Extract and crop video from DVD using mplayer

[PeteTV]

I'm using mplayer on a Mac to extract a video from a DVD, but the result contains black bars all around.

If I play the DVD itself using VLC, the video is in the correct 16:9 aspect ratio, BUT it has black bars on both sides AND top/bottom. In other words, both the video and the VLC window are 16:9, but the video is smaller then the window.

If I use mplayer to extract the video, eg:

mplayer dvd://1 -dumpstream -dumpfile video.vob

and then play video.vob in VLC, the result has the black bars on the sides cropped, but the bars on the top/bottom are still there. In other words, the video is still 16:9, but the VLC window is now 4:3.

When I transfer video.vob to my TiVo (without doing any transcoding), it's back to black bars on the sides and top/bottom. In other words, the aspect ratio is correct (16:9), but it's a small video with respect to the size of the TV screen which is also 16:9.

Is there a way I can run the above mplayer command to extract the video, but also crop all the black bars so I end up with just the 16:9 video and no black bars anywhere?

[dizzie]

I'm sorry I can't comment on mPlayer, but I know what I would do if you haven't tried it - rip with MacTheRipper or RipIt. Or, if it doesn't have copy protection - just drag and drop the desired VOBs to a folder on your hard drive! I hope that helps... : )

[Case]

Does this happen for one particular DVD, or for many/every DVD you've tried?
It is possible, but weird, that the person who encoded the DVD, made it with black all around.
It is also possible to encode a DVD with letterboxing (non-anamorphic widescreen; 16:9 in a 4:3 frame), with the black as part of the video. This happened a lot when 16:9 tvs weren't as common as they are now, and/or the author didn't understand the benefits of anamorphic widescreen.
Many modern tvs have a zoom function to enlarge the video, so that this particular content will fit the screen. (Do not expect a software scaler to perform any better than a hardware scaler in a tv.)

Software cropping would make the frame likely too small for a valid VOB file, so you would need to transcode into a new file. If you want to stay with the VOB file format, you would need to crop AND scale up again with an MPEG-2 encoder.

[PeteTV]

rip with MacTheRipper .... Or, ... just drag and drop the desired VOBs to a folder on your hard drive! ...

Sorry, I wasn't more clear... I believe the way the video was put on the DVD in the first place is the problem. If I play the VOB directly from the DVD I see the same result. In other words, the video has black bars on top/bottom when played in VLC or mplayer.

It is also possible to encode a DVD with letterboxing (non-anamorphic widescreen; 16:9 in a 4:3 frame), with the black as part of the video. This happened a lot when 16:9 tvs weren't as common as they are now, and/or the author didn't understand the benefits of anamorphic widescreen.

It's just this one DVD... at least so far... and I suspect you're correct, the DVD itself was authored with letterboxing in a 4:3 frame.

Many modern tvs have a zoom function to enlarge the video, so that this particular content will fit the screen. (Do not expect a software scaler to perform any better than a hardware scaler in a tv.)

My TV does have a zoom feature... in fact, it's a very nice incremental (from 1-16 steps) proportional zoom... so I can zoom only as much as needed to fill the screen without any distortion or cropping. It's slightly cumbersome to use but well worth it for cases like this. My question about cropping is really more about understanding how to do it.

Software cropping would make the frame likely too small for a valid VOB file, so you would need to transcode into a new file. If you want to stay with the VOB file format, you would need to crop AND scale up again with an MPEG-2 encoder.

According to mplayer (and VLC and ffmpeg), it looks like the video is 720x480 which means the aspect ratio is 1.5, is that right?.

In order to get it to 1.77 (ie 16:9), it would need to be 720x405, correct? Which means I would need to crop say 37 off the top and 38 off the bottom. First, if I did that, would it still need to be scaled? Is that too small for a valid VOB file?

And, if not... exactly how would you crop the top/bottom using mplayer?

I've tried using this to play the vob in mplayer:

mplayer -vf crop=720:405:: video.vob

and it does crop the top/bottom, but not as much as is needed. In order to get all the black removed from the top/bottom I need to use "-vf crop=720:352::". I guess I don't get the math... isn't 720:352 equal to an aspect ratio of 2.05? I'm pretty sure the video itself (w/o black bars) has an aspect ratio of 16:9 because I can use the proportional zoom on my TV (as mentioned above) and it will fill the screen without any cropping or stretching.

At any rate, the "-vf crop..." command only seems to work when PLAYING the video via mplayer. If I try to extract the video using that option it doesn't do any cropping, eg:

mplayer dvd://1 -vf crop=720:352:: -dumpstream -dumpfile video.vob

Do I need to use some other mplayer option to crop while extracting the video as opposed to playing it? Or is it just not possible?