--audio-width problem with transcode-video on CentOS

[nobitataj]

Hi, recently I encountered a problem with transcoding video on CentOS 7. The input file contains audio track in Dolby format. I wanted the output to have only stereo audio AAC format, so I added --audio-width main=stereo into the command. The output is as expected when I tested in my local MacOS computer. However the output file when I run the command on CentOS still have audio track with 6 channels, when I inspect the output file with ffprobe, it comes like this: { "index": 1, "codec_name": "aac", "codec_long_name": "AAC (Advanced Audio Coding)", "profile": "LC", "codec_type": "audio", "codec_time_base": "1/48000", "codec_tag_string": "mp4a", "codec_tag": "0x6134706d", "sample_fmt": "fltp", "sample_rate": "48000", "channels": 6, "bits_per_sample": 0, "r_frame_rate": "0/0", "avg_frame_rate": "0/0", "time_base": "1/48000", "start_pts": -440, "start_time": "-0.009167", "duration_ts": 20020800, "duration": "417.100000", "bit_rate": "384516", "max_bit_rate": "384516", "nb_frames": "19552", "disposition": { "default": 1, "dub": 0, "original": 0, "comment": 0, "lyrics": 0, "karaoke": 0, "forced": 0, "hearing_impaired": 0, "visual_impaired": 0, "clean_effects": 0, "attached_pic": 0, "timed_thumbnails": 0 }, "tags": { "creation_time": "2018-08-28T04:42:02.000000Z", "language": "eng", "handler_name": "Surround" } } ] Any ideas where I could have been using it incorrectly? Thanks in advance P.S: I use latest HandBrake version, following this guide: https://handbrake.fr/docs/en/latest/developer/install-dependencies-centos.html

[nobitataj]

Tested on Ubuntu, seems that this problem only happens on Cent

[lisamelton]

@nobitataj Interesting. It seems the audio mixdown defaults are different on CentOS than any other platform.

You could try forcing the audio mixdown on CentOS by adding --handbrake-option mixdown=dpl2 to your command line. The dpl2 indicates that you want a stereo mix in Dolby Prologic II format.

Let me know if that works. And thanks for opening this issue!

[nobitataj]

@donmelton perfect { "index": 1, "codec_name": "aac", "codec_long_name": "AAC (Advanced Audio Coding)", "profile": "LC", "codec_type": "audio", "codec_time_base": "1/48000", "codec_tag_string": "mp4a", "codec_tag": "0x6134706d", "sample_fmt": "fltp", "sample_rate": "48000", "channels": 2, "channel_layout": "stereo", "bits_per_sample": 0, "r_frame_rate": "0/0", "avg_frame_rate": "0/0", "time_base": "1/48000", "start_pts": 0, "start_time": "0.000000", "duration_ts": 135420912, "duration": "2821.269000", "bit_rate": "158904", "max_bit_rate": "158904", "nb_frames": "132248", "disposition": { "default": 1, "dub": 0, "original": 0, "comment": 0, "lyrics": 0, "karaoke": 0, "forced": 0, "hearing_impaired": 0, "visual_impaired": 0, "clean_effects": 0, "attached_pic": 0, "timed_thumbnails": 0 }, "tags": { "creation_time": "2018-08-29T01:50:23.000000Z", "language": "eng", "handler_name": "Stereo" } }, { "index": 2, "codec_name": "ac3", "codec_long_name": "ATSC A/52A (AC-3)", "codec_type": "audio", "codec_time_base": "1/48000", "codec_tag_string": "ac-3", "codec_tag": "0x332d6361", "sample_fmt": "fltp", "sample_rate": "48000", "channels": 2, "channel_layout": "stereo", "bits_per_sample": 0, "dmix_mode": "-1", "ltrt_cmixlev": "-1.000000", "ltrt_surmixlev": "-1.000000", "loro_cmixlev": "-1.000000", "loro_surmixlev": "-1.000000", "r_frame_rate": "0/0", "avg_frame_rate": "0/0", "time_base": "1/48000", "start_pts": 0, "start_time": "0.000000", "duration_ts": 135421152, "duration": "2821.274000", "bit_rate": "224000", "nb_frames": "88165", "disposition": { "default": 0, "dub": 0, "original": 0, "comment": 0, "lyrics": 0, "karaoke": 0, "forced": 0, "hearing_impaired": 0, "visual_impaired": 0, "clean_effects": 0, "attached_pic": 0, "timed_thumbnails": 0 }, "tags": { "creation_time": "2018-08-29T01:50:23.000000Z", "language": "eng", "handler_name": "Stereo" }, "side_data_list": [ { "side_data_type": "Audio Service Type" } ] }

Tested on Mac and Cent, let me try on Ubuntu

[nobitataj]

Ubuntu verified working, thanks a lot @donmelton

[lisamelton]

@nobitataj Excellent! I'll close this now but feel free to comment here or open other useful issues like this one.