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Hi,
i get a 32 bit RGBA Image from my firewire camera...and i want to display a gray scale image to a Picture Control with MFC!
convert function:
<br />
void CImageProcView::RGBA2Gray(char *Img1, char *Img2, unsigned int ByteSize)<br />
{<br />
for(int i = 0; i<ByteSize/4; i++)<br />
{<br />
Img2[i]=((signed char)Img1[4*i]+(signed char)Img1[4*i+1]+(signed char)Img1[4*i+2])/3;<br />
}<br />
}<br />
<br />
char *CurrentImage;<br />
char *GrayMap;<br />
CStatic m_Img1;<br />
CBitmap Bitmap1;<br />
memcpy(Current,FireCapture->FlippedBuffer,FireCapture->grabBufferSize);<br />
<br />
RGBA2Gray(CurrentImage, GrayMap, FireCapture->grabBufferSize);
<br />
Bitmap1.CreateBitmap(FireCapture->pVih->bmiHeader.biWidth, FireCapture->pVih->bmiHeader.biHeight, 1, 8, GrayMap);<br />
<br />
m_Img1.SetBitmap(Bitmap1);<br />
somthing dont work with this CStatic Picture Control;/ any idea? i think the CreateBitmap dont take the cBitsPerPel;/
bye
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Only about the algorithm:
surfman19 wrote: void CImageProcView::RGBA2Gray(char *Img1, char *Img2, unsigned int ByteSize)
{
for(int i = 0; i {
Img2[i]=((signed char)Img1[4*i]+(signed char)Img1[4*i+1]+(signed char)Img1[4*i+2])/3;
}
}
I think that this will generate some overflows, I like more this:
Img2[i]=signed char(((int)Img1[4*i]+(int)Img1[4*i+1]+(int)Img1[4*i+2])/3);
and why signed? Is it better using unsigned char/int ?
bye
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<br />
the output of the camera is a RGBA32 image!<br />
<br />
CStatic m_Img1;<br />
unsigned char *ActImage;<br />
unsigned char *GrayMap;<br />
<br />
ActImage = new unsigned char[FireCapture->grabBufferSize];<br />
GrayMap = new unsigned char[FireCapture->grabBufferSize];<br />
<br />
memcpy(ActImage,FireCapture->FlippedBuffer,FireCapture->grabBufferSize);<br />
RGB2Gray(ActImage, GrayMap, FireCapture->grabBufferSize);<br />
<br />
Bitmap1.CreateBitmap(FireCapture->pVih->bmiHeader.biWidth, FireCapture->pVih->bmiHeader.biHeight,<br />
1,8,GrayMap);<br />
m_Img1.SetBitmap(Bitmap1);<br />
<br />
<br />
<br />
<br />
void CImageProcView::RGB2Gray(unsigned char *Img1, unsigned char *Img2, unsigned int ByteSize)<br />
{<br />
for(int i = 0; i<ByteSize/4; i++)<br />
{<br />
Img2[i] = ((char)Img1[4*i] + (char)Img1[4*i+1] + (char)Img1[4*i+2]) / 3;<br />
}<br />
}<br />
why could the CStatic dont display the grayscale image????hm;/
cu
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Your loop is already wrong. Img2 is an unsigned char *, so Img2[0] refers to byte 0, Img2[1] refers to byte 1, etc. And you should be creating your bitmap using CreateDIBitmap().
void CImageProcView::RGB2Gray(unsigned char *Img1, unsigned char *Img2, unsigned int ByteSize)
{
for(int i = 0; i<ByteSize/4; i++)
{
Img2[i] = ((char)Img1[4*i] + (char)Img1[4*i+1] + (char)Img1[4*i+2]) / 3;
}
}
If you find it difficult to think in terms of bytes, you can always cast it to RGBQUAD.
void CImageProcView::RGB2Gray(unsigned char *Img1, unsigned char *Img2, unsigned int ByteSize)
{
RGBQUAD *pSource = static_cast<RGBQUAD*>(Img1);
RGBQUAD *pDest = static_cast<RGBQUAD*>(Img2);
for(int i = 0; i<ByteSize/sizeof(RGBQUAD); i++)
{
pDest[i].rgbRed = pDest[i].rgbGreen = pDest[i].rgbBlue = (pSource[i].rgbBlue + pSource[i].rgbGreen + pSource[i].rgbRed) / 3;
pDest[i].rgbReserved = 0;
}
}
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<br />
RGBQUAD *pSource = static_cast(Img1);<br />
static cast need a type to cast!! do you mean static_cast<RGBQUAD>(Img1); ?<br />
<br />
i always get a error C2440: 'static_cast' : cannot convert from 'unsigned char *' to 'RGBQUAD'<br />
your grayscale is now 32 bit right? cant i use 8 bit?
cu
-- modified at 6:28 Friday 12th May, 2006
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So I forgot that pre eats up the < and >. Can't you guess that it's supposed to be static_cast<RGBQUAD*>(Img1)?
You can choose to use 8-bit but I didn't see you set your palette.
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<br />
error C2440: 'static_cast' : cannot convert from 'unsigned char *' to 'RGBQUAD *'<br />
Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast<br />
<br />
<br />
RGB2Gray(ActImage, GrayMap, FireCapture->grabBufferSize);<br />
<br />
how can i set a palette in my case and display the grayscale image?<br />
cu
-- modified at 11:29 Friday 12th May, 2006
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Hi
I have i combobox with dropdownlist style ( and ownerdrawfixed | havestrings)
am filling it using addstring method
how can i get the text of an item in the drawitem method?
thanks alot
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if you use WM_DRAWITEM
maybe it is some helpful to you
CString str;
GetLBText(lpDrawItem->itemID, str);
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thanks alot it worked fine in drawitem method after testing that the itemid is in the valid range of indices.
but the items seems so close to each other, how can this be solved?
and how can i remove the border from the edit area of the combo?
again thanks alot for your help
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like this only enter numbers in combobox
<br />
COMBOBOXINFO m_info;<br />
ZeroMemory(&m_info, sizeof(COMBOBOXINFO));<br />
m_info.cbSize = sizeof(COMBOBOXINFO);<br />
m_Combo.GetComboBoxInfo(&m_info);<br />
<br />
ModifyStyle(m_info.hwndItem,0,ES_NUMBER,0);<br />
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Hi there,
I have a program that uses couple of sockets to communicate with two different devices. I have a socket class that supports both UDP and TCP (and Srever and client). I use INI file to specify what socket to use for every application. For the incomming messages in my code's enterance where I need to receive data from different clients, works for UDP socket but does not work for TCP.
Can any one tell me what could be the problem?
The following shows a part of my INI file for UDP socket. what changes should I make for the TCP one?
[DataLink Socket]
CfgTCP=TCP
CfgServer=TRUE
CfgLocalPort=1250
CfgRemotePort=1250
CfgRemoteAddr=127.0.0.1
CfgLocalAddr=127.0.0.1
CfgSrvMaxConnLimit=10
CfgCommType=BOTH
CfgKeepSockOpen=TRUE
Appreciate your help,
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Hi
Please search on code project for examples
KK
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hello all
I need to find a red " + " in a image and i want a good algorithm .
thank you
-- modified at 9:48 Thursday 11th May, 2006
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hello
I have a image , and a red plus is in it , and Iwant to find it's X and Y.
and I want a algorithm .
thanks a lot
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if it is a bmp, then i think you could go though each pixel and test the pixel around like this (i'm not an expert of image computing, so i could be wrong) :
for each vertical line -> 'y' coordinate
for each pixel in the line -> 'x' coordinate
if pixel color is red then
if pixel directly on top is red and
pixel directly at left is red and
pixel directly at right is red and
pixed directly at bottom is red then
you found the plus symbol, which coordinates are (x; y)
end if
end if
end for
end for
TOXCCT >>> GEII power
[VisualCalc 3.0 updated ][Flags Beginner's Guide new! ]
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I know this way but it is a lot of noise in image and the plus isn't like this :
------------o--------
-----------ooo-------
------------o--------
it is like this :
-----------------------o-----------
-----------------------o-----------
-----------------------o-----------
---------------o o o o O --- o o o o
---------------------o------------
----------------------o-----------
----------------------o-----------
----------------------o-----------
and the most important is that it may rotate . and i dont want to rotate it in a ( for ) I want it to be a speedy algorithm . and i also want to use the long tail of plus , I mean it isn't one pixel .
thanks
-- modified at 10:19 Thursday 11th May, 2006
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To find something like that I recommed correlation.
When you find your first red pixel, you sum the multiplication of all of the pixels in your defined "plus" with the ones in the appropriate location in the image. Since your image is noisy your defined "plus" needs to be thicker than a single pixel width. Once you get a total sum that exceeds a specified threshold, you declare that a "plus" has been found.
Since you have to deal with rotations, the appropriate locations for the multiplies will have to be computed taking different rotations into account. This will increase your processing time significantly. To reduce the number of iterations, once you find the first pixel you know that all other pixels will be right or down from there, assuming the origin is in the top left corner.
-- modified at 10:29 Thursday 11th May, 2006
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You can use 2D-fft (or 2D convolution/correlation).
It will work also if there is a rotation on the plus (i.e. there is only a phase rotation) or if there is a scale factor (i.e. the ratio between frequency amplitudes remains constant),.....
but they aren't
V_shr wrote: speedy algorithm
If you want a good and fast way ,probally, your work will be very hard!
Try also something using some pre-processing operation, like noise filters and/or colors thresholds(-> RED plus)
Hope it helps
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_Russell_ wrote: Try also something using some pre-processing operation, like noise filters and/or colors thresholds(-> RED plus)
Good!
"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow
cheers,
Alok Gupta
VC Forum Q&A :- I/ IV
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I want, I want, I want.
Since this site is not about doing the job for you, but helping you with problems, I will point you in a good direction and wait to see what effort you make.
Search code project for the following types of article
image processing and pattern recognition
Some thoughts to consider are:
1) Are you looking for a specific size red plus or any two crossing lines of any thinkness and any length? It becomes easier if you know the exact size, thinkness of lines and orientation of the "plus"
2) How is the "plus" put on the image. Can it be partly off your image?
For a first cut approach, assuming you know the exact color red (or even the range of colors), try searching through each pixel in your image until you find a red one. Then you need to see if the shape of your plus is in the appropriate adjoining pixels (this is a series of checks over a specific set of offsets from your "found" red pixel. If you get a match, then you have to check some more to make sure that you are not in a field of red.
If your "plus" can be partly off the edge, you will have to compute the remaining portions of the plus and use the approach above with a modified definition of a "plus"
This is brute force. There are probably better ways to do this. But this will get you started.
Good luck.
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