Watermarking

Discussions on GFL SDK, the graphic library for reading and writing graphic files

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dominique
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Watermarking

Post by dominique »

Hi GFLSDK programers !

I don't know how to do water marking and if it's difficult to implement.
Should it be possible to add this kind of skill in GFL?

Rgds
Dom
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xnview
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Re: Watermarking

Post by xnview »

You have gflBitBlt :-)
Pierre.
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dominique
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Post by dominique »

Ok, if you told me it's possible using this function, I think I can do what I want as usual ;)
I'll give some news about this.
Dom
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dominique
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Post by dominique »

And what is the difference between gflBitblt and gflBitbltEx ?
Maybe the second one change the alpha channel too ?
I'll search some information about invisible watermarking... if someone knows about this ;)
Dom
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dominique
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Post by dominique »

Ok, I can merge a png with a RGB image using gflBitbltEx.
I try to do the same for greylevel images using gflBitblt and TransparentIndex without success. What is exactly TransparentIndex?
Thx,
Dom
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xnview
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Post by xnview »

TransparentIndex is used as transparent index for picture with colormap
Pierre.
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dominique
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Post by dominique »

Do you have something to do transparency merging with greyscale images?
I wrote something that works fine but I prefer to use gfl functions.
Dom
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dominique
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Post by dominique »

I use gflAddText. I'd like to add transparency to the text.
Is it possible to add this feature using the alpha channel of the text color?
Is there any function to get the text's size given a selected font (gflGetTextRect)?
Rgds
Dom
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dominique
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Post by dominique »

Up for next version :)
Dom