I was searching around for some information on 16:9 DVD's and ran across the Afterdawn Divx5 Encoding Guide. I think there are some errors though in the information and method provided.
A small thing, but according to the guide the resolution must be a multiple of 16. From the Divx.com site the resolution can be "any integer with a multiple of 4"
The real problem I see with the method recommended is the filter order. The guide recommends resizing first and cropping later. Obviously, if you follow this filter order you can no longer crop out the vertical black areas along the sides of the frames. This would make cropping pretty pointless. You crop to remove the black bars which if left in kill the quality of your encode. Actually, its the point where the black bar meets the frame. There is an abrupt edge there between the static black line and the dynamic film area of the frame which eats up your bits. Yet, the Guide seems to believe this method is preferable to prevent distortion. This is silly though. You horizontally crop the video maybe 10-16 pixels max and then resize to the original aspect ratio of the frame. Stretching a 704x405 image to to the correct 16:9 720x405 resolution is negligible. That's a whole whopping 2 percent distortion! It would take quite an acute eye (impossibly so) to detect that. Plus you have correctly cropped out your black bars to allow for efficient bit allocation. Your encodes will look much better as your bits will go to data in the frame rather than being wasted defining edge between your film and the black bars.
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