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This bug tracker and wiki are being discontinued
please use https://github.com/Xpra-org/xpra instead.

We have moved

This page has been moved to https://github.com/Xpra-org/xpra/blob/master/docs/Features/Image-Depth.md

Archived copy:

Image Depth


Starting with version 2.0, you can simply specify which pixel bit depth you want to use when starting a session:

xpra start --pixel-depth=30

Support for each subcommand:

  • "xpra start" supports bit depths 16,24 and 30
  • "xpra start-desktop" supports 8,16,24 and 30
  • "xpra attach" supports 16,24,30,48 (with xpra version 2.1 or later only)

Testing that high bit depth is in use can be tricky, for that we provide a test application: #1553.


  • the operating system and display must be configured for deep colour support
  • transparency is supported in 24-bit mode, which is in effect a 32-bit mode
  • with versions older than 4.1, 30-bit rendering is only supported in the opengl enabled client, and only the rgb encoding will preserve high bit depth
  • 16-bit mode has no real native encoders and so the pixels are often upsampled to 24-bit before compression which is wasteful
  • 8-bit mode is not optimized
  • see wiki/Colourspace


Codec support for 10 bit per channel (aka 30 bit):

Last modified 17 months ago Last modified on 02/06/21 13:54:09