HDV tape should = 1 gb/minute or so BUT...help

[bluntforcetrauma]

I have taped using HV30 and hdv tape for a 52 minute shot. When i capture to imovie it says the file is only 38gb, am i missing something?

I thought it should be closer to 52 gb. Almost a full tape?

please advise

I am filming in HDV30p--I always have but it just seems that the size is smaller.

could i have changed something without knowing it?

thanks in advance

[Barry_Green]

A full HDV tape should take up about 13GB. Is iMovie transcoding to AIC or something?

[toolmodel]

Every tape I digitize through PP CS3 that I shoot on my XH-A1 takes up about 10GB/hour. Keep in mind that HDV has a bitrate of 25Mbps which translates to 3.125 MB per second meaning a tape should make up 11,250MB over an hour or 10.98GB

[bluntforcetrauma]

A full HDV tape should take up about 13GB. Is iMovie transcoding to AIC or something?


yes it is transcoding to AIC.

What exactly is AIC --i know its an apple codec--but again what does that mean and how come when one hdvp30 60 minute tape equals about 60gb on the Hard drive thru imovie.

I dont even know enough to spell dangerous

thanks in advance

[Huy Vu]

AIC=Apple Intermediate Codec. It's taking the interframe HDV footage and making it into intraframe editing codec with a Quicktime wrapper for faster preview and editing. The upshot of this is the data rate more than tripled, which is why you're getting larger file sizes.

[ef03]

But making the data rate higher on capture won't improve quality of your footage. If you capture an HDV file then convert it to full resolution 1080 at 10 bit sampling you will have a huge file that looks exactly the same as the original.