Loading images that aren't BMP...

yaya · 11-15-2009, 04:35 PM

I'm looking for a way to load other image formats such as PNG, JPEG, DDS, etc, and use them like you can with BMP files (ie use with Win32 functions). For example, how could I load a PNG file into a HBITMAP structure?

I have looked at libpng.org: top level, but that seems to only do PNG files and I'm not sure if it can turn it into a HBITMAP. Anyone know anything about this?

Thanks.

novacain · 11-15-2009, 06:28 PM

Have you looked at GDI+ (GDIPlus)?

MFC CImage or .NET C# Graphics objects will handle most formats, inc. jpg and pgn (IIRC).

yaya · 11-15-2009, 07:57 PM

Sorry, I forgot to mention, I'm just using C/C++ Win32, no MFC. I haven't done much in the way of the GDI... so this can do it without too much trouble?

novacain · 11-17-2009, 10:21 PM

GDI won't work without a 3rd party library (need GDI+ or .NET).

You didn't mention your IDE/complier.

In MSVC you could write a MFC dll to convert the images and call it from your WIN32 app.

This dll would be very simple, follow the MFC wiz and create a DLL (static link the MFC libs), then export the following function to get the HBITMAP.

Code:

#include <atlimage.h>		// CImage 
#define DLLExport   __declspec (dllexport) //dllimport in app

//error checking required
DLLExport HBITMAP ConvertImage(char *szFullpath)
{
        CString sFullpath(szFullpath);
        CImage Image;
        
        Image.Load(sFullpath);
        return Image.Detach();
}

yaya · 11-18-2009, 01:33 AM

Ah, I see. I'll look into this and give it a go soon. Thanks.

abachler · 11-18-2009, 02:30 PM

You can also use something like cximage, and convert the image in memory to a bmp which you then blit into the HBITMAP.

Alex31 · 11-19-2009, 06:33 AM

You don't need any external library (never on Windows)
GDI+ manages all imaginable formats.
JPEG and others are also native with COM or Shell apis.

novacain · 11-19-2009, 07:24 PM

Quote:

Originally Posted by Alex31

You don't need any external library (never on Windows)
GDI+ manages all imaginable formats.
JPEG and others are also native with COM or Shell apis.

If you bothered to read the thread you would have noticed that I already pointed that out in the second post.

You may have also noticed that GDI (without the '+') will only handle BMPs (and so WILL require a 3rd party lib).

Please try to keep up....

iMalc · 11-20-2009, 12:52 AM

I recommend using OleLoadPicture on Windows. Here's some sample code that uses it.
CodeProject: Rendering GIF, JPEG, Icon, or Bitmap Files with OleLoadPicture. Free source code and programming help

11-15-2009, 04:35 PM	#1
yaya Not stupid, just stupider Join Date: May 2007 Location: Earthland Posts: 182	Loading images that aren't BMP... I'm looking for a way to load other image formats such as PNG, JPEG, DDS, etc, and use them like you can with BMP files (ie use with Win32 functions). For example, how could I load a PNG file into a HBITMAP structure? I have looked at libpng.org: top level, but that seems to only do PNG files and I'm not sure if it can turn it into a HBITMAP. Anyone know anything about this? Thanks.
yaya is offline

11-15-2009, 06:28 PM	#2
novacain train spotter Join Date: Aug 2001 Location: near a computer Posts: 3,451	Have you looked at GDI+ (GDIPlus)? MFC CImage or .NET C# Graphics objects will handle most formats, inc. jpg and pgn (IIRC). __________________ "Man alone suffers so excruciatingly in the world that he was compelled to invent laughter." Friedrich Nietzsche "I spent a lot of my money on booze, birds and fast cars......the rest I squandered." George Best "If you are going through hell....keep going." Winston Churchill
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11-15-2009, 07:57 PM	#3
yaya Not stupid, just stupider Join Date: May 2007 Location: Earthland Posts: 182	Sorry, I forgot to mention, I'm just using C/C++ Win32, no MFC. I haven't done much in the way of the GDI... so this can do it without too much trouble?
yaya is offline

11-17-2009, 10:21 PM	#4
novacain train spotter Join Date: Aug 2001 Location: near a computer Posts: 3,451	GDI won't work without a 3rd party library (need GDI+ or .NET). You didn't mention your IDE/complier. In MSVC you could write a MFC dll to convert the images and call it from your WIN32 app. This dll would be very simple, follow the MFC wiz and create a DLL (static link the MFC libs), then export the following function to get the HBITMAP. Code: #include <atlimage.h> // CImage #define DLLExport __declspec (dllexport) //dllimport in app //error checking required DLLExport HBITMAP ConvertImage(char *szFullpath) { CString sFullpath(szFullpath); CImage Image; Image.Load(sFullpath); return Image.Detach(); } __________________ "Man alone suffers so excruciatingly in the world that he was compelled to invent laughter." Friedrich Nietzsche "I spent a lot of my money on booze, birds and fast cars......the rest I squandered." George Best "If you are going through hell....keep going." Winston Churchill
novacain is offline

11-18-2009, 01:33 AM	#5
yaya Not stupid, just stupider Join Date: May 2007 Location: Earthland Posts: 182	Ah, I see. I'll look into this and give it a go soon. Thanks.
yaya is offline

11-18-2009, 02:30 PM	#6
abachler Malum in se Join Date: Apr 2007 Posts: 3,188	You can also use something like cximage, and convert the image in memory to a bmp which you then blit into the HBITMAP. __________________ Until you can build a working general purpose reprogrammable computer out of basic components from radio shack, you are not fit to call yourself a programmer in my presence. This is cwhizard, signing off.
abachler is offline

11-19-2009, 06:33 AM	#7
Alex31 Registered User Join Date: Apr 2007 Posts: 136	You don't need any external library (never on Windows) GDI+ manages all imaginable formats. JPEG and others are also native with COM or Shell apis.
Alex31 is offline

11-20-2009, 12:52 AM	#9
iMalc Algorithm Dissector Join Date: Dec 2005 Location: New Zealand Posts: 2,741	I recommend using OleLoadPicture on Windows. Here's some sample code that uses it. CodeProject: Rendering GIF, JPEG, Icon, or Bitmap Files with OleLoadPicture. Free source code and programming help __________________ My homepage Advice: Take only as directed - If symptoms persist, please see your debugger
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