2 * Audio and Video frame extraction
3 * Copyright (c) 2003 Fabrice Bellard
4 * Copyright (c) 2003 Michael Niedermayer
6 * This file is part of Libav.
8 * Libav 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 * Libav 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 Libav; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
27 #include "libavutil/internal.h"
28 #include "libavutil/mem.h"
33 static AVCodecParser *av_first_parser = NULL;
35 AVCodecParser *av_parser_next(const AVCodecParser *p)
40 return av_first_parser;
43 void av_register_codec_parser(AVCodecParser *parser)
45 parser->next = av_first_parser;
46 av_first_parser = parser;
49 AVCodecParserContext *av_parser_init(int codec_id)
51 AVCodecParserContext *s;
52 AVCodecParser *parser;
55 if (codec_id == AV_CODEC_ID_NONE)
58 for (parser = av_first_parser; parser != NULL; parser = parser->next) {
59 if (parser->codec_ids[0] == codec_id ||
60 parser->codec_ids[1] == codec_id ||
61 parser->codec_ids[2] == codec_id ||
62 parser->codec_ids[3] == codec_id ||
63 parser->codec_ids[4] == codec_id)
69 s = av_mallocz(sizeof(AVCodecParserContext));
73 if (parser->priv_data_size) {
74 s->priv_data = av_mallocz(parser->priv_data_size);
80 if (parser->parser_init) {
81 ret = parser->parser_init(s);
83 av_free(s->priv_data);
88 s->fetch_timestamp = 1;
89 s->pict_type = AV_PICTURE_TYPE_I;
91 #if FF_API_CONVERGENCE_DURATION
92 FF_DISABLE_DEPRECATION_WARNINGS
93 s->convergence_duration = 0;
94 FF_ENABLE_DEPRECATION_WARNINGS
96 s->dts_sync_point = INT_MIN;
97 s->dts_ref_dts_delta = INT_MIN;
98 s->pts_dts_delta = INT_MIN;
104 void ff_fetch_timestamp(AVCodecParserContext *s, int off, int remove)
109 s->pts = AV_NOPTS_VALUE;
112 for (i = 0; i < AV_PARSER_PTS_NB; i++) {
113 if (s->cur_offset + off >= s->cur_frame_offset[i] &&
114 (s->frame_offset < s->cur_frame_offset[i] ||
115 (!s->frame_offset && !s->next_frame_offset)) &&
116 s->cur_frame_end[i]) {
117 s->dts = s->cur_frame_dts[i];
118 s->pts = s->cur_frame_pts[i];
119 s->pos = s->cur_frame_pos[i];
120 s->offset = s->next_frame_offset - s->cur_frame_offset[i];
122 s->cur_frame_offset[i] = INT64_MAX;
123 if (s->cur_offset + off < s->cur_frame_end[i])
129 int av_parser_parse2(AVCodecParserContext *s, AVCodecContext *avctx,
130 uint8_t **poutbuf, int *poutbuf_size,
131 const uint8_t *buf, int buf_size,
132 int64_t pts, int64_t dts, int64_t pos)
135 uint8_t dummy_buf[AV_INPUT_BUFFER_PADDING_SIZE];
137 if (!(s->flags & PARSER_FLAG_FETCHED_OFFSET)) {
138 s->next_frame_offset =
140 s->flags |= PARSER_FLAG_FETCHED_OFFSET;
144 /* padding is always necessary even if EOF, so we add it here */
145 memset(dummy_buf, 0, sizeof(dummy_buf));
147 } else if (s->cur_offset + buf_size != s->cur_frame_end[s->cur_frame_start_index]) { /* skip remainder packets */
148 /* add a new packet descriptor */
149 i = (s->cur_frame_start_index + 1) & (AV_PARSER_PTS_NB - 1);
150 s->cur_frame_start_index = i;
151 s->cur_frame_offset[i] = s->cur_offset;
152 s->cur_frame_end[i] = s->cur_offset + buf_size;
153 s->cur_frame_pts[i] = pts;
154 s->cur_frame_dts[i] = dts;
155 s->cur_frame_pos[i] = pos;
158 if (s->fetch_timestamp) {
159 s->fetch_timestamp = 0;
160 s->last_pts = s->pts;
161 s->last_dts = s->dts;
162 s->last_pos = s->pos;
163 ff_fetch_timestamp(s, 0, 0);
165 /* WARNING: the returned index can be negative */
166 index = s->parser->parser_parse(s, avctx, (const uint8_t **) poutbuf,
167 poutbuf_size, buf, buf_size);
168 /* update the file pointer */
170 /* fill the data for the current frame */
171 s->frame_offset = s->next_frame_offset;
173 /* offset of the next frame */
174 s->next_frame_offset = s->cur_offset + index;
175 s->fetch_timestamp = 1;
179 s->cur_offset += index;
183 int av_parser_change(AVCodecParserContext *s, AVCodecContext *avctx,
184 uint8_t **poutbuf, int *poutbuf_size,
185 const uint8_t *buf, int buf_size, int keyframe)
187 if (s && s->parser->split) {
188 if (avctx->flags & AV_CODEC_FLAG_GLOBAL_HEADER ||
189 avctx->flags2 & AV_CODEC_FLAG2_LOCAL_HEADER) {
190 int i = s->parser->split(avctx, buf, buf_size);
196 /* cast to avoid warning about discarding qualifiers */
197 *poutbuf = (uint8_t *) buf;
198 *poutbuf_size = buf_size;
199 if (avctx->extradata) {
200 if (keyframe && (avctx->flags2 & AV_CODEC_FLAG2_LOCAL_HEADER)) {
201 int size = buf_size + avctx->extradata_size;
203 *poutbuf_size = size;
204 *poutbuf = av_malloc(size + AV_INPUT_BUFFER_PADDING_SIZE);
206 return AVERROR(ENOMEM);
208 memcpy(*poutbuf, avctx->extradata, avctx->extradata_size);
209 memcpy(*poutbuf + avctx->extradata_size, buf,
210 buf_size + AV_INPUT_BUFFER_PADDING_SIZE);
218 void av_parser_close(AVCodecParserContext *s)
221 if (s->parser->parser_close)
222 s->parser->parser_close(s);
223 av_free(s->priv_data);
228 int ff_combine_frame(ParseContext *pc, int next,
229 const uint8_t **buf, int *buf_size)
232 ff_dlog(NULL, "overread %d, state:%"PRIX32" next:%d index:%d o_index:%d\n",
233 pc->overread, pc->state, next, pc->index, pc->overread_index);
234 ff_dlog(NULL, "%X %X %X %X\n",
235 (*buf)[0], (*buf)[1], (*buf)[2], (*buf)[3]);
238 /* Copy overread bytes from last frame into buffer. */
239 for (; pc->overread > 0; pc->overread--)
240 pc->buffer[pc->index++] = pc->buffer[pc->overread_index++];
242 /* flush remaining if EOF */
243 if (!*buf_size && next == END_NOT_FOUND)
246 pc->last_index = pc->index;
248 /* copy into buffer end return */
249 if (next == END_NOT_FOUND) {
250 void *new_buffer = av_fast_realloc(pc->buffer, &pc->buffer_size,
251 *buf_size + pc->index +
252 AV_INPUT_BUFFER_PADDING_SIZE);
255 return AVERROR(ENOMEM);
256 pc->buffer = new_buffer;
257 memcpy(&pc->buffer[pc->index], *buf, *buf_size);
258 pc->index += *buf_size;
263 pc->overread_index = pc->index + next;
265 /* append to buffer */
267 void *new_buffer = av_fast_realloc(pc->buffer, &pc->buffer_size,
269 AV_INPUT_BUFFER_PADDING_SIZE);
272 return AVERROR(ENOMEM);
273 pc->buffer = new_buffer;
274 if (next > -AV_INPUT_BUFFER_PADDING_SIZE)
275 memcpy(&pc->buffer[pc->index], *buf,
276 next + AV_INPUT_BUFFER_PADDING_SIZE);
281 /* store overread bytes */
282 for (; next < 0; next++) {
283 pc->state = pc->state << 8 | pc->buffer[pc->last_index + next];
284 pc->state64 = pc->state64 << 8 | pc->buffer[pc->last_index + next];
289 ff_dlog(NULL, "overread %d, state:%"PRIX32" next:%d index:%d o_index:%d\n",
290 pc->overread, pc->state, next, pc->index, pc->overread_index);
291 ff_dlog(NULL, "%X %X %X %X\n",
292 (*buf)[0], (*buf)[1], (*buf)[2], (*buf)[3]);
298 void ff_parse_close(AVCodecParserContext *s)
300 ParseContext *pc = s->priv_data;
302 av_freep(&pc->buffer);
305 int ff_mpeg4video_split(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
310 for (i = 0; i < buf_size; i++) {
311 state = state << 8 | buf[i];
312 if (state == 0x1B3 || state == 0x1B6)