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.
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Thread: Fastest conversion
Use h.264 and the ultrafast preset.
Thanks for your quick answer.
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?
I have HD MPEG-4AVC/H.264
You need to provide some system specifics that is doing the encoding otherwise we have to guess what the problem is.
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
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,
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 09:20.
I meant that issue about 5 fps!
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.
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.
Thank you all
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.