Video compression

One of the discussions within the Spice team is how to encode video for the remote desktop. So I spent a little bit of time doing some research on that front.

VM installation

Installed several VMs on Muse and began setting them up:

  • Ubuntu 14.04 LTS
  • Ubuntu 16.04 LTS
  • Ubuntu 16.10

The out of the box experience running these on Fedora 25 is quite inferior. Ubuntu 16.10 is not recognized by virt-manager, so the OS is marked as Unkown/unknown. Also, remote control over VNC of virt-manager is quite bad.

Apparently, the QXL drivers are not enabled by default in Ubuntu. As a result, you only get relative cursor within the guest, and no detection that you are trying to leave the guest desktop area (i.e. smooth transition of the mouse cursor between the “in guest” area and the host desktop). Keyboard is also behaving quite strangely. And the refresh rate I get over VNC in this configuration is extremely slow.

The result is that I need to go in front of the machine and do everything locally. Which means moving the cat sitting in the chair there, which is always a dangerous proposition. All in all, the experience with Ubuntu guests is really affected. I’m tempted to do another install with VMware driver emulation, because I believe this is enabled by default.

Video compression

Tried to explore video compression a bit deeper, to see what parameters could possibly affect video quality.

A good book about video compression, thank you Julien Maillard. Also this post gives ideas about how to do some desktop streaming testing. Since I was working

GMail aliases

I was still sending e-mails with the wrong alias. It turns out this is the solution. If you don’t do this, Google mail servers will automatically rewrite your SMTP From: lines to, the primary e-mail for that account, and then add an X-Google-Originally-From line, which no mailing list server seems to check.

Mac Spice

Began investigating the error in Mac Spice. The error symptoms with autom4ke are apparently relatively frequent but there is no clear pattern, besides this being an issue that seems to have appeared with autogen 2.69. I have the same 2.69 version on Muse (Linux box) and on Ptitpuce (Mac). So I wonder what is different.

I tried to wade through Perl code, which gets really annoying very quickly.


Author: Christophe de Dinechin

I try to change the world, but that's work in progress. If you want to know me, google "Christophe de Dinechin". Keywords: concept programming, virtualization, OS design, programming languages, video games, 3D, modern physics. Some stuff I did that I'm proud of: the first "true" 3D game for the PC, HP's big iron virtualization, real-time test systems for car electronics, some of the best games for the HP48 calculator, a theory of physics that makes sense (at least to me).

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