VideoHelp Forum
+ Reply to Thread
Results 1 to 10 of 10
Thread
  1. I'm capturing some old NTSC VHS tapes that I recorded of TV shows many years ago. I capture at 720x480. Which is the correct method to get the proper aspect ratio of 4:3?

    1. Crop off the overscan (which is usually 8 pixels on each side) to get 704x480 and then resize to 640x480.

    2. Crop overscan, AddBorders to make it 720x480 again, and then resize to 640x480.
    Quote Quote  
  2. Capturing Memories dellsam34's Avatar
    Join Date
    Jan 2016
    Location
    Member Since 2005, Re-joined in 2016
    Search PM
    In most cases you slightly blur the frame horizontally by down sizing the resolution, It is a lot better to put an aspect ratio flag into the video than having to physically change its structure.
    Quote Quote  
  3. Member Cornucopia's Avatar
    Join Date
    Oct 2001
    Location
    Deep in the Heart of Texas
    Search PM
    Or, #3: leave it alone and play in a player that accepts & understands nonsquare PAR. (It should already have the flag if captured & saved properly).

    Scott
    Quote Quote  
  4. Originally Posted by Cornucopia View Post
    Or, #3: leave it alone and play in a player that accepts & understands nonsquare PAR. (It should already have the flag if captured & saved properly).

    Scott
    I'm capturing with VDub and using Lagarith. As far as I know the avi does not have a flag for playing the correct aspect ratio. I'm saving the final encodes to PC and don't need them to be DVD compliant. They are only going to be played on a PC. I have many many hours of video so I encode with x264 and resize to save space.
    Quote Quote  
  5. Forget resizing since any further processing like that will degrade the image quality more.

    If it's playing on the pc, vlc, mphc, etc have the option to set the video aspect ratio upon playback manually, even crop during playback.
    (E.g. Right click on the video in mphc to bring up the menu)

    This tells the pc how to correctly display the video.
    Quote Quote  
  6. Originally Posted by babygdav View Post
    Forget resizing since any further processing like that will degrade the image quality more.

    If it's playing on the pc, vlc, mphc, etc have the option to set the video aspect ratio upon playback manually, even crop during playback.
    (E.g. Right click on the video in mphc to bring up the menu)

    This tells the pc how to correctly display the video.
    I'm not concerned about it losing a little bit of quality. I'm more concerned about space. I'm fine with the quality. I just needed to know the proper way to get the correct aspect ratio.
    Quote Quote  
  7. You're capturing VHS tapes with barely 300 lines of resolution across the full frame. Resizing from 704 to 640 isn't going to hurt them at all.
    Quote Quote  
  8. Capturing Memories dellsam34's Avatar
    Join Date
    Jan 2016
    Location
    Member Since 2005, Re-joined in 2016
    Search PM
    Actually the horizontal resolution of VHS is inferior than the vertical one, It is barely over an equivalent of 200 pixels compared to 240 vertical (300 is extreme), down sizing it you end up with like 177 active VHS pixels, That's bad. Flagging the aspect ratio can be done during the compression, Something like this:

    Code:
    ffmpeg -i Input.avi -vf "crop=w=704:h=480:x=0:y=0,scale=w=-1:h=-1:interl=1,format=yuv420p,setsar=sar=8/9" -flags +ildct+ilme -c:v libx264 -crf 10 -x264opts bff=1:colorprim=smpte170m:transfer=smpte170m:colormatrix=smpte170m:force-cfr -c:a aac -b:a 192k Output.mp4
    x value I believe is the number of pixels you want the crop to start from the edge of the frame.
    Quote Quote  
  9. Originally Posted by jagabo View Post
    You're capturing VHS tapes with barely 300 lines of resolution across the full frame. Resizing from 704 to 640 isn't going to hurt them at all.
    I agree.
    Quote Quote  



Similar Threads

Visit our sponsor! Try DVDFab and backup Blu-rays!