Greetings.

A week or two ago I stumbled onto a short Tutorial/Tip -- I believe it was in the Tips & Tutorial section (surprise).  It dealt with the subject of working with P2 HD media, transcoding to SD and back again. I believe within MC software.  Short, to the point.  However, I can't seem to find it.  Can anyone steer me in the right direction?

Thanks in advance.

Bill

Was it one of these?:

Working with P2

Thanks BLKDOG.

Those are helpful.  We did find the original link to which I referred.  However, it's been jumping on and off the site all day.  Must have something to do with the server issues.

http://community.avid.com/blogs/training/archive/2008/a1/28/302579.aspx

One more question if you'll induldge me.  We shot some test footage on our HVX200 DVCPRO50 720p 24p (P2 card based) and would like to utilize it in an ONLINE SD edit.  We have been using a P2 workflow for about 8 months (all SD based footage) with few issues.  Being new to HD fun, however,  I'm sure we're missing something but we are finding that regardless of our transcode settings to SD (DV25, DV50, 1:1, etc.) the resolution of this footage is less than desirable when played back both in the timeline and client monitor.  In other words, it isn't of the same quality level had it been shot natively at 480i 24p.  I'm aware of the format issues involved in terms of aspect ratio, etc.  But I'm actually referring to the resolution quality of the footage (artifacting, graininess, etc.).  The footage looks fine when played back in its native HD format.  Our objective is to archive footage in HD for future use while posting and delivering in SD for the time being.

A "newbie to HD" question to be sure.  But I'd appreciate any advice.

Thanks folks!

Bill

Well Bill, I'm not an expert on HD by any means but, when you go from an HD source to an SD downconvert, you are really talking about a much lower quality picture to begin with.

If you compare the HD out of that camera to the SD image you transcode, I would expect it to look worse. The question would be, how much worse does it look compared to the same footage shot in SD to begin with.

Bill - I saw BLKDOGs' post and kinda disagree. :) We don't use P2 so on that front I can offer no help, but DVCPRO100 footage from an Pana. HDX-900 looks better downconverted to SD (via a Panasonic 1400 deck) than orginal SD footage shot on an SDX-900. I suspect something bad is happening in the software downconvert, HD downconverted to SD should still look great.

What do you disagree with Fazz? That's exactly what I said.

The comparison is not between HD and SD but Between Downconverted SD and Actual SD.

"I would expect it to look worse. The question would be, how much worse does it look compared to the same footage shot in SD to begin with".

All I'm saying is in our experience HD to SD looks better than native SD. We've done camera comparison tests and the results were stunning. Your use of "worse" is of course subjective, but it sounds like Bill is seeing more degragation than normal.

Exactly but I can't make that call from here.  That's why I was asking.

billhsp:

One more question if you'll induldge me.  We shot some test footage on our HVX200 DVCPRO50 720p 24p (P2 card based) and would like to utilize it in an ONLINE SD edit.  We have been using a P2 workflow for about 8 months (all SD based footage) with few issues.  Being new to HD fun, however,  I'm sure we're missing something but we are finding that regardless of our transcode settings to SD (DV25, DV50, 1:1, etc.) the resolution of this footage is less than desirable when played back both in the timeline and client monitor.  In other words, it isn't of the same quality level had it been shot natively at 480i 24p.  I'm aware of the format issues involved in terms of aspect ratio, etc.  But I'm actually referring to the resolution quality of the footage (artifacting, graininess, etc.).  The footage looks fine when played back in its native HD format.  Our objective is to archive footage in HD for future use while posting and delivering in SD for the time being.

I think that the problem lies in the fact that you're trying to transcode progressive video into interlaced.  This is something I don't believe that Avid is capable of doing at this time.  In my experience, in order to take P & I footage in and out of the other respective projects, I've had to export the media and then reimport into the target project.  Typically, if I need an SD copy of HD footage, I just take it off the downconverted video spiggot on the back of the deck.  Since you're working with P2, that's probably not an option.

Try exporting your HD P2 media from your HD Avid project as a QT Ref file.  Then take and import those QT ref files back into an SD interlaced project.  I've used a similar process to go from SD to 720P HD, and it works pretty slick (though time consuming).  The only wildcard I see to this is that your HD footage was shot in 24P.  I'm not 100% sure that the reimport will apply the necessary 3-2 conversion to make it 30 frame.  But, you won't know until you try. . .

Good Luck,

CR

Thanks to everyone for their input.  It's been very helpful.

We are making progress using a bit of all of your suggestions.  It's a bit of trial and error issue.  We are pretty confident though that AVID can indeed ingest 720p 24p (P2 based) media and transcode to 1:1 MXF SD (it appears a 1:1 transcode is necessary). We were able to perform a 16:9 reformat a few other tweaks and bingo.  Since we're not yet 100% confident in the workflow just yet -- we'll post a complete workflow if and when we're confident in its soundness.  But I must say -- doing direct comparisons quickly this afternoon between 480i 24p SD and transcoded 720p 24p HD to SD -- the transcoded footage was significantly superior in the native 30i project.

Thanks again folks -- and we'll keep you "posted".

Bill