lock_guard<mutex> lock(file_audio_encoder_mutex);
AVCodecParametersWithDeleter audio_codecpar = file_audio_encoder->get_codec_parameters();
file_mux.reset(new Mux(avctx, frame_width, frame_height, Mux::CODEC_H264, video_extradata, audio_codecpar.get(), get_color_space(global_flags.ycbcr_rec709_coefficients), Mux::WITH_AUDIO, TIMEBASE,
lock_guard<mutex> lock(file_audio_encoder_mutex);
AVCodecParametersWithDeleter audio_codecpar = file_audio_encoder->get_codec_parameters();
file_mux.reset(new Mux(avctx, frame_width, frame_height, Mux::CODEC_H264, video_extradata, audio_codecpar.get(), get_color_space(global_flags.ycbcr_rec709_coefficients), Mux::WITH_AUDIO, TIMEBASE,