MP4 quality


I'm just curious.

I have a number of music video downloads from YouTube that I have converted to MP4 format. I always set the conversion settings from flash to MP4 at 'High Quality'. Yet many of my MP4 files are degrading over time, i.e. they convert well with high quality definition immediately after conversion but then a few months later the quality deteriorates.

Is this normal?


What app are you using to _play_ those mp4s?

I doubt that the file itself is changing, but can you test that?
Find a file that has apparently deteriorated.
Then, find the same video on the 'net, and convert it now. Does it play at the same quality that you expect? Then, play the old video that you think has changed over time. Is it still worse than the new conversion of the exact same music video?
Is the change only in the audio? or, both audio and video have changed in quality? Or, something else?
Is there a difference using another vid player, such as comparing VLC to your QuickTime player? Or do you use other players?