YouTube - MPEG4 (Divx, Xvid)?


New member
Interesting. I had read in Creative Cow magazine that uploading in the native flash format was best. That way YouTube didn't recompress.
I think you are best off exporting your final product from a third-party app.

Here is an exerpt from Aharon Rabinowitz's article on "How to Preserve Detail in Mini-Media Movies" from Creative Cow magazine ( publisher) March/April 2007.

What YouTube doesn’t tell you is
that if upload FLV files under 100 MB
as well, they don’t recompress them
when uploaded to their server!
I should mention that this only
works with Flash 7’s Sorenson Spark
Codec, not the newer Flash 8 VP6
codec. Regardless, it means that you
can upload a FLV whose quality you
control, and YouTube won’t touch it.
There’s a delicate balance between
video quality and download
size but, if you can find that balance,
your videos will look better on You-
Tube using Flash than any other format.


We've got it simple.
I have heard the same about YouTube not recompressing flash files.

But honestly, imo, I don't believe it.

What I have read basically says if you get the right combo of Flash codecs happening YouTube leaves the file alone.

But think about that for a second.
That would mean we (you,me, them Everybody, EVERYBODY) could upload a 5 second movie at whatever astronomical bitrate it took to make sure it is no larger than 99.9megs and as long as it is in the right Flash codecs YouTube won't touch it? I don't know, not even Google has the money for that kind of wasted filespace and bandwidth. Storage would get out of hand.

Once word got out why would anyone encode their files at a bitrate that didn't give them anything but a 100meg file?
Soon YouTube servers would be FULL of 100 gig files and nothing else.
5 sec vid, 100 gigs, 10min vid 100gigs

Not to mention the fact that a bitrate that high is gonna choke any net connection and play poorly... reflecting on YouTube's quality.

I believe youTube recompresses EVERYTHING for 2 simple reasons.
1-To make sure everything streams and plays properly. According to the standard they set.
2-To control file space and not let people get out of hand with file sizes.

Anyway.. bla bla bla .. one man's stinky opinion.

To actually answer your question Tom. fwiw, I send them a 99.9 gig 320x240 file for everything, using whatever is the best codec I can use and make it fit.

Since YouTube is going to squash it to aprox 350Mb/s anyway, and throw away the original (imo) I make sure to give them the BEST source to start with.
If it is a short piece and I can use uncompressed avi, I do, sometimes DV Type2, sometimes big mpeg4. The important thing for me is not the codec but supplying the best quality 99.9 meg file.
I try not to send them wmv's or flv's or swf's or anything that has already had a lot of compression.


Tom Wood

Thanks guys,

I've been doing more research and found this site:

Here's a recap:

1. Use H.264 codec, the best MPEG4 codec in the market today.

2. Set Quality to Best.

3. Set rate control to 1-pass Constant Bit Rate (CBR). So no Variable Bit Rate, no Multipass. YouTube transcoders prefer CBR.

4. Set key frames to every 30 frames or less. The more key frames the more information your video will have. YouTube transcoders loves keyframes. I usually set key frames every 15 frames in my high motion videos, however keep an eye on the file size.

5. Set data rate to 1000 kbps or more, depending on the running length of your video. By default I use 2000 kbps in my short videos. Again keep an eye on the file size.

6. Set aspect ratio to 320x240. You do not want YouTube to resize your video using a bicubic, bilenear or substandard method. Chances are your compression software uses a better algorithm. For widescreen videos set frame size to 320x180 pixels.

7. Set frame rate to 30 fps.

8. Set audio compression to MP3 or AAC: 44.1 KHz, 64 kbps, 16 bits, monophonic.

9. De-interlace your NTSC or PAL source videos, especially if it's high motion

10. Apply filters to improve the look of your video: a bright/contrast filter and/or an image sharpening filter.

I didn't realize H.264 -is- MPEG4, so that helps. I can get pretty good results using QuicktimePro with this if I experiment with the number of keyframes and the data rate. You can set the keyframes then increase the data rate until the file size no longer increases, so that's a clue. I don't understand why the YouTube encoders would care what data rate you use if they are compressing it to 350 kbps anyway.

I had to get rid of my motion background and the text crawl across the bottom of the screen to get the animation itself to look decent. It's my understanding that they are still using Flash 7 vintage codecs to maintain playability across the network. Which is a real shame since Flash 8 came with the ON2 codec and it looks great.

Tom Wood

Dang timeout....

I've been experimenting with just a 20 second file. All my stuff is CGI starting with uncompressed TGA image sequences, then uncompressed RTV files. My workflow is LightWave>Mirage>VT4 where I render out using the uncompressed Apple Animation codec. But that file is almost 2 GIGAbytes so I have to recompress using QuicktimePro. I can drive the filesize up by increasing both the number of keyframes (all the way to all) and/or the data rate.

But when YouTube gets ahold of it, it doesn't seem to matter how big the file is. The detail is there, but there's a lot of temporary blocking artifacts that come and go, telling me that it couldn't handle all the data I'm feeding it. I think I'm going to try -fewer- keyframes to free up some bandwidth since I really don't need it to re-encode the background still very often, which is where more keyframes would add unnecessary encoding.


New member
Actually, it WAS correct. Apparently YouTube has recently changed that. Here is further info from Aharon (Take it how you want):

So, it appears YouTube Caught on to the tests that I and many others were doing to find the best FLV settings for YouTube.

Up until recently, you were able to upload FLV's to You Tube without them messing with (i.e., compressing) your videos. Alas, they decided to change that. It's too bad too because you were able to get some really high-Qulaity video on line. Now they convert Flash FLV's too.

Here are some samples of tests I did before it got shut down - hit more info by each video to see the settings I used:

Medium Quality:

High Quality:

Super High Quality:

Anyway, with that out of commision, I found that WMV's did pretty well when uploaded and converted - especially compared to MOV's which not only looked bad, but also suffered from A/V synch issues.

Aharon Rabinowitz


Jim_C said:
I have heard the same about YouTube not recompressing flash files.

But honestly, imo, I don't believe it.



We've got it simple.
Thanks Perch...

It did seem like a 'too good to be true' thing. And I guess now, it is.


Paintball Video Geek
YouTube is converting everything to H.264 - so something today uploaded in Flash, is eventually going to be converted by them. It has to do with making the whole YouTube library playable on AppleTVs.

Moody said that YouTube will soon be encoding videos in the H.264 streaming-efficient compression format preferred by Apple TV, and that all new videos submitted to YouTube as of the mid-June launch of the AppleTV update will be playable by the device. From then until fall, YouTube will be encoding its entire back-catalog in H.264 format, adding videos in chunks until everything is accessible to Apple TV users.

Tom Wood

I guess I'm confuzzled then. If you right-click on any new embedded YouTube player window it says it's a Flash 9 player. Is it playing a Flash FLV or a H.264 MOV file, or possibly either one?


New member
Full Rez SD Dv25 Quicktime

I used to upload all my stuff to UTube in .M4v or Mpeg4
But since they upped the cap to 2GB, I can upload 10 min videos in full "uncompressed" native dv. (I know dv is compressed 5-1)

I get excellent results that way. It helps to have OC3 here at work.


We've got it simple.
Youtube now supports 4k

Friday, July 9, 2010
What's bigger than 1080p? 4K video comes to YouTube

Today at the VidCon 2010 conference, we announced support for videos shot in 4K, meaning that now we support original video resolution from 360p all the way up to 4K. To give some perspective on the size of 4K, the ideal screen size for a 4K video is 25 feet; IMAX movies are projected through two 2k resolution projectors.



We've got it simple.
Ohh and youtube also fairly quietly increased their max video time to 15 minutes.
(which means you can sneak in 15:59 mins)

Thursday, July 29, 2010
Upload limit increases to 15 minutes for all users

We want YouTube to be the best place to upload video. Without question, the number one requested feature by our creators is to upload videos longer than 10 minutes. We’ve heard you, and today we’re pleased to announce that we’ve increased the upload limit to 15 minutes.

I still like Vimeo better. Doesn't make me feel so dirty after using it.
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