image - Saving Surface to Bitmap and optimizing DirectX screen capture in C# -

after whole day of testing came code, captures current screen using directx (slimdx) , saves file:

device d;  public dxscreencapture() {     presentparameters present_params = new presentparameters();     present_params.windowed = true;     present_params.swapeffect = swapeffect.discard;     d = new device(new direct3d(), 0, devicetype.hardware, intptr.zero, createflags.softwarevertexprocessing, present_params); }  public surface capturescreen() {     surface s = surface.createoffscreenplain(d, screen.primaryscreen.bounds.width, screen.primaryscreen.bounds.height, format.a8r8g8b8, pool.scratch);     d.getfrontbufferdata(0, s);     return s; } 

then following:

   dxscreencapture sc = new dxscreencapture(); 

..code here

    private void button1_click(object sender, eventargs e)     {          stopwatch stopwatch = new stopwatch();          // begin timing         stopwatch.start();          surface s = sc.capturescreen();         surface.tofile(s, @"c:\temp\test.png", imagefileformat.png);          s.dispose();          stopwatch.stop();          textbox1.text = ("elapsed:" + stopwatch.elapsed.totalmilliseconds);     } 

the results are:

0. when don't save surface: avg. elapsed time: 80-90ms

1. when save surface bmp file: format: imagefileformat.bmp , avg. elapsed time: 120ms, file size: 7mb

2. when save surface png file: format: imagefileformat.png , avg. elapsed time: 800ms, file size: 300kb

the questions are:

1. possible optimise current image capture? according article - directx screen capture should faster gdi. me, gdi takes 20ms "bitmap", whereas takes 80ms "surfare" using dx (both without saving).

http://www.codeproject.com/articles/274461/very-fast-screen-capture-using-directx-in-csharp

2a. how save surface png image format faster? when save surface 7mb bmp file takes 6 times less time, when save same surface 300kb png file..

2b. possible save surface directly bitmap don't have create temporary files?

so don't have following: surface -> image file; image file open -> bitmap;, instead: surface -> bitmap

that's now. i'll gladly accept tips, thanks!

edit:

just solved 2b doing:

bitmap bitmap = new bitmap(slimdx.direct3d9.surface.tostream(s, slimdx.direct3d9.imagefileformat.bmp)); 

edit2:

surface.tofile(s, @"c:\temp\test.bmp", imagefileformat.bmp); bitmap bitmap = new bitmap(@"c:\temp\test.bmp"); 

is faster than:

bitmap bitmap = new bitmap(slimdx.direct3d9.surface.tostream(s, slimdx.direct3d9.imagefileformat.bmp)); 

by 100 ms!!! yeah, couldn't believe eyes ;) don't idea of temporary file creation, 50% performance increase (100-200ms instead of 200-300+) thing.

if don't want use slimdx library can try

public bitmap gimmebitmap(surface s) {     graphicsstream gs = surfaceloader.savetostream(imagefileformat.bmp, s);     return new bitmap(gs); } 

and try same .png - did not tested performance it have to faster using disc temporary file :)

and 1st question - try once create surface , on every screenshot put device's buffer data , create bitmap

d.getfrontbufferdata(0, s); return new bitmap(surfaceloader.savetostream(imagefileformat.bmp, s)); 

this should save time :)