We appreciate your association with IAA, and for keeping us informed.
All we can do is ask, and all you can do is what you can do. No worries.
A Bad Think - Short Street (Atmos) out now.
- Thread starter Sal1950
- Start date
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All we can do is ask, and all you can do is what you can do. No worries.
Absolutely, I love what the folks do over there at IAA, I'm perfectly happy with downloads.
I've already got a huge stack of boxes and cases pilling up in the music room again.
BTW, I'd love to get more artwork included in the way of the pdf that was included in
Ben Craven - Monsters From The ID download. That was really KOOL.
TIA, Sal
I'm not an expert on this, so correct me if this is wrong.
mp4 is a lossy codec.
m4a is lossless. An m4a file is a container format and can hold a variety of data.
A conversion from mkv (also lossless) to m4a should be a lossless process.
MMH converts mkv to m4a that play back nicely in full Atmos through kodi for me.
Am I missing some intermediate lossy conversion in MMH that takes place?
Following
I hope it doesn't turn out to be too boring or confusing. Let's go...
MP4 file format is a container (MPEG-4). MP4 is not a codec.
As a container it can contain audio, video and other things such as subtitles and still images.
The Audio (or video) can be ‘encoded’ using different codecs. Each different codec can be lossless or lossy.
M4A file extension is normally used for a container MP4 that has a single ‘audio’ thing inside. A single audio ‘track’. It would be as (MPEG-4 Audio)
You can just rename M4A to MP4 file extension (without any conversion tool) and that can be interesting for some players, such as Oppo that cannot play M4A single audio file, but plays the same file just renamed to MP4.
Normally, MP4 or M4A file containers are used to ‘contain’ tracks with lossy audio codecs, such as DD+ (Dolby Digital Plus) or DD+/JOC for Dolby Atmos lossy.
MKV is another type of container (for audio, video, subtitles, etc.)
MKV container is normally used to contain tracks with lossless codecs such as Dolby TrueHD (with or without Atmos), DTS HD-MA, but could also contain lossy codecs.
It is very instructive to install the MediaInfo tool in your PC, to ‘see’ what different video and audio ‘tracks’ a container file MP4,M4A, MKV has inside. You then can see what ‘codec’ is in each ‘audio or video track, and see if it is lossy or lossless by its name.
Using MMH or other tools you have to differentiate two types of conversion, if available in the tool:
- Just a ‘repack’ moving the same video/audio tracks from one container to other without changing them. Lossy remains lossy, and lossless remains lossless. Also known as 'remux'.
- Video/audio track conversion. By decoding it and reencoding using a different ‘codec’ you can convert from lossless to lossy, losing quality and reducing file size. Or from lossy to lossless, increasing file size but without increasing the quality.
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Thanks for the explanation. It makes sense
Back to the title subject... I streamed this title the other day. I liked it quite a bit.
Back to the title subject... I streamed this title the other day. I liked it quite a bit.
Thanks, a great post showing there are no hard and fast rules
for the various containers. It can get quite confusing at times.
I have mediainfo installed in my PCLinuxOS desktop and this is
the report I get on the A Bad Thing - Short Street - Passion Play.mkv
file as downloaded directly from IAA.
This was explained very thoroughly in the previous post, but I'll add that you can change the extension on .mkv file to .mka and its the same principle as renaming a .mp4 file to .m4a. If you do this, you'll need to make sure your Windows view settings are setup to show file extensions in the filename.
However, since you use Kodi, converting MKV to M4A using MMH is the way to go, since M4A files can be tagged. MKA files are buggy at best trying to tag, and yes the conversion is lossless. It's not really a conversion at all, its taking what's inside the mkv container and putting in an m4a container.
anandchristi
Senior Member
Quick question on this. Why is it only playing in 7.1? I downloaded Bruce's new album and have the same problem!
Try setting your player to force bitstream output.
anandchristi
Senior Member
Thanks a lot Baggy, that worked. Brilliant!
We can both thank Morten Lindberg, from 2L.
I was experiencing the same thing with his recent MKV release of David Lang: alleluia amen - meditation remix.
He straightened me right out!
I try this with Lifelike Atmos mkv and doesn’t work. With bitstream output i don’t get any sound, with auto output 7.1 but not Atmos
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