Chicken of the VNC and Ubuntu 14.04 LTS

Upgrading an Ubuntu system to Ubuntu 14.04LTS seems to stop Chicken of the VNC working for remote desktop access, even after the Ubuntu system has been configured in the normal way to allow remote desktop access. To fix this, install dconf-tools:

sudo apt-get install dconf-tools

Then, run dconf-editor and change the org/gnome/desktop/remote-access/require-encryption to off so that it looks something like this:

dconfThat seems to fix it, although at the expense of requiring encryption.

The brain and parallel processing

Interesting story here about what parallel resources the brain musters to perform simple tasks. It suggests that trying to build a functional brain-analog by simulating individual neurons is unnecessary. Instead, a much more practical silicon implementation would come from understanding the aggregate behavior of groups of neurons and simulating that instead. Not a new idea but it’s interesting to see an attempt to start to understand how this might work.

Continue reading “The brain and parallel processing”

A global quantum internet?

Interesting paper here describing a potential system for creating caches of quantum entangled photon pairs separated by very large distances. It wasn’t all that long ago that the concept of entanglement seemed like science fiction and, in any case, entanglement was so fragile that things de-cohered in a very short space of time. Now it seems like it may be possible to store widely separated entangled pairs for at least long enough (> 67mS) to be useful for things like quantum key distribution.

Decision Forests

forestDecision Forests (also called random trees, random forests etc) are a machine learning system that can be applied to many tasks including image recognition. What’s nice is that software is available here, OpenCV has an implementation and there’s also a GPU implementation along with no doubt many others. The image shows one of the examples using the Microsoft code where the forest has learned the classification of a spiral pattern. This paper describes a very interesting project using multiple layers of decision forests to determine depth using reflected near IR illumination intensity so that an (almost) standard webcam can recover depth information for things like gesture recognition. The nice thing is that the sensor can be very small and processing overhead is very low.

GStreamer launch for processing RTSP/H.264 video on the Jetson TK1

IP cameras such as the Foscam FI9821 stream network video using H.264 over RTSP. The gstreamer-0.10 launch code snippet below creates a pipeline that allows an application to get access to the streaming video as a series of RGB frames via the appsink plug-in. It makes use of the Jetson TK1‘s hardware acceleration for H.264 decoding.

launch = g_strdup_printf (
     " rtspsrc location=rtsp://%s:%d/videoMain user-id=%s user-pw=%s "
     " ! gstrtpjitterbuffer ! rtph264depay ! queue ! nv_omx_h264dec "
     " ! capsfilter caps=\"video/x-raw-yuv\" ! ffmpegcolorspace "
     " ! capsfilter caps=\"video/x-raw-rgb\" ! queue ! appsink name=videoSink0 "
     m_IPAddress, m_port, m_user, m_pw);
 m_pipeline = gst_parse_launch(launch, &error);