Search found 11936 matches

by snibgo
2019-08-24T09:50:51-07:00
Forum: Users
Topic: reproducing Spherical Distortion Map
Replies: 9
Views: 269

Re: reproducing Spherical Distortion Map

IM v6 by default doesn't process alpha. IM v7 by default does process alpha, so we can use "-alpha off" when we really don't want alpha. "-fx" is evaluated at every pixel, so I replace that with "-evaluate Add %%[fx:...]" etc where the fx is evaluated only once per image. I use "-compose Distort -co...
by snibgo
2019-08-24T07:08:29-07:00
Forum: Users
Topic: reproducing Spherical Distortion Map
Replies: 9
Views: 269

Re: reproducing Spherical Distortion Map

Displacement maps need to be high-precision. A small error (eg quantization) such as one part in 500 in an ordinary image may be invisible, but the same error in a displacement map will be far more obvious in the displaced result. The zig-zags come from a low-precision displacement map. For images a...
by snibgo
2019-08-23T17:55:18-07:00
Forum: Developers
Topic: [Github] [Latest] Android Imagemagick 7
Replies: 5
Views: 127

Re: [Github] [Latest] Android Imagemagick 7

Great stuff, thanks.
by snibgo
2019-08-23T07:23:32-07:00
Forum: Users
Topic: Place 2 images side by side
Replies: 3
Views: 123

Re: Place 2 images side by side

This is an ImageMagick forum. I have shown you the ImageMagick command. If you also need help writing Windows scripts, I suggest you find a Windows script forum.
by snibgo
2019-08-22T13:45:47-07:00
Forum: Users
Topic: Place 2 images side by side
Replies: 3
Views: 123

Re: Place 2 images side by side

What version of IM? On what platform?

The IM command could be something like:

Code: Select all

magick in_before.jpg in_after.jpg +append out.jpg
You will need a shell script to loop through the files and manage the filenames.
by snibgo
2019-08-22T11:36:39-07:00
Forum: Developers
Topic: identify returns different results for HTTPS than for local source
Replies: 8
Views: 271

Re: identify returns different results for HTTPS than for local source

I suggest you post in the bugs forum https://www.imagemagick.org/discourse-server/viewforum.php?f=3 I would go with your first title, to report that bug. If you also wish to report that "dng:https://somewhere..." doesn't work, I suggest you report that as a separate bug. Each report can contain link...
by snibgo
2019-08-22T10:42:41-07:00
Forum: Developers
Topic: identify returns different results for HTTPS than for local source
Replies: 8
Views: 271

Re: identify returns different results for HTTPS than for local source

Does anyone think this warrants a bug report? Yes. I think putting the format within the URL eg "https://somewhere/jpg:myfile.jpg" is wrong, and I think IM should complain. I'm not surprised IM gets confused. But "http://somewhere/myfile.dng" should be read as a dng, not a simple tiff, and that see...
by snibgo
2019-08-22T09:00:36-07:00
Forum: Developers
Topic: identify returns different results for HTTPS than for local source
Replies: 8
Views: 271

Re: identify returns different results for HTTPS than for local source

With IM v6.9.9-50 and 7.0.7-28 I get the same result as you: if I wget the file and identify it locally, IM processes it correctly as a DNG, but when IM accesses over the net it processes it as a TIFF and reads a thumbnail from it. I don't know why IM gets that wrong. A developer would need to take ...
by snibgo
2019-08-21T10:57:06-07:00
Forum: Users
Topic: Resize images based on their orientation
Replies: 7
Views: 1271

Re: Resize images based on their orientation

What type of images are they? JPEG compression was designed for photos. We can give better advice if you supply a link to a sample input.
by snibgo
2019-08-21T06:55:25-07:00
Forum: Users
Topic: reproducing Spherical Distortion Map
Replies: 9
Views: 269

Re: reproducing Spherical Distortion Map

I'm a bit lost. Do you have an unanswered question? ...the run time of the sphere_lut generation is very high even in the 1500x1500 test case ... "-fx" is slow. I find it too slow to be useful for images that have more than, say, 64000 pixels. Generally there are faster alternatives: "-evaluate", "-...
by snibgo
2019-08-21T06:43:39-07:00
Forum: Digital Image Processing
Topic: Bicubic (Catrom) image downsampling without antialiasing?
Replies: 7
Views: 418

Re: Bicubic (Catrom) image downsampling without antialiasing?

I don't know Matlab, or what it does in what sequence. IM doesn't have a anti-alias operation. There is no mechanism to "anti-alias" an image. I don't know what such an operation might do. IM does have an "-antialias" setting that affects some operations. For example, when drawing a diagonal black l...
by snibgo
2019-08-21T05:48:53-07:00
Forum: Users
Topic: Resize images based on their orientation
Replies: 7
Views: 1271

Re: Resize images based on their orientation

You could add compression and quality like this:

Code: Select all

convert -quiet -units PixelsPerInch <input> -scale 50% -density 72 -resize 2048x2048 -compress JPEG -quality 50 <output>
I removed "-define jpeg:extent=2048kb" because it has no effect when writing TIFF files.
by snibgo
2019-08-21T05:44:41-07:00
Forum: Users
Topic: masking two BW-TIFs
Replies: 2
Views: 124

Re: masking two BW-TIFs

What version of IM, on what platform? I'll assume v7, on Windows.

Code: Select all

magick maske.png -negate hrot.png -compose Lighten -composite out.png
by snibgo
2019-08-21T05:16:08-07:00
Forum: Bugs
Topic: .png to .pdf conversion is failing with memory allocation error.
Replies: 3
Views: 186

Re: .png to .pdf conversion is failing with memory allocation error.

Your "-resize !" is not documented syntax. What do you want IM to do with it? For v7, I suggest you use "magick", not "convert" or "magick convert". Your input is large, 315 M pixels. For me, IM v7.0.7.-28 on a Windows 12 GB laptop, the command ... magick 001_25.png -density 200 x.pdf ... works fine...