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View Full Version : MKVmerge bug? [Anamorphic DAR + Popcorn NMT]

bokonon
15th April 2008, 21:11
taken from http://www.networkedmediatank.com/viewtopic.php?p=26913

I noticed some issues with some MeGUI DVD conversions i was doing where i was doing anamorphic encodes for 16/9 into mkvs. Basically, it seemed to be ignoring the DAR setting, so on my normal svideo connected 4:3 set (no, i'm not blessed with HDTV yet) it was displaying full screen. I did some searching and found the following here (using the zoom button made no difference):

http://www.networkedmediatank.com/viewtopic.php?t=913

However, doing some more testing, i noticed that my mkv out from x264, before i muxed with mkvmerge *did* display with the correct aspect ratio, where the end product did not. Further testing showed that if i muxed the AC3 back in with AVIMux_GUI instead of mkvmerge, it worked fine, and the aspect ratio settings looked to be honored.

So for those who have seen this, try remuxing your mkvs with AVIMux_GUI instead of mkvmerge.


Any idea what could be causing the popcorn NMT to not recognise the DAR tags provided by MKVmerge? How could it differ to the way AVI-mux muxes the file?

Can someone please clear this up :thanks:
SeeMoreDigital
15th April 2008, 21:36
Any idea what could be causing the popcorn NMT to not recognise the DAR tags provided by MKVmerge? How could it differ to the way AVI-mux muxes the file?

Can someone please clear this up :thanks:It's because MKVmerge removes the aspect ratio signalling from the video stream and assigns it within the MKV container!
bokonon
15th April 2008, 22:03
It's because MKVmerge removes the aspect ratio signalling from the video stream and assigns it within the MKV container!

Thanks for the quick response.

Is there a way of turning this off?
SeeMoreDigital
16th April 2008, 08:49
As far as I know, it's not possible to do!
jmnk
17th April 2008, 06:58
some claim that '--engage keep_bitstream_ar_info' option added to mkvmerge will keep AR info in the bitstream. I say 'some' because I could not find that option in any docs or help files for mkvmerge. Can't hurt to try....
kretin
17th April 2008, 07:20
Including "--engage keep_bitstream_ar_info" works for me. My media player ignores the DAR in the container, but using this option keeps the PAR in the h264 stream.

All I need now is a way to fix a couple of mkv's I created before I found this option :(
SeeMoreDigital
17th April 2008, 08:58
Just tried adding the command line: --engage keep_bitstream_ar_info, via: Muxing -> Add command line options... And yes it does work.

Nice one guys :)
buzzqw
17th April 2008, 09:13
Just tried adding the command line: --engage keep_bitstream_ar_info, via: Muxing -> Add command line options... And yes it does work.

option supported by automkv! :D

BHH
SeeMoreDigital
17th April 2008, 18:53
option supported by automkv! :D

BHHCooooool :)
bokonon
17th April 2008, 23:41
Seems that this bug has been sorted out in the April 2008 Firmware - good news!
bokonon
18th April 2008, 00:20
Is it possible that older versions of mkvmerge don't overwrite DAR tags by default?

It is a pain to add '--engage keep_bitstream_ar_info' every time
SeeMoreDigital
18th April 2008, 16:34
Is it possible that older versions of mkvmerge don't overwrite DAR tags by default?

It is a pain to add '--engage keep_bitstream_ar_info' every timeYou could maker it the subject of a "feature request".... And ask the developers ;)