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flumpdumpy · 29th June 2005, 15:46

I've been toying around with backing up some HD content that I have captured. and I noticed something interesting about 720p streams. Most of this is common knowledge so please forgive me for going over rudimentary stuff here, I'll get the point as quickly as possible.
The majority of HD programming other than sports, is filmed on movie-type cameras that record at 24fps. When a show is then broadcast in 1080i it uses the same pulldown method that DVD's use to change to 29.97fps. When a show is broadcast in 720p, it uses a similar method to get to 59.94fps. The difference though, is that with a progressive input and progressive output, whole frames are repeated, not fields.
Getting 720p show back down to it's original 23.976fps is no problem. But since I am going to have to re-encode anyway, I'd like to make the video stream as compliant as possible so I won't have to re-encode again when recordable HD-DVD's or Blu-Ray come out.
I originally thought, "Hey, no problem, I'll use the custom setting in DGpulldown and set it to 23.976->59.94". But then I got to thinking, is this really going to give me what I need. So here is the question:
If I use the custom setting to go from 23.976 to 59.94, will it achieve this by repeating whole-frames or fields. Because if it uses fields, that will likely thrash the video output.

29th June 2005, 15:46	#400 \| Link
flumpdumpy Registered User Join Date: Feb 2004 Posts: 6	A question about HD content. I've been toying around with backing up some HD content that I have captured. and I noticed something interesting about 720p streams. Most of this is common knowledge so please forgive me for going over rudimentary stuff here, I'll get the point as quickly as possible. The majority of HD programming other than sports, is filmed on movie-type cameras that record at 24fps. When a show is then broadcast in 1080i it uses the same pulldown method that DVD's use to change to 29.97fps. When a show is broadcast in 720p, it uses a similar method to get to 59.94fps. The difference though, is that with a progressive input and progressive output, whole frames are repeated, not fields. Getting 720p show back down to it's original 23.976fps is no problem. But since I am going to have to re-encode anyway, I'd like to make the video stream as compliant as possible so I won't have to re-encode again when recordable HD-DVD's or Blu-Ray come out. I originally thought, "Hey, no problem, I'll use the custom setting in DGpulldown and set it to 23.976->59.94". But then I got to thinking, is this really going to give me what I need. So here is the question: If I use the custom setting to go from 23.976 to 59.94, will it achieve this by repeating whole-frames or fields. Because if it uses fields, that will likely thrash the video output.