Resize, Cropping Ratios. Math

[thomaslurv]

Hi, I've nearly done with all the queries.

I started out last week, encoding my first DVD with Flask. Now I'm using DVD2AVI, AVIsynth, Graphedit and Nandub.

The only problem I'm seeing now with resulting 512x384 DivX movies is some unsightly edges, so I need to crop the image.

When entering the cropping setting in AVIsynth are there any rules I should adhere to? I realise I should crop before I resize but can I crop any side by any value or must I stick with multiples of 16?

many thanks

thomas

[UncasMS]

the easiest way to generate avs files is using gordiaknot or dvx.

gordianknot and in particluar dvx will provide you with a very sophisticated gui to set bitrate, crop, use de-interlacing filters or smooth your video.

they will then create an avs file and load this avs into virtualdub for the final transcoding process.

dvx accepts all the latest codecs like xvid, divx 5.02 - 5.05 though gk version 0.28 might be a good choice as well.

you shouldnt go all the hard way - use those tools instead.

click the pics in my signature for more.

[thomaslurv]

Thanks, I've tried GK but didn't really like it.

I actually prefer writing the scripts myself. What I'm doing now is using the crop in DVD2AVI and then writing down the values to put in my script.

thomas

[Enchanter]

Re: Resize, Cropping Ratios. Math

Originally posted by thomaslurv
When entering the cropping setting in AVIsynth are there any rules I should adhere to?

Let's suppose you have a video with an original resolution of 720x480. Using the cropping utility found in either GK or Virtualdub itself, you have determined that you need to crop 12 points on the left-side, 12 on the right-side, 68 on the top side and 60 on the bottom side, resulting in a resolution of 696x352. Translated into the Avisynth command, you would input the following:

Crop(12,68,696,352) # Rule: Crop(left-crop,top-crop,resultant horizontal size, resulting vertical size)

Originally posted by thomaslurv
I realise I should crop before I resize but can I crop any side by any value or must I stick with multiples of 16?

Preferably.