ffmpeg视频压缩速度
I watch a lot of sports and recently I've become fascinated with some of the methodologies they use to illustrate events within the game. I don't have their advanced TV software or hardware, of course, but I do have a love for ffmpeg, which allows me to do everything from to change , , and more.
我看了很多体育比赛，最近我对他们用来说明比赛中事件的一些方法很着迷。 我当然没有他们先进的电视软件或硬件，但是我确实喜欢ffmpeg，这使我能够做所有事情，从到更改 ， ，以及更多。
One of my favorite TV sports illustration techniques is speeding video up (time-lapse) or slowing it way down (slo-mo replay); naturally I wanted to know how to manipulate video speed with ffmpeg. It turns out all you need to do is pass in filter with a PTS () value:
我最喜欢的电视体育插画技术之一是提高视频播放速度(延时)或降低视频播放速度(慢动作回放)。 自然，我想知道如何使用ffmpeg操纵视频速度。 事实证明，您需要做的只是传递带有PTS( )值的过滤器：
更快的视频速度 (Faster Video Speed)
ffmpeg -i input.mp4 -filter:v "setpts=0.5*PTS" output.mp4
较慢的视频速度 (Slower Video Speed)
ffmpeg -i input.mp4 -filter:v "setpts=2*PTS" output.mp4
The lower the PTS value, the faster the time-lapse video is generated. If you use a larger value, the video will display in slower motion.
PTS值越低，延时视频生成越快。 如果使用较大的值，视频将以慢动作显示。
调整视频和音频 (Adjust video and audio)
If you care to sync the audio speed with the video speed, things get a bit more complicated:
如果您想将音频速度与视频速度同步，事情会变得更加复杂：
ffmpeg -i input.mp4 -filter_complex "[0:v]setpts=0.5*PTS[v];[0:a]atempo=2.0[a]" -map "[v]" -map "[a]" output.mp4
More confusing is that the atempo setting seems to require reverse logic to setpts ; i.e. doubling speed seems to require a different multiple.
更令人困惑的是， atempo设置似乎需要对setpts进行逆向逻辑; 即倍增速度似乎需要不同的倍数。
I recently used this slow-mo technique on a highlights video downloaded from YouTube to draw my own conclusions about a specific play. The ability to manipulate video so easily, without a UI, also makes for easy automation of media, especially when you combine this technique with -- you get just the frames you want at the speed you want. ffmpeg FTW!
最近，我在从YouTube下载的精彩视频中使用了这种慢动作技术，得出了自己对特定游戏的结论。 在没有UI的情况下如此轻松地操作视频的能力也使媒体的自动化变得容易，尤其是当您将此技术与结合使用时-您可以以所需的速度获得所需的帧。 ffmpeg FTW！
翻译自:
ffmpeg视频压缩速度