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  1. Member
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    Jul 2007
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    United Kingdom
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    Super basic thing but something that is annoying me. All I want to do is take snapshots that are automatically deinterlaced and at the correct size, but it seems different programs have their own ideas of what that is.

    The source material is DVD so all videos are generally 704/20x480/576 depending on PAL/NTSC. So all I want is a screenshot in the original size, but like I say different programs have different results. I can take screenshots of a 720x480 DVD in PowerDVD 8 and it comes out at 640x480 but the same DVD capped with VLC comes out at 720x540. Both different, and neither the original resolution of the DVD/MPEG2!

    Is it something to do with square/rectangular pixels or something? What should be the 'correct' size once I cap these DVDs, and what is the best program for the job?
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  2. Member
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    Nov 2009
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    Germany
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    You might want to try MPC-HC. Works great.

    ggtop
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  3. Member
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    Ok thanks I used that, and it did produce a cap at 720x480 but that visually looked wrong, it looked wide. So I was thinking, should they be at 640x480, since that is 4:3?

    Would this be right:

    720x480 NTSC video = 640x480 screenshot
    720x576 PAL video = 768x576 screenshot

    Pixel shapes/sizes on PC and TV and all that jazz still confuse me.
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  4. Member
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    Anyone?
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  5. Originally Posted by Killer3737 View Post
    Ok thanks I used that, and it did produce a cap at 720x480 but that visually looked wrong, it looked wide.
    NTSC DVD uses a 3:2 frame size to encode a 4:3 or 16:9 picture. That's why VLC and PowerDVD were resizing -- to correct for the aspect ratio. VLC by stretching the frame vertically, PowerDVD by squeezing the frame horizontally. Use any 4:3 or 16:9 frame size you want.

    PAL uses a 5:4 frame size (720x576) but the same display aspect ratios.
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  6. Member
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    Right ok, thanks. On several occasions I've tried to understand the whole frame size/pixel shape thing and never really got it. Am I right in what I've said above then, 640x480 and 7680x576 would be the most "correct" sized screenshot? Visually they look right anyway.
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  7. Member
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    Nov 2005
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    i had the same issue...i would screen-shot with MPC or Vobblanker and the aspect ratio was wrong so i went the long way around to get it done right

    opened the vob file in VirtualDubMod...right click on the screen and choose the right aspect ratio

    Click image for larger version

Name:	dfgdfg.jpg
Views:	149
Size:	73.7 KB
ID:	5642

    hit the "print-screen" button on your keyboard

    open up an image editor..i use paint.net..paste the image in

    Click image for larger version

Name:	ertrer.jpg
Views:	132
Size:	152.4 KB
ID:	5643

    ..then crop the part of the image you just print screened and voila

    Click image for larger version

Name:	tyt8y.jpg
Views:	179
Size:	87.1 KB
ID:	5644

    Click image for larger version

Name:	gdfgdf.jpg
Views:	539
Size:	27.3 KB
ID:	5645
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  8. Video Restorer lordsmurf's Avatar
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    Never use DVD player software for screen caps.
    VirtualDub is best for most all video caps.

    Also read this: How to take a screenshot / Take picture of computer screen
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  9. VirtualDub does have some problems:

    It doesn't handle interlaced YV12 properly. The chroma channels will be messed up. Especially noticeable with animated videos (cartoons, anime, etc.). Set your decoder to output YUY2 instead of YV12, if you can. One example:

    https://forum.videohelp.com/threads/322333-Lines-on-my-rendered-videos?p=1996768&viewfu...=1#post1996768

    It always converts YUV to RGB with the rec.601 matrix. That is usually what you want to do with standard definition video. But high definition video usually uses the rec.709 matrix. The difference in colors between the two aren't huge. Most people wouldn't notice without seeing them side by side.
    Last edited by jagabo; 15th Feb 2011 at 18:00.
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