Exported DVC Pro HD file with incorrect aspect ratio when transcoded for HD DVD

[David Roth weiss]

I don’t know why you’re having the problem, but I would hazard a guess that you could fix it in the geometry window by simply checking custom, and entering 1920×1080.

David Roth Weiss
Director/Editor/Colorist
David Weiss Productions, Inc.
Los Angeles

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[Adam White]

Hi David, thanks for your response.

The dimensions (encoded pixels) section of the geometry tab is grayed out and locked to “Automatic” and cannot be altered, which is another oddity! If I change the output image inset (padding) to “16:9 1.78:1” then the resulting video has the correct ratio, but is pillar-boxed on either side of the image.

[Rafael Amador]

And what are you doing exporting something for the web in HD (DVCProHD) pixels?
Everything for the web MUST be Square pixels.

ADAM, to make any 16×9 clip for the web, you must make sure that the sides (high/wide) keeps always this 16 to 9 proportion. So you can only use values like:
– 160 x 90
– 240 x 135
– 320 x 180
– 480 x 270..etc
If you export with QT, you will always get Square Pixels (as you need).
But if you use Compressor, be careful and check “Square pixels”.
If you just let “Pixels: Default for size” you can get some funny distortion on play.
Cheers,
rafael

http://www.nagavideo.com

[Adam White]

Hi Rafael. Thanks for your input.

This compression is not for a clip to go online. I’m compressing a H.264 file for HD DVD. I can’t seem to adjust any of the Dimensions settings in the Geometry tab because they are all locked, so I can’t change the aspect ratio to “Square pixels”.

[Rafael Amador]

Hi Adam,
Right. That’s correct. You have the “Pixels options” grayed, because for HD-DVD and Bluray, can not be options: They can only be Squared pixels.
Can you open the DVCProHD clip in QT Player and tell us what exactly says the Info Window?
And one question:
When you have imported your DVCProHD clip to Compressor, in “Video Format” have you properly identified the clip as 1440×1080?
rafael

http://www.nagavideo.com

[Adam White]

The info from QuickTime Player;
Format: DVCProHD1080i60, 1280 x 1080 (1888 x 1062), Millions.
FPS: 29.97
Data Size: 64.39GB
Data Rate: 116.64mbit/s

When importing the clip into Compressor, Video info appears as;
Econded Bounds: 1280×1080
Display bounds: 1920×1080
Pixel Aspect Ratio: DVCProHD 1080i (16:9)
Frame rate: 29.97

I have just done some tests converting the file for an NTSC SD DVD (my client needs standard definition copies too) and it works fine – the aspect ratio is correct. So it must be an H.264 setting that I haven’t got right. Any thoughts?

[Rafael Amador]

Adam,
What I want to know is the Info of the H264 that you get on exporting from Compressor.
Open the file in QT, and “Comm-I”.
Some where the Pixels aspect have been misinterpreted, and I think that when importing the DVCProHD file to Compressor.
Did you used a Compressor Preset?
rafael

http://www.nagavideo.com

[Adam White]

Hi Rafael, sorry I misunderstood your question.

The info from a test H.264 clip that I compressed is as follows;
Format: H.264, 1920 x 1080, Millions
FPS: 29.97

Yes, I used a preset from Compressor – namely HD DVD: H.264 90 Minutes. Then I just adjusted the bitrate accordingly to suit my requirements and set Video Format from ‘Automatic’ to ‘1920 x 1080’. I tried adjusting some of the geometry settings after I got exports with the wrong ratio, but none of these changes worked.

I’m sure I must be making a basic error somewhere along the way, maybe you can help?

Adam

[Rafael Amador]

Hi Adam,
Thinking and thinking, but no idea.
Size and Pixels aspects shouldn’t be an issue:
Try letting “Video Format: Automatic”.
What I would do is to avoid the HD-DVD Preset, and try to do a H264 with these specs.
I’m lost,
rafael

http://www.nagavideo.com

[Michael Gissing]

“When importing the clip into Compressor, Video info appears as;
Econded Bounds: 1280×1080
Display bounds: 1920×1080
Pixel Aspect Ratio: DVCProHD 1080i (16:9)
Frame rate: 29.97 ”

Strange numbers. Anamorphic 16:9 is 1440 x 1080. True 16:9 is 1920 x 1080 but 1280 x 1080 is weird.