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"
30 static AVCodecParser *av_first_parser = NULL;
32 AVCodecParser *av_parser_next(AVCodecParser *p)
37 return av_first_parser;
40 void av_register_codec_parser(AVCodecParser *parser)
42 parser->next = av_first_parser;
43 av_first_parser = parser;
46 AVCodecParserContext *av_parser_init(int codec_id)
48 AVCodecParserContext *s;
49 AVCodecParser *parser;
52 if (codec_id == AV_CODEC_ID_NONE)
55 for (parser = av_first_parser; parser != NULL; parser = parser->next) {
56 if (parser->codec_ids[0] == codec_id ||
57 parser->codec_ids[1] == codec_id ||
58 parser->codec_ids[2] == codec_id ||
59 parser->codec_ids[3] == codec_id ||
60 parser->codec_ids[4] == codec_id)
66 s = av_mallocz(sizeof(AVCodecParserContext));
70 if (parser->priv_data_size) {
71 s->priv_data = av_mallocz(parser->priv_data_size);
77 if (parser->parser_init) {
78 ret = parser->parser_init(s);
80 av_free(s->priv_data);
85 s->fetch_timestamp = 1;
86 s->pict_type = AV_PICTURE_TYPE_I;
88 s->convergence_duration = 0;
89 s->dts_sync_point = INT_MIN;
90 s->dts_ref_dts_delta = INT_MIN;
91 s->pts_dts_delta = INT_MIN;
95 void ff_fetch_timestamp(AVCodecParserContext *s, int off, int remove)
100 s->pts = AV_NOPTS_VALUE;
103 for (i = 0; i < AV_PARSER_PTS_NB; i++) {
104 if (s->cur_offset + off >= s->cur_frame_offset[i] &&
105 (s->frame_offset < s->cur_frame_offset[i] ||
106 (!s->frame_offset && !s->next_frame_offset)) &&
107 s->cur_frame_end[i]) {
108 s->dts = s->cur_frame_dts[i];
109 s->pts = s->cur_frame_pts[i];
110 s->pos = s->cur_frame_pos[i];
111 s->offset = s->next_frame_offset - s->cur_frame_offset[i];
113 s->cur_frame_offset[i] = INT64_MAX;
114 if (s->cur_offset + off < s->cur_frame_end[i])
120 int av_parser_parse2(AVCodecParserContext *s, AVCodecContext *avctx,
121 uint8_t **poutbuf, int *poutbuf_size,
122 const uint8_t *buf, int buf_size,
123 int64_t pts, int64_t dts, int64_t pos)
126 uint8_t dummy_buf[FF_INPUT_BUFFER_PADDING_SIZE];
128 if (!(s->flags & PARSER_FLAG_FETCHED_OFFSET)) {
129 s->next_frame_offset =
131 s->flags |= PARSER_FLAG_FETCHED_OFFSET;
135 /* padding is always necessary even if EOF, so we add it here */
136 memset(dummy_buf, 0, sizeof(dummy_buf));
138 } else if (s->cur_offset + buf_size != s->cur_frame_end[s->cur_frame_start_index]) { /* skip remainder packets */
139 /* add a new packet descriptor */
140 i = (s->cur_frame_start_index + 1) & (AV_PARSER_PTS_NB - 1);
141 s->cur_frame_start_index = i;
142 s->cur_frame_offset[i] = s->cur_offset;
143 s->cur_frame_end[i] = s->cur_offset + buf_size;
144 s->cur_frame_pts[i] = pts;
145 s->cur_frame_dts[i] = dts;
146 s->cur_frame_pos[i] = pos;
149 if (s->fetch_timestamp) {
150 s->fetch_timestamp = 0;
151 s->last_pts = s->pts;
152 s->last_dts = s->dts;
153 s->last_pos = s->pos;
154 ff_fetch_timestamp(s, 0, 0);
156 /* WARNING: the returned index can be negative */
157 index = s->parser->parser_parse(s, avctx, (const uint8_t **) poutbuf,
158 poutbuf_size, buf, buf_size);
159 /* update the file pointer */
161 /* fill the data for the current frame */
162 s->frame_offset = s->next_frame_offset;
164 /* offset of the next frame */
165 s->next_frame_offset = s->cur_offset + index;
166 s->fetch_timestamp = 1;
170 s->cur_offset += index;
174 int av_parser_change(AVCodecParserContext *s, AVCodecContext *avctx,
175 uint8_t **poutbuf, int *poutbuf_size,
176 const uint8_t *buf, int buf_size, int keyframe)
178 if (s && s->parser->split) {
179 if (avctx->flags & CODEC_FLAG_GLOBAL_HEADER ||
180 avctx->flags2 & CODEC_FLAG2_LOCAL_HEADER) {
181 int i = s->parser->split(avctx, buf, buf_size);
187 /* cast to avoid warning about discarding qualifiers */
188 *poutbuf = (uint8_t *) buf;
189 *poutbuf_size = buf_size;
190 if (avctx->extradata) {
191 if (keyframe && (avctx->flags2 & CODEC_FLAG2_LOCAL_HEADER)) {
192 int size = buf_size + avctx->extradata_size;
194 *poutbuf_size = size;
195 *poutbuf = av_malloc(size + FF_INPUT_BUFFER_PADDING_SIZE);
197 memcpy(*poutbuf, avctx->extradata, avctx->extradata_size);
198 memcpy(*poutbuf + avctx->extradata_size, buf,
199 buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
207 void av_parser_close(AVCodecParserContext *s)
210 if (s->parser->parser_close)
211 s->parser->parser_close(s);
212 av_free(s->priv_data);
217 int ff_combine_frame(ParseContext *pc, int next,
218 const uint8_t **buf, int *buf_size)
221 av_dlog(NULL, "overread %d, state:%X next:%d index:%d o_index:%d\n",
222 pc->overread, pc->state, next, pc->index, pc->overread_index);
223 av_dlog(NULL, "%X %X %X %X\n",
224 (*buf)[0], (*buf)[1], (*buf)[2], (*buf)[3]);
227 /* Copy overread bytes from last frame into buffer. */
228 for (; pc->overread > 0; pc->overread--)
229 pc->buffer[pc->index++] = pc->buffer[pc->overread_index++];
231 /* flush remaining if EOF */
232 if (!*buf_size && next == END_NOT_FOUND)
235 pc->last_index = pc->index;
237 /* copy into buffer end return */
238 if (next == END_NOT_FOUND) {
239 void *new_buffer = av_fast_realloc(pc->buffer, &pc->buffer_size,
240 *buf_size + pc->index +
241 FF_INPUT_BUFFER_PADDING_SIZE);
244 return AVERROR(ENOMEM);
245 pc->buffer = new_buffer;
246 memcpy(&pc->buffer[pc->index], *buf, *buf_size);
247 pc->index += *buf_size;
252 pc->overread_index = pc->index + next;
254 /* append to buffer */
256 void *new_buffer = av_fast_realloc(pc->buffer, &pc->buffer_size,
258 FF_INPUT_BUFFER_PADDING_SIZE);
261 return AVERROR(ENOMEM);
262 pc->buffer = new_buffer;
263 if (next > -FF_INPUT_BUFFER_PADDING_SIZE)
264 memcpy(&pc->buffer[pc->index], *buf,
265 next + FF_INPUT_BUFFER_PADDING_SIZE);
270 /* store overread bytes */
271 for (; next < 0; next++) {
272 pc->state = pc->state << 8 | pc->buffer[pc->last_index + next];
273 pc->state64 = pc->state64 << 8 | pc->buffer[pc->last_index + next];
278 av_dlog(NULL, "overread %d, state:%X next:%d index:%d o_index:%d\n",
279 pc->overread, pc->state, next, pc->index, pc->overread_index);
280 av_dlog(NULL, "%X %X %X %X\n",
281 (*buf)[0], (*buf)[1], (*buf)[2], (*buf)[3]);
287 void ff_parse_close(AVCodecParserContext *s)
289 ParseContext *pc = s->priv_data;
291 av_freep(&pc->buffer);
294 int ff_mpeg4video_split(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
299 for (i = 0; i < buf_size; i++) {
300 state = state << 8 | buf[i];
301 if (state == 0x1B3 || state == 0x1B6)