mattia on wrote... | Hello, | | I have an 8 bit grey scale tiff image; size 1500x4600, 6MB | | I am trying to do the following to operate a convolution : | | *convert b1.tif -convolve "0,1,0,1,1,1,0,1,0" out1.tif | | *Where b1.tif is the original image... | | But, out1.tif looks completely unchanged as if no operation happened... | | The shell looks like this when I run the command: | | [EMAIL PROTECTED]:~/Desktop/data/prove$ convert b1.tif -bias 0 -convolve | "0,1,0,1,1,1,0,1,0" out1.tif | convert: b1.tif: unknown field with tag 42112 (0xa480) encountered. | `TIFFReadDirectory'. | [EMAIL PROTECTED]:~/Desktop/data/prove$ * | | The warning I guess can be ignored as the same kind of thing happens if I | invoke the command on a PGM image (but with no Tiff realated warnings) | | Final note: the original image is 6MB, the output one is 12MB | | I am confused, please help!! | What is happening? How can I get my convolution to run flawless?? | | Regards |
I tried this with the built in image rose: and the resulting image was a little fuzzier. convert rose: -convolve "0,1,0,1,1,1,0,1,0" rose.png In summery, it works for me! Note the fuzzyness is very very slight, so unless you 'flicker compare' the two images without resize, or scale enlarged, you may not see any result. Also not the results is divided by 5 to ensure the image is not 5 times brighter than it should be. If accuracy is important, I would use at least a IM Q16 version, (not Q8) or you will get quantium effects. You could also use a HDRI version of IM to use floating point real numbers in the internal storage. However these only specify internal 'accuracy' of the image, when you plan to do multiple operations with the same image within the same IM command (or API invocation) and thus requiring more memory usage. Such accuracy however will still be lost when the image is saved to a less accurate image file format. See IM Examples, Basics, Quality and Depth http://imagemagick.org/Usage/basics/#depth Also try some other operator (like -negate) on your TIFF, image an make sure Im is reading and processing the image correctly. Anthony Thyssen ( System Programmer ) <[EMAIL PROTECTED]> ----------------------------------------------------------------------------- If Dijkstra had given the five philosophers a chinese meal, he could've avoided his silly problem altogether by giving them chopsticks!! -- Paraphrase of the Logic of Chengzeng Sun ----------------------------------------------------------------------------- Anthony's Home is his Castle http://www.cit.gu.edu.au/~anthony/ _______________________________________________ Magick-users mailing list [email protected] http://studio.imagemagick.org/mailman/listinfo/magick-users
