Re: Create compatible bitmap - C / C++ / MFC Discussion Boards

From "CreateDIBSection Function"[^] documentation:

iUsage [in]
The type of data contained in the bmiColors array member of the BITMAPINFO structure pointed to by pbmi (either logical palette indexes or literal RGB values). The following values are defined.

Value Meaning
DIB_PAL_COLORS
The bmiColors member is an array of 16-bit indexes into the logical palette of the device context specified by hdc.
DIB_RGB_COLORS
The BITMAPINFO structure contains an array of literal RGB values.

Where's your array?
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

modified on Friday, November 19, 2010 7:50 AM

I'd say it's not there... Wink | ;)

lpInfo->bmiColors[0].rgbBlue=1;
lpInfo->bmiColors[0].rgbGreen=1;
lpInfo->bmiColors[0].rgbRed=1;
lpInfo->bmiColors[0].rgbReserved=0;

... is what I tried. I also iterated over 256 array indices, assigning 1 or 0. Which values do I have to assign? The blitted image looks different, but still more like a "pixel color accident".

Mac

It really depends on your DIB bits (of course you've to assign the whole array).
My naive attempt, would be:

C++

  for (int n=0; n < 256; n++)
  {
    lpInfo->bmiColors[n].rgbBlue=b;
    lpInfo->bmiColors[n].rgbGreen=b;
    lpInfo->bmiColors[n].rgbRed=b;
    lpInfo->bmiColors[n].rgbReserved=0;
    lpInfo->bmiColors[n].rgbBlue=n;
    lpInfo->bmiColors[n].rgbGreen=n;
    lpInfo->bmiColors[n].rgbRed=n;
    lpInfo->bmiColors[n].rgbReserved=0;
  }

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

modified on Tuesday, November 23, 2010 7:47 AM

When I do that, I run into an assertion (at some random point in my application), and in addition I sometimes get an "Out of memory" message.
When I assign only [0] through [9] of the array, I do get a blitted image like described in my original post, but with a very redish touch.

Mac

Pardon my dumb question: Do you know you should allocate enough memory for the array?
i.e.

BITMAPINFO *lpInfo = (BITMAPINFO *) (new BYTE[sizeof(BITMAPINFO) + 255 * sizeof(RGBQUAD)]);

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

The "dumb" part was on my side, because I didn't allocate any memory. But even though now I don't get an exception anymore, the result is still the same as described on my previous posts.

Mac

Possibly you should have a look at the palette of the image file (the one you use for the 'unusual approach'). How is the palette defined (i.e. what is the RGBQUAD array content?)

Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

That was exactly what I tried, when I found the "unusual approach": What is different in the RGBQUAD, in the BITMAPHEADER, in the BITMAPINFO if I load the bitmap from the file? You know - so I could assign the exact same properties to my bitmap created with CreateDIBSection. The problem is, I didn't find a way of accessing any of the mentioned structures. The only thing I was able to find out after using LoadImage() was this (also see code from original post):

BITMAP bm;
cBmp.GetBitmap(&bm);

bm was then filled with these values

bmType 0 long
bmWidth 320 long
bmHeight 180 long
bmWidthBytes 320 long
bmPlanes 1 unsigned short
bmBitsPixel 8 unsigned short
bmBits 0x07a10000 void *

No surprise there. I assigned the same values (bmPlanes, bmBitsPixel etc.) to BITMAPINFO *lpInfo (also see original post).
Is there a way of retrieving a "proper" BITMAPINFO or BITMAPINFOHEADER from the bitmap loaded with LoadImage()?

Mac

MacCPlus wrote:
Is there a way of retrieving a "proper" BITMAPINFO or BITMAPINFOHEADER from the bitmap loaded with LoadImage()?

No, I suppose. Anyway you may retrieve these structures loading the file yourself (see, for instance here - it looks a bit dated, but, at the moment I cannot find an up-to-date one).
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

I got it!

Had to initialize bmiColors like this:

for (int n=0; n < 256; n++)
{
    m_pBitmapInfo->bmiColors[n].rgbBlue=n;
    m_pBitmapInfo->bmiColors[n].rgbGreen=n;
    m_pBitmapInfo->bmiColors[n].rgbRed=n;
    m_pBitmapInfo->bmiColors[n].rgbReserved=0;
}

Thanks for the advice!
Mac

It was what I intended here, since they are grey gradations, unfortunately (now I realize) I made a typo (fixed now).
Sorry for the inconvenience.
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

Actually, I should have realized that myself reading your first response. But I guess I wasn't quite "there" yet. Wink | ;)

I found out how the color table is supposed to look like by debugging bmiColors[] after having loaded said bitmap file using the code you posted.

Mac

Hi!
I have developed a MFC Dialog based application, that consists of buttons, combo-boxes, edit box and a button to browse for a file etc, Now i want a free tool, through which i can repeatedly automate/test my app without the involvement of human. so is there asny such free tool in which initially i will show the cursor flow on my app, then the tool will proceed to do the same for required number of times. i searched thru net, i got few like AutoHotkey and winspy ++, but they require some scripts to be written, is there any software (free) which can be used without writing scripts!!

Thanks!

See here for ideas.

"One man's wage rise is another man's price increase." - Harold Wilson

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"Man who follows car will be exhausted." - Confucius

Hello Friends

I am using LoadImage to load bitmap but how can I load Tiff File?

Any Ideas?
Thanks & Regards
Yogesh

GDI+ won't do it for you. You could look for another library that does; I'm pretty sure GIMP does. Or you could create your own TIFF package. IIRC there might be some licensing issues.

Smile | :)

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

Luc Pattyn wrote:
GDI+ won't do it for you.

GDI+ has built-in encoders and decoders that support the following file types:

BMP
GIF
JPEG
PNG
TIFF

GDI+ reference: "Using Image Encoders and Decoders"[^].
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

I stand corrected; I don't see what the OP's problem is then.

Smile | :)

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

Are you going to update CP Vanity? I can't leave without.
Plz plz... Big Grin | :-D

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

There probably will be a CP Vanity 2.0 pretty soon after we get a useful web service; there still is hope, it was discussed yesterday.

And why do people insist on discussing CP Vanity everywhere except where it should be discussed, in the article's forum?

Smile | :)

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

I stand corrected.
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

BTW: you did see the CP Vanity Lite article by Nish yesterday?

Smile | :)

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

Nope, it is pretty good (Nish rocks): thank you for signaling.
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

modified on Friday, November 19, 2010 3:10 PM

See CxImage's CxImageTIF[^] class.

-Sarath.

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hello guys..I read somewhere that callback function works better than the WM_TIMER in vc6. So I tried following code but it does't work. whats wrong with it?

BOOL CTimers_CallbackFuncDlg::OnInitDialog()
{
     ..........
     ..........
     //set the first timer
     SetTimer(ID_CLOCK_TIMER,1000,(CALLBACK)&Timer1); //address of the function passed, i also tried without writing CALLBACK
     ..........
}

void CALLBACK CTimers_CallbackFuncDlg::Timer1()//i also tried without writing CALLBACK in function signature
{
	//get current time
	CTime curTime = curTime.GetCurrentTime();

	//format the label and display the time
        m_sTime.Format("%d:%d:%d",curTime.GetHour(),curTime.GetMinute(),curTime.GetSecond()); //m_sTime = variable added using class wizard (to label)

	UpdateData(FALSE);
}

a syntax error is given saying error C2059: syntax error : '__stdcall'