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jmartis
Hello, would someone advise the best format/video encoder for uploading videos to youtube? I now use DivX 320x240 (30fps or less) (usually 200-300kbps) and mp3 32kbps, and I often notice that my uploaded videos are lower quality and load much slower than some other ones. What is the trick?
smok3
they will get transcoded to flv, so upload the best you can.
jmartis
QUOTE(smok3 @ Aug 18 2007, 22:06) *

they will get transcoded to flv, so upload the best you can.

OK, but why some load faster than others then? I tried uploading the same vid with different bitrates/formats, and this had effect on the loading time (higher bitrate>slower loading)
smok3
QUOTE(jmartis @ Aug 18 2007, 22:27) *

QUOTE(smok3 @ Aug 18 2007, 22:06) *

they will get transcoded to flv, so upload the best you can.

OK, but why some load faster than others then? I tried uploading the same vid with different bitrates/formats, and this had effect on the loading time (higher bitrate>slower loading)

that would either mean iam wrong or you are smile.gif
hushypushy
My Youtube vids are DV sourced; I encode them to Xvid 640x480, ~1500kbps and LAME MP3 @ 128kbps CBR, usually, and IMO my videos look pretty good (just ask if you want to look).

I heard that 320x240 looks better because that's what it resizes to--I tried that with my latest video and the results were very disappointing. I'm going to stick to 640x480.

Are FLV files VBR encoded? That might explain a download difference...if FLV is assigning less bits, it will be a smaller file, thus a faster download. Just a thought.
smok3
yes they could be VBR encoded, but the difference should be small, unless they do some sort of quality based encoding (unlikely), well i guess someone will have to rip some and do some comparison, like this one maybe:
http://somestuff.org/downloads/apple_trail...pple_ales.xhtml (which i did for apple trailers)

(mediainfo_gui + notepad ++ + open office calc)
Dynamic
Just a thought, but perhaps frame rate varies? Halving to 15 fps (or 12.5 fps for PAL or SECAM sources, or 12 fps for movie reels) might provide acceptable results with faster downloads. Also, mono sound might improve things, though I have a feeling Flash video might choke on mono, like it chokes on anything other than 44.1 kHz sampling rate.
smok3
you think? i belive they figured out about 100 years ago that one would need at least 24 fps for smooth motion, i dont see how 'internet' should change that? (basically: if you can not provide proper framerate, just don't do it...)
Synthetic Soul
Most sites have a FAQ or help section...

http://www.google.com/support/youtube/bin/...py?answer=55745
Dynamic
All I mean is there are certain types of content where low frame rate is acceptable. It might be how some people have forced lower bitrates out of a transcoder they don't have control over.

If it is VBR, it's conceivable that gentle blurring to reduce the highest spatial frequencies or temporal smoothing in VirtualDub could improve the quality/bitrate tradeoff. But when you don't have access to the FLV encoder on YouTube you simply have to try things to see what might work
smok3
Dynamic, maybe, do you have a link?

(from 3 random clips i ripped two are 29.x fps and one is 24 fps, they all look like cr@p thought...)

anyway, with some proper bitrates and codec like VP6 you can get almost decent results using FLV, example:
http://blog.somestuff.org/index.php?entry=entry070821-044200
so, blame youtube for eveything wink.gif
milatchi
QUOTE(smok3 @ Aug 18 2007, 12:06) *

they will get transcoded to flv, so upload the best you can.

Words I live by.
smok3
turns out there is a hack to be used to get online 1:1:
http://forum.doom9.org/showthread.php?t=129982
smile.gif

(but don't expect this to work for any longer amount of time...)
F J Walter
You should upload in the best possible format they accept for uploads, at the highest bitrate you can manage given their limitation on upload size.

They'll transcode it to flash video at around 300kb/s at 320x240, no matter what format you use. Which means you really need your input video to be _significantly_ better quality than that when you upload to them.

Try sending them H.264 or MPEG-4 ASP video at 320x240 at at least 600kb/s video bitrate, with AAC audio at least 128kb/s bitrate (stereo, or 64kb/s mono).

A bit of noise reduction may help too, in theory, because there is no way of altering the way YouTube's transcoder encodes things and they have pretty fixed rate control.

Also keep in mind that in the future, YouTube may support higher quality video, and they may re-encode their existing videos to a better quality format (presumably from the source you uploaded?). They have already announced that they are re-encoding their videos in H.264, initially just for AppleTV users.

hushypushy
Interesting thread: http://forum.videohelp.com/topic336882.html
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