avcodec: Add picture structure information to AVCodecParserContext.
[libav.git] / libavcodec / h264_parser.c
CommitLineData
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1/*
2 * H.26L/H.264/AVC/JVT/14496-10/... parser
3 * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
4 *
2912e87a 5 * This file is part of Libav.
26b4fe82 6 *
2912e87a 7 * Libav is free software; you can redistribute it and/or
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8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
2912e87a 12 * Libav is distributed in the hope that it will be useful,
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13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
2912e87a 18 * License along with Libav; if not, write to the Free Software
26b4fe82 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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20 */
21
22/**
ba87f080 23 * @file
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24 * H.264 / AVC / MPEG4 part10 parser.
25 * @author Michael Niedermayer <michaelni@gmx.at>
26 */
27
6fee1b90 28#include "libavutil/attributes.h"
26b4fe82 29#include "parser.h"
ff6474dd
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30#include "h264data.h"
31#include "golomb.h"
f1e93986 32#include "internal.h"
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33
34#include <assert.h>
35
36
088f38a4 37static int h264_find_frame_end(H264Context *h, const uint8_t *buf, int buf_size)
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38{
39 int i;
40 uint32_t state;
2c541554 41 ParseContext *pc = &h->parse_context;
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42// mb_addr= pc->mb_addr - 1;
43 state= pc->state;
44 if(state>13)
45 state= 7;
46
47 for(i=0; i<buf_size; i++){
48 if(state==7){
b250f9c6 49#if HAVE_FAST_UNALIGNED
e4f1ec3a
MN
50 /* we check i<buf_size instead of i+3/7 because its simpler
51 * and there should be FF_INPUT_BUFFER_PADDING_SIZE bytes at the end
52 */
b250f9c6 53# if HAVE_FAST_64BIT
4d8eb2e8 54 while(i<buf_size && !((~*(const uint64_t*)(buf+i) & (*(const uint64_t*)(buf+i) - 0x0101010101010101ULL)) & 0x8080808080808080ULL))
5cb5023c
MN
55 i+=8;
56# else
4d8eb2e8 57 while(i<buf_size && !((~*(const uint32_t*)(buf+i) & (*(const uint32_t*)(buf+i) - 0x01010101U)) & 0x80808080U))
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58 i+=4;
59# endif
60#endif
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61 for(; i<buf_size; i++){
62 if(!buf[i]){
63 state=2;
64 break;
65 }
66 }
67 }else if(state<=2){
68 if(buf[i]==1) state^= 5; //2->7, 1->4, 0->5
69 else if(buf[i]) state = 7;
70 else state>>=1; //2->1, 1->0, 0->0
71 }else if(state<=5){
72 int v= buf[i] & 0x1F;
9e85f9c5 73 if(v==6 || v==7 || v==8 || v==9){
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74 if(pc->frame_start_found){
75 i++;
9aa1cfec 76 goto found;
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77 }
78 }else if(v==1 || v==2 || v==5){
79 if(pc->frame_start_found){
80 state+=8;
81 continue;
82 }else
83 pc->frame_start_found = 1;
84 }
85 state= 7;
86 }else{
87 if(buf[i] & 0x80)
88 goto found;
89 state= 7;
90 }
91 }
92 pc->state= state;
93 return END_NOT_FOUND;
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94
95found:
96 pc->state=7;
97 pc->frame_start_found= 0;
98 return i-(state&5);
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99}
100
adbfc605 101/**
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102 * Parse NAL units of found picture and decode some basic information.
103 *
104 * @param s parser context.
105 * @param avctx codec context.
106 * @param buf buffer with field/frame data.
107 * @param buf_size size of the buffer.
108 */
109static inline int parse_nal_units(AVCodecParserContext *s,
110 AVCodecContext *avctx,
111 const uint8_t *buf, int buf_size)
112{
113 H264Context *h = s->priv_data;
114 const uint8_t *buf_end = buf + buf_size;
96c3da93 115 unsigned int pps_id;
ff6474dd 116 unsigned int slice_type;
8fa0ae06 117 int state = -1;
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IS
118 const uint8_t *ptr;
119
120 /* set some sane default values */
975a1447 121 s->pict_type = AV_PICTURE_TYPE_I;
0ed260c7 122 s->key_frame = 0;
ff6474dd 123
2c541554 124 h->avctx= avctx;
0ed260c7 125 h->sei_recovery_frame_cnt = -1;
c733922e
IS
126 h->sei_dpb_output_delay = 0;
127 h->sei_cpb_removal_delay = -1;
128 h->sei_buffering_period_present = 0;
ff6474dd 129
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BC
130 if (!buf_size)
131 return 0;
132
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133 for(;;) {
134 int src_length, dst_length, consumed;
f1e93986 135 buf = avpriv_find_start_code(buf, buf_end, &state);
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136 if(buf >= buf_end)
137 break;
138 --buf;
139 src_length = buf_end - buf;
140 switch (state & 0x1f) {
141 case NAL_SLICE:
142 case NAL_IDR_SLICE:
143 // Do not walk the whole buffer just to decode slice header
144 if (src_length > 20)
145 src_length = 20;
146 break;
147 }
358ea75e 148 ptr= ff_h264_decode_nal(h, buf, &dst_length, &consumed, src_length);
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149 if (ptr==NULL || dst_length < 0)
150 break;
151
2c541554 152 init_get_bits(&h->gb, ptr, 8*dst_length);
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153 switch(h->nal_unit_type) {
154 case NAL_SPS:
155 ff_h264_decode_seq_parameter_set(h);
156 break;
157 case NAL_PPS:
2c541554 158 ff_h264_decode_picture_parameter_set(h, h->gb.size_in_bits);
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159 break;
160 case NAL_SEI:
161 ff_h264_decode_sei(h);
162 break;
163 case NAL_IDR_SLICE:
0ed260c7
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164 s->key_frame = 1;
165 /* fall through */
ff6474dd 166 case NAL_SLICE:
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167 get_ue_golomb(&h->gb); // skip first_mb_in_slice
168 slice_type = get_ue_golomb_31(&h->gb);
ff6474dd 169 s->pict_type = golomb_to_pict_type[slice_type % 5];
0ed260c7
IS
170 if (h->sei_recovery_frame_cnt >= 0) {
171 /* key frame, since recovery_frame_cnt is set */
172 s->key_frame = 1;
173 }
2c541554 174 pps_id= get_ue_golomb(&h->gb);
96c3da93 175 if(pps_id>=MAX_PPS_COUNT) {
2c541554 176 av_log(h->avctx, AV_LOG_ERROR, "pps_id out of range\n");
96c3da93
IS
177 return -1;
178 }
179 if(!h->pps_buffers[pps_id]) {
2c541554 180 av_log(h->avctx, AV_LOG_ERROR, "non-existing PPS referenced\n");
96c3da93
IS
181 return -1;
182 }
183 h->pps= *h->pps_buffers[pps_id];
184 if(!h->sps_buffers[h->pps.sps_id]) {
2c541554 185 av_log(h->avctx, AV_LOG_ERROR, "non-existing SPS referenced\n");
96c3da93
IS
186 return -1;
187 }
188 h->sps = *h->sps_buffers[h->pps.sps_id];
2c541554 189 h->frame_num = get_bits(&h->gb, h->sps.log2_max_frame_num);
96c3da93 190
fe9a3fbe 191 avctx->profile = ff_h264_get_profile(&h->sps);
dd0cd3d2
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192 avctx->level = h->sps.level_idc;
193
96c3da93 194 if(h->sps.frame_mbs_only_flag){
2c541554 195 h->picture_structure= PICT_FRAME;
96c3da93 196 }else{
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AK
197 if(get_bits1(&h->gb)) { //field_pic_flag
198 h->picture_structure= PICT_TOP_FIELD + get_bits1(&h->gb); //bottom_field_flag
96c3da93 199 } else {
2c541554 200 h->picture_structure= PICT_FRAME;
96c3da93
IS
201 }
202 }
203
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IS
204 if(h->sps.pic_struct_present_flag) {
205 switch (h->sei_pic_struct) {
206 case SEI_PIC_STRUCT_TOP_FIELD:
207 case SEI_PIC_STRUCT_BOTTOM_FIELD:
fc9fe428 208 s->repeat_pict = 0;
346db3ef
IS
209 break;
210 case SEI_PIC_STRUCT_FRAME:
211 case SEI_PIC_STRUCT_TOP_BOTTOM:
212 case SEI_PIC_STRUCT_BOTTOM_TOP:
fc9fe428 213 s->repeat_pict = 1;
346db3ef
IS
214 break;
215 case SEI_PIC_STRUCT_TOP_BOTTOM_TOP:
216 case SEI_PIC_STRUCT_BOTTOM_TOP_BOTTOM:
fc9fe428 217 s->repeat_pict = 2;
346db3ef
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218 break;
219 case SEI_PIC_STRUCT_FRAME_DOUBLING:
fc9fe428 220 s->repeat_pict = 3;
346db3ef
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221 break;
222 case SEI_PIC_STRUCT_FRAME_TRIPLING:
fc9fe428 223 s->repeat_pict = 5;
346db3ef
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224 break;
225 default:
2c541554 226 s->repeat_pict = h->picture_structure == PICT_FRAME ? 1 : 0;
346db3ef
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227 break;
228 }
229 } else {
2c541554 230 s->repeat_pict = h->picture_structure == PICT_FRAME ? 1 : 0;
346db3ef
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231 }
232
ff6474dd
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233 return 0; /* no need to evaluate the rest */
234 }
235 buf += consumed;
236 }
237 /* didn't find a picture! */
2c541554 238 av_log(h->avctx, AV_LOG_ERROR, "missing picture in access unit\n");
ff6474dd
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239 return -1;
240}
241
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242static int h264_parse(AVCodecParserContext *s,
243 AVCodecContext *avctx,
244 const uint8_t **poutbuf, int *poutbuf_size,
245 const uint8_t *buf, int buf_size)
246{
247 H264Context *h = s->priv_data;
2c541554 248 ParseContext *pc = &h->parse_context;
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249 int next;
250
82f1ffc7
HC
251 if (!h->got_first) {
252 h->got_first = 1;
23584bec 253 if (avctx->extradata_size) {
2c541554 254 h->avctx = avctx;
790a367d
RT
255 // must be done like in the decoder.
256 // otherwise opening the parser, creating extradata,
257 // and then closing and opening again
258 // will cause has_b_frames to be always set.
259 // NB: estimate_timings_from_pts behaves exactly like this.
260 if (!avctx->has_b_frames)
2c541554 261 h->low_delay = 1;
23584bec
HC
262 ff_h264_decode_extradata(h);
263 }
264 }
265
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266 if(s->flags & PARSER_FLAG_COMPLETE_FRAMES){
267 next= buf_size;
268 }else{
088f38a4 269 next = h264_find_frame_end(h, buf, buf_size);
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270
271 if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
272 *poutbuf = NULL;
273 *poutbuf_size = 0;
274 return buf_size;
275 }
276
277 if(next<0 && next != END_NOT_FOUND){
278 assert(pc->last_index + next >= 0 );
088f38a4 279 h264_find_frame_end(h, &pc->buffer[pc->last_index + next], -next); // update state
26b4fe82 280 }
a26ce1e2 281 }
ff6474dd 282
25f05ddb 283 parse_nal_units(s, avctx, buf, buf_size);
c733922e 284
25f05ddb
PL
285 if (h->sei_cpb_removal_delay >= 0) {
286 s->dts_sync_point = h->sei_buffering_period_present;
287 s->dts_ref_dts_delta = h->sei_cpb_removal_delay;
288 s->pts_dts_delta = h->sei_dpb_output_delay;
289 } else {
290 s->dts_sync_point = INT_MIN;
291 s->dts_ref_dts_delta = INT_MIN;
292 s->pts_dts_delta = INT_MIN;
293 }
294
295 if (s->flags & PARSER_FLAG_ONCE) {
296 s->flags &= PARSER_FLAG_COMPLETE_FRAMES;
297 }
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298
299 *poutbuf = buf;
300 *poutbuf_size = buf_size;
301 return next;
302}
303
304static int h264_split(AVCodecContext *avctx,
305 const uint8_t *buf, int buf_size)
306{
307 int i;
308 uint32_t state = -1;
309 int has_sps= 0;
310
311 for(i=0; i<=buf_size; i++){
312 if((state&0xFFFFFF1F) == 0x107)
313 has_sps=1;
314/* if((state&0xFFFFFF1F) == 0x101 || (state&0xFFFFFF1F) == 0x102 || (state&0xFFFFFF1F) == 0x105){
315 }*/
316 if((state&0xFFFFFF00) == 0x100 && (state&0xFFFFFF1F) != 0x107 && (state&0xFFFFFF1F) != 0x108 && (state&0xFFFFFF1F) != 0x109){
317 if(has_sps){
318 while(i>4 && buf[i-5]==0) i--;
319 return i-4;
320 }
321 }
322 if (i<buf_size)
323 state= (state<<8) | buf[i];
324 }
325 return 0;
326}
327
dd990075 328static void close(AVCodecParserContext *s)
3ee4f5e4
MN
329{
330 H264Context *h = s->priv_data;
2c541554 331 ParseContext *pc = &h->parse_context;
3ee4f5e4
MN
332
333 av_free(pc->buffer);
15861962 334 ff_h264_free_context(h);
3ee4f5e4
MN
335}
336
6fee1b90 337static av_cold int init(AVCodecParserContext *s)
e9ca315d
RC
338{
339 H264Context *h = s->priv_data;
340 h->thread_context[0] = h;
2c541554 341 h->slice_context_count = 1;
e9ca315d
RC
342 return 0;
343}
26b4fe82 344
d36beb3f 345AVCodecParser ff_h264_parser = {
36ef5369 346 .codec_ids = { AV_CODEC_ID_H264 },
5511ad14
AK
347 .priv_data_size = sizeof(H264Context),
348 .parser_init = init,
349 .parser_parse = h264_parse,
350 .parser_close = close,
351 .split = h264_split,
26b4fe82 352};