...the story of the 2 black strips

MKV playback, recompression, remuxing, codec packs, players, howtos, etc.
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Skyman1
Posts: 5
Joined: Fri Sep 14, 2012 10:19 pm

...the story of the 2 black strips

Post by Skyman1 » Fri Sep 14, 2012 11:06 pm

Hello everybody!
I am new... and my english it's not quite good...

I am using this amazing application... I am looking in the next 30 days to purchase it but... there is something that do not convince me.

The conversion is very good, also if you can not regulate the dimensione of the file... but my dubt is aobut the 2 dark strips at up and botom of the screen... I suppose that this is something that someone else had already talk about it, do you know if there will be a fix about it?

I don't wat to use for the moment other conversion program... most of the time I convert BD from my new BD reader in FULLHD 1080...

paulster
Posts: 200
Joined: Sat Aug 20, 2011 6:54 pm

Re: ...the story of the 2 black strips

Post by paulster » Fri Sep 14, 2012 11:46 pm

The black strips are actually encoded in the original video stream since all 1080i/p Blu-rays are actually stored at 1920x1080 on disc regardless of the aspect ratio of the movie they contain.

Since MakeMKV doesn't process the video stream at all it can't remove them as that would require re-encoding the particular segment of the stream.

Skyman1
Posts: 5
Joined: Fri Sep 14, 2012 10:19 pm

Re: ...the story of the 2 black strips

Post by Skyman1 » Sat Sep 15, 2012 9:24 am

paulster wrote:The black strips are actually encoded in the original video stream since all 1080i/p Blu-rays are actually stored at 1920x1080 on disc regardless of the aspect ratio of the movie they contain.

Since MakeMKV doesn't process the video stream at all it can't remove them as that would require re-encoding the particular segment of the stream.
DO you think that in the new update they will process the video stream to let this happen?

If I am going to extend the video to fit it to my TV... this is not possibile with this video encoding... different from the original one and different from other MKV downloaded from the web.

crowfax
Posts: 972
Joined: Thu Feb 18, 2010 5:55 am

Re: ...the story of the 2 black strips

Post by crowfax » Sat Sep 15, 2012 5:52 pm

MakeMKV is not an encoder. What you are requesting would require an encoder.

Rip with MakeMKV first, then encode with Handbrake (http://www.handbrake.fr) if you want to alter aspects of the video.
Home Theater PC: Assassin HTPC, XBMCbuntu 12.0 (Frodo), Intel i5 3570k 3.4 GHz Ivy Bridge w/ HD 4000, LG BD-ROM
Playback Devices: Mede8er MED600X3D, MyGica EnjoyTV 120, Xtreamer SideWinder 3, Crystal Acoustics MediaMatchBox

PatHawks
Posts: 11
Joined: Thu Oct 04, 2012 5:56 pm

Re: ...the story of the 2 black strips

Post by PatHawks » Thu Oct 04, 2012 5:59 pm

I know mkvmerge can set a crop paramater that will effectively remove the black bars without needing to transcode the video.
Combined with something like Handbrake's automatic letterbox detection, it seems like it should be possible for MakeMKV to set this information automatically.

Romansh
Posts: 873
Joined: Sat Jan 22, 2011 7:09 pm

Re: ...the story of the 2 black strips

Post by Romansh » Thu Oct 04, 2012 7:44 pm

Automatic letterbox detection requires that video decoders be added to MakeMKV.

PatHawks
Posts: 11
Joined: Thu Oct 04, 2012 5:56 pm

Re: ...the story of the 2 black strips

Post by PatHawks » Thu Oct 04, 2012 7:46 pm

Perhaps automatic letterbox detection is beyond the scope of MakeMKV, but it would be nice to at least be able to manually set crop information.

Romansh
Posts: 873
Joined: Sat Jan 22, 2011 7:09 pm

Re: ...the story of the 2 black strips

Post by Romansh » Thu Oct 04, 2012 9:27 pm

PatHawks wrote:Perhaps automatic letterbox detection is beyond the scope of MakeMKV, but it would be nice to at least be able to manually set crop information.
But, to what end?

PatHawks
Posts: 11
Joined: Thu Oct 04, 2012 5:56 pm

Re: ...the story of the 2 black strips

Post by PatHawks » Thu Oct 04, 2012 10:13 pm

Romansh wrote:But, to what end?
When I play a 4x3 video on my 4x3 projector with VLC, it windowboxes the video by default.
If, however, I add proper crop metadata with mkvmerge, the projector will display the video properly in full frame.

VLC is not the only media player that respects crop data. Players that do not recognize the information will play the video the same way they do now, so there does not appear to be any significant disadvantage.

fryk.
Posts: 35
Joined: Tue Oct 09, 2012 7:57 am

Re: ...the story of the 2 black strips

Post by fryk. » Tue Oct 23, 2012 8:23 am

PatHawks wrote:I know mkvmerge can set a crop paramater that will effectively remove the black bars without needing to transcode the video...
That's interesting, but I can't find this crop option in MKVMerge. Can you show it please? Imo there is not such a parameter.

gbooker
Posts: 10
Joined: Mon Jul 02, 2012 12:47 am

Re: ...the story of the 2 black strips

Post by gbooker » Wed Oct 24, 2012 2:14 am

According to the specs, there are crop parameters (search the page for crop). The issue is whether a player supports them. I've tried a few of them before and found players that just ignore the settings, but I haven't tried the crop ones yet. You should be able to set these parameters using mkvpropedit -set-.... I found a video where the person is doing the same sort of thing with pixel width and height. I've not played with mkvpropedit enough to really determine if this is the correct way to do such things.

fryk.
Posts: 35
Joined: Tue Oct 09, 2012 7:57 am

Re: ...the story of the 2 black strips

Post by fryk. » Wed Oct 24, 2012 3:59 pm

Yes, you are right. The following command is initializing the crop parameters:

Code: Select all

mkvpropedit test.mkv --edit track:v1 --add pixel-crop-top=Y1 --add pixel-crop-bottom=Y2
.. and modifying:

Code: Select all

mkvpropedit test.mkv --edit track:v1 --set pixel-crop-top=Y3 --set pixel-crop-bottom=Y4
.. and removing:

Code: Select all

mkvpropedit test.mkv --edit track:v1 --delete pixel-crop-top --delete pixel-crop-bottom
mkvinfo shoes (for Y3 = 50 and Y4 = 70):

Code: Select all

|  + Language: und
|  + Video track
|   + Pixel width: 1920
|   + Pixel height: 800
|   + Display width: 1920
|   + Display height: 800
|   + Interlaced: 0
|   + Pixel crop top: 50
|   + Pixel crop bottom: 70
The VLC respects the crop date, MPC not.
Thank you for the video link.

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