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  1. I have some SD PAL interlaced AVI files that were captured from SD tapes (720x576). It shows to have been captured at 28.8 Mb/S.

    I want to convert these to MP4 (H264) so that I can play them on TV etc. What is a a reasonable bitrate to encode them to MP4? 28.8Mb/s seems to be overkill for SD video IMO.

    Format : AVI
    Format/Info : Audio Video Interleave
    Commercial name : DV
    Format profile : OpenDML
    File size : 19.0 GiB
    Duration : 1 h 31 min
    Overall bit rate : 29.8 Mb/s
    Writing library : yzer
    TAPE : sclive

    Video
    ID : 0
    Format : DV
    Codec ID : dvsd
    Codec ID/Hint : Sony
    Duration : 1 h 31 min
    Bit rate : 28.8 Mb/s
    Width : 720 pixels
    Height : 576 pixels
    Display aspect ratio : 4:3
    Frame rate : 25.000 FPS
    Standard : PAL
    Color space : YUV
    Compression mode : Lossy
    Bits/(Pixel*Frame) : 2.778
    Stream size : 18.4 GiB (97%)
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  2. If you are going o use app for conversion that uses x264 encoder (most of them if not all of them can use it) you may select CRF encoding when you select quality rather than bitrate. It is one pass only and encoder distributes bitrate depending on source.

    So if choosing x264 encoder, making audio H.264 you CRF (or Handbrake uses RF name for it) value about 17 -18. The lower the better quality but video size increases. While lowering CRF you get to the point where visually you see no differences and size balloons up only. The sweet spot quality/video sizes for DV tapes is about 17-18. That value would give you bitrates something overall 4 to 6 Mbits/s.
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  3. If it was me, I would go with around 8000 from edit, or in handbrake choose an SD pre set
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  4. Member
    Join Date
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    Seems to be DV video, approx 13GB p/hour.
    Don't choose a fixed bitrate, for mp4/AVC video, choose CRF encoding (constant quality in Handbrake)
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  5. Member
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    May 2014
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    Memphis TN, US
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    Doesn't matter how it's re-encoded. Analog to DV is damaged to begin with.
    - My sister Ann's brother
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  6. Mr. Computer Geek dannyboy48888's Avatar
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    May 2007
    Location
    Texas, USA
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    At crf 16 with x264 my encodes fall anywhere from .6-4mbps all depends on the source noise etc. The average is 1.5mpbs
    if all else fails read the manual
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  7. Originally Posted by akkers View Post
    I have some SD PAL interlaced AVI files that were captured from SD tapes (720x576). It shows to have been captured at 28.8 Mb/S
    For your files a bitrate of 1Mb/sec is more than enough. Try to make a re-encode with my smart FFMpeg gui, setting a crf 25.
    https://forum.videohelp.com/threads/395425-New-small-GUI-for-FFmpeg
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  8. CRF 25 is pretty low quality. Use something more sensible like 18.
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  9. Originally Posted by jagabo View Post
    CRF 25 is pretty low quality. Use something more sensible like 18.
    CRF18 with source 28 Mb/s will give you a result of 6-12 Mb/s. This seems like a lot to me.
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  10. Originally Posted by ProWo View Post
    Originally Posted by jagabo View Post
    CRF 25 is pretty low quality. Use something more sensible like 18.
    CRF18 with source 28 Mb/s will give you a result of 6-12 Mb/s.
    It depends on the material. VHS caps without any noise reduction will probably be around that. My DV camcorder caps come out around to 3 Mb/s.

    The poster will have to decide for himself what compromise between quality and size he wants to make.
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  11. The DVD spec, which is what this video's resolution matches, allowed for a maximum of 9.8 Mb/s for video; in theory H264 would allow a 50% bit rate savings over MPEG-2.

    Based on the above, if the OP was to convert his DV format capture to a DVD compatible mpeg-2, he would use 9.8 Mb/s, so it stands to reason that if he uses an H264 encoder he should use 4.9 Mb/s if he wants similar quality to what a good MPEG-2 encoder could do at max DVD spec bit rates or even more than 4.9 Mb/s if he wants potentially even higher quality video.

    I see no sense in encoding his capture at absurdly low 1 Mb/s that someone recommended. We also have to take into account that he will most likely want to deinterlace as well.
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  12. Originally Posted by sophisticles View Post
    The DVD spec, which is what this video's resolution matches, allowed for a maximum of 9.8 Mb/s for video; in theory H264 would allow a 50% bit rate savings over MPEG-2.

    Based on the above, if the OP was to convert his DV format capture to a DVD compatible mpeg-2, he would use 9.8 Mb/s, so it stands to reason that if he uses an H264 encoder he should use 4.9 Mb/s if he wants similar quality to what a good MPEG-2 encoder could do at max DVD spec bit rates or even more than 4.9 Mb/s if he wants potentially even higher quality video.

    I see no sense in encoding his capture at absurdly low 1 Mb/s that someone recommended. We also have to take into account that he will most likely want to deinterlace as well.
    He's not creating a DVD, so what's the sense in recommending a bitrate for an encoder based on the maximum bitrate that can be used with an older encoder for DVDs? It's like saying that if the maximum bitrate for DVD AC3 audio is 448kbps, if you encode the audio as AAC you should encode it at 224kbps. There's no direct relationship between the two in respect to quality. Haven't you ever seen a horrible looking DVD with a bitrate of 9.8Mb/s and nice clean looking video at the same bitrate? It makes far more sense to select a particular quality for x264 and let the bitrate be whatever it will be.

    It didn't take much looking to find a 720p encode that came in at 450kb/s lower than a DVD encode, both at CRF18, because the 720p video was much cleaner. Should I have encoded the DVD based on mpeg2 DVD bitrates and the 720p video based on Bluray bitrates instead?
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    Last edited by hello_hello; 27th Feb 2020 at 03:37.
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