TIFF and LibTiff Mail List Archive


1999.04.30 05:57 "YCbCr reader help", by Mike Schienle
1999.04.30 16:21 "Re: YCbCr reader help", by Tom Lane
1999.04.30 16:36 "Re: YCbCr reader help", by Mike Schienle

1999.04.30 16:36 "Re: YCbCr reader help", by Mike Schienle

Subsampling = 2, 2

I've set up a 1280x1000 array for each Y, Cb and Cr section. I expect to see the Y array filled, and 1/4 of the Cb and Cr arrays filled, which will then be enlarged to the size of the Y array.

I'm getting a little closer to the solution on this. At least I can make out the imagery, but it's obviously not correct. I'm trying to figure out if the data is 16 bit and I need to shift off 4 bits to Cr and 4 to Cb, or if it's all 8 bit and I need to split every other byte, or if it's something else completely.

That's correct for subsampling 2,2... but you do realize that *you* have to enlarge the Cb and Cr data, right?

Yup. Thanks for confirming. Is there a preferred means of enlarging them (nearest neighbor, bilinear, cubic, other)? I have no problem using any of the first three, but I'm in uncharted territory on this project.

libtiff doesn't do that for you.

Btw, where is libtiff these days? It's not at SGI's site.

Mike Schienle                                 Interactive Visuals, Inc.                  Remote Sensing and Image Processing         Analysis and Application Development