[MKV] problem with AR/sizes

[tozzy]

Hey guys.
First of all I must say that I am not really into video conversion stuff, so please kindly excuse me if this was already discussed somewhere, but I wasn't able to find any solution.
So I have an MKV and, through mediainfo, I found out its properties are:

ID                                       : 1
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Format profile                           : High@L5.1
Format settings, CABAC                   : Yes
Format settings, ReFrames                : 16 frames
Codec ID                                 : V_MPEG4/ISO/AVC
Duration                                 : 58mn 58s
Bit rate                                 : 1 193 Kbps
Width                                    : 720 pixels
Height                                   : 576 pixels
Display aspect ratio                     : 16:9
Original display aspect ratio            : 5:4
Frame rate mode                          : Constant
Frame rate                               : 25.000 fps
Standard                                 : PAL
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Bits/(Pixel*Frame)                       : 0.115
Stream size                              : 492 MiB (81%)
Title                                    : Doctor Who S01EXmas 2005 Christmas Invasion HR DVDRip HQ Edition x264-D734
Writing library                          : x264 core 54
Encoding settings                        : cabac=1 / ref=16 / deblock=1:-2:-1 / analyse=0x3:0x133 / me=umh / subme=6 / brdo=1 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=2 / 8x8dct=1 / cqm=0 / deadzone=21,11 / chroma_qp_offset=0 / threads=3 / nr=0 / decimate=1 / mbaff=0 / bframes=3 / b_pyramid=1 / b_adapt=1 / b_bias=0 / direct=3 / wpredb=1 / bime=1 / keyint=250 / keyint_min=25 / scenecut=40(pre) / rc=2pass / bitrate=1193 / ratetol=1.0 / rceq='blurCplx^(1-qComp)' / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / ip_ratio=1.40 / pb_ratio=1.30
Language                                 : Russian
Default                                  : Yes
Forced                                   : No

So, as you can see, there are 2 ARs - 16:9 & 5:4.
At the same time, I have a PVR device which can play H.264 MKV (the files are played fine) and my old 4:3 TV. The device has an option to play 16:9 videos correctly, with pillar boxes, but it is not such a big trouble anyway
But that MKV video I am talking about (see info above) doesn't play well no matter do I set 4:3 or 16:9 mode, everything looks stretched, I guess because the actual AR is 5:4 (strange one - see this for the first time).
If I extract the video stream (getting a raw h264 video) it is 5:4 AR.
So is there a way to playback this video (by somehow resizing it or changing AR or whatever)?

I tried using MP4Box and remux the video into an MP4 changing AR, like this:

mp4box.exe -add "Track1.h264:par=16:9" -add "Track2.mp3" -v -new out.mp4

The output video is played well (the picture is fine) but the pillar boxes in that case are way too big (about half of the screen size) and the MP4 video has a strange AR of 2.33.

[Baldrick]

Can you post a screenshot or a short example( using makesample) from the video?

As I think you have to reconvert....

[sneaker]

Try mkvmerge with following options:
Set "Displayer width / height" to either 785 x 576 (4:3) or 1047 x 576 (16:9)
In the output tab set additional option: --engage remove_bitstream_ar_info

If none of the DARs fit you have to play a bit with the values until you find one that matches.

[Cornucopia]

It comes from a DVD, so it MUST be either 4:3 or 16:9.

Scott

[tozzy]

Try mkvmerge with following options:
Set "Displayer width / height" to either 785 x 576 (4:3) or 1047 x 576 (16:9)
In the output tab set additional option: --engage remove_bitstream_ar_info

If none of the DARs fit you have to play a bit with the values until you find one that matches.

Thanks for your input, did what you've suggested, but now in mediainfo:

Display aspect ratio                     : 4:3
Original display aspect ratio            : 5:4

So that original 5:4 is left.

It comes from a DVD, so it MUST be either 4:3 or 16:9.

Scott

I would agree with you and most DVDs are 4:3 or 16:9, but it is likely that this case is different.

[jagabo]

I would agree with you and most DVDs are 4:3 or 16:9, but it is likely that this case is different.

No, DVDs only come in two flavors 4:3 and 16:9 DAR. If the original DVD plays properly it's one of those display aspect ratios. Any source that's not one of those aspect ratios (a 2.35:1 movie, for example) will be cropped to one of those ratios or have letterbox or pillarbox bars added to fill out the frame.

Of course, it's possible somebody mistreated a source and screwed up the aspect ratio. If that's the case you have to figure out what SAR or DAR is appropriate and resize the frame or flag the AR in your output file.

[sneaker]

Thanks for your input, did what you've suggested, but now in mediainfo:

Display aspect ratio                     : 4:3
Original display aspect ratio            : 5:4

So that original 5:4 is left.

Either I'm remembering wrong or MediaInfo behavior has changed. I thought it only displayed "Original display aspect ratio" when SAR flag in H.264 bitstream was present but I can confirm it now always shows. So "--engage remove_bitstream_ar_info" might or might not have changed anything in the stream.