macos - 在ffmpeg中保留时间码？

Question

我正在运行一个脚本，该脚本使 proress 422 代理在 ffmpeg 中进行编辑，但文件上的时间码似乎丢失或无效。
我正在使用的参数:

ffmpeg -i file.mov -vcodec prores -profile:v 0 -an file.mov

有没有办法从原始文件中保留时间码？
我也来过 ffmbc 似乎更适合这个，但它只适用于 linux。有什么方法可以为 osx 编译吗？
我在 osx 10.8.4

Answer 1

从手册页:
http://ffmpeg.org/ffmpeg.html

‘-copyts’
Do not process input timestamps, but keep their values without trying to sanitize them. In particular, do not remove the initial start time offset value.

Note that, depending on the ‘vsync’ option or on specific muxer processing (e.g. in case the format option ‘avoid_negative_ts’ is enabled) the output timestamps may mismatch with the input timestamps even when this option is selected.

‘-copytb mode’
Specify how to set the encoder timebase when stream copying. mode is an integer numeric value, and can assume one of the following values:

‘1’
Use the demuxer timebase.

The time base is copied to the output encoder from the corresponding input demuxer. This is sometimes required to avoid non monotonically increasing timestamps when copying video streams with variable frame rate.

‘0’
Use the decoder timebase.

The time base is copied to the output encoder from the corresponding input decoder.

‘-1’
Try to make the choice automatically, in order to generate a sane output.

Default value is -1.