Margulus
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Posted - 2008.10.10 05:05:00 -
[1]
Simply stated:
wmv9 is compatible and available (every windows box can do it, natively, without additional config or effort). It's actually far superior to DivX in compression and quality when measured in similar file sizes. It's easy, free, and in most cases the option offered most commonly by windows platform video editors.
h.264/x264 is an excellent modern compression method. Surpassingly high quality, smaller filesize. The caveat is that to get super high quality out of a small file, you must encode under level 4 or unrestricted profiling. This basically means that a majority of PC's not made within the last 1.5 years or so will have issues playing it back smoothly. More modern video cards are starting to incorporate decoding assistance functions, but in the main, it remains an option (in high proflie at least) only for people with good hardware.
The other issue with h.264/x264 comes with the actual encoding. Not only does it take a considerable order of magnitude longer, it's also far less user friendly. Very few video editing platforms support output directly to a high profile h.264 format, so you must convert into it, and it requires decent knowledge of digital video concepts like colorspace, decimation, and fps concepts of both your original format and output target format.
The other issue I hear most about is the loss of audio to video synch when converting to h.264, most commonly when converting from wmv9. A quick tip for people who are trying to do a convert, you need to be sure you tell your script to force the DirectShow (in the case of wmv9)to render all source frames at the target fps, as wmv will occasionally drop framerates to save from having to render things like blackouts and the like which incidentally is where the desynch comes from. in an avisynth script, this is accomplished with the following:
DirectShowSource("c:\...\...\somevid.wmv",fps=[actual target fps],convertfps=true,audio=false)
This tells the encoder to load the wmv via the DirectShow grapher, that the intended fps is xxx, and that it should force the framerate output to match the intended framerate, with no audio rendering. This solves 90% of synch issues.
Sorry for the length
 tl;dr= DivX is crap, wmv9 is ok and common, h.264 rocks hard if you can hack it, random tips at the end |