I have a problem with single channel images. I sucessfully create a single channel image and load with data. But when i want to show this image with g.drawImage function, i don’t see anything. I don’t know what is the problem.
How the Juce handle the single channel images? Any idea?
Thanks for the answers.
Hmm, they should be drawn using the current colour… Which OS is this? Got a piece of sample code that fails?
(But before I look into this, please check that it really is a problem with the image type by trying the same thing with ARGB. You could just be drawing it off-screen or something)
The OS is Windows 7, with visual C++ 2008 and Juce 1.50.
When i use Image::ARGB as pixel format, it works well.
I create a single channel image:
juce::Image* testImage = new Image(juce::Image::SingleChannel, imageProcessor->getImageWidth(),imageProcessor->getImageHeight(), true);
And after that i dont really know how can i load this image with simple uint8 values.
I tried to create bitmapdata as:
Image::BitmapData bd(*testImage , 0, 0, testImage ->getWidth(), testImage ->getHeight(), true);
and after that i doing this
for(int i = 0; i < testImage ->getWidth() * testImage ->getHeight(); ++i)
bd.data[i] = 128;
it should be a gray color image in single channel.
Propably this is the problem, because the drawimgae function works well if i use ARGB or RGB pixel format.
Could you explain, how the juce handle the single channel pixelformat? I didn’t found to much about that in the refernce.
So juce 1.50 couldn’t handle single channel image format. I see.
The new version of juce handle this? I think yes. One more question.
If i use the latest version, the imge fill, what i wrote to set pixel values, is it correct?
Well, the BitmapData class has changed since then, but essentially, yes.
[quote=“Arpad”]I have a problem with single channel images. I sucessfully create a single channel image and load with data. But when i want to show this image with g.drawImage function, i don’t see anything. I don’t know what is the problem.
How the Juce handle the single channel images? Any idea?[/quote]
The only meaningful way to “display” a single channel image is to fill with the current brush. Typically a solid color. Set the brush then call Graphics::drawImageAt with fillAlphaChannelWithCurrentBrush set to true.
Of course you should be on the most recent JUCE.