ucostyio

Programming without purpose, Image dithering and a CDP Transponder

Inspired by a forum post on osdev.org about image colour down-sampling I decided to have a crack at writing a program which could take a 24-bit image and convert it down to any lesser image format. The picture above shows an image split down the middle. On the right is the original 24-bit colour version and on the left is a 8-bit per pixel version with 2 bits for the red colour channel and 3 bits for the green and blue colour channels (rather than having a specific palette for the image I am down-sampling to a 2:3:3 BPP image). As you can see the colour loss is acceptable and despite the limitations it still looks nice. Obviously the image could be improved further by choosing a colour palette suitable for the image but that is for another project.

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Scraping the surface - Cisco 7970G Hardware

The Cisco 7970 is a black box piece of hardware and as such there is very little information about it on the internet. Cisco pretend it’s a closed appliance and as such go out of their way to prevent people for using the in a more flexible manner.

As of late I’ve been doing quite a bit of Cisco phone trickery. I’ve gotten a network of Cisco phones working with Asterisk and I’ve been building up sleek looking XML services for the 797x models. What I really want to do, though, is delve a little deeper into the spirit of hardware hacking and see if I can properly customise the phone beyond what is possible with configuration files.

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Work in progress, Cisco XML services

Recently I was inspired by a thread on the Whirlpool forums to write XML services for the Cisco IP phones I have. What I have created is something I have called (most creatively) Dashboard. It is a modular PHP script that allows people to add various blocks of dynamic content on to a page which is displayed on the IP phone’s display. This script can be called directly by the phone or pushed using the cisco XML push service.

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