Screen Capture

2012-05-17T10:27:45Z

GDI:

新頁面

'''Screen Capture'''（抓圖）

==抓圖方式==
===GDI===
*以[[MFC]]方式，抓圖到
:[http://www.codeproject.com/Articles/3603/Classes-to-read-and-write-BMP-JPEG-and-JPEG-2000 TonyJpegLib]的CDib m_dib;
:以方便存成不同格式的圖檔
:（仍有bug，如果抓圖的寬度不為4的倍數時發生）
*[http://www.player.idv.tw/file/tool/screenshot.rar screenshot.rar]（完整SourceCode）
<source lang="cpp">
void CCaptureDlg::CaptureBmp(void)
{
LPCTSTR lpszDrawDeviceName = "DISPLAY";
CDC dc;
int Width;
int Height;
RECT WndRect;

//全螢幕
dc.CreateDC(lpszDrawDeviceName, NULL, NULL, NULL);
Width = GetSystemMetrics(SM_CXSCREEN);
Height = GetSystemMetrics(SM_CYSCREEN);

if (::GetKeyState(VK_SCROLL) == NULL)
{
WndRect.top = 0;
WndRect.bottom = Height;
WndRect.left = 0;
WndRect.right = Width;
}
else
{
//視窗
CWnd* pWnd = GetForegroundWindow();
pWnd->GetWindowRect(&WndRect);

if (WndRect.right < 0)
WndRect.right = 0;
if (WndRect.left > Width)
WndRect.left = Width;
if (WndRect.top < 0)
WndRect.top = 0;
if (WndRect.bottom > Height)
WndRect.bottom = Height;

Width = (WndRect.right - WndRect.left);
if ((Width % 4) != 0)
Width = ((Width >> 2)+1) << 2;
if (Width > GetSystemMetrics(SM_CXSCREEN))
Width = GetSystemMetrics(SM_CXSCREEN);
Height = WndRect.bottom - WndRect.top;
}

CBitmap bm;

bm.CreateCompatibleBitmap(&dc,Width,Height);

CDC tdc;
tdc.CreateCompatibleDC(&dc);

CBitmap*pOld=tdc.SelectObject(&bm);
tdc.BitBlt(0 , 0, Width,Height, &dc, WndRect.left, WndRect.top, SRCCOPY);

tdc.SelectObject(pOld);

BITMAP btm;
bm.GetBitmap(&btm);
DWORD size = btm.bmWidthBytes*btm.bmHeight;
LPSTR lpData = (LPSTR)GlobalAllocPtr(GPTR,size);
/////////////////////////////////////////////
BITMAPINFOHEADER bih;
bih.biBitCount = btm.bmBitsPixel;
bih.biClrImportant = 0;
bih.biClrUsed = 0;
bih.biCompression = 0;
bih.biHeight = btm.bmHeight;
bih.biPlanes = 1;
bih.biSize = sizeof(BITMAPINFOHEADER);
bih.biSizeImage = size;
bih.biWidth = btm.bmWidth;
bih.biXPelsPerMeter = 3780;//0;
bih.biYPelsPerMeter = 3780;//0;
///////////////////////////////////
if (btm.bmBitsPixel > 16)
{
GetDIBits(dc, bm, 0, bih.biHeight, lpData, (BITMAPINFO*)&bih, DIB_RGB_COLORS);
}
else
{
//bih.biClrImportant = 256;
//bih.biClrUsed = 256;
bm.GetBitmapBits(size, lpData);

//iRet = GetDIBits(dc, bm, 0, (bih.biHeight-1), lpData, (BITMAPINFO*)&bih, DIB_PAL_COLORS);
}

//////////////////////////////

BITMAPFILEHEADER bfh;
bfh.bfReserved1 = bfh.bfReserved2 = 0;
bfh.bfType = ((WORD)('M'<< 8)|'B');
bfh.bfSize = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) +size;//54+size;
bfh.bfOffBits = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER);//54;

//轉值修正
int size2 = 0;
LPBYTE lpData2 = NULL;

//16色模式
if (btm.bmBitsPixel < 8)
{
GlobalFreePtr(lpData);
return;
}

//256色模式
if (btm.bmBitsPixel == 8)
{
bih.biBitCount = 24;
bih.biSizeImage = size *3;
lpData2 = new(BYTE[bih.biSizeImage]);
size2 = bih.biSizeImage;
bih.biCompression = BI_RGB;

BYTE R, G, B, Color;
LPBYTE chBuffer = (LPBYTE)lpData,
chRgbBuffer = lpData2;
int ColorIndex = 0,
RgbIndex = 0;

PALETTEENTRY chColorTable[256];
::GetSystemPaletteEntries(dc.m_hDC,
0,
256,
chColorTable);

for(int y=(btm.bmHeight-1); y>0; y--)
{
ColorIndex = btm.bmWidthBytes * y;
for (int x=0; x<btm.bmWidth; x++)
{
Color = chBuffer[ColorIndex];
B = chColorTable[Color].peBlue;
G = chColorTable[Color].peGreen;
R = chColorTable[Color].peRed;

chRgbBuffer[RgbIndex] = B;
chRgbBuffer[RgbIndex+1] = G;
chRgbBuffer[RgbIndex+2] = R;

ColorIndex ++;
RgbIndex += 3;
}
}
}

//16bit HiColor模式 (555與565)
if (btm.bmBitsPixel == 16)
{
bih.biBitCount = 24;
bih.biSizeImage = size /2 *3;
lpData2 = new(BYTE[bih.biSizeImage]);
size2 = bih.biSizeImage;
bih.biCompression = BI_RGB;

WORD hiColor, R, G, B;
LPBYTE chBuffer = (LPBYTE)lpData,
chRgbBuffer = lpData2;
int HiColorIndex = 0,
RgbIndex = 0;

BOOL bIsHiColor555 = TRUE;

LPDIRECTDRAW lpdd_temp = NULL;
LPDIRECTDRAW4 lpdd = NULL;
DDSURFACEDESC2 ddsd;
LPDIRECTDRAWSURFACE4 lpdds_primary = NULL;
DDPIXELFORMAT PixelFormat;

if (DirectDrawCreate(NULL, &lpdd_temp, NULL) == DD_OK)
{
if (lpdd_temp->QueryInterface(IID_IDirectDraw4, (LPVOID *)&lpdd) == DD_OK)
{
memset(&ddsd, 0, sizeof(DDSURFACEDESC2));
ddsd.dwSize = sizeof(DDSURFACEDESC2);

lpdd->GetDisplayMode(&ddsd);
{
PixelFormat = ddsd.ddpfPixelFormat;
if (PixelFormat.dwGBitMask == 0x07e0)//.dwRGBBitCount == 16)
{
bIsHiColor555 = FALSE;
}
}
lpdd->Release();
}
lpdd_temp->Release();
}

if (bIsHiColor555 == TRUE)
{
//555
for(int y=(btm.bmHeight-1); y>0; y--)
{
HiColorIndex = btm.bmWidthBytes * y;
for (int x=0; x<btm.bmWidth; x++)
{
hiColor = (WORD)chBuffer[HiColorIndex] + (WORD)(chBuffer[HiColorIndex+1]<<8);

R = (hiColor & 0x7C00) >> 7;
G = (hiColor & 0x03E0) >> 2;
B = (hiColor & 0x001F) << 3;

chRgbBuffer[RgbIndex] = (BYTE) B;
chRgbBuffer[RgbIndex+1] = (BYTE) G;
chRgbBuffer[RgbIndex+2] = (BYTE) R;

HiColorIndex += 2;
RgbIndex += 3;
}
}
}
else
{
//565
for(int y=(btm.bmHeight-1); y>0; y--)
{
HiColorIndex = btm.bmWidthBytes * y;
for (int x=0; x<btm.bmWidth; x++)
{
hiColor = (WORD)chBuffer[HiColorIndex] + (WORD)(chBuffer[HiColorIndex+1]<<8);

R = (hiColor & 0xF800) >> 8;
G = (hiColor & 0x07E0) >> 3;
B = (hiColor & 0x001F) << 3;

chRgbBuffer[RgbIndex] = (BYTE) B;
chRgbBuffer[RgbIndex+1] = (BYTE) G;
chRgbBuffer[RgbIndex+2] = (BYTE) R;

HiColorIndex += 2;
RgbIndex += 3;
}
}
}
}

// 24Bit True Color 模式
if (btm.bmBitsPixel == 24)
{
bih.biBitCount = 24;
bih.biSizeImage = size;
lpData2 = new(BYTE[bih.biSizeImage]);
::memcpy(lpData2, lpData, bih.biSizeImage);
size2 = bih.biSizeImage;
bih.biCompression = BI_RGB;
}

// 32Bit True Color 模式
if (btm.bmBitsPixel == 32)
{
bih.biBitCount = 24;
bih.biSizeImage = size /4 *3;
lpData2 = new(BYTE[bih.biSizeImage]);
size2 = bih.biSizeImage;
bih.biCompression = BI_RGB;

BYTE R, G, B;
LPBYTE chBuffer = (LPBYTE)lpData,
chRgbBuffer = lpData2;
int ColorIndex = 0,
RgbIndex = 0;

for(int y=0; y<btm.bmHeight; y++)
{
ColorIndex = btm.bmWidthBytes * y;
for (int x=0; x<btm.bmWidth; x++)
{
B = chBuffer[ColorIndex];
G = chBuffer[ColorIndex+1];
R = chBuffer[ColorIndex+2];

chRgbBuffer[RgbIndex] = B;
chRgbBuffer[RgbIndex+1] = G;
chRgbBuffer[RgbIndex+2] = R;

ColorIndex += 4;
RgbIndex += 3;
}
}
}

m_dib.SetDIBits(&bfh, &bih, lpData2);

delete [] lpData2;

GlobalFreePtr(lpData);
}
</source>

===GDI+===
*參照：[http://www.dotblogs.com.tw/chou/archive/2009/03/08/7410.aspx C#做出 Print Screen 儲存螢幕畫面的功能 -【.NET菜鳥自救會】]
<source lang="csharp">
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace ImageToolkit
{
public class ScreenCapture
{
//全螢幕
public static Bitmap CaptureFullScreen()
{
Bitmap img = new Bitmap(Screen.PrimaryScreen.Bounds.Width, Screen.PrimaryScreen.Bounds.Height, PixelFormat.Format24bppRgb);
using (Graphics g = Graphics.FromImage(img))
{
g.CopyFromScreen(new Point(0,0),
new Point(0, 0),
new Size(Screen.PrimaryScreen.Bounds.Width, Screen.PrimaryScreen.Bounds.Height));
}
return img;
}

//視窗(Windows Form)
public static Bitmap CaptureFullForm(Form form1)
{
Bitmap img = new Bitmap(form1.Width, form1.Height, PixelFormat.Format24bppRgb);
using (Graphics g = Graphics.FromImage(img))
{
g.CopyFromScreen(new Point(form1.Location.X, form1.Location.Y),
new Point(0, 0),
new Size(form1.Width, form1.Height));
}
return img;
}

}
}
</source>

[[Category:技術]]
[[Category:GDI+]]

Windows Image Acquisition

2012-05-15T09:36:46Z

FAQ:

顯示差異

DirectShow

2012-05-15T08:53:57Z

←上一修訂		在2012年5月15日 (二) 08:53所做的修訂版本
（1個中途的修訂版本沒有顯示）
第8行：		第8行：
	*[http://msdn.microsoft.com/en-us/windows/bb980924.aspx Windows SDK]		*[http://msdn.microsoft.com/en-us/windows/bb980924.aspx Windows SDK]
	:DirectShow SDK原本放在DirectX SDK裡，但自DirectX 9.0c SDK以後，被移到Windows SDK。		:DirectShow SDK原本放在DirectX SDK裡，但自DirectX 9.0c SDK以後，被移到Windows SDK。
		+	*[http://sourceforge.net/projects/directshownet/ DirectShow.NET]

	==技術文件==		==技術文件==
第14行：		第15行：
	* [http://www.free-codecs.com/download/RadLight_MPC_DirectShow_Filter.htm Radlight Ogg Theora DirectShow filter]		* [http://www.free-codecs.com/download/RadLight_MPC_DirectShow_Filter.htm Radlight Ogg Theora DirectShow filter]
	* [http://wiki.jrmediacenter.com/index.php/DirectShow_Playback_Guide J. River DirectShow Playback Guide] – ''A tutorial on DirectShow focused on J. River's Media Center, but contains good general-purpose information as well.''		* [http://wiki.jrmediacenter.com/index.php/DirectShow_Playback_Guide J. River DirectShow Playback Guide] – ''A tutorial on DirectShow focused on J. River's Media Center, but contains good general-purpose information as well.''
		+
		+	==應用==
		+	===DirectShow.NET===
		+	*[http://tw.myblog.yahoo.com/sl7333/article?mid=2367&prev=2422&next=2305&l=f&fid=26 WebCam 擷取畫面 (使用 DirectShow .Net)]
		+	*[http://www.barebonescoder.com/2012/01/finding-your-web-cam-with-c-directshow-net/ Finding Your Web Cam with C# & DirectShow.NET]
		+	*[http://www.codeproject.com/Articles/18511/Webcam-using-DirectShow-NET Webcam using DirectShow.NET]

	==相關==		==相關==

ProgWiki - 近期變動 [zh-tw]

Screen Capture

Windows Image Acquisition

DirectShow