Twice bigger row_sizeY - Logo filter

I am trying to write very, very simple Logo filter for Avisynth 2,5 to avoid converting to RGB and back. I have prepared some "skeleton" for this, but I must pass twice bigger values in X - I have found that "const int row_sizeY = dst->GetRowSize(PLANAR_Y);" return twice bigger values - thats for example 1440 for video 720x576. Why? Would anybody help me? Thanks Walda

Your video is most likely YUY2. Use vi.IsYUY2() to find out.

Thanks for Your answer, You're right, it's YUY2 and I should test it before posting ( You write about that on Your pages). But I am confused - its video captured by Digital8 camcorder - DV format is 4:2:0, so it is 12 bits? Yes, there are YUY2 16 bit with only "duplicated" second line of chroma, but the number of Y samples might be the same? On the other hand the "sceleton" for the filter is working except what i have written above. But just now I have no idea how to treat and compare normal bmp with double x-sized video ? Walda

It all depends on what your DV-codec wants to return, so I guess it only wants to return YUY2 data. Exchanging it for another might solve the problem - but maybe they behave the same.