[SOLVED] How to access pixel values in 16bit Grayscale TIF?

[pmh4514]

I have a 16bit grayscale TIF file which I load from disc into a QImage.

Ultimately for display I will use QPixmap which is going to resample it to 8 bits, but first I want to calculate a histogram (and possibly adjust) before the 8bit downsample for display.

This seems like it should be a simple question, but how do I access the 16bit grayscale pixel values (ie. the value between 0 and 65,536)? I know I can access myImg.pixel(x,y) for any coordinate, but that only returns a QRgb.

Or am I misunderstanding QRgb?

Thanks!

[SGaist]

Hi,

AFAIK, QImage doesn't support 16bit images yet (might be in the future, if someone implements it)

What you can do however is use a library like OpenCV for this kind of mathematics.

Hope it helps

[pmh4514]

ahh ok so the 8bit downsampling is happening the instant I load the QImage from disc? I'll try OpenCV, thanks

[pmh4514]

Yes, OpenCV worked much better. thanks!

[Tchernio]

I need to load and process 16bt tiff image with full scale using QImage. From what I read there are no any activities on that front.

If this is going to happen in the distant future I probably would need to get OpenCV and using it instead Qt

[SGaist]

Hi and welcome to devnet,

For 16bit tiff images processing you should rather use OpenCV