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
26 #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)
43 parser->next = av_first_parser;
44 av_first_parser = parser;
47 AVCodecParserContext *av_parser_init(int codec_id)
49 AVCodecParserContext *s;
50 AVCodecParser *parser;
53 if (codec_id == AV_CODEC_ID_NONE)
56 for (parser = av_first_parser; parser != NULL; parser = parser->next) {
57 if (parser->codec_ids[0] == codec_id ||
58 parser->codec_ids[1] == codec_id ||
59 parser->codec_ids[2] == codec_id ||
60 parser->codec_ids[3] == codec_id ||
61 parser->codec_ids[4] == codec_id)
67 s = av_mallocz(sizeof(AVCodecParserContext));
71 if (parser->priv_data_size) {
72 s->priv_data = av_mallocz(parser->priv_data_size);
78 if (parser->parser_init) {
79 ret = parser->parser_init(s);
81 av_free(s->priv_data);
86 s->fetch_timestamp = 1;
87 s->pict_type = AV_PICTURE_TYPE_I;
89 s->convergence_duration = 0;
90 s->dts_sync_point = INT_MIN;
91 s->dts_ref_dts_delta = INT_MIN;
92 s->pts_dts_delta = INT_MIN;
98 void ff_fetch_timestamp(AVCodecParserContext *s, int off, int remove)
103 s->pts = AV_NOPTS_VALUE;
106 for (i = 0; i < AV_PARSER_PTS_NB; i++) {
107 if (s->cur_offset + off >= s->cur_frame_offset[i] &&
108 (s->frame_offset < s->cur_frame_offset[i] ||
109 (!s->frame_offset && !s->next_frame_offset)) &&
110 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 return AVERROR(ENOMEM);
202 memcpy(*poutbuf, avctx->extradata, avctx->extradata_size);
203 memcpy(*poutbuf + avctx->extradata_size, buf,
204 buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
212 void av_parser_close(AVCodecParserContext *s)
215 if (s->parser->parser_close)
216 s->parser->parser_close(s);
217 av_free(s->priv_data);
222 int ff_combine_frame(ParseContext *pc, int next,
223 const uint8_t **buf, int *buf_size)
226 ff_dlog(NULL, "overread %d, state:%X next:%d index:%d o_index:%d\n",
227 pc->overread, pc->state, next, pc->index, pc->overread_index);
228 ff_dlog(NULL, "%X %X %X %X\n",
229 (*buf)[0], (*buf)[1], (*buf)[2], (*buf)[3]);
232 /* Copy overread bytes from last frame into buffer. */
233 for (; pc->overread > 0; pc->overread--)
234 pc->buffer[pc->index++] = pc->buffer[pc->overread_index++];
236 /* flush remaining if EOF */
237 if (!*buf_size && next == END_NOT_FOUND)
240 pc->last_index = pc->index;
242 /* copy into buffer end return */
243 if (next == END_NOT_FOUND) {
244 void *new_buffer = av_fast_realloc(pc->buffer, &pc->buffer_size,
245 *buf_size + pc->index +
246 FF_INPUT_BUFFER_PADDING_SIZE);
249 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);
266 return AVERROR(ENOMEM);
267 pc->buffer = new_buffer;
268 if (next > -FF_INPUT_BUFFER_PADDING_SIZE)
269 memcpy(&pc->buffer[pc->index], *buf,
270 next + FF_INPUT_BUFFER_PADDING_SIZE);
275 /* store overread bytes */
276 for (; next < 0; next++) {
277 pc->state = pc->state << 8 | pc->buffer[pc->last_index + next];
278 pc->state64 = pc->state64 << 8 | pc->buffer[pc->last_index + next];
283 ff_dlog(NULL, "overread %d, state:%X next:%d index:%d o_index:%d\n",
284 pc->overread, pc->state, next, pc->index, pc->overread_index);
285 ff_dlog(NULL, "%X %X %X %X\n",
286 (*buf)[0], (*buf)[1], (*buf)[2], (*buf)[3]);
292 void ff_parse_close(AVCodecParserContext *s)
294 ParseContext *pc = s->priv_data;
296 av_freep(&pc->buffer);
299 int ff_mpeg4video_split(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
304 for (i = 0; i < buf_size; i++) {
305 state = state << 8 | buf[i];
306 if (state == 0x1B3 || state == 0x1B6)