View Full Version : WMV VC-1 720p eats twice the filesize as original HD Mpeg?


Lars Siden
October 17th, 2007, 05:54 AM
Hi guys,

I have a Canon HV-20 that I use to film in 1080i. For fun I converted a short movie to Microsoft VC-1 720p. And if my calculations are correct, VC-1 720p uses 23gb/hour and the original MPEG is about 12gb/hour.

My goal is to save 720p material to my HTPC - preferably without having 10 TB storage :-) I'm also looking at H264 and DivX.

What would you choose in my position?

// Lazze

Kevin Shaw
October 17th, 2007, 08:04 AM
Do you have control over the bit rate being used to encode the VC1 files, and if so what bit rate are you using? VC1 720p only needs ~6-8 Mbps for decent quality, compared to 25 Mbps used by HDV 1080i as recorded by your camera. So your rendered VC1 files should be about 1/3 the size of the original HDV material, not twice as big.

By the way, when calculating your file sizes remember that 1 megabit/second (Mbps) = 0.125 megabytes/second (MB/s), because 8 bits = 1 byte.

Mike Ripberger
October 24th, 2007, 12:10 PM
I would agree with everything Kevin stated, the file size should be much smaller. Check the bit rate.

I do know that most TV broadcasters using these new codecs (most are in Europe) will not go less than 7Mb -8Mb per second as HD tends to fall apart at less than that.

VC1 and H.264 are pretty similar, but I believe h.264 is going to be much more popular in the long run. I would use that...