TAD
To make the picture look the same when converting a LOW-RES image to
HI-RES, you need to enlarge only the WIDTH (specifically LOW-RES/INTERLACE
to HI-RES/INTERLACE).
But, you may not have enough RAM for the 24 bit data after the enlargement.
That image would require 640 X 400 X 30 / 8 BYTES of contiguous fast ram.
pk