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Is it too much to ask to have ONE good image display API in Windows?

Lately, I've been becoming increasingly frustrated with how difficult it is in Windows to reliably and efficiently blit an image to the screen with high quality. It shouldn't be that hard, but it is, because there are half a dozen different ways to do so and none of them meet all of the requirements. So I sat down and made a table of all of the ways to blit an image to the screen in Windows, and how they all suck in some fashion.

VirtualDub has code paths for GDI, DirectDraw blit, DirectDraw overlay, Direct3D, and OpenGL. GDI+ is here because it looks like a good API, until you discover that it has no useful hardware acceleration, has incorrect subpixel positioning for image blits, and is no longer being evolved. I put WPF (Avalon) here because I looked into it as a possible alternative when operating under DWM composition / Aero Glass on Vista, which is problematic since neither GDI nor DirectDraw are accelerated, and Direct3D in child windows seems very flaky. The huge problem with WPF is that it requires .NET managed code, since the API is in .NET and the underlying MIL API isn't documented (grumble); another problem is that it seems unusually slow and flickers a lot whenever windows are resized.

Anyway, the table of image blitting woe:

GDI GDI+ DirectDraw
Direct3D OpenGL WPF (Avalon)
Platform support 95+
driver XP+[12]
Requires managed code no no no no no no yes
Hardware accel w/o 3D HW yes no yes yes no no no
Hardware accel with 3D HW yes no yes yes yes yes yes
Software fallback yes yes yes no yes [3] yes [4] yes [3]
Works with DWM composition sw sw sw no [5] yes yes yes
Bilinear filtering sw [13] sw yes [6] yes [7] yes yes yes
Bicubic filtering no sw no no yes [8] yes [8] sw
Terminal Services sw sw sw no no no sw [9]
Supports 256 color display yes yes yes yes no no ?
RGB format conversion yes sw no no [10] yes yes yes
YCbCr format conversion no no no yes yes yes no
Beam detection no no yes yes yes no no
Beam avoidance (vsync) no [11] no [11] yes yes yes yes no [11]



  1. Requires redistributable prior to Windows XP.
  2. Requires redistributable for Windows 95.
  3. With RGBRast. (Refrast is not counted as it requires the SDK and is excruciatingly slow.)
  4. Microsoft's OpenGL 1.1 software implementation is available, but it is very slow.
  5. Not supported. Overlay creation succeeds, but the overlay never shows up.
  6. DirectDraw blits are point-sampled when DWM composition (Aero Glass) is active. Otherwise, filtering is up to the driver.
  7. Varies widely; some drivers don't interpolate vertically, and some only interpolate chroma.
  8. Requires custom implementation.
  9. Can be hardware accelerated between two Vista-based systems using Avalon Remoting.
  10. RGB overlays are possible, but I've never seen hardware that supported it.
  11. Automatic if DWM composition (Aero Glass) is enabled.
  12. Requires redistributable.
  13. Requires Windows NT; quite slow.


This blog was originally open for comments when this entry was first posted, but was later closed and then removed due to spam and after a migration away from the original blog software. Unfortunately, it would have been a lot of work to reformat the comments to republish them. The author thanks everyone who posted comments and added to the discussion.