VirtualDub's "Codec-friendly sizing" what is it for?

[synnchan]

What does that "Codec-friendly sizing" option do? Let's say I want to upscale my video to 8x, will changing it to "Multiples of 8" do anything?

[pandy]

Depend on codec - for some it can be 16 for some 8 for some 64 or more (depend on max block size).

[raffriff42]

No, it adjusts the output size you ask for to be divisible by 2, 4, 8 etc.

8x enlargement is always going to be mod 8, but the problem can arise if you enlarge by percent.

For example 640x480, enlarged 1.33 = 851.2x638.4. Without adjustment, that's 851x638. Odd sizes are usually not allowed except in RGB mode. Adjusted to mod-8, that's 848x632 (try it).

Note this can warp the aspect ratio a tiny bit.

[synnchan]

Oh... that's a shame then. I thought it had anything to do with compressing the files better.

I'm trying really hard to find a good compression method here. I work with pixel oriented game videos and capture them with a lossless codec (either camstudio or lagarith) at RGB, then upscale them to either 8x or 9x with point resize. But they add up and take a lot of space here in my HDD.

Do you guys have any compression tips for archiving purposes?