Divx Plus general compatibility questions and specs

[OvejaNegra]

I make this:
http://labs.divx.com/node/15406
post at the divx labs and nobody answer me.
Well maybe better luck here!

Since this is more related to the divx plus (mkv) format specs and not to H264 encoding, i think this is the right place to post.

Thanks.

PD:
Any one have one of those Lg players that plays DivX HD?
Are they working with your old mkv files encoded with x264?
:thanks:

[nurbs]

High profile @ level 4.0
AAC audio
no idea about the subtitles, I would hope vobsub
no idea if the handle SAR that isn't 1:1, but again since they use mkv they should at least repect the resizing specified by the container

[roozhou]

High profile @ level 4.0
AAC audio
no idea about the subtitles, I would hope vobsub
no idea if the handle SAR that isn't 1:1, but again since they use mkv they should at least repect the resizing specified by the container
AFAIK most players on PC only respect SAR in bitstream.

[OvejaNegra]

Well, since they are using mkv, i think i can add a SRT track and a Vobsub track. Maybe if the SRT track is the first one, the player will recognize it and ignore the vobsub track if is not recognized. But maybe it will refuse to play the entire file!!

They have not specs published and i dont want to encode stuff and buy a future player only to find that the files cannot be played :)

[Atak_Snajpera]

Default Level 4.0 profile in ripbot is already DIVX HD compatible. Don't forget that recommended audio codec is AAC! However it does not mean that your device won't play AC3 or DTS core for example. AAC must be supported in 100% by all Divx HD certified devices. Support for different audio format depends of manufactures' will. Frankly I would be very surprised if Blu-Ray player with DivX HD logo couldn't decode at least AC3/DTS-core !

[OvejaNegra]

Well actually the audio thing does not worries me.
I'm positive sure about support for AC3 (and maybe DTS)
But there is no info about subtitles, or how the players will handle unknow tracks (if the player just ingnores those tracks, then you can always encode a bullet-proof AAC audio tracks just to be sure and another bullet-proof SRT track)

Then you can add any unsupported track if you want. But if that is not part of the standard specs, then its a different thing.

:mad:

[nurbs]

My experience with hardware players that support MKV is that they'll simply ignore tracks they can't decode. For instance I tried to play a file with both SRT and vobsub and it would only show the SRT tracks. Those weren't DivX HD certified of course. My own choice is a WD TV (http://www.wdc.com/en/products/Products.asp?DriveID=735) and I use AVC, AAC and vobsubs in MKV, but it can play almost anything that one would commonly use. If the people implementing it are reasonable the players will handle anything the device would normally play, like all the formats supported by blu-ray in case of a blu-ray player, plus AAC and probably a couple of subtitle formats for the DivX HD certification.

[OvejaNegra]

THANKS NURBS.

Yes of course i still want to hear teh divx position about this. But i will start using a default srt and AAC track on my files and i will encode all my files with x264 and the buffer they propose.
Nurbs: What about the aspect ratio? Your player adapts to that too?

I found this (read the entire page)
http://support.divx.com/faq/view/supportFAQen049/DivX-7-Frequently-Asked-Questions

Part of my questions has been answerd on that link.

[nurbs]

I normally encode 1:1, but I tested some things when I got it and anamorphic works. I directly set the aspect ratio with --sar x:y in x264, so that definitely works. No idea what happens if you only specify it in the container, but that would be unusual anyway.

[OvejaNegra]

got it.
i will start signaling the aspect ratio on the video stream

(and on the video container)

One question:
when i add a video track on mkmerge the aspect ratio field is visible. that means it can write the aspect ratio on the video stream or is just writing the aspect ratio on the VIDEO TRACK of the mkv file?

[nurbs]

Doesn't change the bitstrean, it just writes it to the mkv file. If you don't specify it manually it will automatically get the right value from the stream. I can't check now, but as far as I remember the field is actually for playback resolution, but most (all?) players just treat it like an aspect ratio.

[Mosu]

Doesn't change the bitstrean, it just writes it to the mkv file. If you don't specify it manually it will automatically get the right value from the stream. I can't check now, but as far as I remember the field is actually for playback resolution, but most (all?) players just treat it like an aspect ratio.

That is correct. Both parts of it: what mkvmerge does, how players should treat those fields and how they're actually treated.

[OvejaNegra]

Thanks to all!!
Mosu:
Then waht should i put on that field?
Actually i put tha PAR value (1.8, 0.95, etc) AFTER cropping (i use gordian knot to make the calculations)
Until now it works ok. But maybe with future players it wont.

What should i put?

[Mosu]

Then waht should i put on that field?
Actually i put tha PAR value (1.8, 0.95, etc) AFTER cropping

What you should put into DisplayWidth and DisplayHeight are the pixel width/height of the playback area you want to achieve. If the quotient DisplayWidth/DisplayHeight is the pixel/sample aspect ratio then it's most certainly wrong; it must equal the desired display aspect ratio.

[GodofaGap]

Also, a PAR/SAR do not change with just cropping.

[OvejaNegra]

ok, now im lost again:

>>> entering analog mode <<< :)

I have my NTSC DVD (4:3)
The picture resolution is 720 X 480
After cropping to the active picture (702 X 480)
702 * 0.911 = 640
0.911 is my pixel aspect ratio

640 X 480 is a 4:3 picture----> because -> 640 / 4 * 3 = 480 or 640 / 480 = 4 / 3 (1.333)
4:3 or 1.333 is my picture aspect ratio.

Now, if im doing anamorphic encoding (preserve the shape of the picture without any correction) but i crop some black bars, my picture aspect ratio is not the same.
For example if i crop my DVD to 680 X 480, for a correct display my new (after cropping) picture aspect ratio is 1.292 (using GK for the calculations)
if i apply that to resize my picture to a correct shape (the same the player will do) my new picture should be 480 * 1.292= 620 X 480

please correct me if im wrong.
PAR is picture ascpect ratio? (the proportions of the picture)
or PAR is pixel aspect ratio (the value for correct the shape of the picture in the analog world)

1.292 is the value i always put on THAT field on mkvtoolnix (or the needed after cropping)
I always get a correct picture after that.
Im wrong?

[Mosu]

PAR is usually the pixel aspect ratio, also called sample aspect ratio (SAR).

I don't really have time to explain the usual calculation at the moment; suffice to say that if you DON'T put anything into DisplayWidth/DisplayHeight or mmg's aspect ratio drop down box mkvmerge will automatically figure out the correct values for DisplayWidth/Height on its own by taking the physical resolution and pixel aspect ratio stored in the bitstream into account.

[OvejaNegra]

ok thanks.

This stuff about SAR/PAR is always a mess for me.

[regret]

PD:
Any one have one of those Lg players that plays DivX HD?
Are they working with your old mkv files encoded with x264?
:thanks:

I have an lg player that plays divx hd and and also x264 encoded mkvs.

Most 1080p and 720p mkvs play properly but some don't. I don't know why. Problems I have seen are slow picture refresh of part of the screen, for example a moving arm stays on the screen until the whole image is refreshed. Or parts of the skin look shiny metallic, a bit like the terminator.
These problematic mkvs can be re-encoded and the problem is solved.
Micro-HD mkvs always play well.

My player doesn't recognize the chapter points of mkvs. I was disappointed at first but the search button makes up for this loss.

My player does not recogize vob sub streams in the mkv. Sorry no pretty colors, very very disappointing.

For audio the player recognizes ac3, dts, aac, aac sbr, mp3, wav.
No ogg, no flac.

It plays avi, mkv, mp4. Maybe wmv: I dont have any wmv.
No m4v.

One more disappointment. My player won't play avchd from a flash drive. I have to burn a dvd.

Jf the mkv is incomplete, say the last 3 MB is missing, the player scans the mkv very slowly, 10minutes to scan an hour of video. And you can't go backwards. Now that wouldn't happen with an avi.

[OvejaNegra]

THANK YOU!!

What you use to re-encode those problematic mkv?
If you have one mkv with one srt and one vob sub stream (both) what happens?
.............. what is Micro-HD?? :(

Thanks!!!

[regret]

The player will play what it can and ignore the rest.
It will play the srt but not the vobsub.
If the container has more than one video stream it will just play the first stream.
I can't find a way to access the second stream.

I'm not an expert encoder, just do enough to get the job done when I have to.
I use Handbrake/Linux, start with the Apple TV preset, then build complexity from that base.

Micro-HD are just encodes from Blu ray sources that are High Definition and really compressed. Say 350-500mb for a 90 minute 720p movie.

The player is tough. I had one mkv where the streams were corrupted for about 15 seconds half way into the movie(Totoro). No software player I had could get past the corruption. The hardware player effortlessly skipped over the problem.