HELP: Compressing Video

Now I am in such a bind. I have been trying to compress a 20 minute, 1920x720 20gig video file so it is 853x480 and only about 300-500 megs, like apple does for their movies.
How do they do it? I can only get it down to about 2 gigs and it still looks good. Below that and it begins to look pixelated.

Apple gets a whole movie down to 1.5 gigs.

Thank you

...for an hour and a half feature you could use H.264 VBR 2 pass (or 3 pass on X264) at a target data-rate of about 1.5Mbps up to 2.40Mbps .

Or use 1280x720p @1.5Mbps to 2Mbps for iPad/Pod/Phone/AppleTV - should look good and be about 900MB to 1.2GB for an hour and a half. Twenty mins will come out around 280MB

You basically have a maximum of about 14Mbps (video and audio data-rate added together) to play with if you want a 20 min film to be >2GB.

This is a huge amount for 853x480 if using the H.264 codec; where 2Mbps Video plus 128Kbps AAC Stereo audio would do adequately and anything over 5Mbps would probably be wasted on this resolution (at least for most purposes).

Get yourself Bitrate Pro: [www.apple.com] or some other data-rate calculator which will help you decide what rates to encode at, given at least 2 of the variables: duration, file-size and data-rate.



For instant answers to more than one hundred common FCP questions, check out the LAFCPUG FAQ Wiki here : [www.lafcpug.org]

1920x720?

???

Sure you don't mean 1920x1080, or 1280x720? Because if your source frame size really is 1920x720 (2.66:1???), then 853x480 (16:9, the standard HDTV aspect ratio) would give you the wrong aspect ratio.

Twenty minutes isn't too bad, and the small-ish 853x480 frame size actually gives you breathing space. But you have to pick the right wrapper, the right codec, and the right bit rate. Also sacrifice a bit of data rate on the audio; it will make more difference in the picture. Try MPEG-4 in H.264 codec, 3000-5000 kbps. (You can try higher than 5000kbps, but in my own experience, that's usually around the threshold when people start having problems streaming the clip, even after YouTube's Flash compression)

If picture quality is your concern over the amount of time it takes to compress, then in whatever software you're using (Compressor? MPEG Streamclip? Sorenson Squeeze?), activate the multi-pass and b-frame options.

People always say, "Apple gets this great quality for this little file size". Well, the studios pay professional rates at professional facilities to get those results. Do you seriously think you can get the same results with your $10,000 computer/software as a $50 million production can?


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