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When using ffmpeg to convert from .wmv files to .flv files, I find that either the quality is too low or the bps is too high. I am working on a Ubuntu Linux installation. Any suggestions?

The bps must be within 500k.

Command line line for high quality:

ffmpeg -i '$raw_video_path' -ab 64 -ar 44100 -b 300k -r 30 -s 720x480 -sameq $temp_flv

This produces a very high quality, but 10 times the allowed bps. Command line for low quality:

ffmpeg -i '$raw_video_path' -copyts -ar 44100 -s 320x240 $temp_flv

This produces too poor a quality with 90% of the the allowed bps.

slhck
  • 235,242

2 Answers2

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The flv format by itself is very low-quality. If you REALLY need to use flv you have to choose: either you stick with youtube-ish quality, or you pump up the bitrate, or, alternatively, you can preprocess the video. What does this mean? Well, to get a denoiser that takes out some of the frequencies, enhancing compressability and outputting a smooth image at the cost of CPU time. It works, and it works really well, plus depending on the content it may look even better. Remember, DCT blocks analyze frequencies, and when they can't reproduce high frequency they come up with crap.

I would use Avisynth's DCTFilter, But I don't know if it would work in Ubuntu. Very good speed and enhances compressability remarkably (It's more of a low-bitrate preprocessor than a denoiser, and the only drawback is when you have very sharp edges, like in anime)

Camilo Martin
  • 2,794
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Last time I encoded video I used Winff. It lets you set some option. It may work for you. Basically it is a grafical interface for ffmpeg.

Ordago
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