DATA RATES - what is best?
http://www.communitymx.com/content/article.cfm?page=4&cid=EBD77
They are talking about the old flash, but recommend not setting video data rate to
• Keep the video data rate below 275 kbps.
• Make audio mono and 64kbps unless it sounds shit.
Maybe this is outdated, because at flashcomguru, they refer to 500kbps like this
Encoded at a mere 500bkit/sec this demonstrates just how well the H.264 codec can perform at low bitrates.
So implied is that 500kbps is a low bitrate these days...
I just did Flash 8 High Quality (max rate 700kbps)
This is probably too high... but it looks really really good on my local preview...
but from a site I just read (no date on their posts though;
We use 272kbps/544kbps/1088kbps for low/medium/high quality video respectively.
This sounds sensible.
Heres a cool bitrate CALCULATOR!! the holy grail!!!
so its recommending me for a 460kbps video, that users will need a 600kbps connection.
so i look at my local broadband provider and the plan i am on (ADSL2+) runs at 24,000kbps. They say its 3 times faster than old broadband so guess that was about 8000kbps. So even the old broadband was fast enough by a factor of 10.
What gives? Why worry then? Sure my video is only 320x180
Even if I test the 1024x576 at best quality - it recommends a video br of 3932kbps - or a user connection speed of 4910kbps. Thats a massive video and it still is only a bit over half the old broadband speed. AND this is in Australia where the internet is controlled by dinosaurs and heaps slower than in Europe. There must be some other factor, like file size/hosting download limits, that would make you not want to post up a 4000kbps full screen video. I am seeing now why they were calling 500kbps a low speed above. And Flashes Hi quality default setting is 700kbps. Not that fast it seems
So conclusion is that about 700kbps should be fine/ pretty good looking for a 320x180, maybe even overkill 400 looks pretty ok also.
It seems to get trickier as frame size increases, more tradoffs must be made. 640x360 'action trailer' wants 1500kbps.
On the JW media player forum there is this advice for stuttering video which makes me think not to go over 800kbps uploading to a server with unknown speed (probably cheap /shared hosting). So around 700 I think is good.
Your server delivers at approximately 850kbps.
Your FLV requires approximately 1700kbps (combined video/audio/overhead).
Therefore, the player consumes the media data twice as fast as it is delivered.
Accompanying that - a table of best video frame sizes, apparently for encoders to do the best job, only certain frame sizes should be used, those that are multiples of 16 see the link for the table
Some general settings someone uses for encoding flash video.
adobe about video encoder CS3 custom settings
A WHOLE BLOG about flash, and this link purely on news about flash & video, esp h.264
a flash video encoding wizards website
amazing bit of code adds a video smoothening function - like antialiasing, so its less blocky, especially if its been downsized dramatically.
This is a pretty extensive article to brush up on or learn about flash video in Flash CS3, and video in general too.
massive list of articles on all things video - can search by program, conversion type and so on.
New full screen mode available in fp9 link to keep.
Video encoder settings comparison testsuite - many setting to choose from -
here a ppt presso with main steps of encoding but not the details
Heres a good walkthough of encoding issues and flash video encoder. It was written in 2006 so I think their talk of 400kbps being too high is a bit dated.
OK so starting now to develop a video encoding checklist i wonder if any else has one. It would include
deinterlacing
resizing video only to a multiple of 16
keeping the correct aspect ratio when resizing
adding smoothening script in flash
proper bitrate/fps/keyframe spacing for the type of footage
starting with best possible quality file using a non lossy codec (eg animation codec)
use on2vp6 or h.264 if your future minded
theres also some thing you need to do to h.264 quicktimes to make them 'fast start'. the fast start option box should always be ticked when its available and your doing internet videos.
http://renaun.com/blog/2007/08/22/234/also just read somewhere that using the smoothening script in flash can be too much for older computers, they arent fast enough or something, can make the video play jumpy.
This from adobe flash video encoder cs3 help
If a video clip is longer than 10 minutes, the audio will drift noticeably out of sync if you do not adhere to the 29.97 fps rate or an accurate even division for lower frame rates (such as 14.98 fps, which is half of 29.97).
If your video clip is encoded with a higher data rate, a lower frame rate can improve playback on lower-end computers. For example, if you are compressing a talking-head video clip with little motion, cutting the frame rate in half might save only 20% of the data rate. However, if you are compressing high-motion video, reducing the frame rate has a much greater effect on the data rate.
Alternative Encoders
To get the best encoding - 2 pass VBR encoding is the way to go. Flash CS3 encoder apparently dosn't do 2 pass encoding. im guessing that this means the other encoders will be much better with fast movement.
If I was doing alot of this sort of thing, the Flix Pro looks great, and they have a whole package that includes players to output to, so it could be a neat end to end thing, better encoding and better players.
Good article but dated on the differences of the 3rd party encoders. Sorrenson has a better batcher but this was written in 2006 flix might be better now.
http://www.adobe.com/devnet/flash/articles/selecting_video_encoder_02.html
And heres a comparison page that will show you the difference between the 3 main encoders, Flash Video Encoder, Sorrenson Squeeze, and Flix Pro. It is down at the moment though.
http://www.flashvideofaq.com/
Flix Pro $249
http://www.on2.com/index.php?365
* Two pass encoding
* On2 VP6-S for High Definition (HD) output
* Hollywood-like "green screen" special effects
* Cool usability features, such as cue points and batch encoding
* Automatically output Flash Players for your video
* Output an HTML page to play your video with a click of the mouse
Sorrenson Squeeze
The other good one, has a cool feature called 'watch folder' where it encodes anything you put into a folder without opening the batch window. I can imagine this as a really satisfying feature. It offers 2:1 and 3:1 frame rates so it automatically does your frame rate for you at logical settings for lowering the frame rate.
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