PROSAGA码农传奇-ffmpeg-FFmpeg：如何有效地分割视频？

ffmpeg wiki参考“如何有效地分割视频”链接回到此页面。我不相信此页面会回答该问题，所以我按照@AlcubierreDrive的建议进行了操作…

```
echo "Two commands" 
time ffmpeg -v quiet -y -i input.ts -vcodec copy -acodec copy -ss 00:00:00 -t 00:30:00 -sn test1.mkv
time ffmpeg -v quiet -y -i input.ts -vcodec copy -acodec copy -ss 00:30:00 -t 01:00:00 -sn test2.mkv
echo "One command" 
time ffmpeg -v quiet -y -i input.ts -vcodec copy -acodec copy -ss 00:00:00 -t 00:30:00 \
  -sn test3.mkv -vcodec copy -acodec copy -ss 00:30:00 -t 01:00:00 -sn test4.mkv
```

哪个输出...

```
Two commands
real    0m16.201s
user    0m1.830s
sys 0m1.301s

real    0m43.621s
user    0m4.943s
sys 0m2.908s

One command
real    0m59.410s
user    0m5.577s
sys 0m3.939s
```

经过几次运行和一些数学运算后，我测试了SD和HD文件。

```
Two commands SD 0m53.94 #2 wins  
One command  SD 0m49.63

Two commands SD 0m55.00  
One command  SD 0m52.26 #1 wins

Two commands SD 0m58.60 #2 wins  
One command  SD 0m58.61

Two commands SD 0m54.60  
One command  SD 0m50.51 #1 wins

Two commands SD 0m53.94  
One command  SD 0m49.63 #1 wins

Two commands SD 0m55.00  
One command  SD 0m52.26 #1 wins

Two commands SD 0m58.71  
One command  SD 0m58.61 #1 wins

Two commands SD 0m54.63  
One command  SD 0m50.51 #1 wins

Two commands SD 1m6.67s #2 wins  
One command  SD 1m20.18

Two commands SD 1m7.67  
One command  SD 1m6.72 #1 wins

Two commands SD 1m4.92  
One command  SD 1m2.24 #1 wins

Two commands SD 1m1.73  
One command  SD 0m59.72 #1 wins

Two commands HD 4m23.20  
One command  HD 3m40.02 #1 wins

Two commands SD 1m1.30  
One command  SD 0m59.59 #1 wins

Two commands HD 3m47.89  
One command  HD 3m29.59 #1 wins

Two commands SD 0m59.82  
One command  SD 0m59.41 #1 wins

Two commands HD 3m51.18  
One command  HD 3m30.79 #1 wins  
SD文件 = 1.35GB DVB传输流
HD文件 = 3.14GB DVB传输流
```

结论
如果要处理HD，单个命令会更好，它与输入文件后使用-ss进行“慢速搜索”时的手册注释相符。SD文件的差异可以忽略不计。

通过在输入文件前添加另一个-ss来进行“快速搜索”，再执行更准确的慢速搜索，这两个命令版本应该更快。