See FFmpeg Wiki: H.264 Video Encoding Guide for more info. Notesĭefault encoder for MP4 is libx264 (H.264 video) or mpeg4 (MPEG-4 Part 2 video) depending on your ffmpeg build. This way you can experiment and adjust your cropping without the need to encode, view, repeat. You can take a crop (heh heh) and preview it live with ffplay: ffplay -i input -vf 'crop=in_w:in_h-40' The filter will automatically center the crop if x and y are omitted such as in this example.The output width and height can also be used with out_w and out_h.Ĭrop 20 pixels from the top, and 20 from the bottom: ffmpeg -i in.mp4 -filter:v 'crop=in_w:in_h-40' -c:a copy out.mp4

You can refer to the input image size with in_w and in_h as shown in this first example.To crop the bottom right quarter: ffmpeg -i in.mp4 -filter:v 'crop=in_w/2:in_h/2:in_w/2:in_h/2' -c:a copy out.mp4 The audio is stream copied in this example, so re-encoding is avoided.x and y specify the top left corner of the output rectangle.out_h is the height of the output rectangle.out_w is the width of the output rectangle.

Use the crop filter: ffmpeg -i in.mp4 -filter:v 'crop=out_w:out_h:x:y' out.mp4

Ffmpeg crop novie