Legacy ImageMagick Discussions Archive

What I'm really wondering from this experiment is whether exploiting '-distort SRT 0' and 'colorspace' operators adds anything useful over other methods for removing halftone patterns like FFT spectrum notching. colorspace is probably useful to think about because it affects most methods, probably ...

Thanks to all. The form: compare -identify -metric MAE out_1.png out_2.png null: 1> identify.txt 2> metric.txt works perfectly. I didn't need the identify information file anyway, so I can just ignore that file. If you don't need it you could replace identify.txt with nul, or leave -identify out of...

snibgo wrote: As GreenKoopa has implied but not explicitly stated

As always, snibgo is much more articulate. Still, that anything coherent comes out of a turtle is remarkable.

snibgo wrote: the compare metric data goes to stderr, not stdout

This design choice is both genius and confusing.

I was going to create this example, but after some thought it doesn't seem too useful. First, the OP sets gravity, which -distort doesn't use. Your square example assumes a gravity of center. Second, the solution is less well defined when not a square. If the input image is 90x100 and 4:3 is request...

I would like to save a crop geometry for a future crop. This is the only solution I can think of. Any others? Page offsets may alternatively be positive. : Save an image with an area of interest specified. convert wizard: -repage 70x70-200-104 a.png : Verify that the page information has been saved....

I've been reluctant to try out anything labeled alpha, and I've been unable to find a HDRI build of 6.8.X for Windows. I'm happy to hear that 7 works well! I really should install and learn cygwin, then try building IM myself. Time is against us all. I don't immediately have any ideas for improvemen...

It is a problem with your quotes around the -draw arguments. Are you on Windows? Try swapping your use of single and double quotes.

Welcome. magick, does that mean you are using the version 7 alpha? Platform? I have been reading your posts but I honestly have nothing useful to add about filters. I do know a reasonable amount about colorspaces though.

Welcome. A good place to begin reading about compare: http://www.imagemagick.org/script/compare.php http://www.imagemagick.org/Usage/compare/ The first two images are input, the two to compare. The third image is output, a difference of the two inputs. When this output image is not wanted, null: may...

Does changing the -virtual-pixel affect the extra column you are getting? Unfortunately not. I am cropping an arbitrary (often interior) area of an image while down-sampling. To achieve accurate viewport offsets while using distort:scale, they must be moved into the -distort SRT arguments. The offs...

A FYI more than a question. I was having difficultly making my images line up after a -distort resize and crop. Sometimes they would, but other times it would be off by a little or an entire pixel. It turns out that the distort:viewport setting rounds all four values to integers. Then this is multip...

I was testing for an approximate parameter conversion, not the method, and this thread died for two weeks so I didn't keep my results. The graph of the GIMP unsharp was not smooth. Being 8-bit didn't help, but it seemed worse than that. Large values for amount in GIMP yielded poor results.

I did some testing for GIMP Radius = 0.5 - 6 and Amount = 1 - 6. I have determined that GIMP Amount is exactly the same parameter as IM Gain. IM Sigma is GIMP Radius plus not quite one, and IM radius is twice that. I find it strange that GIMP calls a parameter radius when pixels 2*(radius+1) distan...

jpeg compression splits an image into blocks of 8x8 pixels (a simplification which ignores chroma downsampling). The "best way to add a date stamp while minimizing loss of image quality" is to only recompress the blocks which were modified. ImageMagick, like most every image editor, lacks ...

Appears fixed in the new 6.8.6-7 release. Thank you.