02-23-2016 10:54 AM
03-22-2016 09:13 AM
ffmpeg.exe -i my_video_file.mp4 -c:v copy -an my_video_file_SILENT.mp4
ffmpeg.exe -i my_video_file_SILENT.mp4 -i my_ambisonic_audio.wav -c:v copy -c:a libvorbis -q:a 10 my_ambisonic_video.mkv
03-23-2016 01:20 AM
03-24-2016 11:16 AM
03-24-2016 12:55 PM
03-25-2016 09:16 AM
03-26-2016 02:56 PM
03-27-2016 03:41 AM
PeterStirling said:
Non-spatialized audio is not currently implemented. What you can do as a work around is encode it into the ambisonics, this has the added benefit that it will be positioned in the world instead of being locked to the head. The way to do this is to convert your L/R stereo into mid-side format, which is essentially a 1D ambisonic.
To convert L/R to mid-side (in Audacity)
1. Open the stereo track and reduce gain by 6dB [ Effect > Amplify > -6 ]
2. Split the stereo into two mono tracks [click black triangle and select "split stereo to mono"]
3. Mix together into a new mono track. [Track > Mix and Render to New Track]
4. Select right channel (track 2) and invert the phase [ Effect > Invert ]
5. Select tracks 1 and 2 and mix together into a new track again (this is the "side" track)
Tracks 3 and 4 are a mid-side representation of the stereo recording.
6. Select "mid" track (3) and reduce gain by 3dB [ Effect > Amplify > -3 ] This is to match the ambisonic spec that the W channel is 3dB quieter than other channels.
Mix the "mid" track in with your ambisonic W channel.
Mix the "side" track in with your ambisonic Y channel.
03-28-2016 06:56 AM
5.1 audio sounds fine and plays well, but the transitions from one surround to another sounds strange. here is a link with an Ambisonic file decoded to 5.1 (It´s a audio that complete a 360 cycle in about 10 seconds), and some video files, one has ambisonic sound and the others 5.1.
tumbleandyaw said:
Hello Peter,
M/S conversion works, but sums to mono at 90 and 270º. Thanks for the tip.
FOA ogg vorbis with either H264 or VP8 sounds great !.
However, 5.1 audio does not work on my end. All kinds of dropouts and weirdness happening (with H264) or "file cannot be played" (with VP8 video) . Is this just me or is it a known issue?
Can you share the specific codec settings for 5.1? I have it set for Ogg Vorbis pass thru.
Happy Easter!
03-28-2016 12:11 PM
Sassota said:
5.1 audio sounds fine and plays well, but the transitions from one surround to another sounds strange. here is a link with an Ambisonic file decoded to 5.1 (It´s a audio that complete a 360 cycle in about 10 seconds), and some video files, one has ambisonic sound and the others 5.1.
https://www.dropbox.com/s/hrnyq0zvazd3yde/balltestvrplayer.zip?dl=0
03-28-2016 01:26 PM