/* * 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 */ /* shared code for simple demux/decode tools */ #include <stdlib.h> #include <string.h> #include "decode_simple.h" #include "libavformat/avformat.h" #include "libavcodec/avcodec.h" #include "libavcodec/packet.h" #include "libavutil/dict.h" #include "libavutil/error.h" #include "libavutil/frame.h" static int decode_read(DecodeContext *dc, int flush) { const int ret_done = flush ? AVERROR_EOF : AVERROR(EAGAIN); int ret = 0; while (ret >= 0 && (dc->max_frames == 0 || dc->decoder->frame_num < dc->max_frames)) { ret = avcodec_receive_frame(dc->decoder, dc->frame); if (ret < 0) { if (ret == AVERROR_EOF) { int err = dc->process_frame(dc, NULL); if (err < 0) return err; } return (ret == ret_done) ? 0 : ret; } ret = dc->process_frame(dc, dc->frame); av_frame_unref(dc->frame); if (ret < 0) return ret; if (dc->max_frames && dc->decoder->frame_num == dc->max_frames) return 1; } return (dc->max_frames == 0 || dc->decoder->frame_num < dc->max_frames) ? 0 : 1; } int ds_run(DecodeContext *dc) { int ret; ret = avcodec_open2(dc->decoder, NULL, &dc->decoder_opts); if (ret < 0) return ret; while (ret >= 0) { ret = av_read_frame(dc->demuxer, dc->pkt); if (ret < 0) break; if (dc->pkt->stream_index != dc->stream->index) { av_packet_unref(dc->pkt); continue; } ret = avcodec_send_packet(dc->decoder, dc->pkt); if (ret < 0) { fprintf(stderr, "Error decoding: %d\n", ret); return ret; } av_packet_unref(dc->pkt); ret = decode_read(dc, 0); if (ret < 0) { fprintf(stderr, "Error decoding: %d\n", ret); return ret; } else if (ret > 0) goto finish; } avcodec_send_packet(dc->decoder, NULL); ret = decode_read(dc, 1); if (ret < 0) { fprintf(stderr, "Error flushing: %d\n", ret); return ret; } finish: return dc->process_frame(dc, NULL); } void ds_free(DecodeContext *dc) { av_dict_free(&dc->decoder_opts); av_frame_free(&dc->frame); av_packet_free(&dc->pkt); avcodec_free_context(&dc->decoder); avformat_close_input(&dc->demuxer); } int ds_open(DecodeContext *dc, const char *url, int stream_idx) { const AVCodec *codec; int ret; memset(dc, 0, sizeof(*dc)); dc->pkt = av_packet_alloc(); dc->frame = av_frame_alloc(); if (!dc->pkt || !dc->frame) { ret = AVERROR(ENOMEM); goto fail; } ret = avformat_open_input(&dc->demuxer, url, NULL, NULL); if (ret < 0) { fprintf(stderr, "Error opening input file: %d\n", ret); return ret; } if (stream_idx < 0 || stream_idx >= dc->demuxer->nb_streams) return AVERROR(EINVAL); dc->stream = dc->demuxer->streams[stream_idx]; codec = avcodec_find_decoder(dc->stream->codecpar->codec_id); if (!codec) return AVERROR_DECODER_NOT_FOUND; dc->decoder = avcodec_alloc_context3(codec); if (!dc->decoder) return AVERROR(ENOMEM); ret = avcodec_parameters_to_context(dc->decoder, dc->stream->codecpar); if (ret < 0) goto fail; return 0; fail: ds_free(dc); return ret; }