Web delivery resolutions

J

jeffyjones

Well-known member
What are the proper resolutions to encode for Web delivery? For the true 16:9 cuts on Apple's HD trailer site, none of them are what I'd expect (i.e., 1920x1080 for 1080p, 1280x720 for 720p, 853x480 for 480p).

I know that I can choose to compress to these resolutions, but I'm curious to know what the reasons might be for the odd resolutions they use.
 
The trailers are cropped to their theatrical aspect ratio (1:1.85, 1:2:35 etc.)
1920x1080 and 1280x720 are both 1:1.77 (16x9)
Instead of letterboxing the trailers they are simply cropped in the vertical axis.
 
I do understand about the aspect ratios on some of them with the wider format, but for example, Ice Age 2 at 48op is 848x448, which comes out to 1:1.89.

But I guess what you're saying is that if I shoot in 720p then it's appropriate to compress to 1280x720 as the standard, yes? Back in the bad old days, we had various sizes that we typically compressed video to, the biggest of which was generally 360x240, plus the goofy numbers that Windows Media used (I believe because of optimal compression based on certain sampling block sizes).
 
320x240 actually, you have to account for square pixels. And that's still a very common size online. I do video for online training courses much of the time, and it's usually 400x300 (or 400x224 for 16:9) at around 400Kb/s. 600x336 is a pretty good "large" 16x9 size at around 1Mb/s. There is no "standard," it's whatever works within your web page design, and at the lowest common denominator codec for your particular audience. I encode to Flash (Spark) most of the time for this reason, even though I have all the new stuff.
 
Oh, yess indeed you'd want to offer different versions for a few connection speeds.
Most codecs generally want a multiple of 8 because of the macroblock size, but then again most codecs today will automatically pad the image with invisible pixels to fit the macro block size.
All Apples movie trailer are progressive downloads, meaning that it won't try to stream, so any connection speed will do, it just depends on how long the user will wait.
With H264 you can compress larger framesizes then ever bofore, but some users might be at a slow connection with an old computer.
 
Yeah, I meant 320x240. Gotta lay off the crack here. ;-)

Back in the day I used to do a lot of encoding to Sorenson 3, which frankly seems to be passe now. Although that might be justified because in some of my initial tests it doesn't do that well with larger formats. You need obscene data rates to get the same quality you can get out of H.264.
 
jeffyjones said:
Yeah, I meant 320x240. Gotta lay off the crack here. ;-)

Back in the day I used to do a lot of encoding to Sorenson 3, which frankly seems to be passe now. Although that might be justified because in some of my initial tests it doesn't do that well with larger formats. You need obscene data rates to get the same quality you can get out of H.264.
Click to expand...


Not true. I used Sorensen squeeze to get this clip down to size:
http://jsgraphics.tv/dvxuser/distillery2HD_720_Hi001.mov
The H264 was twice the size at comparable quality.
 
If you want an MOV and are unsure if you're audience has QT7 (many do not), Sorenson3 is still your best bet I think. I personally use SWFs most of the time because Flash has the most browser compatibility. But if you're only sharing it with other professionals, most folks are gonna have the latest codecs.
 
i would agree that sorenson 3 has probably the best quality/size to widespread use ratio.. there are still a lot of people who don't even have mp4 capability, much less the h264 variety.

lately i've been putting up an h264 version along with a sorenson 3 version... good idea on the swf option. hadn't thought of that. but anything to avoid wmv....
 
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