ffmpeg to mp4 code example

Example 1: ffmpeg video to mp3

ffmpeg -i "file.mkv" -vn -ar 44100 -ac 2 -ab 128k -f mp3 "file.mp3"

Example 2: ffmpeg webm to mp4

ffmpeg -i "01 - file.webm" -crf 23 "file.mp4"

Example 3: mp4 to ffmpeg

#MP4 - 1080p:
ffmpeg -i input.mov -preset slow -codec:a libfdk_aac -b:a 128k -codec:v libx264 -pix_fmt yuv420p -b:v 4500k -minrate 4500k -maxrate 9000k -bufsize 9000k -vf scale=-1:1080 output.mp4

#MP4 - 720p:
ffmpeg -i input.mov -preset slow -codec:a libfdk_aac -b:a 128k -codec:v libx264 -pix_fmt yuv420p -b:v 2500k -minrate 1500k -maxrate 4000k -bufsize 5000k -vf scale=-1:720 output.mp4

#MP4 - 480p:
ffmpeg -i input.mov -preset slow -codec:a libfdk_aac -b:a 128k -codec:v libx264 -pix_fmt yuv420p -b:v 1000k -minrate 500k -maxrate 2000k -bufsize 2000k -vf scale=854:480 output.mp4

#MP4 - 360p:
ffmpeg -i input.mov -preset slow -codec:a libfdk_aac -b:a 128k -codec:v libx264 -pix_fmt yuv420p -b:v 750k -minrate 400k -maxrate 1000k -bufsize 1500k -vf scale=-1:360 output.mp4

Example 4: how to transcode a video in python using ffmpeg

ffmpeg -i input.mkv -c:a copy -s hd720 output.mkv
This modifies the video to 1280x720 in the output, but you can set the width and height manually if you want:

ffmpeg -i input.mkv -c:a copy -s 1280x720 output.mkv
This produces the exact same output as the earlier command. If you want to set custom sizes in FFmpeg, please remember that the width parameter (1280) comes before height (720).