Remote Control article: Crawl Remote screen image

Remote Control article: Crawl Remote screen image

{Capture screen image, save as memory stream--bmp stream, compress bmp stream, JPG stream, and use stream}
{The speed of transmitting BMP and JPG streams in the network has not been tested}
{Compression of BMP stream is lossless compression}
{
Global variables
Memorystream:tmemorystream;
Memorystream:=tmemorystream.create;
}

Var
Image:timage;
Jpgstream:tjpegimage;
Ss:tcanvas;

Begin
Ss:=tcanvas. Create;
Ss. HANDLE:=GETDC (0);
Image:=timage. Create (self);
Image.width:=screen.width;
Image. Height:=screen. Height;
Image.picture.bitmap.pixelformat:= Pf16bit;
BitBlt (image.canvas.handle,0,0,image.width,image.height,ss.handle,0,0,srccopy);

{Large raw BMP stream
Image.picture.bitmap.SaveToStream (MemoryStream);
}

{Lossless compression BMP stream uses Zlib.pas
{First define variable Count,deststream,sourcestream}
Image.picture.bitmap.SaveToStream (MemoryStream);
Count:=memorystream.size;
Deststream:=tmemorystream.create;
{compression mode: Clnone,clfastest,cldefault,clmax}
Sourcestream:=tcompressionstream.create (Cldefault, Deststream);
Try
Memorystream.savetostream (Sourcestream);
Sourcestream.free;
Memorystream.clear;
Memorystream.writebuffer (Count, SizeOf (count));
Memorystream.copyfrom (deststream, 0);
Finally
Deststream.free;
End
}

{JPG stream uses JPEG
Jpgstream:= tjpegimage.create;
Jpgstream. Assign (IMAGE.PICTURE.BITMAP);
jpgstream.compressionquality:=50; {Compression quality}
jpgstream.compress;
Jpgstream. Savetostream (MemoryStream); {Save as JPG stream}
Jpgstream.free;
}

ReleaseDC (0,SS. Handle);
Image.free;

{Send memory Stream ...}

-----------------------------------------------------
{Receive memory Stream ...}

{Using BMP Streams
Image. Picture.Bitmap.LoadFromStream (Bmpstream);}

{Restore compressed BMP stream Uses:Zlib.pas
First define the variable Count,buffer,deststream,sourcestream
MemoryStream is a compressed BMP stream
Memorystream.readbuffer (Count, SizeOf (count));
Getmem (Buffer, Count);
Deststream:=tmemorystream.create;
Sourcestream:=tdecompressionstream.create (MemoryStream);
Try
Sourcestream.readbuffer (buffer^, Count);
Deststream.writebuffer (buffer^, Count);
deststream.position:=0;
Image. Picture.Bitmap.LoadFromStream (Deststream);
Finally
Freemem (Buffer);
Deststream.free;
End
}

Use the JPG stream image. Picture.assign (Jpgstream);

Remote Control article: Crawl Remote screen image