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TheManuel
31st October 2006, 03:29
I am capturing from my Hi8 camcorder at 720x480 for DVD as my final format with a Philips 7134 based capture card. If I capture at 720, 704 or 640 as horizontal resolution, I never get black borders. In fact, all images look pretty much identical.
If this is the case, does that mean I don't have to crop anything to get the correct aspect ratio in the final DVD format?

Thanks.

Awatef
31st October 2006, 13:12
Yes, you don't have to crop.
Just capture in 720x480 and throw it to your MPEG-2 encoder. By default, it will assign a 4:3 flag to it and make it look in the right aspect during playback.
PS: if you shot your movies in 16:9, you have to change the flag to 16:9 of course.

TheManuel
31st October 2006, 14:38
Thanks Awatef.

I always shoot in 16:9 (gambling that in the future this will be the standarad aspect ratio for display devices) and take care that the encoder and my authoring programs know the footage is 16:9.
What I was worried about is the fact that some cards have different active capture windows than others with the result that the captured footage has the aspect ratio slighly off.

Now, one more:
Why does my captured footage at 640, 704 and 720 all look the same way? Is there a disadvangate to capturing at 640 to save on disk space (no big deal, I have enough but I'm curious?

Thanks.

Awatef
31st October 2006, 20:44
There is a disadvantage in that your MPEG-2 encoder will have to resize to 720.
You don't have to worry about the aspect ratio. You should enable 16:9 output in your camcorder to avoid black bars during the capture, and then specify 16:9 in the DVD encoder.

Why your capture always look the same? May be you have your player set to a fixed aspect ratio?

TheManuel
1st November 2006, 02:12
There is a disadvantage in that your MPEG-2 encoder will have to resize to 720.
You don't have to worry about the aspect ratio. You should enable 16:9 output in your camcorder to avoid black bars during the capture, and then specify 16:9 in the DVD encoder.
I figured as much but wanted to be sure. Thankfully, my camcorder supports 16:9 (both real and letterbox).

Why your capture always look the same? May be you have your player set to a fixed aspect ratio?
I was referring to the fact that they both look the same in the computer using VirtualDub, i.e. no black borders and seemingly equal quality except, of course that the 720 looks wider because it has more pixels....
...because of the increased resolution... doh! Never mind, I just answered my own question.

Thanks for all your help.