2 * Audio and Video frame extraction
3 * Copyright (c) 2003 Fabrice Bellard
4 * Copyright (c) 2003 Michael Niedermayer
6 * This file is part of FFmpeg.
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26 #include "libavutil/atomic.h"
27 #include "libavutil/mem.h"
31 static AVCodecParser *av_first_parser = NULL;
33 AVCodecParser *av_parser_next(const AVCodecParser *p)
38 return av_first_parser;
41 void av_register_codec_parser(AVCodecParser *parser)
44 parser->next = av_first_parser;
45 } while (parser->next != avpriv_atomic_ptr_cas((void * volatile *)&av_first_parser, parser->next, parser));
48 AVCodecParserContext *av_parser_init(int codec_id)
50 AVCodecParserContext *s = NULL;
51 AVCodecParser *parser;
54 if (codec_id == AV_CODEC_ID_NONE)
57 for (parser = av_first_parser; parser; parser = parser->next) {
58 if (parser->codec_ids[0] == codec_id ||
59 parser->codec_ids[1] == codec_id ||
60 parser->codec_ids[2] == codec_id ||
61 parser->codec_ids[3] == codec_id ||
62 parser->codec_ids[4] == codec_id)
68 s = av_mallocz(sizeof(AVCodecParserContext));
72 s->priv_data = av_mallocz(parser->priv_data_size);
76 s->pict_type = AV_PICTURE_TYPE_I;
77 if (parser->parser_init) {
78 ret = parser->parser_init(s);
83 s->convergence_duration = 0;
84 s->dts_sync_point = INT_MIN;
85 s->dts_ref_dts_delta = INT_MIN;
86 s->pts_dts_delta = INT_MIN;
91 av_freep(&s->priv_data);
96 void ff_fetch_timestamp(AVCodecParserContext *s, int off, int remove)
101 s->pts = AV_NOPTS_VALUE;
104 for (i = 0; i < AV_PARSER_PTS_NB; i++) {
105 if (s->cur_offset + off >= s->cur_frame_offset[i] &&
106 (s->frame_offset < s->cur_frame_offset[i] ||
107 (!s->frame_offset && !s->next_frame_offset)) && // first field/frame
108 // check disabled since MPEG-TS does not send complete PES packets
109 /*s->next_frame_offset + off <*/ s->cur_frame_end[i]){
111 s->dts = s->cur_frame_dts[i];
112 s->pts = s->cur_frame_pts[i];
113 s->pos = s->cur_frame_pos[i];
114 s->offset = s->next_frame_offset - s->cur_frame_offset[i];
116 s->cur_frame_offset[i] = INT64_MAX;
117 if (s->cur_offset + off < s->cur_frame_end[i])
123 int av_parser_parse2(AVCodecParserContext *s, AVCodecContext *avctx,
124 uint8_t **poutbuf, int *poutbuf_size,
125 const uint8_t *buf, int buf_size,
126 int64_t pts, int64_t dts, int64_t pos)
129 uint8_t dummy_buf[FF_INPUT_BUFFER_PADDING_SIZE];
131 if (!(s->flags & PARSER_FLAG_FETCHED_OFFSET)) {
132 s->next_frame_offset =
134 s->flags |= PARSER_FLAG_FETCHED_OFFSET;
138 /* padding is always necessary even if EOF, so we add it here */
139 memset(dummy_buf, 0, sizeof(dummy_buf));
141 } else if (s->cur_offset + buf_size != s->cur_frame_end[s->cur_frame_start_index]) { /* skip remainder packets */
142 /* add a new packet descriptor */
143 i = (s->cur_frame_start_index + 1) & (AV_PARSER_PTS_NB - 1);
144 s->cur_frame_start_index = i;
145 s->cur_frame_offset[i] = s->cur_offset;
146 s->cur_frame_end[i] = s->cur_offset + buf_size;
147 s->cur_frame_pts[i] = pts;
148 s->cur_frame_dts[i] = dts;
149 s->cur_frame_pos[i] = pos;
152 if (s->fetch_timestamp) {
153 s->fetch_timestamp = 0;
154 s->last_pts = s->pts;
155 s->last_dts = s->dts;
156 s->last_pos = s->pos;
157 ff_fetch_timestamp(s, 0, 0);
159 /* WARNING: the returned index can be negative */
160 index = s->parser->parser_parse(s, avctx, (const uint8_t **) poutbuf,
161 poutbuf_size, buf, buf_size);
162 /* update the file pointer */
164 /* fill the data for the current frame */
165 s->frame_offset = s->next_frame_offset;
167 /* offset of the next frame */
168 s->next_frame_offset = s->cur_offset + index;
169 s->fetch_timestamp = 1;
173 s->cur_offset += index;
177 int av_parser_change(AVCodecParserContext *s, AVCodecContext *avctx,
178 uint8_t **poutbuf, int *poutbuf_size,
179 const uint8_t *buf, int buf_size, int keyframe)
181 if (s && s->parser->split) {
182 if (avctx->flags & CODEC_FLAG_GLOBAL_HEADER ||
183 avctx->flags2 & CODEC_FLAG2_LOCAL_HEADER) {
184 int i = s->parser->split(avctx, buf, buf_size);
190 /* cast to avoid warning about discarding qualifiers */
191 *poutbuf = (uint8_t *) buf;
192 *poutbuf_size = buf_size;
193 if (avctx->extradata) {
194 if (keyframe && (avctx->flags2 & CODEC_FLAG2_LOCAL_HEADER)) {
195 int size = buf_size + avctx->extradata_size;
197 *poutbuf_size = size;
198 *poutbuf = av_malloc(size + FF_INPUT_BUFFER_PADDING_SIZE);
200 memcpy(*poutbuf, avctx->extradata, avctx->extradata_size);
201 memcpy(*poutbuf + avctx->extradata_size, buf,
202 buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
210 void av_parser_close(AVCodecParserContext *s)
213 if (s->parser->parser_close)
214 s->parser->parser_close(s);
215 av_freep(&s->priv_data);
220 int ff_combine_frame(ParseContext *pc, int next,
221 const uint8_t **buf, int *buf_size)
224 av_dlog(NULL, "overread %d, state:%X next:%d index:%d o_index:%d\n",
225 pc->overread, pc->state, next, pc->index, pc->overread_index);
226 av_dlog(NULL, "%X %X %X %X\n",
227 (*buf)[0], (*buf)[1], (*buf)[2], (*buf)[3]);
230 /* Copy overread bytes from last frame into buffer. */
231 for (; pc->overread > 0; pc->overread--)
232 pc->buffer[pc->index++] = pc->buffer[pc->overread_index++];
234 /* flush remaining if EOF */
235 if (!*buf_size && next == END_NOT_FOUND)
238 pc->last_index = pc->index;
240 /* copy into buffer end return */
241 if (next == END_NOT_FOUND) {
242 void *new_buffer = av_fast_realloc(pc->buffer, &pc->buffer_size,
243 *buf_size + pc->index +
244 FF_INPUT_BUFFER_PADDING_SIZE);
248 return AVERROR(ENOMEM);
250 pc->buffer = new_buffer;
251 memcpy(&pc->buffer[pc->index], *buf, *buf_size);
252 pc->index += *buf_size;
257 pc->overread_index = pc->index + next;
259 /* append to buffer */
261 void *new_buffer = av_fast_realloc(pc->buffer, &pc->buffer_size,
263 FF_INPUT_BUFFER_PADDING_SIZE);
267 return AVERROR(ENOMEM);
269 pc->buffer = new_buffer;
270 if (next > -FF_INPUT_BUFFER_PADDING_SIZE)
271 memcpy(&pc->buffer[pc->index], *buf,
272 next + FF_INPUT_BUFFER_PADDING_SIZE);
277 /* store overread bytes */
278 for (; next < 0; next++) {
279 pc->state = pc->state << 8 | pc->buffer[pc->last_index + next];
280 pc->state64 = pc->state64 << 8 | pc->buffer[pc->last_index + next];
285 av_dlog(NULL, "overread %d, state:%X next:%d index:%d o_index:%d\n",
286 pc->overread, pc->state, next, pc->index, pc->overread_index);
287 av_dlog(NULL, "%X %X %X %X\n",
288 (*buf)[0], (*buf)[1], (*buf)[2], (*buf)[3]);
294 void ff_parse_close(AVCodecParserContext *s)
296 ParseContext *pc = s->priv_data;
298 av_freep(&pc->buffer);
301 int ff_mpeg4video_split(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
306 for (i = 0; i < buf_size; i++) {
307 state = state << 8 | buf[i];
308 if (state == 0x1B3 || state == 0x1B6)