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  1. Member
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    Search Comp PM
    Hi guys

    I want to crop a logo (located on top left) from a video file. If not crop, then I am ok to BLUR the area as well. I am looking for some software which can do it easily and fast.
    I tried 2 software, they did the job but the encoding/post processing was too slow. Is there any way to make that fast ?
    In short I don't want to convert the file (AVC/MP3) but only crop/blur the file and save it.
    I am not sure whether its possible or not or does we require to convert the whole video after cropping/blurring.
    Please recommend some tool to make it happen.
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  2. 2 way to deal with this:
    1. Blur the logo and save the corresponding video, this requires a re-encode (in practice this is also true for crop or mask) which may be undesirable.
    OR
    2. Use a video player feature (crop, mask or blur) to perform this operation in realtime each time you play the file. VLC has a built-in feature, but .hlsl pixel shaders or an avisynth script can be used in mpc-hc https://www.videohelp.com/software/Media-Player-Classic-Home-Cinema / mpc-be.

    to "Blur" the logo, different algorithms may be used, which different levels of success depending on the actual logo.
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  3. Either way I think you will have to re encode. Probably easiest to just put a tight black rectangle over the logo in video edit and export and the same frame rate and bit rate and aspect ratio.

    You say it 'is slow' when you tried to do it. Is that because it is a very long video or perhaps you have a slow computer?

    I can render out 30 minutes of video in 1080p in around 27 minutes on a i7 laptop. that seems an acceptable time frame to me...

    How long did it take when you tried it, and what length is the video you are trying to work with?
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  4. Originally Posted by new93 View Post
    I tried 2 software, they did the job but the encoding/post processing was too slow.
    Then use faster encoder settings. For example, there is a 100 fold difference in encoding speed between x264's Ultrafast (fastest) and Placebo (slowest) presets.
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  5. If your listed specs are up to date, i3 2120 is a dual core sandy bridge model - maybe using quick sync would be faster for encoding than dual core CPU
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  6. Member
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    I am using 8th Gen i5 processor and I have 1050ti GPU. I think x264/x265 can be converted fast with GPU power but I don't know how to do it.
    Since I have to re encode, I think I will have to invest time in it. Any software which can crop/blur video and also use GPU power to make encoding faster ?
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  7. Originally Posted by butterw View Post
    2 way to deal with this:
    1. Blur the logo and save the corresponding video, this requires a re-encode (in practice this is also true for crop or mask) which may be undesirable.
    OR
    2. Use a video player feature (crop, mask or blur) to perform this operation in realtime each time you play the file. VLC has a built-in feature, but .hlsl pixel shaders or an avisynth script can be used in mpc-hc https://www.videohelp.com/software/Media-Player-Classic-Home-Cinema / mpc-be.

    to "Blur" the logo, different algorithms may be used, which different levels of success depending on the actual logo.
    1. Correction: It is not in fact necessary to re-encode, if the player you use supports crop parameter in the video bitstream (x264, hevc).
    From my test (with mpc-hc/be, vlc) this works (lossless remux) in mp4 with ffmpeg.

    Code:
    ffmpeg -i "input.mp4" -codec copy -bsf:v h264_metadata=crop_top=128 "output_cropped.mp4"
    this will crop 128 pixels from the top of a mp4/x264 video, if the player supports the video bitstream tag.

    for x265: hevc_metadata=crop_top=128

    mkvtoolnix has something similar, but it was ignored by the player last time I tested it.
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  8. Member
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    Is there any gui to work with ffmpeg?
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