Search found 188 matches

by henrywho
2012-04-02T03:58:17-07:00
Forum: Users
Topic: How?: colorspace/gamma aware resize for Grayscale Images
Replies: 8
Views: 23573

How?: colorspace/gamma aware resize for Grayscale Images

I am playing with the large ring image http://www.imagemagick.org/Usage/resize/rings_lg_orig.png again.... this time with version 6.7.6-3-Q16-windows http://www.imagemagick.org/download/binaries/ImageMagick-6.7.6-3-Q16-windows.zip [1] convert.exe rings_lg_orig.png -distort resize 150x150! 01.png [2]...
by henrywho
2012-04-02T03:39:12-07:00
Forum: Users
Topic: Alternative to modulate command to increase Saturation
Replies: 40
Views: 55143

Re: Alternative to modulate command to increase Saturation

Yet another approach is to use -color-matrix under linear RGB, as described in http://www.graficaobscura.com/matrix/index.html For example, to increase the saturation by a factor of 1.1 without changing luminance (hopefully), I use the following matrix: -color-matrix " 1.07875 -0.07154 -0.00721 -0.0...
by henrywho
2011-09-11T23:09:13-07:00
Forum: Bugs
Topic: Bug when saving gray images as miff after "-colorspace sRGB"
Replies: 2
Views: 6390

Re: "-colorspace" + gray + miff = Error

This bug is still found in "ImageMagick-6.7.2-5-Q16-windows-static.exe"
by henrywho
2011-09-08T06:18:40-07:00
Forum: Bugs
Topic: Bug when saving gray images as miff after "-colorspace sRGB"
Replies: 2
Views: 6390

Bug when saving gray images as miff after "-colorspace sRGB"

Binary: http://www.imagemagick.org/download/binaries/ImageMagick-6.7.2-Q16-windows.zip (exe binaries dated 8 Sep 2011) Test image: http://www.imagemagick.org/Usage/resize/rings_lg_orig.png Good: convert rings_lg_orig.png -resize 150x150! 01.miff Good: convert rings_lg_orig.png -depth 16 -resize 150x...
by henrywho
2011-08-23T00:52:27-07:00
Forum: Bugs
Topic: -colorspace no longer working
Replies: 17
Views: 32878

Re: -colorspace no longer working

Thank you very much for maintaining such a great piece of software.
by henrywho
2011-08-18T03:12:31-07:00
Forum: Bugs
Topic: -colorspace no longer working
Replies: 17
Views: 32878

Re: -colorspace no longer working

Perhaps I did not made myself clear enough. I have put the test files in http://www.mediafire.com/?qa0xmdc79e0zubr
by henrywho
2011-08-17T23:51:10-07:00
Forum: Bugs
Topic: -colorspace no longer working
Replies: 17
Views: 32878

Re: -colorspace no longer working

I do expect the intermediate MIFF to stay as 16bit linear (I thought it always does).

What amazed me is that there is no error for 24bit color images (producing the final PNG in non-linear sRGB values). Yet 24bit gray images have the final PNG produced in linear RGB values (in 8bit depth).
by henrywho
2011-08-17T22:02:38-07:00
Forum: Bugs
Topic: -colorspace no longer working
Replies: 17
Views: 32878

Re: -colorspace no longer working

There still seems to be some problem with gray images (no matter stored in a 8bit gray or 24bit color manner) in version 6.7.1 (Q16). Take the famous 1000x1000 Ring1.gif as example: convert.exe Rings1.gif -depth 16 -colorspace sRGB -distort resize 100x -colorspace RGB -depth 8 rings1_small_direct.pn...