Convert from HD to DV at DVinfo.net

Dean Pavlov · November 24th, 2004, 01:00 AM

This is a newbie question but is driving me nuts. I have the HDV footage in my computer, but when I try to convert it to DV it looks horrible with these horizontal lines all over the place. I figured I need to deinterlace footage. I did so, but it is still there.

I am assuming this has something to do with the fact that I'm converting to 720X480 square pixels in virtualdub. How do I do this properly?

Rob Lohman · November 24th, 2004, 07:12 AM

The big question is what program are you using? The program
needs to downsample the higher resolution to the more normal
resolution. The quality of the end result depends on the algorithm
being used and the quality with which it was implemented. In
most programs you can choose which algorithm it should use for
such downsampling.

Dennis Adams · November 24th, 2004, 07:33 AM

The software that does the scaling will need to separate the fields before scaling. It sounds like your software is scaling the whole interlaced frame, which will produce the moire patterns you are seeing.

///d@
Sony Media Software

David Kennett · November 24th, 2004, 09:00 AM

I get excellent results using TMPGEnc MPEG encoder. It's inexpensive, and arguably does the best job of ANY encoder, regardless of price. It has the added benefit of allowing you to "map" the 1280x720 onto the 720x480. This way, you can crop, letterbox, stretch, or do something in between.

Just noticed you said DV. If your ultimate purpose is to make DVD, this method works fine though.

Dean Pavlov · November 24th, 2004, 11:33 AM

I resize deinterlaced and then reinterlace. There are still moire patterns. I have done a TMPGEnc resize too and this looks _considerably_ better, but still not 100% moire pattern free when reinterlaced.

Graham Hickling · November 24th, 2004, 12:30 PM

Two thoughts - dunno if either is relevant but just my $0.02

1) Are you aware that DV footage does NOT use square pixels?

2) Have you tried reversing field order (either when you deinterlace, or when you reinterlace)?

Dean Pavlov · November 24th, 2004, 12:34 PM

<<<-- Originally posted by Graham Hickling : Two thoughts - dunno if either is relevant but just my $0.02

1) Are you aware that DV footage does NOT use square pixels?

2) Have you tried reversing field order (either when you deinterlace, or when you reinterlace)? -->>>

1) Yes, I know, and I figure that's why using virtualdub just won't work out, however even when properly resized it does not look quite as good as should

2) Obviously, I should have checked that. I'll do it again and see if that helps.

Heath McKnight · November 25th, 2004, 09:59 AM

On the HD10, you can up or down convert footage to 1080i or all the way down to 480i. You just set it through the camera and hook it up to another deck.

heath

November 24th, 2004, 01:00 AM	#1
Dean Pavlov New Boot Join Date: Nov 2004 Location: Canada Posts: 6	Convert from HD to DV This is a newbie question but is driving me nuts. I have the HDV footage in my computer, but when I try to convert it to DV it looks horrible with these horizontal lines all over the place. I figured I need to deinterlace footage. I did so, but it is still there. I am assuming this has something to do with the fact that I'm converting to 720X480 square pixels in virtualdub. How do I do this properly?

November 24th, 2004, 07:12 AM	#2
Rob Lohman RED Code Chef Join Date: Oct 2001 Location: Holland Posts: 12,514	The big question is what program are you using? The program needs to downsample the higher resolution to the more normal resolution. The quality of the end result depends on the algorithm being used and the quality with which it was implemented. In most programs you can choose which algorithm it should use for such downsampling. __________________ Rob Lohman, visuar@iname.com DV Info Wrangler & RED Code Chef Join the DV Challenge \| Lady X Search DVinfo.net for quick answers \| Buy from the best: DVinfo.net sponsors

November 24th, 2004, 09:00 AM	#4
David Kennett Major Player Join Date: Jul 2003 Location: North Ridgeville, Ohio Posts: 407	I get excellent results using TMPGEnc MPEG encoder. It's inexpensive, and arguably does the best job of ANY encoder, regardless of price. It has the added benefit of allowing you to "map" the 1280x720 onto the 720x480. This way, you can crop, letterbox, stretch, or do something in between. Just noticed you said DV. If your ultimate purpose is to make DVD, this method works fine though. __________________ Dave

November 25th, 2004, 09:59 AM	#8
Heath McKnight MPS Digital Studios Join Date: Apr 2003 Location: Palm Beach County, Florida Posts: 8,531	On the HD10, you can up or down convert footage to 1080i or all the way down to 480i. You just set it through the camera and hook it up to another deck. heath __________________ My Final Cut Pro X blog

November 24th, 2004, 07:33 AM	#3
Dennis Adams Regular Crew Join Date: May 2003 Location: Madison, WI Posts: 123	The software that does the scaling will need to separate the fields before scaling. It sounds like your software is scaling the whole interlaced frame, which will produce the moire patterns you are seeing. ///d@ Sony Media Software

November 24th, 2004, 11:33 AM	#5
Dean Pavlov New Boot Join Date: Nov 2004 Location: Canada Posts: 6	I resize deinterlaced and then reinterlace. There are still moire patterns. I have done a TMPGEnc resize too and this looks _considerably_ better, but still not 100% moire pattern free when reinterlaced.

November 24th, 2004, 12:30 PM	#6
Graham Hickling Trustee Join Date: May 2004 Location: Knoxville, Tennessee Posts: 1,669	Two thoughts - dunno if either is relevant but just my $0.02 1) Are you aware that DV footage does NOT use square pixels? 2) Have you tried reversing field order (either when you deinterlace, or when you reinterlace)?

November 24th, 2004, 12:34 PM	#7
Dean Pavlov New Boot Join Date: Nov 2004 Location: Canada Posts: 6	<<<-- Originally posted by Graham Hickling : Two thoughts - dunno if either is relevant but just my $0.02 1) Are you aware that DV footage does NOT use square pixels? 2) Have you tried reversing field order (either when you deinterlace, or when you reinterlace)? -->>> 1) Yes, I know, and I figure that's why using virtualdub just won't work out, however even when properly resized it does not look quite as good as should 2) Obviously, I should have checked that. I'll do it again and see if that helps.