The format/codec you choose does have an impact on quality, since the better looking your file is, the better the encoded YouTube file will be.
Unfortunately, there isn't much you can do regarding smooth playback, as no matter which format/codec you use, they will re-encode it anyway.
Of course, HD and the HQ setting are tougher. So, you may warn your viewers to disable the HQ mode if they're having playback problems.
Thank you for the Reply,
Since YouTube is going to re-compress the file, does that mean I should send them the least compressed video that I can up to their maximum file size limitations of 1 Gig, meaning: I should not lower my data rate and/or frame size, key frames settings etc.... Or do I try to send them the smallest best looking video that I can and therefore they will do less compressing of it.
1 person found this helpful
An H264 file at standard defintion sizes and a bitrate of about 3 Mbps should work very, very well as a source for YouTube.
Yes, you could produce the largest file they let you upload, but it's also true that pristine quality is really not their main concern for encoding, so you could spend your life uploading gigantic files and get modest improvements in quality.
If quality is your main concern, I'd take a look at Vimeo.
Since YouTube is so popular, you may prefer the trade-off. In any case, uploading an H264 file with specs similar to those I described above should work fine. Using 2 pass VBR encoding in AME standalone can help in getting the most out of the bitrate.