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47 lines
1.3 KiB
Plaintext
47 lines
1.3 KiB
Plaintext
1. prepare your video files for Ben:
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Use ffmpeg2theora or ffmpeg with vp8, vorbis, mkv.
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When using theora, try to use a video width and height that are a multiple of
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16. Currently theora decoding displays strange borders, if size is not a
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multiple of 16.
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Try to use an audio sampling rate of 44100 for the vorbis audio. If the
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automatic resampling of the alsa OSS emulation is triggered, quality degrades
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a lot. Alternatively use 'mplayer -af resample=44100:1:1' on playback.
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For encoding try to use libtheora 1.2 ("ptalarbvorm") which improves visual
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qality a lot compared to previous versions. Always encode with
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constant-quality *not* giving a bitrate target.
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Here's an example encoding command:
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ffmpeg2theora -o output.ogv input.avi \
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-v8 -x320 -y176 \
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-a0 --channels 2 --samplerate 44100
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Yielding a pretty high visual quality (-v8 i.e. "80%"). Use -v6 for
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approximately half the bitrate with moderate quality.
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2. play your files with Ben:
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mplayer output.ogv
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In case sample rate doesn't match 48000 the default will be to perform quick
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resampling, introducing noticeable quality degradation. Add -af
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resample=44100:0:1 to improve audio quality at the cost of a few percent of
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CPU usage.
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(Assumptions:
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the following options should be set in your ~/.mplayer/config:
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volume=10
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vo=cvidix
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screenw=320
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screenh=240
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fs=1
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ac=tremor
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quiet=1
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)
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