// // Created by xu fulong on 2022/5/13. // #include #ifdef __ANDROID__ #include #define LOGE(FORMAT, ...) __android_log_print(ANDROID_LOG_ERROR, "CutVideo", FORMAT, ##__VA_ARGS__) #else #include #define LOGE(FORMAT, ...) printf(FORMAT, ##__VA_ARGS__) #endif int CutVideo::open_output_file(AVFormatContext *ifmt_ctx, const char *filename) { int ret; avformat_alloc_output_context2(&ofmt_ctx, nullptr, nullptr, filename); if (!ofmt_ctx) { LOGE("Could not create output context\n"); return AVERROR_UNKNOWN; } dts_start_offset = new int64_t [ifmt_ctx->nb_streams]; memset(dts_start_offset, -1, sizeof(int64_t) * ifmt_ctx->nb_streams); pts_start_offset = new int64_t [ifmt_ctx->nb_streams]; memset(pts_start_offset, -1, sizeof(int64_t) * ifmt_ctx->nb_streams); for (int i = 0; i < ifmt_ctx->nb_streams; i++) { AVStream* in_stream = ifmt_ctx->streams[i]; AVCodecParameters* codecpar = in_stream->codecpar; AVCodec* dec = avcodec_find_decoder(codecpar->codec_id); AVStream* out_stream = avformat_new_stream(ofmt_ctx, dec); if (!out_stream) { LOGE("Failed allocating output stream\n"); ret = AVERROR_UNKNOWN; return ret; } avcodec_parameters_copy(out_stream->codecpar, codecpar); } av_dump_format(ofmt_ctx, 0, filename, 1); if (!(ofmt_ctx->oformat->flags & AVFMT_NOFILE)) { ret = avio_open(&ofmt_ctx->pb, filename, AVIO_FLAG_WRITE); if (ret < 0) { LOGE("Could not open output file %s\n", filename); return ret; } } /* init muxer, write output file header */ ret = avformat_write_header(ofmt_ctx, nullptr); if (ret < 0) { LOGE("Error occurred when opening output file\n"); return ret; } return 0; } void CutVideo:: setParam(int64_t start_time, int64_t duration) { m_startTime = start_time; m_duration = duration; } AVPacket* CutVideo::copy_packet(AVFormatContext *ifmt_ctx, AVPacket *packet) { auto* pkt = (AVPacket*)av_malloc(sizeof(AVPacket)); av_new_packet(pkt, 0); if (0 == av_packet_ref(pkt, packet)) { AVStream* in_stream = ifmt_ctx->streams[pkt->stream_index]; AVStream* out_stream = ofmt_ctx->streams[pkt->stream_index]; if (pts_start_offset[pkt->stream_index] == -1) { pts_start_offset[pkt->stream_index] = pkt->pts; dts_start_offset[pkt->stream_index] = pkt->dts; } // convert pts and dts pkt->pts = av_rescale_q_rnd(pkt->pts, in_stream->time_base, out_stream->time_base, static_cast(AV_ROUND_NEAR_INF | AV_ROUND_PASS_MINMAX)); pkt->dts = av_rescale_q_rnd(pkt->dts, in_stream->time_base, out_stream->time_base, static_cast(AV_ROUND_NEAR_INF | AV_ROUND_PASS_MINMAX)); pkt->duration = av_rescale_q(pkt->duration, in_stream->time_base, out_stream->time_base); return pkt; } return nullptr; } int CutVideo::write_internal(AVFormatContext *ifmt_ctx, AVPacket *packet) { int ret; AVPacket *pkt = copy_packet(ifmt_ctx, packet); if (pkt == nullptr) { LOGE("packet is NULL\n"); return -1; } pkt->pts = pkt->pts - pts_start_offset[pkt->stream_index]; pkt->dts = pkt->dts - dts_start_offset[pkt->stream_index]; // LOGE("pts=%ld, dts=%ld, stream_index=%d", pkt->pts, pkt->dts, pkt->stream_index); // write packet into file //TODO:when pts < dts, it occurs error. // Therefore, wo need to cache packet queue, and ascend sort by dts if ((ret = av_interleaved_write_frame(ofmt_ctx, pkt)) < 0) { LOGE("Error to mux packet, stream_index=%d, pts=%ld, dts=%ld\n", pkt->stream_index, pkt->pts, pkt->dts); } av_packet_unref(pkt); return ret; } void CutVideo::write_output_file(AVFormatContext *ifmt_ctx, AVPacket *packet) { int64_t timestamp = packet->pts * av_q2d(ifmt_ctx->streams[packet->stream_index]->time_base); if (timestamp >= m_startTime && timestamp < m_startTime + m_duration) { write_internal(ifmt_ctx, packet); } } void CutVideo::close_output_file() { if (!ofmt_ctx) return; av_write_trailer(ofmt_ctx); if (!(ofmt_ctx->oformat->flags & AVFMT_NOFILE)) { avio_close(ofmt_ctx->pb); } avformat_free_context(ofmt_ctx); delete pts_start_offset; delete dts_start_offset; }