Odd "+noise" "-modulate" and "-blur" result
Posted: 2017-01-11T13:08:03-07:00
ImageMagick 7.0.4-3 on Windows 10 64: I'm working a command that uses "+noise", "-modulate", and "-blur". I ran into a combination that creates an odd result, and I narrowed it down to a very short command to test the issue...
The output of that command is covered with small black squares...
If I omit "-alpha set", the output image is all black.
If I use "+noise" with any types other than "poisson", the issue doesn't occur.
If I omit either the "-modulate" or "-blur", the black squares won't be there. If I switch their order by putting the "-blur" before the "-modulate", the squares don't appear. It doesn't seem to matter what modulate settings I use. The squares do appear with blur settings other than "0x1", including "0x0", but will be different sizes of small black squares depending.
I can easily avoid using this construct for my purposes, but if someone has a need for that particular combination of operations, the black squares don't seem like an expected result. Is it a bug, or have I overlooked something?
Code: Select all
magick logo:[400x] -alpha set +noise poisson -modulate 100 -blur 0x1 noise_poisson.pngIf I omit "-alpha set", the output image is all black.
If I use "+noise" with any types other than "poisson", the issue doesn't occur.
If I omit either the "-modulate" or "-blur", the black squares won't be there. If I switch their order by putting the "-blur" before the "-modulate", the squares don't appear. It doesn't seem to matter what modulate settings I use. The squares do appear with blur settings other than "0x1", including "0x0", but will be different sizes of small black squares depending.
I can easily avoid using this construct for my purposes, but if someone has a need for that particular combination of operations, the black squares don't seem like an expected result. Is it a bug, or have I overlooked something?