Comments by KateToo (Top 5 by date)

Still not following you. I can access the pixels directly, yes - but how do I map from one size to another?
Are there re-sampling functions I'm missing?
All I'm aware are of the StretchBlt and Graphics.DrawImage. Generally StretchBlt works great except for this occasional mirrored image.

I do check the DEST and SOURCE and do not resample if the same.

Can you point me to what functions you mean for the pixel-wise resampling operations?

I'll take a look at artuxsoft, thanks.

I do check the sizes and if they are the same use BitBlt.
What would you suggest for the resampling? Isn't that basically what I'm using StretchBlt for? My work around is actually to use Graphics.DrawImage so I dont need StretchBlt ... but this is too slow.

Please let me know if there is some other way to do the resample that is quick that I'm missing.
Thanks!

I had read that, yes, but it is not the cause.
Those values are never negative, and the exact same values for those, from one image to the next, can result in one of the images having been flipped.