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Crop or 'zoom' [losslessly] MPEG2 stream in MKV

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Sakura90:
Hi guys :3

I have some DVDs I want to remux into MKV. But the video has black bars all around as supposedly the video is 2.35:1.



Changing AR doesn't work because of the black bars, I have to 'zoom' manually from inside the player. Mkvmerge has a "cropping" function but it seems players wipe their asses with it. Mkvinfo correctly shows the cropping, so I assume Mkvmerge correctly wrote the cropping to the MKV.

Mkvinfo:
(click to show/hide)(MKVInfo) + EBML head
(MKVInfo) |+ EBML version: 1
(MKVInfo) |+ EBML read version: 1
(MKVInfo) |+ EBML maximum ID length: 4
(MKVInfo) |+ EBML maximum size length: 8
(MKVInfo) |+ Doc type: matroska
(MKVInfo) |+ Doc type version: 2
(MKVInfo) |+ Doc type read version: 2
(MKVInfo) + Segment, size 2675343039
(MKVInfo) |+ Seek head
(MKVInfo) | + Seek entry
(MKVInfo) |  + Seek ID: 0x15 0x49 0xa9 0x66 (KaxInfo)
(MKVInfo) |  + Seek position: 4099
(MKVInfo) | + Seek entry
(MKVInfo) |  + Seek ID: 0x16 0x54 0xae 0x6b (KaxTracks)
(MKVInfo) |  + Seek position: 4262
(MKVInfo) | + Seek entry
(MKVInfo) |  + Seek ID: 0x1c 0x53 0xbb 0x6b (KaxCues)
(MKVInfo) |  + Seek position: 2675218279
(MKVInfo) |+ EbmlVoid (size: 4044)
(MKVInfo) |+ Segment information
(MKVInfo) | + Timecode scale: 1000000
(MKVInfo) | + Muxing application: libebml v1.2.0 + libmatroska v1.1.0
(MKVInfo) | + Writing application: mkvmerge v4.7.0 ('Just Like You Imagined') built on Apr 21 2011 01:13:14
(MKVInfo) | + Duration: 3242.339s (00:54:02.339)
(MKVInfo) | + Date: Mon Jul 18 16:57:43 2011 UTC
(MKVInfo) | + Segment UID: 0xa7 0xfd 0x92 0x31 0xa9 0xc4 0x25 0xc9 0x90 0xc9 0x65 0x2c 0x61 0x8a 0xeb 0x38
(MKVInfo) |+ Segment tracks
(MKVInfo) | + A track
(MKVInfo) |  + Track number: 1
(MKVInfo) |  + Track UID: 3879589784
(MKVInfo) |  + Track type: video
(MKVInfo) |  + Lacing flag: 0
(MKVInfo) |  + MinCache: 2
(MKVInfo) |  + Codec ID: V_MPEG2
(MKVInfo) |  + Default duration: 16.683ms (59.940 fps for a video track)
(MKVInfo) |  + Language: und
(MKVInfo) |  + Video track
(MKVInfo) |   + Interlaced: 1
(MKVInfo) |   + Pixel width: 720
(MKVInfo) |   + Pixel height: 480
(MKVInfo) |   + Display width: 853
(MKVInfo) |   + Display height: 480
(MKVInfo) |   + Pixel crop left: 28
(MKVInfo) |   + Pixel crop top: 70
(MKVInfo) |   + Pixel crop right: 28
(MKVInfo) |   + Pixel crop bottom: 80
(MKVInfo) |  + CodecPrivate, length 164
(MKVInfo) |+ EbmlVoid (size: 879)
(MKVInfo) |+ Cluster


So, I don't want to reencode, first because of quality, second because my PC is crap. Is there any way to set a crop, zoom or whatever so I don't have to manually zoom in the player?

I guess not, as with many other functions, it seems all players have a poor implementation of MKV features :(

KuraiAkumu:
. . . does this count as tech support?

anyways. . .

I don't get it why not just crop and encode to something else... if you really care about quality and little about space you could always use a lossless codec.  You could always use x264 and tweak it so you get at least ..visually identical video...

Sakura90:

--- Quote from: KuraiAkumu on July 19, 2011, 10:39:13 AM ---. . . does this count as tech support?

anyways. . .

I don't get it why not just crop and encode to something else... if you really care about quality and little about space you could always use a lossless codec.  You could always use x264 and tweak it so you get at least ..visually identical video...

--- End quote ---
Well, this looks enough "tech" to me :P

Encode? Encoding at 2-3 fps is a nice pain in the ass. And that's not counting the "testing" bits of encodes to try settings, as I have very little experience encoding. I managed to get decent quality, compared to the original, with CRF 14 and the "grain" preset in x264, at around 5000 kbps. I know bitrate could be lower maybe, I still have to try CRF 16 with that preset to see if I can get away maintaining [some] grain. But I don't have free time to spend the day trying (advanced options at x264 are rather complicated and I don't get most, so it's trial and error here). But even if I had the perfect setting, I can't leave this encoding 24/7 as I need the PC for other uses and I don't have a 2nd one. I used to have a nice Phenom II that was a breeze to encode on, but given money issues, robberies, shit currency exchange, etc, I'm lucky to have something barely enough to play 1080p :-\

Lossless codec? Hehe, ppl take the "I don't care for space" too literally, maybe it's my fault xD. MPEG2 is on the "limits" of size/quality, I can live with it for part of the material I have. But it's not that I care THAT little to use lossless video codecs (I don't even know any of them aside that h264 used to have a "lossless" option somewhere) :P

I just remembered Doom9 forums, I'll try asking there. But as far as I looked up, there's no option other than the mkvmerge 'cropping' that players give a shit about :(

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