[SOLVED] QImage using pointer to valarray ?

CamelFrog

Hello,

I'm new to this Forum. In the context of loading and visualising scientific images in FITS files, as quick as possible, I am using valarray, used by the CCFITSIO library. The latter reads raw scientific images in these objects. From the QImage doc, and this specific overload :

QImage(uchar * data, int width, int height, Format format)

I understand that QImage could take a pointer to some data in a buffer.

Is there any way to get a pointer to, say, valarray<float> myValArray ? And give it to QImage, without making any intermediate copies ?

At the moment, the compiler (VS2013) does not allow me to use
&myValArray[0] in QImage. I assume this comes from my misunderstanding of either QImage and valArray objects.

Thanks for your help.

SGaist

Hi and welcome to devnet,

QImage doesn't support float AFAIK. You should rather write a QImageReader subclass that decodes your image data in something supported by QImage

CamelFrog

@SGaist
Thank you for your reply.

Then, what should be the type of the array whose pointer can be sent to QImage(uchar *data,...) ?

Thanks

CamelFrog

Does QImage(uchar* data) means necessarily that i can only send char array, with numbers spanning from 0 to 255 ?

Are there other Qt classes that support other types of image arrays that are to be displayed ?

SGaist

It can be something else as long as there's a reader that can translate it in a format QImage understands.

QImage is the base image class, what can be done is to use OpenCV to convert your image data into something QImage can handle

CamelFrog

@SGaist
Ok, I just tried to rescaled my image array within an intensity between 0 to 255 and cast a uchar*, it's working now.

Thanks