I had rendered my previous video for Vimeo, but Vimeo for unresponsive at the time, so I uploaded it to Youtube. Then I uploaded a second video to Youtbe, rendered with the Youtube settings.

As far as I can tell, rendering with the Vimeo profile give far better results, because the bitrate is higher. So why is the Youtube profile set with such a small bitrate? (both profiles used were single pass)

I did not write these render profiles and I am just guessing here. At one point YouTube had more limited upload sizes and recommendations. Maybe the profile is old. YouTube now accepts very large sizes, and its HD output is quite nice for web video.

YouTube recommend "you may get the best uploading results from converting your file to MPEG4 video with MP3 audio" - http://www.google.com/support/youtube/bin/answer.py?answer=55744

For the sound, use 44100 Hz instead of 48000 - http://www.google.com/support/youtube/bin/answer.py?hl=en-uk&answer=132460

I've tried the following with acceptable results : AVI, 1280x720, framerate as per original clips (YouTube preserves this, allowing 25 or 30 fps for example - and so do Vimeo), with Encoder Options as follows: MPEG4 with average/max bitrate 9000, sound: MP3, 44100, 320 kbps, stereo.

I have also found that if I convert AVCHD Lite mts files in NCH's Prism converter (because they don't work 100% well in my NLE otherwise) it's best to select [Options]... [Conversions]... and tick the box to use FFMPEG. Otherwise it looks shoddy. YouTube do say "it is recommended that you use FFMPEG" (see first link above).

Vimeo's current advice is at http://www.vimeo.com/help/compression

Thanks. I think we will modify Kdenlive default profiles accordingly.

The Youtube profiles have a typo in latest SVN, 41100 for audio instead of 44100

thnks, I just fixed it.

I guess another addition will be needed as of next week. Youtube will go 1080p!

1080p? Hmmm. At this point, even with 720p online eg Youtube or Vimeo, the limiting factor is the Flash player. I don't know of any way you can get decent playback of HD on Linux with Flash at this point.

There is a new beta Flash player Adobe just released. The big thing is h264 acceleration through a video card. I tried it out yesterday on a Vista machine, it's a revelation. 720p with no stuttering. This makes web video for the first time functionally as good as TV. (Well, not quite, but very very watchable whereas before you were always aware that this was substandard internet video.)

Unfortunately the Linux version has NO acceleration and there is no 64 bit update. Arghhh.

Gnash has some work with Flash acceleration in the gnash-vaapi experiments, sure hope this gets stabilized and released soon.

I fully agree with you, but the majority of my Youtube viewers use Windows, therefore I see it as progress. Flash on Linux is a pain in the ****, I know, but I also have great experience with South Park's online player in it's HD mode, so it isn't all bad.

But Flash video on netbook, mobile, and embedded Linux is going to be awesome according to the release notes of the 10.1 beta! Oh well, so much for the desktop.