I'm new to posting here, but I've been playing with audio/video encoding since around 2011.
Since that time I've had an interest in Dolby Digital Plus (DD+) or E-AC3. I am a pretty big enthusiast with surround sound, and enjoy keeping the best possible quality while also remaining efficient on file sizes, etc. I typically use MKV and encode with X264/265 and E-AC3 audio.
Since EAC3 encoding isn't all that supported or that popular in the open source community, I purchased a program called Dolby Media Encoder years ago as part of a larger package of tools. It allows you to take a source like TrueHD, or DTS-MA, extract the (up to) 8 channels of audio in to an individual .wav file for each channel and then re-encode to DD+/EAC3.
It took me a couple of years to go down the line with the authors of different programs and software to deal with 7.1 channel EAC3 audio. Most implementations handle 5.1 channel audio just fine but have no support for the extension channels that EAC3 supports. Basically EAC3 has the 5.1 channel AC3 core, and then has 4 extra channels that contain 4 surround channels that replace the two surround channels in the EAC3/AC3 core. I'm sure no one needs a lesson on that, as you can find the info anywhere. It was quite sometime before I could successfully mux it into a container of any kind before MkvToolnix/MkvMerge added support more recently.
So far the only program that can play these files correctly is Windows Media player. It can successfully play 7.1 channel PCM output or the EAC3 7.1 channel bitstream. When outputting to a hardware receiver, the audio codec is displayed and the channels light up individually, and I've verified the sound.
Recently, I reported an issue with VLC playing these files, and the most recent nightly builds have shown some progress as the authors have been very attentive. The issue with VLC is that it also identifies the files as 5.1 channels. The audio would stutter on 7.1 channel files and they wouldn't play normally. Since then, they've solved the stuttering audio problem when more channels are present, but it's only outputting the 5.1 core AC3. Still a work in progress.
Since I use Kodi for my media library, here I am posting...
I started with a standard 7.1 DTS-MA file. I can output either the 7.1 channel PCM by disabling audio pass-through or else the 7.1 channel bitstream and all works perfectly either way. I confirmed the hardware receiver output.
Next I went to my 7.1 channel EAC3 file. I can output PCM, but Kodi see's this a 5.1 channel file, and the rear channels are dead. Next I tried the audio passthrough turned on, and the bitstream makes it to the hardware receiver, but there is no sound, and the receiver keeps switching between 6 channel (5.1) audio and 8 (7.1) channel audio with the display flickering.
I repeated this test with EAC3 5.1 audio, and both PCM and EAC3/DD+ Pass-through work perfectly.
So again, I think I've hit a limitation that is present in software that is not expecting to have the extension channels in EAC3.
My conclusion is that since I am using actual Dolby branded encoding software, Windows Media Player can play these files correctly, and the hardware receiver is Dolby certified, that the problem lies with the implementation in Kodi. I think that DD+ is rare (especially 7.1 channel) since HD-DVD went away, and free EAC3 encoders aren't really around.
I'm hoping that I can help do my part to get the DD+ implementations corrected in software so that when EAC3 encoders are available that a lot of this work will be completed in advance while also helping myself to have an efficient library.
When using x265 with EAC3, a movie with 8 channel surround can be be around 2GB with great quality whereas the version with TrueHD or DTS-MA is 6-7GB just trying to preserve the 7.1 channel sound. Basically EAC3 is the perfect companion to HEVC/X265.
I am more than willing to help providing samples, testing and participating in any effort to correct this. If anyone thinks I'm wrong in my observation or wishes to help me confirm the problem, I'm more than willing to admit I've done something wrong.
Please let me know what you all think.
Since that time I've had an interest in Dolby Digital Plus (DD+) or E-AC3. I am a pretty big enthusiast with surround sound, and enjoy keeping the best possible quality while also remaining efficient on file sizes, etc. I typically use MKV and encode with X264/265 and E-AC3 audio.
Since EAC3 encoding isn't all that supported or that popular in the open source community, I purchased a program called Dolby Media Encoder years ago as part of a larger package of tools. It allows you to take a source like TrueHD, or DTS-MA, extract the (up to) 8 channels of audio in to an individual .wav file for each channel and then re-encode to DD+/EAC3.
It took me a couple of years to go down the line with the authors of different programs and software to deal with 7.1 channel EAC3 audio. Most implementations handle 5.1 channel audio just fine but have no support for the extension channels that EAC3 supports. Basically EAC3 has the 5.1 channel AC3 core, and then has 4 extra channels that contain 4 surround channels that replace the two surround channels in the EAC3/AC3 core. I'm sure no one needs a lesson on that, as you can find the info anywhere. It was quite sometime before I could successfully mux it into a container of any kind before MkvToolnix/MkvMerge added support more recently.
So far the only program that can play these files correctly is Windows Media player. It can successfully play 7.1 channel PCM output or the EAC3 7.1 channel bitstream. When outputting to a hardware receiver, the audio codec is displayed and the channels light up individually, and I've verified the sound.
Recently, I reported an issue with VLC playing these files, and the most recent nightly builds have shown some progress as the authors have been very attentive. The issue with VLC is that it also identifies the files as 5.1 channels. The audio would stutter on 7.1 channel files and they wouldn't play normally. Since then, they've solved the stuttering audio problem when more channels are present, but it's only outputting the 5.1 core AC3. Still a work in progress.
Since I use Kodi for my media library, here I am posting...
I started with a standard 7.1 DTS-MA file. I can output either the 7.1 channel PCM by disabling audio pass-through or else the 7.1 channel bitstream and all works perfectly either way. I confirmed the hardware receiver output.
Next I went to my 7.1 channel EAC3 file. I can output PCM, but Kodi see's this a 5.1 channel file, and the rear channels are dead. Next I tried the audio passthrough turned on, and the bitstream makes it to the hardware receiver, but there is no sound, and the receiver keeps switching between 6 channel (5.1) audio and 8 (7.1) channel audio with the display flickering.
I repeated this test with EAC3 5.1 audio, and both PCM and EAC3/DD+ Pass-through work perfectly.
So again, I think I've hit a limitation that is present in software that is not expecting to have the extension channels in EAC3.
My conclusion is that since I am using actual Dolby branded encoding software, Windows Media Player can play these files correctly, and the hardware receiver is Dolby certified, that the problem lies with the implementation in Kodi. I think that DD+ is rare (especially 7.1 channel) since HD-DVD went away, and free EAC3 encoders aren't really around.
I'm hoping that I can help do my part to get the DD+ implementations corrected in software so that when EAC3 encoders are available that a lot of this work will be completed in advance while also helping myself to have an efficient library.
When using x265 with EAC3, a movie with 8 channel surround can be be around 2GB with great quality whereas the version with TrueHD or DTS-MA is 6-7GB just trying to preserve the 7.1 channel sound. Basically EAC3 is the perfect companion to HEVC/X265.
I am more than willing to help providing samples, testing and participating in any effort to correct this. If anyone thinks I'm wrong in my observation or wishes to help me confirm the problem, I'm more than willing to admit I've done something wrong.
Please let me know what you all think.