/* * Audio and Video frame extraction * Copyright (c) 2003 Fabrice Bellard * Copyright (c) 2003 Michael Niedermayer * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include <stdint.h> #include <string.h> #include "libavutil/avassert.h" #include "libavutil/atomic.h" #include "libavutil/mem.h" #include "internal.h" #include "parser.h" static AVCodecParser *av_first_parser = NULL; AVCodecParser *av_parser_next(const AVCodecParser *p) { if (p) return p->next; else return av_first_parser; } void av_register_codec_parser(AVCodecParser *parser) { do { parser->next = av_first_parser; } while (parser->next != avpriv_atomic_ptr_cas((void * volatile *)&av_first_parser, parser->next, parser)); } AVCodecParserContext *av_parser_init(int codec_id) { AVCodecParserContext *s = NULL; AVCodecParser *parser; int ret; if (codec_id == AV_CODEC_ID_NONE) return NULL; for (parser = av_first_parser; parser; parser = parser->next) { if (parser->codec_ids[0] == codec_id || parser->codec_ids[1] == codec_id || parser->codec_ids[2] == codec_id || parser->codec_ids[3] == codec_id || parser->codec_ids[4] == codec_id) goto found; } return NULL; found: s = av_mallocz(sizeof(AVCodecParserContext)); if (!s) goto err_out; s->parser = parser; s->priv_data = av_mallocz(parser->priv_data_size); if (!s->priv_data) goto err_out; s->fetch_timestamp=1; s->pict_type = AV_PICTURE_TYPE_I; if (parser->parser_init) { ret = parser->parser_init(s); if (ret != 0) goto err_out; } s->key_frame = -1; s->convergence_duration = 0; s->dts_sync_point = INT_MIN; s->dts_ref_dts_delta = INT_MIN; s->pts_dts_delta = INT_MIN; s->format = -1; return s; err_out: if (s) av_freep(&s->priv_data); av_free(s); return NULL; } void ff_fetch_timestamp(AVCodecParserContext *s, int off, int remove, int fuzzy) { int i; if (!fuzzy) { s->dts = s->pts = AV_NOPTS_VALUE; s->pos = -1; s->offset = 0; } for (i = 0; i < AV_PARSER_PTS_NB; i++) { if (s->cur_offset + off >= s->cur_frame_offset[i] && (s->frame_offset < s->cur_frame_offset[i] || (!s->frame_offset && !s->next_frame_offset)) && // first field/frame // check disabled since MPEG-TS does not send complete PES packets /*s->next_frame_offset + off <*/ s->cur_frame_end[i]){ if (!fuzzy || s->cur_frame_dts[i] != AV_NOPTS_VALUE) { s->dts = s->cur_frame_dts[i]; s->pts = s->cur_frame_pts[i]; s->pos = s->cur_frame_pos[i]; s->offset = s->next_frame_offset - s->cur_frame_offset[i]; } if (remove) s->cur_frame_offset[i] = INT64_MAX; if (s->cur_offset + off < s->cur_frame_end[i]) break; } } } int av_parser_parse2(AVCodecParserContext *s, AVCodecContext *avctx, uint8_t **poutbuf, int *poutbuf_size, const uint8_t *buf, int buf_size, int64_t pts, int64_t dts, int64_t pos) { int index, i; uint8_t dummy_buf[AV_INPUT_BUFFER_PADDING_SIZE]; if (!(s->flags & PARSER_FLAG_FETCHED_OFFSET)) { s->next_frame_offset = s->cur_offset = pos; s->flags |= PARSER_FLAG_FETCHED_OFFSET; } if (buf_size == 0) { /* padding is always necessary even if EOF, so we add it here */ memset(dummy_buf, 0, sizeof(dummy_buf)); buf = dummy_buf; } else if (s->cur_offset + buf_size != s->cur_frame_end[s->cur_frame_start_index]) { /* skip remainder packets */ /* add a new packet descriptor */ i = (s->cur_frame_start_index + 1) & (AV_PARSER_PTS_NB - 1); s->cur_frame_start_index = i; s->cur_frame_offset[i] = s->cur_offset; s->cur_frame_end[i] = s->cur_offset + buf_size; s->cur_frame_pts[i] = pts; s->cur_frame_dts[i] = dts; s->cur_frame_pos[i] = pos; } if (s->fetch_timestamp) { s->fetch_timestamp = 0; s->last_pts = s->pts; s->last_dts = s->dts; s->last_pos = s->pos; ff_fetch_timestamp(s, 0, 0, 0); } /* WARNING: the returned index can be negative */ index = s->parser->parser_parse(s, avctx, (const uint8_t **) poutbuf, poutbuf_size, buf, buf_size); av_assert0(index > -0x20000000); // The API does not allow returning AVERROR codes /* update the file pointer */ if (*poutbuf_size) { /* fill the data for the current frame */ s->frame_offset = s->next_frame_offset; /* offset of the next frame */ s->next_frame_offset = s->cur_offset + index; s->fetch_timestamp = 1; } if (index < 0) index = 0; s->cur_offset += index; return index; } int av_parser_change(AVCodecParserContext *s, AVCodecContext *avctx, uint8_t **poutbuf, int *poutbuf_size, const uint8_t *buf, int buf_size, int keyframe) { if (s && s->parser->split) { if (avctx->flags & AV_CODEC_FLAG_GLOBAL_HEADER || avctx->flags2 & AV_CODEC_FLAG2_LOCAL_HEADER) { int i = s->parser->split(avctx, buf, buf_size); buf += i; buf_size -= i; } } /* cast to avoid warning about discarding qualifiers */ *poutbuf = (uint8_t *) buf; *poutbuf_size = buf_size; if (avctx->extradata) { if (keyframe && (avctx->flags2 & AV_CODEC_FLAG2_LOCAL_HEADER)) { int size = buf_size + avctx->extradata_size; *poutbuf_size = size; *poutbuf = av_malloc(size + AV_INPUT_BUFFER_PADDING_SIZE); if (!*poutbuf) return AVERROR(ENOMEM); memcpy(*poutbuf, avctx->extradata, avctx->extradata_size); memcpy(*poutbuf + avctx->extradata_size, buf, buf_size + AV_INPUT_BUFFER_PADDING_SIZE); return 1; } } return 0; } void av_parser_close(AVCodecParserContext *s) { if (s) { if (s->parser->parser_close) s->parser->parser_close(s); av_freep(&s->priv_data); av_free(s); } } int ff_combine_frame(ParseContext *pc, int next, const uint8_t **buf, int *buf_size) { if (pc->overread) { ff_dlog(NULL, "overread %d, state:%X next:%d index:%d o_index:%d\n", pc->overread, pc->state, next, pc->index, pc->overread_index); ff_dlog(NULL, "%X %X %X %X\n", (*buf)[0], (*buf)[1], (*buf)[2], (*buf)[3]); } /* Copy overread bytes from last frame into buffer. */ for (; pc->overread > 0; pc->overread--) pc->buffer[pc->index++] = pc->buffer[pc->overread_index++]; /* flush remaining if EOF */ if (!*buf_size && next == END_NOT_FOUND) next = 0; pc->last_index = pc->index; /* copy into buffer end return */ if (next == END_NOT_FOUND) { void *new_buffer = av_fast_realloc(pc->buffer, &pc->buffer_size, *buf_size + pc->index + AV_INPUT_BUFFER_PADDING_SIZE); if (!new_buffer) { av_log(NULL, AV_LOG_ERROR, "Failed to reallocate parser buffer to %d\n", *buf_size + pc->index + AV_INPUT_BUFFER_PADDING_SIZE); pc->index = 0; return AVERROR(ENOMEM); } pc->buffer = new_buffer; memcpy(&pc->buffer[pc->index], *buf, *buf_size); pc->index += *buf_size; return -1; } *buf_size = pc->overread_index = pc->index + next; /* append to buffer */ if (pc->index) { void *new_buffer = av_fast_realloc(pc->buffer, &pc->buffer_size, next + pc->index + AV_INPUT_BUFFER_PADDING_SIZE); if (!new_buffer) { av_log(NULL, AV_LOG_ERROR, "Failed to reallocate parser buffer to %d\n", next + pc->index + AV_INPUT_BUFFER_PADDING_SIZE); pc->overread_index = pc->index = 0; return AVERROR(ENOMEM); } pc->buffer = new_buffer; if (next > -AV_INPUT_BUFFER_PADDING_SIZE) memcpy(&pc->buffer[pc->index], *buf, next + AV_INPUT_BUFFER_PADDING_SIZE); pc->index = 0; *buf = pc->buffer; } /* store overread bytes */ for (; next < 0; next++) { pc->state = pc->state << 8 | pc->buffer[pc->last_index + next]; pc->state64 = pc->state64 << 8 | pc->buffer[pc->last_index + next]; pc->overread++; } if (pc->overread) { ff_dlog(NULL, "overread %d, state:%X next:%d index:%d o_index:%d\n", pc->overread, pc->state, next, pc->index, pc->overread_index); ff_dlog(NULL, "%X %X %X %X\n", (*buf)[0], (*buf)[1], (*buf)[2], (*buf)[3]); } return 0; } void ff_parse_close(AVCodecParserContext *s) { ParseContext *pc = s->priv_data; av_freep(&pc->buffer); } int ff_mpeg4video_split(AVCodecContext *avctx, const uint8_t *buf, int buf_size) { uint32_t state = -1; const uint8_t *ptr = buf, *end = buf + buf_size; while (ptr < end) { ptr = avpriv_find_start_code(ptr, end, &state); if (state == 0x1B3 || state == 0x1B6) return ptr - 4 - buf; } return 0; }