Music Media Helper (Tools for Multichannel Audio & Music Videos)

[HomerJAU]

I wanted to express that the objects will not longer be available as such (sound content and metadata) after the encoding back to Dolby Atmos, because the decoded interleaved WAV files would not have that metadata. Of course, all Atmos sound content (Atmos bed channels + Objects) will be in the corresponding channels.

So, a different Dolby Atmos file (with different channels/objects) will result after the decoding/encoding process. But it will sound the same, with the same content in the same channels/speakers.

Am I right?

That's correct if the encode/decode uses the same channel layout as your speaker layout. Play the reencoded file on a system with different speaker layout and it may sound a little different as the objects are now 'hard encoded' to the channel layout specified in the decode/encode process.

 

[alek2702]

That's correct if the encode/decode uses the same channel layout as your speaker layout. Play the reencoded file on a system with different speaker layout and it may sound a little different as the objects are now 'hard encoded' to the channel layout specified in the decode/encode process.

Interesting! So the 16 objects in the original e-ac3's would've been mixed down to 5.1 differently than 16 hard-coded channels in the re-encoded files would?

 

[RvdW]

Works fine now!

 

[AYanguas]

Interesting! So the 16 objects in the original e-ac3's would've been mixed down to 5.1 differently than 16 hard-coded channels in the re-encoded files would?

Yes. Make sense.

When the decode goes to 5.1, you get the whole content but only in 6 channels. The bed channels and objects are "downmixed" to 5.1, the same way an AVR processor would do. Or perhaps the processor would just play the 5.1 substream that form part of the Atmos file (for TrueHD, and for e-ac3 could be different, I'm not sure).

That WAV 5.1 file will be indistinguishable from a file mixed only for 5.1 (no Atmos). Then, when encoding to Atmos, only 6 channels will appear like bed channels Atmos format 5.1.
The height content, "downmixed" to floor 5.1, will not appear again with re-encoded to Atmos. The re-encode will just preserve the channels as they are in WAV, without doing any upmixing like DSU.

The mch WAV file may have more than 6 channels, either when decoding or converting after the WAV file. For instance, with 8 channels 7.1 it could be interested to move the side surrounds to rear surrounds from the 5.1, leaving the sides silent. There are other menu options in MMH to do that kind of conversions.

This is the way some Quad 4.0 mixes are encoded into Atmos redirecting the rears to the Atmos Rears instead of the Sides. That could provide a more Square Quad in some rooms.
The Suzanne Ciani -Live Quadraphonic is done in this way, first time appearing in Tidal Atmos, when there is Atmos support but no 5.1 support.
@kamranv used other workflow process, using 4 objects for the room corners, but the result would be similar. See Atmos release of Suzanne Ciani - LIVE Quadraphonic

 

[alek2702]

Yes. Make sense.

When the decode goes to 5.1, you get the whole content but only in 6 channels. The bed channels and objects are "downmixed" to 5.1, the same way an AVR processor would do. Or perhaps the processor would just play the 5.1 substream that form part of the Atmos file (for TrueHD, and for e-ac3 could be different, I'm not sure).

That WAV 5.1 file will be indistinguishable from a file mixed only for 5.1 (no Atmos). Then, when encoding to Atmos, only 6 channels will appear like bed channels Atmos format 5.1.
The height content, "downmixed" to floor 5.1, will not appear again with re-encoded to Atmos. The re-encode will just preserve the channels as they are in WAV, without doing any upmixing like DSU.

The mch WAV file may have more than 6 channels, either when decoding or converting after the WAV file. For instance, with 8 channels 7.1 it could be interested to move the side surrounds to rear surrounds from the 5.1, leaving the sides silent. There are other menu options in MMH to do that kind of conversions.

This is the way some Quad 4.0 mixes are encoded into Atmos redirecting the rears to the Atmos Rears instead of the Sides. That could provide a more Square Quad in some rooms.
The Suzanne Ciani -Live Quadraphonic is done in this way, first time appearing in Tidal Atmos, when there is Atmos support but no 5.1 support.
@kamranv used other workflow process, using 4 objects for the room corners, but the result would be similar. See Atmos release of Suzanne Ciani - LIVE Quadraphonic

Sorry if I wasn't didn't explain it best in my earlier post, but what I actually meant is whether these two workflows produce different sounding results:

15 object eac-3 -> AVR -> 5.1 speaker layout (or anything below 9.1.6)

15 object eac-3 -> 9.1.6 VAW -> 9.1.6 channel based Atmos -> AVR -> 5.1 speaker layout (or anything below 9.1.6)


If I understood @HomerJAU correctly, they might sound different so just wondering where the change happen.

Either way, I'm guessing the latter is the closest we can get to retaining all the source spatial information, while being able to do some adjustmnets (volume change, trimming gaps, etc).

 

[AYanguas]

Interesting! So the 16 objects in the original e-ac3's would've been mixed down to 5.1 differently than 16 hard-coded channels in the re-encoded files would?

Sorry,

re-reading your post, I don't know if I understood you correctly in my previous answer.

If you decode and the reencode to exactly the same channels/speakers configuration you have in your room, the result will sound the same although the final Atmos will have different Objects structure. Some Objects could have been moved/downmixed to bed channel, etc.

The thing is that when encoding back to Atmos, just the input WAV file channels are "transferred" to those "fixed" Atmos Channels.

 

[AYanguas]

Sorry if I wasn't didn't explain it best in my earlier post, but what I actually meant is whether these two workflows produce different sounding results:

15 object eac-3 -> AVR -> 5.1 speaker layout (or anything below 9.1.6)

15 object eac-3 -> 9.1.6 VAW -> 9.1.6 channel based Atmos -> AVR -> 5.1 speaker layout (or anything below 9.1.6)


If I understood @HomerJAU correctly, they might sound different so just wondering where the change happen.

Either way, I'm guessing the latter is the closest we can get to retaining all the source spatial information, while being able to do some adjustmnets (volume change, trimming gaps, etc).

Upps, I didn't see this. We are writing at the same time.

My guess is that, even if the final Atmos file have a different objects structure, it will sound the same if you decode/encode to the same layout you have in your room speakers.

But if you decode to a WAV file different than your room, the final result could eventually sound different (or not), considering the AVR decoder has to deal with a different objects structure. Well, I hope I have expressed it right.

 

[AYanguas]

Either way, I'm guessing the latter is the closest we can get to retaining all the source spatial information, while being able to do some adjustmnets (volume change, trimming gaps, etc).

This seem to be interesting, decoding/encoding to max layout channels, even if you have less speakers. For when trying to fine tune individual objects/channels either for volume or by merging/copying the content to other channels.

For instance, with the last Riverside Atmos album, the Mariusz Duda main vocals is mostly isolated in the Center channel, and the voice is the only content in Center channel.
I did copy/merge the Center content to the sides channels, testing with different volume levels. I reencoded the new WAV file and did get a more satisfying immersive vocals to my taste.

 

[HomerJAU]

Music Media Helper 6.4.8 Released:

Version 6.4.8 (March 16 2023)
-------------
Fixes:
Atmos Helper tool: MediaInfo bug causes Atmos Helper to fail to load certain multichannel wav files - fixed


For some unknown reason MediaInfo does not find the Duration of certain wav files. This caused MMH Atmos Helper to fail on loading these files . MMH now ignores the duration if this occurs.

 

[MC_Freak]

Wow,.. thanks a lot for this!

 

[MC_Freak]

Thanks again for these awesome tools!
So far it works great for FLAC rips from my Blu-ray collection. I used several tools to do this before. It saves me a lot of time.

Now I want to encode the Atmos mix of my favorite album to Dolby Digital Plus in m4a so I can play it on my phone.
I've ripped the album to mkv with MakeMKV. Decoded the Atmos track to multichannel interleaved WAV files (9.1.6) with the MMH Atmos Helper.
And encoded the WAV files to Dolby Digital Plus (1024 kb/s).

MediaInfo shows this:

Audio
ID                             : 1
Format                         : E-AC-3 JOC
Format/Info                    : Enhanced AC-3 with Joint Object Coding
Commercial name                : Dolby Digital Plus with Dolby Atmos
Codec ID                       : ec-3
Duration                       : 4 min 31 s
Bit rate mode                  : Constant
Bit rate                       : 1 024 kb/s
Channel(s)                     : 6 channels
Channel layout                 : L R C LFE Ls Rs
Sampling rate                  : 48.0 kHz
Frame rate                     : 31.250 FPS (1536 SPF)
Compression mode               : Lossy
Stream size                    : 33.1 MiB (98%)
Service kind                   : Complete Main
Default                        : Yes
Alternate group                : 1
Complexity index               : Not present / 16
Number of dynamic objects      : 15
Bed channel count              : 1 channel
Bed channel configuration      : LFE

Everything looks oké except for the Complexity index: Not present / 16
Is that normal, a bug, or did I something wrong?

 

[HomerJAU]

If you want to encode to Atmos correctly you should first run the Atmos decoder on the MKV file to create a 5.1.4 or 7.1.4 interleaved wav, then reencode that to DD+ Atmos.

But if you are not playing back Atmos on a 5.1.4 or 7.1 4 system (just on headphones) you could probably just encode as you have done above as the ‘Extract MKV to FLAC or WAV’ will extract all the music info to a 7.1 file fir encoding to 5.1 or 7.1 Atmos. You could take a listen and compare the two versions, I would think they would sound similar. If so, take the easiest route.

 

[MC_Freak]

I've edited the post above. I now used the Atmos decoder to decode the Atmos track to multichannel interleaved WAV files (9.1.6).
The complexity index still says "Not present / 16". Normally it should say 16.

A lot of phones now support Dolby Atmos and convert it to virtual surround when you listen it with headphones.
It works amazingly good on my iPhone, I can really hear the height channels.

Anyway,.. time to go to bed for me. It's 02:24 over here.

 

[HomerJAU]

A lot of phones now support Dolby Atmos and convert it to virtual surround when you listen it with headphones

I bought a new Ford Everest (next Gen which in not sold everywhere, but similar to the new Ford Ranger next Gen). The 10 speaker sound system plays in surround from my iPhone playing Apple Atmos albums. I have not tried playing my own Atmos files. How are you playing yours?

 

[MC_Freak]

Currently via File Explorer. File explorer can't play a whole directory or selected files, just one by one. + just in specific formats (in mp4 & m4a).
Sadly I haven't found an app that supports it yet. I've requested the option for a few apps. VLC should support it but it's very buggy on my phone.

Edit: But I'm talking about Spatial Audio... Playing them in your car should be possible with nPlayer. In nPlayer you can choose which codecs you want to use. Via the system codecs it should support surround sound output.
nPlayer plays anything that I throw at it and you can browse directories for content. You don't need iTunes anymore.

 

[mandrix]

Please excuse the slightly off topic post, but since Garry brought up the Everest being similar to the Ranger... I don't know how big the new Ford Ranger's are. But I drive a 1996 Ranger we bought new since I gave up my Z28 "street rod".
Anyway I can't imagine cramming 10 speakers into it. I believe it has speakers in the doors and in the corners behind the seats close to the floor. I don't know where else you could put any. Would love to try though! lol. Getting in a large enough head unit/amp might be a problem.

carry on.

Garry does sox not find length of wav files? Been a while, I might have wrong tool.

 

[MC_Freak]

Hi HomerJAU,
I play the Atmos tracks now with FE File Explorer Pro (as suggested here on the forum). It plays surround music, including Atmos, in Apple Spatial Audio on iPhone/iPad with AirPods Pro, AirPods Max, AirPods (3rd generation), or Beats Fit Pro with Spatial Audio turned on. It sadly still does not support surround tracks in videos yet.

I ran into a bug: When I play downloaded Atmos tracks (DD+ M4A) the Headphone Settings display "Dolby Atmos", but when I play the files encoded with MMH Atmos Helper, it displays "Multichannel". It still plays in Apple Spatial Audio (the icon also displays soundwaves above the head).
Edit: I've narrowed it down to the muxing part. When I mux the ec3 files (from the Encoded folder) with MP4Box to m4a and play them on my iPhone they display "Dolby Atmos". MediaInfo now also reports "Complexity index: 16" like it should, instead of "Complexity index: Not present / 16" (see a few posts above).

+ About a good app to use for playing Dolby Atmos tracks in your car: nPlayer supports streaming of Dolby Digital (AC-3), Dolby Digital Plus (E-AC-3) and DTS via HDMI Pass-through, Airplay Pass-through and Chromecast Pass-through.

 

[HomerJAU]

I bought the FE File Explorer but couldn’t find a way to play files from a connected drive. It wants to connect via a network. Maybe I should try latest version but my aim was to play my files when in my car.

Can you tell me more about your MMH Atmos Helper encoded files? I noticed a previous Mediainfo report shows you used 1024kbps encode, maybe Apple only supports DD+ Atmos at 768? Can you try an encode using 768 and confirm results please?

 

[HomerJAU]

Edit: I've narrowed it down to the muxing part. When I mux the ec3 files (from the Encoded folder) with MP4Box to m4a and play them on my iPhone they display "Dolby Atmos". MediaInfo now also reports "Complexity index: 16" like it should, instead of "Complexity index: Not present / 16" (see a few posts above).

MMH Atmos Helper will create M4A wont it?

 

[MC_Freak]

MMH Atmos Helper will create M4A wont it?

Yes, but those give the error. I also tried an encode using 768, it makes no difference. When I mux them with MP4Box, the error is gone.