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@IISResetMe
Created July 4, 2018 00:50
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Save IISResetMe/09ee81bf96b4f448bab505b1ef07f703 to your computer and use it in GitHub Desktop.
Gif capturer in PowerShell
# PowerShell gif encoding + wrapper around https://www.developerfusion.com/code/4630/capture-a-screen-shot/
Add-Type -TypeDefinition @'
using System;
using System.Runtime.InteropServices;
using System.Drawing;
using System.Drawing.Imaging;
namespace GDI
{
/// <summary>
/// Provides functions to capture the entire screen, or a particular window, and save it to a file.
/// </summary>
public class ScreenCapture
{
/// <summary>
/// Creates an Image object containing a screen shot of the entire desktop
/// </summary>
/// <returns></returns>
public Image CaptureScreen()
{
return CaptureWindow( User32.GetDesktopWindow() );
}
/// <summary>
/// Creates an Image object containing a screen shot of a specific window
/// </summary>
/// <param name="handle">The handle to the window. (In windows forms, this is obtained by the Handle property)</param>
/// <returns></returns>
public Image CaptureWindow(IntPtr handle)
{
// get te hDC of the target window
IntPtr hdcSrc = User32.GetWindowDC(handle);
// get the size
User32.RECT windowRect = new User32.RECT();
User32.GetWindowRect(handle,ref windowRect);
int width = windowRect.right - windowRect.left;
int height = windowRect.bottom - windowRect.top;
// create a device context we can copy to
IntPtr hdcDest = GDI32.CreateCompatibleDC(hdcSrc);
// create a bitmap we can copy it to,
// using GetDeviceCaps to get the width/height
IntPtr hBitmap = GDI32.CreateCompatibleBitmap(hdcSrc,width,height);
// select the bitmap object
IntPtr hOld = GDI32.SelectObject(hdcDest,hBitmap);
// bitblt over
GDI32.BitBlt(hdcDest,0,0,width,height,hdcSrc,0,0,GDI32.SRCCOPY);
// restore selection
GDI32.SelectObject(hdcDest,hOld);
// clean up
GDI32.DeleteDC(hdcDest);
User32.ReleaseDC(handle,hdcSrc);
// get a .NET image object for it
Image img = Image.FromHbitmap(hBitmap);
// free up the Bitmap object
GDI32.DeleteObject(hBitmap);
return img;
}
/// <summary>
/// Captures a screen shot of a specific window, and saves it to a file
/// </summary>
/// <param name="handle"></param>
/// <param name="filename"></param>
/// <param name="format"></param>
public void CaptureWindowToFile(IntPtr handle, string filename, ImageFormat format)
{
Image img = CaptureWindow(handle);
img.Save(filename,format);
}
/// <summary>
/// Captures a screen shot of the entire desktop, and saves it to a file
/// </summary>
/// <param name="filename"></param>
/// <param name="format"></param>
public void CaptureScreenToFile(string filename, ImageFormat format)
{
Image img = CaptureScreen();
img.Save(filename,format);
}
/// <summary>
/// Helper class containing Gdi32 API functions
/// </summary>
private class GDI32
{
public const int SRCCOPY = 0x00CC0020; // BitBlt dwRop parameter
[DllImport("gdi32.dll")]
public static extern bool BitBlt(IntPtr hObject,int nXDest,int nYDest,
int nWidth,int nHeight,IntPtr hObjectSource,
int nXSrc,int nYSrc,int dwRop);
[DllImport("gdi32.dll")]
public static extern IntPtr CreateCompatibleBitmap(IntPtr hDC,int nWidth,
int nHeight);
[DllImport("gdi32.dll")]
public static extern IntPtr CreateCompatibleDC(IntPtr hDC);
[DllImport("gdi32.dll")]
public static extern bool DeleteDC(IntPtr hDC);
[DllImport("gdi32.dll")]
public static extern bool DeleteObject(IntPtr hObject);
[DllImport("gdi32.dll")]
public static extern IntPtr SelectObject(IntPtr hDC,IntPtr hObject);
}
/// <summary>
/// Helper class containing User32 API functions
/// </summary>
private class User32
{
[StructLayout(LayoutKind.Sequential)]
public struct RECT
{
public int left;
public int top;
public int right;
public int bottom;
}
[DllImport("user32.dll")]
public static extern IntPtr GetDesktopWindow();
[DllImport("user32.dll")]
public static extern IntPtr GetWindowDC(IntPtr hWnd);
[DllImport("user32.dll")]
public static extern IntPtr ReleaseDC(IntPtr hWnd,IntPtr hDC);
[DllImport("user32.dll")]
public static extern IntPtr GetWindowRect(IntPtr hWnd,ref RECT rect);
}
}
}
'@ -Language CSharp -ReferencedAssemblies system.drawing
function Capture-Screen {
param(
[GDI.ScreenCapture]$SC
)
$Filename = Join-Path $PWD "capt$(date -Format yyMMddhhmmssffff).bmp"
$SC.CaptureWindowToFile((Get-Process -Id $PID).MainWindowHandle,$Filename,'Bmp')
}
# Generate some random output, take screenshots
0..10|%{
Get-Random
Capture-Screen -SC $sc
Start-Sleep -Milliseconds 200
}
$enc = [System.Windows.Media.Imaging.GifBitmapEncoder]::new()
foreach($frame in Get-ChildItem .\capt*.bmp){
$bmp = [System.Drawing.Bitmap]::FromFile($frame.FullName)
$hbmp = $bmp.GetHbitMap()
$bmpsrc = [System.Windows.Interop.Imaging]::CreateBitmapSourceFromHBitmap($hbmp, [System.IntPtr]::Zero, 'Empty', [System.Windows.Media.Imaging.BitmapSizeOptions]::FromEmptyOptions())
$enc.Frames.Add([System.Windows.Media.Imaging.BitmapFrame]::Create($bmpsrc))
$hbmp = $bmp = $null
}
$filestream = [System.IO.File]::Create((Join-Path $PWD output.gif))
$enc.Save($filestream)
Remove-Item .\capt*.bmp
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