SakethSathuvalli
commented
2 years ago Hi,
Thanks for trying our decoder! From the description you provided(specifically “1 blank track”) it sounds to us that the 360 audio file that You are using is a purely object audio file with rendering to 7.1.4 setup as default. We can confirm this if it’s possible for You to share the stream with us.
Blank track: For purely object-based audio streams, the object audio renderer comes into picture for generating final output audio data. LFE Channel is not populated by the object rendering path and hence “the blank track”.
CICP:
Coming to the command line option -cicp: the correct value to be used for 5.1 set up is 6 – CICP is an integer value that represents certain standard playback/rendering set ups. For your setup CICP value 6 will work.
We see that this information is missing in our documentation/help/readme message – we will add the missing information at the earliest.
Parameter Files: The parameter files that you are referring to, are not created by the decoder, rather they are inputs from the user to the decoder. The implementations are based on the MPEG-H codec specifications.
For Your use case, if You want to change the playback set-up to a known standard set up, the -cicp: command line option must be used.
If You are looking at binaural rendered audio(headphones), then use -brir: and pass the bitstream with binaural filter coefficients data(bitstream is expected to be compliant MPEG-H specification).
Thanks!
bluewidy
I got a sony 360 reality audio .mp4 file. I want to enjoy this with my stereo headphones and 5.1 channel surround soundbar system at home.
However, a music player that can play MPEG-H 3D format files doesn't seem to exist, so I came to this GitHub. This software converts MHA1 format to PCM format, allowing you to enjoy music. I looked at the CLI commands to use this program.
First off I've done the basics.
ia_mpeghd_testbench.exe -ifile:input.mp4 -ofile:result.wavThe result was a bit odd. I looked at the waveforms of 12 tracks through Audacity, and 1 track was blank. When I analyzed the mp4 file through the media info, it was stated that it was 7.1.4 channel, but the track extracted through the decoder is 7.1.3 channel, so something is wrong.
Anyway, my soundbar supports 5.1 channels, so I did the following:
ia_mpeghd_testbench.exe -ifile:input.mp4 -ofile:result.wav -cicp:5.1However, the number of channels extracted through the decoder is 5 channels, not 5.1 channels. So, I modified the command as follows:
ia_mpeghd_testbench.exe -ifile:input.mp4 -ofile:result.wav -cicp:6This worked. It was extracted with 5.1 channels. However, this also results in a bit weird. I looked at the waveforms of 6 tracks through Audacity, 1 track was blank. Obviously the decoder looks like something is wrong.
and I have another problem. It's about the parameters file. I don't know what the role of the parameter file is. However, I can make predictions like this:
Probably, in the case of 360 audio, the sound image should be positioned differently depending on the audio playback device. A parameter file will be needed to determine the position between the objects that make up the audio in response to these points. For example, the direction in which a sound image should be localized in stereo headphones and a direction in which a sound image should be localized in a 5.1-channel surround speaker system must be different, and 3D spatial information to which an object should be mapped is required differently depending on the playback device. It looks like it's a parameter file that contains that information, right?
So I want to get the parameter file. But I don't know how. Can I extract the parameters file from my own MPEG-H 3D format mp4 container? Or do I have to find another way?