VideoHelp Forum


Try DVDFab Video Downloader and rip Netflix video! Or Try DVDFab and copy Blu-rays! or rip iTunes movies!
+ Reply to Thread
Results 1 to 6 of 6
Thread
  1. I'm using VirtualDub 1.7.8 and xVid 1.1.3-27042008

    Let me tell you, guys, my little problem.

    1 - I have an xVid file and this video file has 640x272 and 2.35 of Aspect Ratio.

    2 - This video file has black borders (you know letterboxes) and its picture is stretched with an aspect ratio of 3,04.

    3 - In VirtualDub I cropped it using the "Null Transform" video filter and after I cropped it, this video file now has 640x210 of size.

    4 - As the video file is still stretched I used the "resize" video filter from VirtualDub and I did put it back to 640x272 letting it again with 2.35 of AR. Note: The resize filter is using bicubic (0.60) according with the VirtualDub help the (0.60) offers the best results. I mean mathematicaly.

    5 - Ok, now the picture is looking right, here comes the encoding part.

    6 - I selected the desired bitrate in Xvid configuration dialog, the encoding type is "single pass", and after that I saved the video file with a new filename

    7 - After that I tried playing it again but now when there are a lot of movement in the screen, the video is now blocked and even in a few scenes without movement I see that hateable blocks.

    I need to say I haven' tried all the options in xVid configuration dialog, just a few of them, and I know there are some deblocking filters like "MSU Smart Deblocking" but I don't want to use a deblocking filter as the original video is not blocked.

    What do I need to do? Do I need to select two passes of encoding? What are the best options to encode an xVid file and prevent that hateable video blocking?

    And I'm sorry if my english sounds bad. I'm a brazilian.
    Quote Quote  
  2. If the source has no blocking/pixellation, you can use higher bitrate (2pass) or lower quantizer setting (if using 1pass). Try q=2 (the default is q=4 if you left it untouched) - beware the filesize will get larger

    h264 has inloop deblocking as well (unless you are required to use xvid for some reason)

    PS. your English is fine! I bet my Portuguese & Spanish are worse
    Quote Quote  
  3. Mod Neophyte Super Moderator redwudz's Avatar
    Join Date
    Sep 2002
    Location
    USA
    Search Comp PM
    Two options come to mind. You could use quantizer mode with a quantizer setting of '2'. That should give you close to the same quality as the original, but the filesize will be larger. Or you can do a two pass encode and that may give you close to the same filesize with minimal quality loss if you set the bitrate somewhat higher than the original file.

    Either way, the filesize will be have to be bigger to make up for the quality loss from the re-encoding.

    BTW, your English is fine.
    Quote Quote  
  4. Thank you, guys!!!

    And I'm glad you like my english!
    Quote Quote  
  5. You won't save much bitrate by cropping away the black borders. You can use MPEG4Modifier to fix the aspect ratio without reencoding.
    Quote Quote  
  6. If a quantizer of 2 gives you files that are too big, use a bigger quantizer. I find 3 is a better compromise of file size vs quality. The bigger the quantizer you use the lower the quality. You can use non-integer values too, eg, 2.5.
    Quote Quote  



Similar Threads