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  1. To the administrator Baldrick
    ----
    Please, my friend, don't lock this topic, if you see my profile, you will see I'm not a regular member, in fact I only ask here about two, three times in a year, I'm an old member from this forum, since 2005 and in many times the search option of the forum helps me a lot. And I think this is not about deblocking a video but it's a question about misuderstanding of the options in mencoder

    And I promisse to you, my friend I will never ask any more question about that subject.

    And please don't ban me. If you feel the will to lock this topic, so please ban me too. I will be sad.
    ----

    Well, In FFDShow video filters we have this



    and probably this will be translated in the command line of mencoder to:

    Code:
    -vf pp=ha:y:n/va:y:n/dr/al:f
    where pp=post-processing and its parameters

    ha=acurate horizontal deblocking
    y - do luminance filtering only (no chrominance).
    n - do chrominance filtering only (no luminance)

    va=acurate vertical deblocking
    y - do luminance filtering only (no chrominance).
    n - do chrominance filtering only (no luminance)

    dr=deringing, al=auto levels and f = fullyrange

    in the fullyrange parameter there is a range from 0 to 255 but I don't know which value use, so I'm using the default one

    I'm using the command-line of

    Code:
    c:\mencoder\mencoder.exe video.avi -ovc lavc -lavcopts vcodec=libxvid:vbitrate=640:vpass=1:autoaspect -nosound -o video_proc.avi -ffourcc XVID -vf pp=ha:y:n/va:y:n/dr/al:f
    c:\mencoder\mencoder.exe video.avi -ovc lavc -lavcopts vcodec=libxvid:vbitrate=640:vpass=2:autoaspect -nosound -o video_proc.avi -ffourcc XVID -vf pp=ha:y:n/va:y:n/dr/al:f
    I read some options in libxbvid codec from libvacodec, including the standard xvid codec (not from libxvid) including the mpeg4 codec vcodec=mpeg4 setting the FourCC code to XVID.

    But the video is still having blocks.

    I tried using the Deblock filter from Avisynth and I tried using MSU Smart Deblocking and MSU Deblocking filters in VirtualDub and I tried using AutoGK too. Including I tried using the .avs file (avisynth) as input video in mencoder.

    But the source AVI file (video.avi) is not blocked and I really need to know how these guys can rip a DVD or reencode a video with low bitrates, like 600, 700kbps, (in my case 640kbps) and the resulting video don't become blocked.

    Please, tell me the tricks, some tips or what I'm doing wrong and which command-line parameters should I use.

    My thanks, my many thanks to everybody and my best, very best regards to everybody here!
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  2. Originally Posted by BlooderButcher
    But the source AVI file (video.avi) is not blocked and I really need to know how these guys can rip a DVD or reencode a video with low bitrates, like 600, 700kbps, (in my case 640kbps) and the resulting video don't become blocked.
    The difference is they are using a 6000-8000kbps DVD source, you are using a low quality 700kbps xvid already heavily compressed source.

    You have to use a higher bitrate to compensate. You can't expect to reduce the size and keep decent quality, unless you use the original source, or use a better compression method like h264. This was all explained in the other thread. You said xvid q=2 looked fine, but was too big, so try a q=3, or q=4 until you have a balance that is acceptable to you

    As for the options, I don't use mencoder so I can't help you there, but I can tell you no amount of filtering or options will help you given the constraints you have placed
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  3. poisondeatray: You helped me a lot in the other thread, thank you man

    If I use a quantizer value of 2 or bitrate like 4000kbps and let the file become bigger could I reencode it back to the low bitrate using two passes. Will I lose the quality?

    And there are some options in the -xvidencopts to pass to xvid codec in mencoder like these

    Code:
    vhq=2:bvhq=1:chroma_opt:quant_type=mpeg
    Well, according with the Mplayer documentation this is equal to high-quality.

    Could somebody give me a good command line to use in mencoder? :P
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  4. Originally Posted by BlooderButcher
    If I use a quantizer value of 2 or bitrate like 4000kbps and let the file become bigger could I reencode it back to the low bitrate using two passes. Will I lose the quality?
    No, it will become worse

    Everytime you re-encode using a lossy codec, you lose "1 more round" of quality. You really, really want to avoid any re-encoding.

    I highly doubt mencoder will give you what you want.

    If i can recally you wanted to crop and resize? If it's just for playback you can do that in ffdshow without altering the original xvid video (i.e. it crops and resizes while playing back)
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  5. I solved!

    Code:
    c:\mencoder\mencoder.exe video.avi -nosound -ovc xvid -xvidencopts vhq=2:bvhq=1:chroma_opt:quant_type=mpeg:bitrate=640:pass=1:autoaspect -ffourcc DIVX -o video_proc.avi -vf pp=ha:y:n:128:7/va:y:n:128:7/dr
    c:\mencoder\mencoder.exe video.avi -nosound -ovc xvid -xvidencopts vhq=2:bvhq=1:chroma_opt:quant_type=mpeg:bitrate=640:pass=2:autoaspect -ffourcc DIVX -o video_proc.avi -vf pp=ha:y:n:128:7/va:y:n:128:7/dr
    By the way, if we change the "vhq=2" to "vhq=4" the video quality will be better, but this will take a long time to encode.

    Anyway... thanks to everybody here specially 'poisondeathray'. Maybe in next year I'll be back. See ya!

    Hey, "I'll be back", this remember "The Terminator"
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