Problem solved. Here's the YouTube version of one of the most downloaded file from Ambisonia, AJH_eigtht_positions.amb
https://youtu.be/eY9DMn8pgGA Thanks to Albert, Dillon, Bruce, and Marc for suggestions. Dillon diagnosed the problem, but it took a while to discover that the fix had to be applied farther upstream in my processing chain. TL:DR: use a plain old WAV_PCM file for the audio input to FFMPEG, not a WAVE-EX file. I am using the remix effect in SOX to convert from AMB format to ACN/SN3D -- "remix -m 1 3v0.7071 4v0.7071 2v0.7071". When sox writes out a 4-channel file it defaults to WAVE-FORMAT-EXTENSIBLE (which is correct according to the MS standards) with the channel mask set to "quad". I don't see anyway to change that to 4.0. Here's the problem .... when writing a video file, FFMPEG appears to use the channel_mask from the audio file even if a different channel_mask is specified on the command line. So even when I specified "-channel_layout 4.0", the resulting MOV file still had the channel layout set to "quad", which was then rejected by YouTube. The workaround is to use the option "-t wavpcm" to force SOX produce a plain old WAVPCM file. (note that use of WAVPCM for more then 2 channels is undocumented). As a belt-and-suspenders measure, I added "-guess_layout_max 0" to the input in FFMPEG. I wrote a Python script that automates the whole process from AMB to MOV with spatial metadata. You can find it here: https://bitbucket.org/ambidecodertoolbox/amb2yt/src/master/amb2yt.py -- Aaron Heller (hel...@ai.sri.com) Menlo Park, CA US > On Tue, Apr 26, 2016 at 5:17 PM Dillon Cower <dco...@google.com> wrote: > > > Hi Aaron, > > > > Currently the channel layout for upload to YouTube must be 4.0 or > > unspecified <https://support.google.com/youtube/answer/6395969?hl=en>; > > e.g., with ffmpeg, specify "-channel_layout 4.0". We're working on > > improving things regarding other channel layouts. Apologies for the > > confusion in the meantime! > > > > Dillon > > > > On Mon, Apr 25, 2016 at 2:43 PM Bruce Wiggins <bruce.wigg...@gmail.com> > > wrote: > > > > > I've documented the workflow and commands that worked for me here: > > > http://www.brucewiggins.co.uk/?p=666 > > > > > > cheers > > > > > > Bruce > > > > > > On Mon, Apr 25, 2016 at 10:15 PM Albert Leusink < alb...@tumbleandyaw.com > > > > > > wrote: > > > > > > > Aaron Heller <heller@...> writes: > > > > > > > > > > > > > > Is there some trick to uploading these files? The files I make > > upload, > > > > but > > > > > then fail during processing. > > > > > > > > > > > > > > > > > Hi Aaron, > > > > > > > > Try this, start with an MP4 video file and the 4-channel .wav ACN audio > > > > file. Maybe the issue is that you are trying to loop a still image? > > > Also, I > > > > did not specify quad layout, I just attached the 4-ch .wav. > > > > > > > > > > > > -i YT_Videofile.mp4 -i YT_ACN_audiofile.wav -map 0:0 -map 1:0 -c:a > > copy > > > > -async 1 -c:v copy -aspect 1920:960 -pix_fmt yuv420p -threads 8 > > -metadata > > > > creation_time=now -sn -y YoutubeFinal.mov > > > > > > > > It takes about 4 hours for the spatial audio (with the rotation) to > > fully > > > > process after you upload it (sometimes longer), but you should be able > > to > > > > hear the ACN rendered to stereo pretty soon after you upload. > > > > > > > > Hope that helps, > > > > > > > > Albert -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20160507/1b722373/attachment.html> _______________________________________________ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
