ffmpeg 將 wmv 轉檔為 mp4 for iPad

不囉嗦，以ffmpeg轉檔的範例如下：

ffmpeg.exe -i [INPUT_FILENAME] -vcodec libx264 -r 30 -ar 44100 -async 1 -f mp4 -b 2M -bt 4M -pass 1 -r 30000/1001 [OUTPUT_FILENAME]

-f mp4 : input or output format.
-r 30 : 30 frames/sec
-ar 44100 :  audio sampling frequency : 44.1kHz
-async 1 : Audio sync method. -async 1 is a special case where only the start of the audio stream is corrected without any later correction.


延伸閱讀：官網 ffmpeg Documentation