A 4 min 1080p30fps video taken with my phone camera is 518MB, While a 12 min 1080p30fps video ripped from youtube is 341MB, both are using mp4 h.264 as codec and the youtube one isnt of lower quality, so why this big difference?

  • Resolution and quality are different things, especially when different codecs are used for data compression. An AVI i record for acreen capture might hit 250 MB, running that through ffmpeg to get an mp4 might be 20MB, if i drop the quality but same resolution then sometimes 7MB