Newbie: MeGui, anamorphic encodes and aspect ratios? Confusion on forums

[aguy]

Hi,

Sorry about this question but there seems to be alot of confusion on the forums about aspect ratios.

I want to encode my DVD's for media server and HTPC use with x264 and MeGui.

My plan for anamorphic encodes is as follows. I wish to ask if people can see a major problem with this scheme. BTW I am in Australia so all sources are PAL DVD's (720 x 576). Example is for a 2.35:1 widesreen encoded DVD eg Star Wars Attack of the Clones.

1. Create D2V within MeGui
2. Use avisynth script generator in MeGUI:
- set input DAR to 16:9 (16:9 enhanced DVD)
- crop output to remove black mattes
- for above example crop to 0 left 72 top 72 bottom 0 right
- leaves output resolution of 720 x 432
3. In config section alter Sample Aspect Ratio to 47/20 (for 2.35:1)
- I believe actually refers to target DAR (not SAR) and MeGui calcultes necessary SAR.

How does this sound? I have found everything on the forums very confusing surrounding this issue.

Thanks, and sorry if this is going over old ground.

[nurbs]

There is a box in the avisynth script generator that sets anamorphic encoding. If you check that box you don't have to enter SAR, it will automatically be set when you open the avs for encoding. That should saves you one step, if you have a current built of MeGUI.

[berrinam]

Even better:
Create D2V with MeGUI, ticking 'load sources when finished'. This means it opens automatically in MeGUI and selects the correct input DAR (assuming the DVD says it correctly, which they always do ;))
Press Auto in cropping.
Press the button nurbs spoke about: 'Maintain Resolution and set AR in encoder' or something like that.
Save your AVS and queue your job. The AR will have been set for you
You are right in believing that it is actually the target DAR in the codec config windows. The labels are just wrong.

[aguy]

Thanks for these answers.

I used those suggestions and they worked well. Sounds like I was just doing those things manually. At least I had already figured out those steps myself.

Another question about cropping. Why does the autocrop often take off 2 pixels on the right and sometimes bottom. Won't this make the res non mod16 without resizing (something I don't want to do because I want to retain the original anamorphic resolution).

Thanks

[nurbs]

autocrop doesn't take mod16 into account since most people resize after cropping and those who don't often have to crop into the picture or leave some of the black borders to get the resolution their codec requires. It just cuts away everything that is totally black.
I noticed that sometimes it cuts 2 from the right although it is actually part of the picture and not just black. Also it won't cut lines that are half black and half picture.
If you don't want to cut into the picture and still do an anamorphic encode you can still do that. If you click the "suggest resolution" box, or whatever it says right next to the resize boxes, while 'Maintain Resolution and set AR in encoder' is checked it will resize to a proper resolution for an anamorphic encode. (like 720*xxx)