TIFF and LibTiff Mail List Archive


2000.10.14 22:15 "tif_getimage.c and YCbCr", by Frank Warmerdam
2000.10.14 23:31 "Re: tif_getimage.c and YCbCr", by Tom Lane
2000.10.16 09:17 "Re: tif_getimage.c and YCbCr", by Rick LaMont

2000.10.14 22:15 "tif_getimage.c and YCbCr", by Frank Warmerdam


There seem to be some serious bugs in the YCbCr support in tif_getimage.c (the ReadRGBAImage code) for odd sized images. For instance it doesn't work properly for 4,4 sampled code unless the image width and height is a multiple of four (and strip or tiles sizes are also a multiple of four).

Before I spend alot of time trying to fix this I would ask:

The bugs can be reproduced by converting an odd sized image to YCbCr form with "rgb2ycbcr -h 4 -v 4 -c none", and then trying to convert back to RGBA with tiff2rgba.

Best regards,

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