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```
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Uniform time
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============
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Have the default time_base be one that can work with all major time_bases, e.g.:
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1/24
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1/25
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1/30
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1/60
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1001/30000 (29.97)
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1001/24000 (23.98)
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1001/60000
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Consider making a uniform time class:
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```
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class Time():
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# Tracks the last value set.
|
| ... | ... | @@ -28,34 +19,4 @@ class Time(): |
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def rebase(self, new_base):
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# Replace the base, and rescale i (if important)
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Time
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|
====
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- What are the various rates and scales?
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see: http://ffmpeg.org/pipermail/libav-user/2011-December/001041.html
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see: http://stackoverflow.com/questions/12234949/ffmpeg-time-unit-explanation-and-av-seek-frame-method/16739755#16739755
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- Stream.guessed_rate or AVStream.r_frame_rate:
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FFmpeg's guess as to the frame rate. Often 24/1.
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- Stream.average_rate or AVStream.avg_frame_rate:
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|
Average frame rate that has been inspected in the file. This is what VLC
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reports in the media information. Often near 24/1.
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It may calculate this from 20 frames; see: http://ffmpeg.org/doxygen/trunk/libavformat_2utils_8c_source.html#l02768
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- Stream.time_base or AVStream.time_base:
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Duration of one time unit for AVStream times.
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- Stream.rate or CodecContext.time_base:
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The length of a single frame as reported by the file. Sometimes 1/24,
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sometimes really really wrong.
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possibilities for discrepencies:
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- .mov supports a fixed frame rate
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- .mp4 does not support a fixed frame rate?
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- see: http://ffmpeg.org/doxygen/trunk/libavformat_2utils_8c_source.html#l02647
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``` |
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\ No newline at end of file |
