Dolby Vision now possible through MP4 Mux.

[RESET_9999]

Hi, could you please help me how can I get truehd audio file from m2ts, then convert it to lpcm and attach it to mp4 file (created with DVDFab) with mp4box?
Thank you!

audio:

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ffmpeg.exe -i X:\bluray.m2ts -map 0:2 -c:a pcm_s24be -ar 48000 -rf64 auto X:\lpcm.mov

adding audio to a DVDFAB mp4:

dual layer mp4

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mp4box.exe -add X:\dvdfab-dual-layer.mp4#1 -add X:\dvdfab-dual-layer.mp4#2 -add X:\lpcm.mov#audio:lang=en-EN -tmp X:\ -brand mp42isom -ab dby1 -no-iod X:\dolbyvision-remux.mp4

single layer mp4:

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mp4box.exe -add X:\dvdfab-single-layer.mp4#1 -add X:\lpcm.mov#audio:lang=en-EN -tmp X:\ -brand mp42isom -ab dby1 -no-iod X:\dolbyvision-remux.mp4

[superfans124]

idk, I only demux from m2ts. started out using tsMuxer then moved on to ffmpeg. I did Angel Heart, demuxed from M2TS, created dual-layer DV with DTS-HDMA5.1 re-encoded as PCM5.1, result...

crashes within first 5 seconds, couldn't even get a peak at Studio Canal logo...

yeah, angel heart(crash) and life of pets 2(stutter) is a no go, I had to watch them in HDR10.
but I watched more than 40 DV LPCM movies with the X700 without issue. I have almost the same setup you have, I'm surprised that most of your DV remux freeze your player.
x700 ----> Denon AVR ----> C8

this is the cmd-line I used for all my remux:

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ffmpeg.exe -i D:\1.m2ts -map 0:0 -c copy D:\1.hevc -map 0:1 -c copy D:\2.hevc -map 0:2 -c:a pcm_s24be -ar 48000 -rf64 auto D:\lpcm.mov -map 0:6 -c copy -strict -2 D:\fr.mp4

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mp4muxer_64bits.exe --dv-profile 7 --input-file D:\1.hevc --input-file D:\2.hevc --output-file DVremux.mp4

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mp4box.exe -add D:\DVremux.mp4:rate=0 -add D:\lpcm.mov#audio:lang=en-EN -add D:\fr.mp4#audio:lang=fr-FR -add D:\fr.srt#subtitle:lang=fr-FR -tmp D:\ -brand mp42isom -ab dby1 -no-iod D:\DVremux-7.1.mp4

thanks, those are basically the same cmd lines I've been using, by following yusesope's instructions.

my "test results" are limited, since I'm only doing DV movies with DTS audio. I first learned the DV mp4 method few months ago, but once I discovered the method only allowed for ac3 audio, and I wasn't willing to sacrifice lossless audio (and atmos), I stopped paying attention. I'm back in the struggle this time learning a new method has been discovered to preserve DTS-HDMA as pcm, so I've only been testing on these type of DV movies.

p.s. the Angel Heart mp4 that crashes my x700 plays fine via USB directly on my C6, though not the lossless pcm since C6 is not equipped with e-arc, so I don't bother with USB>C6 (and also because the occasional green-screen) and only focusing on working around x700 by my personal preference stated above.

Out of the few DV+DTS movies I've tested with x700: angel heart - crashes within seconds; don't look now - crashes within a few seconds, at the studio canal logo; hannibal - very unstable, sometimes crashes around 1/3 mark, sometimes quit playing at half mark...; 2001 a space odyssey: success; shutter island: success. Like you said, all of them, if tried to skip forward, will trigger x700 hard crash regardless. I wonder if X700 will play nicer with other DV-profiles (other than this method's default 7) when tracks are first demuxed?

[hydrad]

mp4muxer_release --dv-profile 7 --input-file BL.hevc --input-file EL.hevc --output-file output.mp4

The command looks correct, if you have mp4muxer executable file in the same directory than BL.hevc en El.hevc files.
What is this "release" version of mp4muxer, personnaly compiled ?
Can you try with the executable file from here: https://github.com/DolbyLaboratories/dl ... master/bin
I m using mp4muxer_64bits.exe on windows 10 64 bits and it works perfectly. (i did almost 100 dv mp4 files with it )

Sorry for the delay, I didn't get reply notifications

My mp4muxer is not on the same folder. However, I'm not using the complete path, so in reality my command is like

/home/mp4muxer/mp4muxer_release --dv-profile 7 --input-file BL.hevc --input-file EL.hevc --output-file output.mp4

I compiled it personally from the repository, but I'm going to try with the release you pasted.

[RESET_9999]

thanks, those are basically the same cmd lines I've been using, by following yusesope's instructions.

my "test results" are limited, since I'm only doing DV movies with DTS audio. I first learned the DV mp4 method few months ago, but once I discovered the method only allowed for ac3 audio, and I wasn't willing to sacrifice lossless audio (and atmos), I stopped paying attention. I'm back in the struggle this time learning a new method has been discovered to preserve DTS-HDMA as pcm, so I've only been testing on these type of DV movies.

p.s. the Angel Heart mp4 that crashes my x700 plays fine via USB directly on my C6, though not the lossless pcm since C6 is not equipped with e-arc, so I don't bother with USB>C6 (and also because the occasional green-screen) and only focusing on working around x700 by my personal preference stated above.

Out of the few DV+DTS movies I've tested with x700: angel heart - crashes within seconds; don't look now - crashes within a few seconds, at the studio canal logo; hannibal - very unstable, sometimes crashes around 1/3 mark, sometimes quit playing at half mark...; 2001 a space odyssey: success; shutter island: success. Like you said, all of them, if tried to skip forward, will trigger x700 hard crash regardless. I wonder if X700 will play nicer with other DV-profiles (other than this method's default 7) when tracks are first demuxed?

Don't look now and Hannibal are titles that I did not try. I guess they won't work since I'm experiencing the same crash/freeze for Angel Heart.
most of the titles I watched without issues were Atmos converted to lpcm. The shining is in DTSHD and it played perfectly.

on my end, DV single layer profile 5 mp4 created by DVDFAB doesn't work at all with the x700 . they play with messed up colors but the real web-dl single layer DV of Stranger Things season 3 play nicely.
been a while since I tried that though, maybe the new version of dvdfab fixed that.

[powdeau]

I´ve added LPCM to mp4 DL, but the video is lagging on Sony X700 (when I switch to AC3, it plays fine), any ideas please?

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General
Complete name                            : H:\rocketman\DVremux-7.1.mp4
Format                                   : MPEG-4
Format profile                           : Base Media / Version 2
Codec ID                                 : mp42 (isom/mp42/dby1)
File size                                : 67.7 GiB
Duration                                 : 2 h 1 min
Overall bit rate                         : 79.9 Mb/s
Encoded date                             : UTC 2019-10-05 18:34:55
Tagged date                              : UTC 2019-10-05 18:34:55

Video #1
ID                                       : 1
Format                                   : HEVC
Format/Info                              : High Efficiency Video Coding
Commercial name                          : HDR10
Format profile                           : Main 10@L5.1@High
Codec ID                                 : hev1
Codec ID/Info                            : High Efficiency Video Coding
Duration                                 : 2 h 1 min
Bit rate                                 : 62.3 Mb/s
Width                                    : 3 840 pixels
Height                                   : 2 160 pixels
Display aspect ratio                     : 16:9
Frame rate mode                          : Constant
Frame rate                               : 23.976 (24000/1001) FPS
Color space                              : YUV
Chroma subsampling                       : 4:2:0 (Type 2)
Bit depth                                : 10 bits
Bits/(Pixel*Frame)                       : 0.313
Stream size                              : 52.8 GiB (78%)
Default                                  : No
Encoded date                             : UTC 2019-10-05 17:32:47
Tagged date                              : UTC 2019-10-05 19:17:56
Color range                              : Limited
Color primaries                          : BT.2020
Transfer characteristics                 : PQ
Matrix coefficients                      : BT.2020 non-constant
Mastering display color primaries        : Display P3
Mastering display luminance              : min: 0.0010 cd/m2, max: 1000 cd/m2
Maximum Content Light Level              : 1000 cd/m2
Maximum Frame-Average Light Level        : 999 cd/m2
Codec configuration box                  : hvcC

Video #2
ID                                       : 2
Format                                   : HEVC
Format/Info                              : High Efficiency Video Coding
Commercial name                          : HDR10
Format profile                           : Main 10@L5.1@High
Dolby Vision                             : 1.0, dvhe.07.06, EL+RPU
Codec ID                                 : dvhe
Codec ID/Info                            : High Efficiency Video Coding with Dolby Vision
Duration                                 : 2 h 1 min
Bit rate                                 : 7 674 kb/s
Width                                    : 1 920 pixels
Height                                   : 1 080 pixels
Display aspect ratio                     : 16:9
Frame rate mode                          : Constant
Frame rate                               : 23.976 (24000/1001) FPS
Color space                              : YUV
Chroma subsampling                       : 4:2:0 (Type 2)
Bit depth                                : 10 bits
Bits/(Pixel*Frame)                       : 0.154
Stream size                              : 6.50 GiB (10%)
Default                                  : No
Encoded date                             : UTC 2019-10-05 17:32:47
Tagged date                              : UTC 2019-10-05 19:17:56
Color range                              : Limited
Color primaries                          : BT.2020
Transfer characteristics                 : PQ
Matrix coefficients                      : BT.2020 non-constant
Mastering display color primaries        : Display P3
Mastering display luminance              : min: 0.0010 cd/m2, max: 1000 cd/m2
Codec configuration box                  : hvcC+dvcC

Audio #1
ID                                       : 3
Format                                   : AC-3
Format/Info                              : Audio Coding 3
Codec ID                                 : ac-3
Duration                                 : 2 h 1 min
Bit rate mode                            : Constant
Bit rate                                 : 640 kb/s
Channel(s)                               : 2 channels
Sampling rate                            : 48.0 kHz
Bit depth                                : 16 bits
Compression mode                         : Lossy
Stream size                              : 555 MiB (1%)
Language                                 : English
Default                                  : No
Encoded date                             : UTC 2019-10-05 17:32:47
Tagged date                              : UTC 2019-10-05 19:17:56

Audio #2
ID                                       : 4
Format                                   : PCM
Format settings                          : Big / Signed
Codec ID                                 : in24
Duration                                 : 2 h 1 min
Bit rate mode                            : Constant
Bit rate                                 : 9 216 kb/s
Channel(s)                               : 8 channels
Channel layout                           : L R C LFE Ls R Rls Rb
Sampling rate                            : 48.0 kHz
Bit depth                                : 24 bits
Stream size                              : 7.81 GiB (12%)
Language                                 : English
Default                                  : Yes
Alternate group                          : 1
Tagged date                              : UTC 2019-10-05 19:17:56

EDIT: I fixed it by using these steps https://forum.mrmc.tv/viewtopic.php?f=1 ... 425#p25425

[RESET_9999]

I´ve added LPCM to mp4 DL, but the video is lagging on Sony X700 (when I switch to AC3, it plays fine), any ideas please?
EDIT: I fixed it by using these steps https://forum.mrmc.tv/viewtopic.php?f=1 ... 425#p25425

yep, same behavior on my end when the AC3 is the first audio.
but if you add the lpcm first and then the AC3, you can switch between audio without the lag.

sorry, you probably took the first cmd-line I posted.. I remembered and I edited the post an hour after to especially remove that first audio (forced by dvdfab) but yeah its easier just to not use DVDFAB at all.

[hydrad]

I´ve added LPCM to mp4 DL, but the video is lagging on Sony X700 (when I switch to AC3, it plays fine), any ideas please?
EDIT: I fixed it by using these steps https://forum.mrmc.tv/viewtopic.php?f=1 ... 425#p25425

yep, same behavior on my end when the AC3 is the first audio.
but if you add the lpcm first and then the AC3, you can switch between audio without the lag.

So are you guys playing dual layer dolby vision blurays with Atmos having converted the TrueHD to lpcm?
Can you explain that a little bit?

[superfans124]

thanks, those are basically the same cmd lines I've been using, by following yusesope's instructions.

my "test results" are limited, since I'm only doing DV movies with DTS audio. I first learned the DV mp4 method few months ago, but once I discovered the method only allowed for ac3 audio, and I wasn't willing to sacrifice lossless audio (and atmos), I stopped paying attention. I'm back in the struggle this time learning a new method has been discovered to preserve DTS-HDMA as pcm, so I've only been testing on these type of DV movies.

p.s. the Angel Heart mp4 that crashes my x700 plays fine via USB directly on my C6, though not the lossless pcm since C6 is not equipped with e-arc, so I don't bother with USB>C6 (and also because the occasional green-screen) and only focusing on working around x700 by my personal preference stated above.

Out of the few DV+DTS movies I've tested with x700: angel heart - crashes within seconds; don't look now - crashes within a few seconds, at the studio canal logo; hannibal - very unstable, sometimes crashes around 1/3 mark, sometimes quit playing at half mark...; 2001 a space odyssey: success; shutter island: success. Like you said, all of them, if tried to skip forward, will trigger x700 hard crash regardless. I wonder if X700 will play nicer with other DV-profiles (other than this method's default 7) when tracks are first demuxed?

Don't look now and Hannibal are titles that I did not try. I guess they won't work since I'm experiencing the same crash/freeze for Angel Heart.
most of the titles I watched without issues were Atmos converted to lpcm. The shining is in DTSHD and it played perfectly.

on my end, DV single layer profile 5 mp4 created by DVDFAB doesn't work at all with the x700 . they play with messed up colors but the real web-dl single layer DV of Stranger Things season 3 play nicely.
been a while since I tried that though, maybe the new version of dvdfab fixed that.

I tried to back up a few more. Lock Up went smoothly. Lara Croft the Cradle of Life, initially ffmpeg (latest version) threw a ton of error codes "Application provided invalid, non monotonically increasing dts to muxer", not sure what it means, but still worked with the dts-hdma track. I switched back to txMuxer to the video streams, then mp4muxer > mp4box, worked in the end.

another capability of x700 that I really enjoy is DLNA server support, so I could stream the DV mp4 directly from my plex server and let X700 process the dual-layer DV, to keep my media library all in one organized place, and don't have to mess with plug-n-unplug USB devices. Except the major limitation of x700 that it only equips with 100mb ethernet port, all the really high bitrate titles: the Shining (constantly 90mb-110mbps), Hannibal (good amount of 80-90mbps) stutter due to bandwidth limitation, whereas no stutter when fed via USB.

Have you looked into a replacement player for the x700 lately? I wonder if there's a good alternative solution priced between x700 and gawdly oppo 203...

[hydrad]

thanks, those are basically the same cmd lines I've been using, by following yusesope's instructions.

my "test results" are limited, since I'm only doing DV movies with DTS audio. I first learned the DV mp4 method few months ago, but once I discovered the method only allowed for ac3 audio, and I wasn't willing to sacrifice lossless audio (and atmos), I stopped paying attention. I'm back in the struggle this time learning a new method has been discovered to preserve DTS-HDMA as pcm, so I've only been testing on these type of DV movies.

p.s. the Angel Heart mp4 that crashes my x700 plays fine via USB directly on my C6, though not the lossless pcm since C6 is not equipped with e-arc, so I don't bother with USB>C6 (and also because the occasional green-screen) and only focusing on working around x700 by my personal preference stated above.

Out of the few DV+DTS movies I've tested with x700: angel heart - crashes within seconds; don't look now - crashes within a few seconds, at the studio canal logo; hannibal - very unstable, sometimes crashes around 1/3 mark, sometimes quit playing at half mark...; 2001 a space odyssey: success; shutter island: success. Like you said, all of them, if tried to skip forward, will trigger x700 hard crash regardless. I wonder if X700 will play nicer with other DV-profiles (other than this method's default 7) when tracks are first demuxed?

Don't look now and Hannibal are titles that I did not try. I guess they won't work since I'm experiencing the same crash/freeze for Angel Heart.
most of the titles I watched without issues were Atmos converted to lpcm. The shining is in DTSHD and it played perfectly.

on my end, DV single layer profile 5 mp4 created by DVDFAB doesn't work at all with the x700 . they play with messed up colors but the real web-dl single layer DV of Stranger Things season 3 play nicely.
been a while since I tried that though, maybe the new version of dvdfab fixed that.

I tried to back up a few more. Lock Up went smoothly. Lara Croft the Cradle of Life, initially ffmpeg (latest version) threw a ton of error codes "Application provided invalid, non monotonically increasing dts to muxer", not sure what it means, but still worked with the dts-hdma track. I switched back to txMuxer to the video streams, then mp4muxer > mp4box, worked in the end.

another capability of x700 that I really enjoy is DLNA server support, so I could stream the DV mp4 directly from my plex server and let X700 process the dual-layer DV, to keep my media library all in one organized place, and don't have to mess with plug-n-unplug USB devices. Except the major limitation of x700 that it only equips with 100mb ethernet port, all the really high bitrate titles: the Shining (constantly 90mb-110mbps), Hannibal (good amount of 80-90mbps) stutter due to bandwidth limitation, whereas no stutter when fed via USB.

Have you looked into a replacement player for the x700 lately? I wonder if there's a good alternative solution priced between x700 and gawdly oppo 203...

Are you talking about Sony UBP-X700B?

I didn't even knew there was a device capable of playing Dual Layer remuxes and lossless passtrought!

And it's also not very expensive!

The Ethernet thing is a bummer but where I would place it sits next to the wifi receiver.

Can you confirm this device plays everything?

[Smanet]

Hi, could you please help me how can I get truehd audio file from m2ts, then convert it to lpcm and attach it to mp4 file (created with DVDFab) with mp4box?
Thank you!

audio:

Code: Select all

ffmpeg.exe -i X:\bluray.m2ts -map 0:2 -c:a pcm_s24be -ar 48000 -rf64 auto X:\lpcm.mov

Hi, new here but I have played a lot with my AppleTV and @yusesope instructions to get the best video/audio on my 4k backups.
So far, I can get a single layer DV + LPCM 7.1 (converted from TrueHD/Atmos) using the same command as above.
I believe I know the answer, but am I right to believe that in this way we lose Atmos? I have learned that AppleTV doesn't allow to play Atmos anyway, but I was wondering if Atmos is lost in the conversion anyway.
I have a 5.1.4 speaker setup and I'm finding myself conflicted on the following:

1) Watch the backup with DV + LPCM 7.1 (converted from TrueHD)
2) Watch the backup with DV + DTS-MA (I believe this should work with MP4 but I haven't tested it. Or is it worth more to convert DTS-MA to LPCM instead of TrueHD, again if possible?)
3) Watch the backup without DV but with Atmos (is there any appreciable difference with HDR10? I have a LG C8)

Are you talking about Sony UBP-X700B?

I didn't even knew there was a device capable of playing Dual Layer remuxes and lossless passtrought!

And it's also not very expensive!

The Ethernet thing is a bummer but where I would place it sits next to the wifi receiver.

Can you confirm this device plays everything?

I'm interested in that topic too, I'm currently testing Dvdfab ripper to have the single layer DV, but if the Sony UBP-X700B works with dual layers and lossless passthrough that could be definitely a solution (and maybe cheaper than a software solution in the long run). I would use a USB SSD drive for that.

Thanks in advance!

[superfans124]

Hi, new here but I have played a lot with my AppleTV and @yusesope instructions to get the best video/audio on my 4k backups.
So far, I can get a single layer DV + LPCM 7.1 (converted from TrueHD/Atmos) using the same command as above.
I believe I know the answer, but am I right to believe that in this way we lose Atmos? I have learned that AppleTV doesn't allow to play Atmos anyway, but I was wondering if Atmos is lost in the conversion anyway.
I have a 5.1.4 speaker setup and I'm finding myself conflicted on the following:

1) Watch the backup with DV + LPCM 7.1 (converted from TrueHD)
2) Watch the backup with DV + DTS-MA (I believe this should work with MP4 but I haven't tested it. Or is it worth more to convert DTS-MA to LPCM instead of TrueHD, again if possible?)
3) Watch the backup without DV but with Atmos (is there any appreciable difference with HDR10? I have a LG C8)

Are you talking about Sony UBP-X700B?

I didn't even knew there was a device capable of playing Dual Layer remuxes and lossless passtrought!

And it's also not very expensive!

The Ethernet thing is a bummer but where I would place it sits next to the wifi receiver.

Can you confirm this device plays everything?

I'm interested in that topic too, I'm currently testing Dvdfab ripper to have the single layer DV, but if the Sony UBP-X700B works with dual layers and lossless passthrough that could be definitely a solution (and maybe cheaper than a software solution in the long run). I would use a USB SSD drive for that.

Thanks in advance!

I can make some comments regarding Sony x700, but you have to take everything I say with a heavy dose of caveat:
1. I haven't been paying attention to 4K HT hardware for almost a year, to just enjoy what I have, so I have no clue what's now out there, what's available that might be a better option.
2. I didn't buy the x700 to solve a specific problem, but found out what I already had can do things, while having its own unique quirks and features. It's a very Jerry-rigging approach of things.

it certainly does NOT play EVERYTHING. According to REST_9999 it handles most DV MP4 remux of TrueHD/Atmos track very well, from my limited exeprience with DV+DTS-HDMA remuxes, not that great. Like we've mentioned earlier, when fast forwarding a MP4 DV remux, the x700 will hard crash forcing you to unplug its power to hard reboot. It's definitely an unofficial capability that "just happens to work, to a certain degree". But it's hard to pin point culprit in a chain of blame: player hardware? software update? UHD ripper drive hardware? software update? demux/remuxing programs, version updates, specific line of commands? nobody knows! Like I said, very Jerry-rigging approach: patch up a bunch of things from existing tools, and it does something! magical! why does it work (or not) or how to improve it? meh...

There's no way to preserve object-based metadata (atmos/dts-x) in lpcm for your appropriate AV receiver to unfold back to specific atmos/dts-x channels, except to take what's there in the converted lpcm track and use algorithm to up-mix certain audio effects into ceiling channels, "up-mix", but not the same. I'm not content with losing atmos, which is why I only backup DV+DTS-HDMA titles and don't touch DV+Atmos titles.

I have no experience with dvdfab but the yusesope methods.

I do not know the specific wifi capability of X700, it streams netflix 4k HDR content fine, but those are only around 20-30mbps bitrate. Consider how Sony priced X700, to skimp on built quality and features (no gigabit ethernet), I doubt it's equipped with the fastest wifi card to handle 100mbps+ bandwidth. But "does it, or does it not?" IDK.

[Smanet]

I can make some comments regarding Sony x700, but you have to take everything I say with a heavy dose of caveat:
1. I haven't been paying attention to 4K HT hardware for almost a year, to just enjoy what I have, so I have no clue what's now out there, what's available that might be a better option.
2. I didn't buy the x700 to solve a specific problem, but found out what I already had can do things, while having its own unique quirks and features. It's a very Jerry-rigging approach of things.

it certainly does NOT play EVERYTHING. According to REST_9999 it handles most DV MP4 remux of TrueHD/Atmos track very well, from my limited exeprience with DV+DTS-HDMA remuxes, not that great. Like we've mentioned earlier, when fast forwarding a MP4 DV remux, the x700 will hard crash forcing you to unplug its power to hard reboot. It's definitely an unofficial capability that "just happens to work, to a certain degree". But it's hard to pin point culprit in a chain of blame: player hardware? software update? UHD ripper drive hardware? software update? demux/remuxing programs, version updates, specific line of commands? nobody knows! Like I said, very Jerry-rigging approach: patch up a bunch of things from existing tools, and it does something! magical! why does it work (or not) or how to improve it? meh...

There's no way to preserve object-based metadata (atmos/dts-x) in lpcm for your appropriate AV receiver to unfold back to specific atmos/dts-x channels, except to take what's there in the converted lpcm track and use algorithm to up-mix certain audio effects into ceiling channels, "up-mix", but not the same. I'm not content with losing atmos, which is why I only backup DV+DTS-HDMA titles and don't touch DV+Atmos titles.

I have no experience with dvdfab but the yusesope methods.

I do not know the specific wifi capability of X700, it streams netflix 4k HDR content fine, but those are only around 20-30mbps bitrate. Consider how Sony priced X700, to skimp on built quality and features (no gigabit ethernet), I doubt it's equipped with the fastest wifi card to handle 100mbps+ bandwidth. But "does it, or does it not?" IDK.

Thank for the detailed response, I understand that it may not be ideal but it could be a temporary solution to watch DV backups, at least with Atmos.
I will keep an eye on prices and also check if there is anything new, perhaps from Sony again But I am like you, if a movie has been made available with Atmos, I would like to hear it as it has been created.

[speeddemon]

Is there any chance that Matroska may end up eventually supporting conversion of the UHD Blu-ray's Dolby Vision layer into the streaming format's Dolby VIsion and then muxing it into an MKV file?

If it is possible with MP4 then why not MKV?

[SamuriHL]

Is there any chance that Matroska may end up eventually supporting conversion of the UHD Blu-ray's Dolby Vision layer into the streaming format's Dolby VIsion and then muxing it into an MKV file?

If it is possible with MP4 then why not MKV?

This has been discussed before, but, I'm going to go a different route on this one to try to give people a much better understanding of why the answer is NO. And because I don't know the precise technical details, I'm going to use generic explanations for this problem. First, though, you need to know WHY mp4 "works". It's because Dolby released a spec for storing Dolby Vision inside an MP4 container and even released a tool to multiplex it. But that begs the question and technical reason MKV doesn't "support" Dolby Vision...what the hell does it mean "released a spec for storing..."? See, these formats are container formats. I'll use a really bad analogy here. Think of it like a zip file that contains files. Container formats in the video world contain streams. But much like a zip file, you have to know what's stored in the container, where it starts and ends, and how it's stored. That information, similar to a zip file, is stored within a header. For MP4 there are atoms that contain this information, for which the atom data needed to store Dolby Vision is known. MKV stores a header in the file that describes the streams contained within. There is no current spec for storing a Dolby Vision stream within the MKV container. So your next question would be "well, can't someone just make one up?" They....could. But much like having to "unzip" your zip file (man what a bad analogy but I'm really trying to get the point across here), the unzip program needs to know how the files are stored in the container. PKZip, RAR, WinZIP....there are several different standards here that have to be known ahead of time. Which gets us to the bigger issue. Just because you declare a "spec" for storing Dolby Vision in an MKV container, it doesn't mean that splitters, players, renderers, etc...the playback infrastructure....knows about it. So you could store it in an MKV and then not be able to play it because licensed players, the only ones who have the ability to play Dolby Vision in the first place, won't know shit about your spec.

Hopefully this clears up the issue of why it's not happening any time soon once and for all. Bad analogy and all.

[st4evr]

Hopefully this clears up the issue of why it's not happening any time soon once and for all.

Give it another few days/weeks, but we can dream can't we?