Hi NMGLUG folks,

I'd like to learn about the quality of different video formats. There is nothing critical about this topic for me. I'm just curious to learn.

For my purposes, and what I'm asking about in this email, I'm ignoring audio. So, when I'm referring to video, it might as well be a silent video. I'm wondering about video quality only.

1 I heard in general that .mp4 files have a higher quality than .web files, but I don't know why. Can anyone explain this to me?

2 If two videos have the same resolution, such as 1920x1080, do these two videos have the same quality? It makes sense to me that the quality is the same. Am I missing something?

3 Here are some specs of 2 formats of the same video

248          webm       1920x1080  DASH video 2646k , webm_dash container, vp9, 30fps, video only
137          mp4        1920x1080  DASH video 4331k , mp4_dash container, avc1.64001e, 30fps, video only

When my command included an option for bestvideo, the result was the mp4 video. I'm not sure why. I'm guessing it was the larger filesize. Being that the resolutions are the same, what extra info is included in the larger filesize? The only other difference is vp9 vs avc1.64001e. I have no clue what the difference is between those two.

Thanks,

LeRoy