Search found 8884 matches

by anthony
2018-02-07T17:52:33-07:00
Forum: Developers
Topic: Crop to an aspect ratio with "-crop 3:2"
Replies: 9
Views: 729

Re: Crop to an aspect ratio with "-crop 3:2"

Whether to actually switch from 3:2 to 2:3 depending on image orientation may need to a option for users that do NOT want to do it (EG; they are fitting photos into a thumbnail array). I do think this will need to be a separate option, as there is currently no way to determine if a ':' was used in a...
by anthony
2018-02-07T17:08:52-07:00
Forum: Developers
Topic: Crop to an aspect ratio with "-crop 3:2"
Replies: 9
Views: 729

Re: Crop to an aspect ratio with "-crop 3:2"

This is a viewport crop, which is similar to the calculated 'Centered Square Crop' http://www.imagemagick.org/Usage/distorts/#centered_square of course with IMv7 you can do this using -extent instead ;-) It is also related to a rotate-and-resize-crop method http://www.imagemagick.org/Usage/distorts/...
by anthony
2018-01-21T20:14:21-07:00
Forum: Users
Topic: How do I Apply Multiple Screen and Multiply to one image?
Replies: 4
Views: 370

Re: How do I Apply Multiple Screen and Multiply to one image?

If you are composing multiple images together with the same compose method then you can also use the laying operators to do this... http://www.imagemagick.org/Usage/layers/#compose The only tricky part about this is that the first image (the background color) needs to be selected to be white, black,...
by anthony
2018-01-18T18:36:19-07:00
Forum: Users
Topic: looking for docs for PRINT command
Replies: 12
Views: 1537

Re: looking for docs for PRINT command

Also see Identify Output Alternatives...
http://www.imagemagick.org/Usage/basics/#identify_alt
The main difference between "-identify" and "-print", is that first will be run once for every image in memory, while the later will only run once.
by anthony
2018-01-18T18:17:14-07:00
Forum: Users
Topic: How to colorize an image?
Replies: 13
Views: 1353

Re: How to colorize an image?

For additional information on specifying colors...
http://www.imagemagick.org/Usage/color_basics/#colors

And for the myriad methods and techniques available in re-coloring images...
http://www.imagemagick.org/Usage/color_mods/

For tinting...
http://www.imagemagick.org/Usage/color_mods/#tinting
by anthony
2018-01-18T17:54:04-07:00
Forum: Users
Topic: Crop sprites for minimal spritesheet size
Replies: 19
Views: 1745

Re: Crop sprites for minimal spritesheet size

I do not know if this will be useful to this discussion, as I can't find any link to a set of example images to try it on. Have you looked at... -layers trim-bounds This takes images with virtual offsets, and ignores the existing 'canvas' size. It then sets all the images so they have the same sized...
by anthony
2017-12-07T17:58:00-07:00
Forum: Users
Topic: why is median of a sequence of images slower than mean
Replies: 13
Views: 1585

Re: why is median of a sequence of images slower than mean

I have updated IM Examples, adding a actual example for median
Its not a great example, but it does the job.
http://www.imagemagick.org/Usage/layers ... seq_median
by anthony
2017-12-07T16:23:57-07:00
Forum: Users
Topic: why is median of a sequence of images slower than mean
Replies: 13
Views: 1585

Re: why is median of a sequence of images slower than mean

The command line discards the source images, basically as it only has a single image list, so results of a image process replaces the source image list. However the imagemagick library does not have that restriction. The results are returned as a completely separate image list, preserving the source...
by anthony
2017-11-30T16:35:25-07:00
Forum: Users
Topic: why is median of a sequence of images slower than mean
Replies: 13
Views: 1585

Re: median of a sequence of images operating pixel-by-pixel

It probably should be using -intensity.

also rather than necro-posting you should have started a new post.
I am splitting the post into a separate topic.
by anthony
2017-11-23T16:34:06-07:00
Forum: MagickWand for PHP
Topic: Transparent colour goes black when png/gif resized and conve
Replies: 11
Views: 31562

Re: Transparent colour goes black when png/gif resized and conve

Better still look at which has a number of different examples of the problem and how to fix it/ IM Usage Examples, Removing Transparency from Images http://www.imagemagick.org/Usage/masking/#remove The section of example immediately above that introduces the -alpha image processing operators. Also t...
by anthony
2017-11-19T18:15:46-07:00
Forum: Users
Topic: Compare -FUZZ <- how it is calculated
Replies: 20
Views: 2559

Re: Compare -FUZZ <- how it is calculated

Hmmm one side effect of -metric PAE. if you compare any image to another that is the same size but all black PAE will get you the largest color value in the image. On the other hand MAE will get you the average of all the color values in the image. Note this is over ALL color channels. A -metric FUZ...
by anthony
2017-11-19T18:05:37-07:00
Forum: Users
Topic: Compare -FUZZ <- how it is calculated
Replies: 20
Views: 2559

Re: Compare -FUZZ <- how it is calculated

If I use an extrememly high fuzz factor of 82% (larger that the .81 value we had before), then black and cyan SHOULD be the same! [b]compare xc:black xc:cyan -metric AE -fuzz 82% null:[/b] 1 As you can see I have the WRONG result! Something is not correct, and I will be report this though it may be...
by anthony
2017-11-16T17:52:16-07:00
Forum: Users
Topic: Compare -FUZZ <- how it is calculated
Replies: 20
Views: 2559

Re: Compare -FUZZ <- how it is calculated

The -metric AE is completely different to PAE. AE only returns a boolean (error or not-error) result, returning total count of the number of different pixels. So normally is ANY pixel is different it is different! [b]compare xc:black xc:cyan -metric AE null:[/b] 1 However AE is one of the few metric...
by anthony
2017-11-13T21:38:34-07:00
Forum: Users
Topic: Compare -FUZZ <- how it is calculated
Replies: 20
Views: 2559

Re: Compare -FUZZ <- how it is calculated

Internally IM uses its compile time quaility setting. 8 bit images are stored at that quality and then saves at the current image 'depth' whcih is usualy the image input depth. Also HDRI versions of IM store values a floating poitn numbers in memory but use Q16 as a base for those numbers. EG typica...