels parse_vector_models;
156 VP56ParseCoeffModels parse_coeff_models;
157 VP56ParseHeader parse_header;
162 /* huffman decoding */
167 VLC ract_vlc[2][3][6];
168 unsigned int nb_null[2][2]; /* number of consecutive NULL DC/AC */
172 void vp56_init(AVCodecContext *avctx, int flip, int has_alpha);
173 int vp56_free(AVCodecContext *avctx);
174 void vp56_init_dequant(VP56Context *s, int quantizer);
175 int vp56_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
180 * vp56 specific range coder implementation
183 static inline void vp56_init_range_decoder(VP56RangeCoder *c,
184 const uint8_t *buf, int buf_size)
189 c->end = buf + buf_size;
190 c->code_word = bytestream_get_be16(&c->buffer);
193 static inline int vp56_rac_get_prob(VP56RangeCoder *c, uint8_t prob)
195 unsigned int low = 1 + (((c->high - 1) * prob) >> 8);
196 unsigned int low_shift = low << 8;
197 int bit = c->code_word >= low_shift;
201 c->code_word -= low_shift;
207 while (c->high < 128) {
210 if (--c->bits == 0 && c->buffer < c->end) {
212 c->code_word |= *c->buffer++;
218 static inline int vp56_rac_get(VP56RangeCoder *c)
221 int low = (c->high + 1) >> 1;
222 unsigned int low_shift = low << 8;
223 int bit = c->code_word >= low_shift;
225 c->high = (c->high - low) << 1;
226 c->code_word -= low_shift;
233 if (--c->bits == 0 && c->buffer < c->end) {
235 c->code_word |= *c->buffer++;
240 // rounding is different than vp56_rac_get, is vp56_rac_get wrong?
241 static inline int vp8_rac_get(VP56RangeCoder *c)
243 return vp56_rac_get_prob(c, 128);
246 static inline int vp56_rac_gets(VP56RangeCoder *c, int bits)
251 value = (value << 1) | vp56_rac_get(c);
257 static inline int vp8_rac_get_uint(VP56RangeCoder *c, int bits)
262 value = (value << 1) | vp8_rac_get(c);
268 // fixme: add 1 bit to all the calls to this?
269 static inline int vp8_rac_get_sint(VP56RangeCoder *c, int bits)
276 v = vp8_rac_get_uint(c, bits);
285 static inline int vp56_rac_gets_nn(VP56RangeCoder *c, int bits)
287 int v = vp56_rac_gets(c, 7) << 1;
291 static inline int vp8_rac_get_nn(VP56RangeCoder *c)
293 int v = vp8_rac_get_uint(c, 7) << 1;
297 static inline int vp56_rac_get_tree(VP56RangeCoder *c,
298 const VP56Tree *tree,
299 const uint8_t *probs)
301 while (tree->val > 0) {
302 if (vp56_rac_get_prob(c, probs[tree->prob_idx]))
311 * This is identical to vp8_rac_get_tree except for the possibility of starting
312 * on a node other than the root node, needed for coeff decode where this is
313 * used to save a bit after a 0 token (by disallowing EOB to immediately follow.)
315 static inline int vp8_rac_get_tree_with_offset(VP56RangeCoder *c, const int8_t (*tree)[2],
316 const uint8_t *probs, int i)
319 i = tree[i][vp56_rac_get_prob(c, probs[i])];
325 // how probabilities are associated with decisions is different I think
326 // well, the new scheme fits in the old but this way has one fewer branches per decision
327 static inline int vp8_rac_get_tree(VP56RangeCoder *c, const int8_t (*tree)[2],
328 const uint8_t *probs)
330 return vp8_rac_get_tree_with_offset(c, tree, probs, 0);
334 static inline int vp8_rac_get_coeff(VP56RangeCoder *c, const uint8_t *prob)
339 v = (v<<1) + vp56_rac_get_prob(c, *prob++);
345 #endif /* AVCODEC_VP56_H */