Re: file - C / C++ / MFC Discussion Boards

geo_m16-Sep-04 5:24

16-Sep-04 5:24

Webcams usually provide some sort of web server, that you can download it from there and then you can display it (as jpeg probably)
But without further info, it's difficult to say how can you do it.

wav file resampling

sinha_abhijeet16-Sep-04 0:52

sinha_abhijeet

16-Sep-04 0:52

Hi,
I am new to VC++.
How do I resample(upsample/downsample) any wave file to a predefined value. Basically how do I change the attributes denoted by the WAVEFORMATEX structure, of an already existing file. (for example I have to convert any wav file into 8 khz 16 bit, PCM). The file will be an already existing one and not one to be recorded.
Thanx in advance.

Re: wav file resampling

Alexander ^M.,16-Sep-04 9:49

Alexander ^M.,

16-Sep-04 9:49

It's just a matter of math skills. I'm sorry, but I suggest you first read some articles about that.

Don't try it, just do it! Wink | ;-)

Getting IPv6 address

Alpha Siera16-Sep-04 0:47

Alpha Siera

16-Sep-04 0:47

Hi,

How can I reterive IPv6 address of system. Which API I can use for this.

Thanks for Reply

Regards
Alpha

Re: Getting IPv6 address [modified]

Antony M Kancidrowski16-Sep-04 2:31

Antony M Kancidrowski

16-Sep-04 2:31

Look at getaddrinfo()

in the addrinfo struct there is a sockaddr struct which can have either an ipv4 or ipv6 structure.

Ant.

I'm hard, yet soft.
I'm coloured, yet clear.
I'm fruity and sweet.
I'm jelly, what am I? Muse on it further, I shall return! - David Williams (Little Britain)

Re: Getting IPv6 address [modified]

Alpha Siera16-Sep-04 18:27

Alpha Siera

16-Sep-04 18:27

Hi,

This is ok. But i want to know all adapters which are present in the system along with their IPv6 ip addresses.getaddrinfo is socket call. I have tried IP Helper function GetAdaptersAddresses but I don't know it's not returning me IPv6 address. I am getting all details of adapter but not IP address.

Thanks for reply

Regards
Alpha

file

swarup16-Sep-04 0:46

swarup

16-Sep-04 0:46

hi i want to open an exe as a file in my application. in my dialog box app there is a button when i click on that it will open a exe as a file and search for suppose "t".

how can i open an exe as a file and how to replace a char or string in it.

swarup

Re: file

Paolo Ponzano16-Sep-04 2:23

Paolo Ponzano

16-Sep-04 2:23

I think you use the GetOpenFileName() to open the exe file
the you need an handle in order to open file using CreateFileA

<br />
HANDLE hFile=CreateFile(filename, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, NULL, NULL);<br />

at this point you should have an handle to your exe file, now we read it into memory using ReadFileA

<br />
DWORD BR=0; //numbers of bytes read by readfile<br />
char *tempbuff=(char*)calloc(dFileSize,sizeof(char));<br />
<br />
ReadFile(hFile, tempbuff, dFileSize, &BR, NULL);<br />
<br />
if( BR < dFileSize){<br />
//Process the error, since not all file could have been read<br />
}<br />

now we search the string you're looking for

<br />
char *p=NULL;<br />
p=strstr(tempbuff,"TEXT_TO_BE_SEARCHED");<br />
if( p==NULL) // no TEXT_TO_BE_SEARCHED found in tempbuff<br />
else you've the first occurrence<br />

for writing you do the same using WriteFile,
bye
Paolo

Re: file

swarup18-Sep-04 2:06

swarup

18-Sep-04 2:06

After reading the tempbuff. the size of it is showing as 3. i want to read the whole file.

swarup

Windows .libs

JensB16-Sep-04 0:27

JensB

16-Sep-04 0:27

Hi,

I have some MFC projects which use the following libs:
kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib uuid.lib

Are these libs always necessary for using MFC? How can I know which libs to use and will I get errors compiling/linking when those deleted from the project?

Best regards,
Jens

Re: Windows .libs

geo_m16-Sep-04 5:20

geo_m

16-Sep-04 5:20

They are ignored if not used, if there's a lib missin, you will get an linker error that there's some function missing.

hope that helps

DLL

swarup16-Sep-04 0:03

swarup

16-Sep-04 0:03

HI there
how to create a dll and how to use it can anybody tell me. if i create a dll and dont use a def file does it export a dll.
DLL_API int fnDll(void)
{
return 42;
}

#ifdef DLL_EXPORTS
#define DLL_API __declspec(dllexport)
#else
#define DLL_API __declspec(dllimport)
#endif

and rest of the code.

if i dont use a def file i think i canot export that function. is that so.

swarup

Re: DLL

Paolo Ponzano16-Sep-04 2:31

Paolo Ponzano

16-Sep-04 2:31

declare the funcion you want to export as

<br />
extern "C" __declspec( dllexport) BOOL Function(char *buffer,char *tg);<br />

in your DLL project

In the Project that need the function do

declare in header file

<br />
extern "C" __declspec( dllimport ) BOOL Function(char *buffer,char *tg);<br />

<br />
HANDLE hDLL=LoadLibrary("dllname");<br />
if(hDLL == NULL)<br />
{<br />
//handle error<br />
}<br />
<br />

hope it helps
Paolo

Thread

swarup16-Sep-04 0:00

swarup

16-Sep-04 0:00

hi there

can anybody give a sample or example in how to create a thread and what's it use and how to use it.

swarup

Re: Thread

RChin16-Sep-04 0:23

RChin

16-Sep-04 0:23

This[^] is a very good intro to multi-threaded programming.

I Dream of Absolute Zero

Disable Restart from the windows shutdown dialog box

sirtimid15-Sep-04 23:14

sirtimid

15-Sep-04 23:14

Does anyone know how can I remove the "Restart" and "Log off" options from the shutdown dialog box of the WindowsXP in VC++?

Thanks in advance!

Disable Restart from the windows shutdown dialog box

sirtimid15-Sep-04 23:13

sirtimid

15-Sep-04 23:13

Does anyone know how can I remove the "Restart" and "Log off" options from the shutdown dialog box of the WindowsXP?

Thanks in advance!

Deleting ODBC Datasources

si_6915-Sep-04 23:00

si_69

15-Sep-04 23:00

Hi All

does anyone know how to programatically delete ODBC datasources
or can anyone point me in the right direction ?

thanks

Si Smile | :)

Re: Deleting ODBC Datasources

P-Rex15-Sep-04 23:55

P-Rex

15-Sep-04 23:55

Hi,

You have to delete some keys in the registry.

Look in the registry under [HKEY_LOCAL_MACHINE\SOFTWARE\ODBC\ODBC.INI\].
Delete the Key of your ODBC datasource and the value of your ODBC datasource [HKEY_LOCAL_MACHINE\SOFTWARE\ODBC\ODBC.INI\ODBC Data Sources].

Then should it be removed! Cool | :cool:

Use CRegKey to delete the entries in the registry.

P-Rex

Re: Deleting ODBC Datasources

P-Rex16-Sep-04 0:01

P-Rex

16-Sep-04 0:01

Use CRegKey to delete the entries in the registry.

P-Rex

Asynch Serial Comms - IO Completion

louis15-Sep-04 22:40

louis

15-Sep-04 22:40

Hi there,

How can one allow the program to effectively wait until all the data has been received.
I have used the HasOverlappedIOCompleted and GetOverlappedResult function so far. But data is still incomplete. Only when I use Sleep(50) then I get all the data at once.
Code used to far :
while (!HasOverlappedIOCompleted (&ovRead));
and,
GetOverlappedResult(m_hComm, &ovRead, &BytesRead, TRUE);

Are there any other ways to wait?
I am reading 50 bytes at 9600 baud.

Thanks

Visual C++ (MFC) : Using Matrix to set an part of an image to zero

pohcb_sonic15-Sep-04 21:50

pohcb_sonic

15-Sep-04 21:50

pohcb_sonic 2:17 16 Sep '04

Hi! I'm new to MFC in Visual C++ programming. I had previously used it to do console applications but never used MFC before. I had a problem; I was told to set a 4 by 4 area by using Matrix in MFC coding and use it to check whether the image has any little "black spots". If it does, I have to set these small little "black spots" of the image from "255" or anything else to zero. The codings must be in a function.

So How do I do it?

Pls do kindly reply. I needed this asap. Thanks! Smile | :)

Below are the codes: Poke tongue | ;-P

<br />
void CMediVisionView::MatrixImage()<br />
{<br />
int i;<br />
<br />
if(no_of_rows==512){<br />
for(i=0; i<512-5; i++)<br />
{<br />
if (image512[i]==0 && image512[i+1]==0 && image512[i+2]==0 && image512[i+3]==0 && image512[i+4]==0){<br />
<br />
if(image512[i]==0 && image512[i+512]==0 && image512[i+(512*2)]==0 && image512[i+(512*3)]==0){<br />
<br />
if(image512[i+4]==0 && image512[i+512+4]==0 && image512[i+(512*2)+4]==0 && image512[i+(512*3)+4]==0){<br />
<br />
if(image512[i+(512*3)+1]==0 && image512[i+(512*3)+2]==0 && image512[i+(512*3)+3]==0 && image512[i+(512*3)+4]==0){<br />
<br />
image512[i+512+1]=0;<br />
image512[i+(512*2)+1]=0;<br />
image512[i+(512*3)+1]=0;<br />
<br />
image512[i+512+2]=0;<br />
image512[i+(512*2)+2]=0;<br />
image512[i+(512*3)+2]=0;<br />
<br />
image512[i+512+3]=0;<br />
image512[i+(512*2)+3]=0;<br />
image512[i+(512*3)+3]=0;<br />
			}<br />
				<br />
											       }<br />
										               }<br />
<br />
                       }<br />
		<br />
    }<br />
}<br />
<br />
<br />
<br />
}<br />
<br />

Re: Visual C++ (MFC) : Using Matrix to set an part of an image to zero

V.15-Sep-04 22:15

15-Sep-04 22:15

from MSDN:

SetPixelV
The SetPixelV function sets the pixel at the specified coordinates to the closest approximation of the specified color. The point must be in the clipping region and the visible part of the device surface.

BOOL SetPixelV(<br />
  HDC hdc,           // handle to device context<br />
  int X,             // x-coordinate of pixel<br />
  int Y,             // y-coordinate of pixel<br />
  COLORREF crColor   // new pixel color<br />
);

Parameters:
hdc
[in] Handle to the device context.
X
[in] Specifies the x-coordinate, in logical units, of the point to be set.
Y
[in] Specifies the y-coordinate, in logical units, of the point to be set.
crColor
[in] Specifies the color to be used to paint the point. To create a COLORREF color value, use the RGB macro.
Return Values
If the function succeeds, the return value is nonzero.

If the function fails, the return value is zero.

Windows NT/2000/XP: To get extended error information, call GetLastError.

Remarks
Not all devices support the SetPixelV function. For more information, see the description of the RC_BITBLT capability in the GetDeviceCaps function.

SetPixelV is faster than SetPixel because it does not need to return the color value of the point actually painted.

Requirements
Windows NT/2000/XP: Included in Windows NT 3.1 and later.
Windows 95/98/Me: Included in Windows 95 and later.
Header: Declared in Wingdi.h; include Windows.h.
Library: Use Gdi32.lib.

See Also
Bitmaps Overview, Bitmap Functions, GetDeviceCaps, SetPixel, COLORREF, RGB

I'm not sure which format of image it is, but I'm sure you can use the CDC class or something.

"If I don't see you in this world, I'll see you in the next one... and don't be late." ~ Jimi Hendrix

Re: Visual C++ (MFC) : Using Matrix to set an part of an image to zero

pohcb_sonic16-Sep-04 15:21

pohcb_sonic

16-Sep-04 15:21

I actually had previously used it to do console applications but never used MFC before. I had a problem; I was told to set a 4 by 4 area by using Matrix in MFC coding and use it to check whether the image has any little "black spots". If it does, I have to set these small little "black spots" of the image from "255" or anything else to zero. The codings must be in a function.

So How do I do it?

Pls do kindly reply. I needed this asap. Thanks!

Below are the codes:

void CMediVisionView::MatrixImage()
{
int i;

if(no_of_rows==512){
for(i=0; i<512-5; i++)
{
if (image512[i]==0 && image512[i+1]==0 && image512[i+2]==0 && image512[i+3]==0 && image512[i+4]==0){

if(image512[i]==0 && image512[i+512]==0 && image512[i+(512*2)]==0 && image512[i+(512*3)]==0){

if(image512[i+4]==0 && image512[i+512+4]==0 && image512[i+(512*2)+4]==0 && image512[i+(512*3)+4]==0){

if(image512[i+(512*3)+1]==0 && image512[i+(512*3)+2]==0 && image512[i+(512*3)+3]==0 && image512[i+(512*3)+4]==0){

image512[i+512+1]=0;
image512[i+(512*2)+1]=0;
image512[i+(512*3)+1]=0;

image512[i+512+2]=0;
image512[i+(512*2)+2]=0;
image512[i+(512*3)+2]=0;

image512[i+512+3]=0;
image512[i+(512*2)+3]=0;
image512[i+(512*3)+3]=0;
}

}
}

}

}
}

}

Re: Visual C++ (MFC) : Using Matrix to set an part of an image to zero

V.16-Sep-04 20:39

16-Sep-04 20:39

I would like to help, but I don't have the time to look things up (I have my own work too you know Smile | :)

).

Check out MSDN for CBitmap, CDC classes and search (google, Codeproject or something) on tutorials for jpg, gif, ...

My experience is that handling images always is a bit harder, but you'll get there.

Good luck.

"If I don't see you in this world, I'll see you in the next one... and don't be late." ~ Jimi Hendrix

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.