Image DLL

I thought also that it wasn't possible but I made a WEB-DLL once and with that one it was possible to use the CONTENTTYPE to make it an image.

Reading an JPEG, GIF or BMP isn't the problem.
I already have an DLL that makes an conversion but it would be beautifull when the DLL can become an image.

why do you want to put it in a dll?  c++b can already read/write jpeg files and do the conversion to/from bmp.  if you want to hide the image, just rename it to image.dll or something like that

-- ba

smitty1276,
>> but it would be beautifull when the DLL can become an image.

This makes no sense whatsoever.

I can think of no valid reason to convert an image file (like, a photograph of your pet dog) into an executable program file (like a DLL).  Try to explain what you want to do in clearer terms.

-- Dan

That wasn't me... I dunno what he means either.  We told him about a bunch of DLLs that will load/convert images... beyond that I have no idea what he is talking about... UNLESS...

You can add images to your project as resources, which will be compiled into your executable... is that what you mean, mddebont?

Reading your question, it sounds like exactly what I told you to do... except for the "DLL is an image" part.  I don't get that.

If you want a library (DLL) that will load one format and save to another...

With your ImageMan control...

ImgMan.Picture = "whatever.jpg";
ImgMan.SaveAs = "whatever.bmp";


With DevIL it is pretty much the same thing, but in a more procedural construct.

Sorry smitty1276.  My last comment was meant to be addressed to mkdebont.  -- Dan

Ok, I will try to explain what I want with a little code:
ImgMan.Picture = 'jpeg2bmp.dll?picture=c:\temp\photo.jpg';

So when I get a JPEG image I want to "give" it to the DLL (or what so ever), so that the DLL can become a image of the BITMAP format.

Otherwise I have to do:
jpeg2bmp.loadjpeg('c:\temp\photo.jpg');
jpeg2bmp.savebmp('c:\temp\photo.bmp');
ImgMan.Picture = 'c:\temp\photo.bmp';

This can also, but I was wondering if the first statement was also possible

It is likely that you can just convert the file and return the converted result directly from memory... but it would depend upon the functions that are available with the jpg2bmp object.  Where did you get that?  Is there any documentation?

-- Dan

No there is no documentation.
I just said how I would like it to have...

   jpeg2bmp.loadjpeg('c:\temp\photo.jpg');
    jpeg2bmp.savebmp('c:\temp\photo.bmp');
    ImgMan.Picture = 'c:\temp\photo.bmp';

actually, with c++b, even this is not needed.  you can just load the jpg to a TJPEGImage and convert it to bmp in memory via memory streams.  furthermore, borland's TImage and alike can actually handle jpeg images directly ( you need to include the jpeg header ) so if all you want to do is to load the image and show it, then you don't even need such conversions

-- ba

I think you are confused as to what a DLL is.  A DLL is a Dynamic Link LIBRARY... it is executable CODE.  An bitmap image is a string of unsigned bytes that represent RGB values for each pixel.

That's sort of like saying: "I want to convert a cassette tape to a compact disc (which is obviously very do-able), and then "give" the compact disc to the CD player so that the CD player can become a compact disc."

You understand our confusion?

If you just want to use an object type exported from a DLL to load an image, then all of the suggestions that we have given you will do exactly that.

>> but it would be beautifull when the DLL can become an image.

A little known fact about files sitting on an NTFS partition is that they have have multiple streams! Bear with me on this, and follow this example:

echo "Hello Experts" > C:\Streams.txt
more C:\Streams.txt

You see what you expect to see!

However:

echo "Contained Image" >> C:\Streams.txt:ContainedImage
more C:\Streams.txt

will only produce "Hello Experts".

But:

more C:Streams.txt:ContainedImage

yields "Contained Image".


It's almost as if there are two [disparate] files contained within the same file! And there are. And they can be treated as such.

However, most of today's applications do not support this very well.

[Note that I had to open a command prompt just to show this in operation]

I guess a dll can have a data section just like a jpeg has.

What you will have to do is find the exact format of a jpeg like you would a bitmap.
A bitmap uses a BITMAPINFOHEADER structure and I believe a RGB quad structure.

Anyway I am sure there is some posting somewhere that would give you the details.
I would try a group like (I forget something like IJG JPEG).

My guess if you where going to create a jpeg like that, that it should also have methods to read itself.

But this is where it gets a little strange. Does the dll read itself upon initiation and if so does it also know how
to display itself as well?

When the dll is created is that the time that the pixels get read and established. Or do you hard code the values
in some static memory of the dll? Will the dll read from a file?

There are also other considerations. One for example is which jpeg format to use. The lossless one I guess is supposed to
be the best.

I dont really understand the purpose of this dll/image.

What it seems like you need to me is just a dll that hands back a hbitmap handle from reading a jpeg file.

The posting I sent to you before does just that. And so many more types of image file formats it's un-believable.
http://www.imagemagick.com

With image magick you could do something like this.

Image image;
image.read(FileName); //FileName could be any of 50 different file formats for windows.
image.magick("BMP"); //variable image now contains the jpeg info in bitmap form.

RJSoft