michael@0: /*
michael@0:  * Copyright (c) 2009, The Mozilla Foundation
michael@0:  * All rights reserved.
michael@0:  *
michael@0:  * Redistribution and use in source and binary forms, with or without
michael@0:  * modification, are permitted provided that the following conditions are met:
michael@0:  *     * Redistributions of source code must retain the above copyright
michael@0:  *       notice, this list of conditions and the following disclaimer.
michael@0:  *     * Redistributions in binary form must reproduce the above copyright
michael@0:  *       notice, this list of conditions and the following disclaimer in the
michael@0:  *       documentation and/or other materials provided with the distribution.
michael@0:  *     * Neither the name of the Mozilla Foundation nor the
michael@0:  *       names of its contributors may be used to endorse or promote products
michael@0:  *       derived from this software without specific prior written permission.
michael@0:  *
michael@0:  * THIS SOFTWARE IS PROVIDED BY The Mozilla Foundation ''AS IS'' AND ANY
michael@0:  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
michael@0:  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
michael@0:  * DISCLAIMED. IN NO EVENT SHALL The Mozilla Foundation BE LIABLE FOR ANY
michael@0:  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
michael@0:  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
michael@0:  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
michael@0:  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
michael@0:  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
michael@0:  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
michael@0:  *
michael@0:  * Contributors:
michael@0:  *   Ted Mielczarek <ted.mielczarek@gmail.com>
michael@0:  */
michael@0: /*
michael@0:  * screenshot.cpp : Save a screenshot of the Windows desktop in .png format.
michael@0:  *  If a filename is specified as the first argument on the commandline,
michael@0:  *  then the image will be saved to that filename. Otherwise, the image will
michael@0:  *  be saved as "screenshot.png" in the current working directory.
michael@0:  */
michael@0: 
michael@0: #undef WIN32_LEAN_AND_MEAN
michael@0: #include <windows.h>
michael@0: #include <gdiplus.h>
michael@0: 
michael@0: using namespace Gdiplus;
michael@0: 
michael@0: // From http://msdn.microsoft.com/en-us/library/ms533843%28VS.85%29.aspx
michael@0: static int GetEncoderClsid(const WCHAR* format, CLSID* pClsid)
michael@0: {
michael@0:   UINT  num = 0;          // number of image encoders
michael@0:   UINT  size = 0;         // size of the image encoder array in bytes
michael@0: 
michael@0:   ImageCodecInfo* pImageCodecInfo = nullptr;
michael@0: 
michael@0:   GetImageEncodersSize(&num, &size);
michael@0:   if(size == 0)
michael@0:     return -1;  // Failure
michael@0: 
michael@0:   pImageCodecInfo = (ImageCodecInfo*)(malloc(size));
michael@0:   if(pImageCodecInfo == nullptr)
michael@0:     return -1;  // Failure
michael@0: 
michael@0:   GetImageEncoders(num, size, pImageCodecInfo);
michael@0: 
michael@0:   for(UINT j = 0; j < num; ++j)
michael@0:     {
michael@0:       if( wcscmp(pImageCodecInfo[j].MimeType, format) == 0 )
michael@0:         {
michael@0:           *pClsid = pImageCodecInfo[j].Clsid;
michael@0:           free(pImageCodecInfo);
michael@0:           return j;  // Success
michael@0:         }    
michael@0:     }
michael@0: 
michael@0:   free(pImageCodecInfo);
michael@0:   return -1;  // Failure
michael@0: }
michael@0: 
michael@0: #ifdef __MINGW32__
michael@0: extern "C"
michael@0: #endif
michael@0: int wmain(int argc, wchar_t** argv)
michael@0: {
michael@0:   GdiplusStartupInput gdiplusStartupInput;
michael@0:   ULONG_PTR gdiplusToken;
michael@0:   GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, nullptr);
michael@0: 
michael@0:   HWND desktop = GetDesktopWindow();
michael@0:   HDC desktopdc = GetDC(desktop);
michael@0:   HDC mydc = CreateCompatibleDC(desktopdc);
michael@0:   int width = GetSystemMetrics(SM_CXSCREEN);
michael@0:   int height = GetSystemMetrics(SM_CYSCREEN);
michael@0:   HBITMAP mybmp = CreateCompatibleBitmap(desktopdc, width, height);
michael@0:   HBITMAP oldbmp = (HBITMAP)SelectObject(mydc, mybmp);
michael@0:   BitBlt(mydc,0,0,width,height,desktopdc,0,0, SRCCOPY|CAPTUREBLT);
michael@0:   SelectObject(mydc, oldbmp);
michael@0: 
michael@0:   const wchar_t* filename = (argc > 1) ? argv[1] : L"screenshot.png";
michael@0:   Bitmap* b = Bitmap::FromHBITMAP(mybmp, nullptr);
michael@0:   CLSID  encoderClsid;
michael@0:   Status stat = GenericError;
michael@0:   if (b && GetEncoderClsid(L"image/png", &encoderClsid) != -1) {
michael@0:     stat = b->Save(filename, &encoderClsid, nullptr);
michael@0:   }
michael@0:   if (b)
michael@0:     delete b;
michael@0:   
michael@0:   // cleanup
michael@0:   GdiplusShutdown(gdiplusToken);
michael@0:   ReleaseDC(desktop, desktopdc);
michael@0:   DeleteObject(mybmp);
michael@0:   DeleteDC(mydc);
michael@0:   return stat == Ok ? 0 : 1;
michael@0: }