GDI+ screenshot save to JPG

[Owyn]

hi, i have a code to screen and save screen as png with GDI+, how do i change it to save as jpg?

void gdiscreen()
{
	GdiplusStartupInput gdiplusStartupInput;
	ULONG_PTR gdiplusToken;
	GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, NULL);

	HDC scrdc, memdc;
	HBITMAP membit;
	// Получаем HDC рабочего стола
	// Параметр HWND для рабочего стола всегда равен нулю.
	scrdc = GetDC(0);
	// Определяем разрешение экрана
	int Height, Width;
	Height = GetSystemMetrics(SM_CYSCREEN);
	Width = GetSystemMetrics(SM_CXSCREEN);
	// Создаем новый DC, идентичный десктоповскому и битмап размером с экран.
	memdc = CreateCompatibleDC(scrdc);
	membit = CreateCompatibleBitmap(scrdc, Width, Height);
	SelectObject(memdc, membit);
	// Улыбаемся... Снято!
	BitBlt(memdc, 0, 0, Width, Height, scrdc, 0, 0, SRCCOPY);
	HBITMAP hBitmap;
	hBitmap =(HBITMAP) SelectObject(memdc, membit);
	 Gdiplus::Bitmap bitmap(hBitmap, NULL);
    bitmap.Save(L"c:\\screen.png", &png);

	DeleteObject(hBitmap);

}

[carl666]

This code is wrong (memory leaks, etc)
The proper code had been posted on Win32 group
(http://groups.google.com/group/comp....topics?lnk=srg)

[Owyn]

i searched thru that group with no results =\
can you help me with me code?

[CBasicNet]

Here is the modified code to save to jpeg with the leaks fixed.

#include <GdiPlus.h>

void gdiscreen()
{
	using namespace Gdiplus;
	GdiplusStartupInput gdiplusStartupInput;
	ULONG_PTR gdiplusToken;
	GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, NULL);

	{
		HDC scrdc, memdc;
		HBITMAP membit;
		scrdc = ::GetDC(0);
		int Height = GetSystemMetrics(SM_CYSCREEN);
		int Width = GetSystemMetrics(SM_CXSCREEN);
		memdc = CreateCompatibleDC(scrdc);
		membit = CreateCompatibleBitmap(scrdc, Width, Height);
		HBITMAP hOldBitmap =(HBITMAP) SelectObject(memdc, membit);
		BitBlt(memdc, 0, 0, Width, Height, scrdc, 0, 0, SRCCOPY);

		Gdiplus::Bitmap bitmap(membit, NULL);
		CLSID clsid;
		GetEncoderClsid(L"image/jpeg", &clsid);
		bitmap.Save(L"D:\\screen.jpeg", &clsid);

		SelectObject(memdc, hOldBitmap);

		DeleteObject(memdc);

		DeleteObject(membit);

		::ReleaseDC(0,scrdc);
	}

	GdiplusShutdown(gdiplusToken);
}

int GetEncoderClsid(const WCHAR* format, CLSID* pClsid)
{
	using namespace Gdiplus;
	UINT  num = 0;          // number of image encoders
	UINT  size = 0;         // size of the image encoder array in bytes

	ImageCodecInfo* pImageCodecInfo = NULL;

	GetImageEncodersSize(&num, &size);
	if(size == 0)
		return -1;  // Failure

	pImageCodecInfo = (ImageCodecInfo*)(malloc(size));
	if(pImageCodecInfo == NULL)
		return -1;  // Failure

	GetImageEncoders(num, size, pImageCodecInfo);

	for(UINT j = 0; j < num; ++j)
	{
		if( wcscmp(pImageCodecInfo[j].MimeType, format) == 0 )
		{
			*pClsid = pImageCodecInfo[j].Clsid;
			free(pImageCodecInfo);
			return j;  // Success
		}    
	}

	free(pImageCodecInfo);
	return 0;
}

To compile and link the code, you need to add the gdiplus.lib to Project Properties->Linker->Input->Additional Dependencies. Or you can put the below pragma in source code.

#pragma comment( lib, "gdiplus" )

[Owyn]

thank you very much =)

one more question, how do i format filename? i have little problems with it, i want it to be

SYSTEMTIME SysTime;
    GetLocalTime(&SysTime);
char *filename= "%02d:%02d:%02d h";
	sprintf(filename,"screen%02d:%02d:%02d h.jpeg",timestring,SysTime.wHour,SysTime.wMinute,SysTime.wSecond);

but can't figure out how to use it in

bitmap.Save(L"D:\\screen.jpeg", &clsid);

[CBasicNet]

SYSTEMTIME SysTime;
GetLocalTime(&SysTime);
wchar_t filename[200];
memset(filename,0,sizeof(filename));
wsprintf(filename,L"screen%02d:%02d:%02d h.jpeg",SysTime.wHour,SysTime.wMinute,SysTime.wSecond);

[Owyn]

doesn't work, says impossible to convert param 1 from 'wchar_t[200] to 'LPSTR' =\

[CBasicNet]

you are using sprintf or wsprintf? GDI+ is using wide characters strings, not ASCII character strings.

[Owyn]

i'm useing code you gave me above, so wsprintf

[CBasicNet]

Can you post the line which got this compilation error? The code is working fine on my side.

[Owyn]

wsprintf(filename,L"screen%02d:%02d:%02d h.jpeg",SysTime.wHour,SysTime.wMinute,SysTime.wSecond);

[CBasicNet]

Strange. What compiler are you using? Meanwhile you can try the below.

SYSTEMTIME SysTime;
GetLocalTime(&SysTime);
TCHAR filename[200];
memset(filename,0,sizeof(filename));
wsprintf(filename,L"screen%02d:%02d:%02d h.jpeg",SysTime.wHour,SysTime.wMinute,SysTime.wSecond);

[Owyn]

Strange. What compiler are you using? Meanwhile you can try the below.

SYSTEMTIME SysTime;
GetLocalTime(&SysTime);
TCHAR filename[200];
memset(filename,0,sizeof(filename));
wsprintf(filename,L"screen%02d:%02d:%02d h.jpeg",SysTime.wHour,SysTime.wMinute,SysTime.wSecond);

visual studio 2008

this code gives same result on wsprintf line =\

Error 149 error C2664: wsprintfA: impossible to convert parameter 2 from 'const wchar_t [28]' to 'LPCSTR'

[CBasicNet]

Use wsprintfW then.

SYSTEMTIME SysTime;
GetLocalTime(&SysTime);
TCHAR filename[200];
memset(filename,0,sizeof(filename));
wsprintfW(filename,L"screen%02d:%02d:%02d h.jpeg",SysTime.wHour,SysTime.wMinute,SysTime.wSecond);

[Owyn]

Use wsprintfW then.

SYSTEMTIME SysTime;
GetLocalTime(&SysTime);
TCHAR filename[200];
memset(filename,0,sizeof(filename));
wsprintfW(filename,L"screen%02d:%02d:%02d h.jpeg",SysTime.wHour,SysTime.wMinute,SysTime.wSecond);

...

Error 149 error C2664: wsprintfW: impossible to convert parameter 1 from 'TCHAR [200]' to 'LPWSTR'