Possible bug when defining a new ColorSpace

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pablobhz
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Possible bug when defining a new ColorSpace

Post by pablobhz » 2017-04-09T21:25:40-07:00

Hello everyone. I've noted this today.
When you set the ColorSpace to CMYK, you expect the channels to be "Cyan, Magenta, Yellow, Black".

However, it isn't being that way. I attached an screenshot, where channels can be clearly see as "Cyan , Green , Blue, Black".
Even when i set the ColorSpace to sRGB , the channels available are "Cyan, Green, Blue".

Image
On the screenshot above, i defined the ColorSpace as CMYK
Edit
Version: MagickNET-Q16-x64 v7.0.5.501

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fmw42
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Re: Possible bug when defining a new ColorSpace

Post by fmw42 » 2017-04-09T23:25:03-07:00

Use -colorspace CMYK not -set colorspace CMYK . But to be sure we understand what you are trying to do, please provide your command line.

I have moved this post to the Magick.Net forum since it is most likely an issue of command syntax.

pablobhz
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Re: Possible bug when defining a new ColorSpace

Post by pablobhz » 2017-04-09T23:31:44-07:00

The syntax is correct.

Code: Select all

using (MagickImage testImage = new MagickImage(@"C:\inputfolder\testimage.png"))
            {
                testImage.ColorSpace = ColorSpace.CMYK;
            }
I'm not using the command line interface, i'm using the .NET Wrapper.

After set the ColorSpace to CMYK, when i try to access the channels they aren't being set plus appear like "Cyan , Green , Blue, Black"(instead of the CMYK).

snibgo
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Re: Possible bug when defining a new ColorSpace

Post by snibgo » 2017-04-10T07:46:58-07:00

Where has that screenshot come from? Perhaps that program is the one that has a bug.
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pablobhz
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Re: Possible bug when defining a new ColorSpace

Post by pablobhz » 2017-04-10T07:47:56-07:00

The screenshot came from Visual Studio 2015 (Community Edition, Free)

snibgo
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Re: Possible bug when defining a new ColorSpace

Post by snibgo » 2017-04-10T18:20:56-07:00

As far as I know, IM doesn't write channel names "red", "cyan" etc into files. It writes colorspaces (sRGB, Lab, CMYK etc) into files, and programs such as IM's "identify" then expand these into channel names.

I suggest you try identify and exiftool on your file. You might also try a binary search in the file for those strings.
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pablobhz
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Re: Possible bug when defining a new ColorSpace

Post by pablobhz » 2017-04-10T18:25:07-07:00

Let me see if i got it correctly.

My goal: After set the image ColorSpace to CMYK , set the channels individually on the image. IM won't do that ?
Ex:
1 - Set the image colorspace to CMYK
2 - On some pixels , i want C(0), M(0.3), Y(0.1), K(0)

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fmw42
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Re: Possible bug when defining a new ColorSpace

Post by fmw42 » 2017-04-10T18:52:20-07:00

I would suggest you change the pixel values in the individual grayscale images first, then combine into CMYK colorspace.

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Re: Possible bug when defining a new ColorSpace

Post by pablobhz » 2017-04-11T08:00:46-07:00

A grayscale image has only one channel. I need to change the values on a rGB scale or CMYK scale.
I got an method that uses unsafe code (pointers to the memory) for doing that ; however, it's still slow for doing all the stuff. I think MagickNET can be faster.

Should i delete this topic, since it isn't about an bug or something ?

snibgo
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Re: Possible bug when defining a new ColorSpace

Post by snibgo » 2017-04-11T08:43:15-07:00

Don't delete it.

If you have a usage question, please start a new thread.
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