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  1. Hi ....

    please download my source HD 1920x1080 interlaced 4:2:2

    https://www.dropbox.com/s/829iziwuetpdqm4/source422.MXF?dl=0

    I would like encode in MP4 4:2:0 using ffmpeg

    Code:
    ffmpeg -y -i source422.mxf -s 1920x1080 -vf scale=interl=1 -c:v libx264 -profile:v main -pix_fmt yuv420p -an HaveCromaGhost.MP4
    but this output [attached] have a croma ghost problem artifacts on video or I mistake?

    Please consider this second commandline:

    Code:
    ffmpeg -y -i source422.mxf  -vf scale=interl=1 -c:v libx264 -profile:v main -pix_fmt yuv420p -an OK.MP4
    This output [attached] is correct, don't have croma ghost.

    So I wonder: why using the -S 1920x1080 the
    Code:
    -vf scale=interl=1
    parameter don't act?

    Is there a way to keep the -S 1920x1080 but let act as right the
    Code:
    -vf scale=interl=1
    ? thanks
    Image Attached Files
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  2. Did you try
    -vf scale=width=1920:height=1080:interl=1
    ?
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  3. Originally Posted by sneaker View Post
    Did you try
    -vf scale=width=1920:height=1080:interl=1
    ?

    Code:
     
    ffmpeg -y -i source422.mxf -s 1920x1080 -vf scale=width=1920:height=1080:interl=1 -c:v libx264 -profile:v main -pix_fmt yuv420p -an Test2.MP4
    yes cat , but the croma ghost persist

    if possible I would keep (for various reasons) the -s 1920x1080 line, so I wonder if there is a way to encode well keeping this line
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  4. I assume these "various reasons" are beyond human understanding.
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  5. Oh yes in fact there are some feline reasons
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  6. 1920x1080 => 1920x1080 is a no-opt ; nothing happens . If you changed the dimensions, then it would be bad and you need to use the other way with -vf scale

    The problem here is -pix_fmt is using progressive scaling for 422=>420 (The dimensions of the chroma planes are being scaled in progressive fashion instead of interlaced). The solution is to move -pix_fmt to -vf scale using interl=1 to indicate interlaced 422=>420

    I assume you want interlaced encoding (MBAFF) , TFF, flagged 709
    Code:
    ffmpeg -i source422.MXF -s 1920x1080 -vf scale=w=1920:h=1080:interl=1,format=pix_fmts=yuv420p -flags +ildct+ilme -c:v libx264 -x264opts tff=1:colorprim=bt709:transfer=bt709:colormatrix=bt709 -profile:v main -an IM_A_BAD_CAT.mp4
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  7. Originally Posted by poisondeathray View Post
    1920x1080 => 1920x1080 is a no-opt
    Oh, the source is 1080 already? I didn't read properly...
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  8. Originally Posted by poisondeathray View Post
    1920x1080 => 1920x1080 is a no-opt ; nothing happens . If you changed the dimensions, then it would be bad and you need to use the other way with -vf scale

    The problem here is -pix_fmt is using progressive scaling for 422=>420 (The dimensions of the chroma planes are being scaled in progressive fashion instead of interlaced). The solution is to move -pix_fmt to -vf scale using interl=1 to indicate interlaced 422=>420

    I assume you want interlaced encoding (MBAFF) , TFF, flagged 709
    Code:
    ffmpeg -i source422.MXF -s 1920x1080 -vf scale=w=1920:h=1080:interl=1,format=pix_fmts=yuv420p -flags +ildct+ilme -c:v libx264 -x264opts tff=1:colorprim=bt709:transfer=bt709:colormatrix=bt709 -profile:v main -an IM_A_BAD_CAT.mp4
    Image
    [Attachment 42274 - Click to enlarge]


    it works well
    thanks
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