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  1. Hello,

    I've starting using XMedia Recode.
    I have HD MPEG-4AVC/H.264 47.95 fps videos
    I need to convert them in the shortest time to 640x480 or something.
    I don´t care about format, quality or other properties, just the conversion finish as soon as possible
    I've tried saving at 5 fps, very slow process; 23.976 is faster.
    Thank you
    M
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  2. Use h.264 and the ultrafast preset.
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  3. Thanks for your quick answer.

    Profile: Custom
    Format: H.264
    file Extension: h264

    It seems like changing fps rate does not help

    Ultrafast preset is in my case around 8% faster than Medium (default)

    That's the best I can achieve?
    Thank you
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  4. Originally Posted by marciano View Post
    Ultrafast preset is in my case around 8% faster than Medium (default)
    x264 at Ultrafast is typically about 8 times faster than medium if you have no other bottlenecks. So you have a problem elsewhere. Are you performing a lot of filtering? And reducing the frame rate should make the encoding much faster. For example, if you reduced the frame rate to one-frame-per-length-of-the-movie the encoder would only have to compress one frame, so it would be done nearly instantaneously.
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  5. Member
    Join Date: Feb 2004
    Location: Australia
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    I have HD MPEG-4AVC/H.264
    Mind reading again.

    You need to provide some system specifics that is doing the encoding otherwise we have to guess what the problem is.
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  6. Handbrake have faster conversion
    just change in Video tab in x264 preset to Ultrafast
    and use use Handbrake 64bit version if you have 64bit OS
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  7. This is the whole picture.
    That is the format I get from Gopro Hero 3 Black.
    I use it in the fields where I cannot carry lots of equipment.
    To check still images I use a 10" netbook. I know it is far away the best hardware configuration for video. Atom N570, 1Gb ram, Intel GMA 3150/250Mb
    I also want to check videos, they could be around 2Gb
    Obviously it is hard difficult to check them as they are.
    So I am trying to resize and slower framerate.
    I also thought that resizing only 5 frames per second would be faster but it seems there´s anothe problem here.
    Report during 5 fps conversion displays it is processing only 1 fps.
    Report during 23,976 conversion displays it is processing aroun 12 fps: much more frames to process but faster (!)
    I don't get it.
    Thank you all for your help,
    M
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  8. Originally Posted by marciano View Post
    That is the format I get from Gopro Hero 3 Black.
    Report during 5 fps conversion displays it is processing only 1 fps.
    Report during 23,976 conversion displays it is processing aroun 12 fps: much more frames to process but faster (!)
    I don't get it.
    I suspect you're being held back by the speed of decoding the source.

    Reducing the output frame rate to 5 fps decreases your overall conversion speed because the program performs a random seek to every 5th frame rather using linear decoding. Long GOP AVC is designed for linear decoding -- ie, one frame after another. When decompressed this way each frame is only decompressed once. But when you random seek within such a file the decoder usually seeks to the nearest keyframe before the requested frame, then decompresses each frame from that keyframe to the requested frame. This is the safest way to assure the correct frame is returned. The net result with your frame rate reduction is that many frames are decompressed more than once. For example, when the program requests frame 0 the decoder decompresses that frame (a keyframe) and returns it to the program. Then the program requests frame 5, so the decoder goes back to frame 0, decompresses frames 0 to 5, and hands frame 5 to the program. Then when the program requests frame 10 the decompressor goes back to frame 0 AGAIN, decompresses frames 0 to 10, and hands frame 10 to the program. So to encode these 3 frames 18 frames had to be decompressed from the source. Whereas, with linear decoding, compressing the first 3 frames would only require decompressing 3 frames, compressing the first 11 frames would only require decompressing 11 frames.
    Last edited by jagabo; 5th Feb 2014 at 08:20.
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  9. Is there a way to avoid that? I don't need an exact frame rate.
    I also tried Handbrake, converting times are similar. It does not display info during conversion.
    Thanks
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  10. Video Restorer lordsmurf's Avatar
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    A faster CPU.
    Want my help? Ask here! (not via PM!)
    FAQs: Best Blank DiscsBest TBCsBest VCRs for captureRestore VHS
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  11. I meant that issue about 5 fps!
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  12. Member
    Join Date: Mar 2011
    Location: Nova Scotia, Canada
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    Handbrake may be measurably faster but I'd have to see some benchmark results to convince me of it. And it's never seemed particularly fast to be. I can't tell much difference between any encoders I've used using the same settings.

    And I kind of hate to say this but you are simply not going to get decent encoding times with that hardware anyway. It wouldn't play 1080p very well anyway. Maybe the best thing would be to use an encoder that supports batch processing and run it overnight.

    And if you're going to convert to h.264 maube try disabling CABAC. It compresses the file a little more using file compression (not data) but uses more cpu power when you're playing it.
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  13. Originally Posted by Hoser Rob View Post
    And I kind of hate to say this but you are simply not going to get decent encoding times with that hardware anyway. It wouldn't play 1080p very well anyway. Maybe the best thing would be to use an encoder that supports batch processing and run it overnight.
    I assume that. I only want to check Gopro video in the field after filming, in the less possible time. I'm well equipped on my desktop, Mybe I don't need to convert them.
    In QuickTime or Windows Media Player (Win 7) they are played in slow motion and random frame rate (1fps to ...)
    Maybe this would be the fastest way to check framing.
    Originally Posted by Hoser Rob View Post
    And if you're going to convert to h.264 maube try disabling CABAC. It compresses the file a little more using file compression (not data) but uses more cpu power when you're playing it.
    I don't have that format option in H.264
    Thank you all
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  14. CABAC is disabled when using the ultrafast preset in x264.

    There are some conversion programs that can use the graphics card to decompress the source video. But you have to have a graphics card that supports that.
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