GDI+ and 48-bit images

GDI+ is high-level graphics library which uses standard GDI windows resources. Only 8 bpp images can be drawn in Windows, and I never heard that it will be changed.
If you want to show images with more than 8 bpp in the Windows platform, you need to convert them first loosing image resolution.

This question has been abandoned. I will make a recommendation to the moderators on its resolution in a week or two. I appreciate any comments that would help me to make a recommendation.

In the absence of responses, I may recommend DELETE unless it is clear to me that it has value as a PAQ. Silence = you don't care

PLEASE DO NOT ACCEPT THIS COMMENT AS AN ANSWER!

Udil
EE Cleanup Volunteer

I do think that my response is worth saving. I don't know why jimrwilson never bothered to respond.

Alf

It's possible that my recommendation will be to accept your answer.
The guidance for my recommendation is in https://www.experts-exchange.com/help/cleanup.jsp.

Udil
EE Cleanup Volunteer

udil, I got a number of notifications from your cleanup work. In all of them you suggest to delete the question without accepting of the answers. Other EE moderators usually pick one of the answers to accept if there are no objections. In this particular case, I tnink, Salte deserves these points. There was a number of questions where I think points should be mine, but I don't want to fight for them in each question.
I hope it is not a new EE policy to deltete all questions without accepting the answers - this may be done programmatically. Please review your approach and try choose the best answer if it is possible. Thanks.

AlexFM,

I'm sorry if I was misunderstood. The policy has not been changed, I just send a message prior to the ordinary recommendation message, in order to get help in making the recommendation. If there are places where you think the points should be yours, please don't hesitate to send a comment claiming that.

Udil
EE Cleanup Volunteer

I just want to say that if you see the best question, please suggest to accept it. At least, other EE moderators do this. According to your profile, you are good in C++, so I beleive it is not a problem for you. Thank you.

>> see the best question

You mean: best answer. :)

>> please suggest to accept it

Will do.


Udil
EE Cleanup Volunteer

Thanks for the reply, Salte.
After further investigation, I see that you are right- GDI and GDI+ do not directly display 16-bit images.  DIB's must be shifted down to 8 bits per color (channel) before the GDI will display them.  We do work with the full 16-bits per channel of information, as this provides better accuracy after image manipulation (rotation, color and gamma correction, scaling, etc.)  We ended up doing a lot of our own routines, as well as a specialized library that is now a bit outdated.

Jim

PNG support 48 bit colors and if you display PNG on windows it will automatically have to scale down the color depth. If you want to keep 48 bit colors you can store your images as PNG on disk and then if and when you port to a windowing system or a future version of windows GDI support 48 bit images you already have them and don't need to do anything. All, you have to do is make sure you have a PNG loader for windows ;)

Alf