Compact MythTV Frontend Advisor: Professor Wilsey Dustin Grimmeissen Richard Anderson David Kesler

MythTV Open source software intended to replace TIVO and other proprietary DVR systems Runs on a Linux machine storing video and other media to the hard drive Media can be played back from hard drive Can have multiple frontends serving media off a dedicated backend

MythTV Problem Users may not want to purchase a PC to sit next to their TVs PC’s are large and often unsightly Separate frontend/backend allows for a small, low power computer by the TV –Small general purpose computer are expensive

Desired Features MythTV communicating and playing video from a backend NTSC output on an S-Video cable to a television Finished product size of approximately 50 cubic inches

Accomplishments Software: –An x86 Gentoo image less than 64 mb With MythTV Frontend Compiled –A compiled Gumstix image with: Framebuffer and core system drivers < 10 mb X-Windows server DirectFB Graphics Library SDL Graphics Library Sample Framebuffer Graphics Applications

Accomplishments Hardware: –Board capable of converting digital RGB signals to drive a VGA monitor –Successfully connected the board to the Gumstix, displaying the contents of the framebuffer on a VGA monitor –Hardware meets space requirements

Design Process Base system: –Used Gumsitx as the base system Features: –400 MHz ARM Processor –64 MB of RAM –16 MB of internal storage –MMC/SD Slot for high capacity permanent storage –Built in Ethernet and audio capability Why: –Extremely small form factor –Low power, heat, and noise –Several features built in

Design Process Software: –Compiled Linux image using Gentoo for x86 architecture, with MythTV frontend included. –Attempted building Gentoo image for ARM processor, but found MythTV to be infeasible. –Created Gumstix image from scratch, manually building framebuffer drivers and core system programs. –Compiled and installed framebuffer testing applications to Gumstix. –Compiled and installed DirectFB and SDL graphics libraries for future development.

Design Process Hardware: –Initial design planned on utilizing Sigma Designs EM8620L or similar graphical processing unit –Second plan involved converting the Gumstix LCD controller output to S-Video Created circuit board utilizing Analog Devices ADV7120 and AD723 Intended to interface with Gumstix through a CPLD downsampler / interleaver

Hardware Design Initial Test: Display colored bars using signals generated from a CPLD –Could not generate proper NTSC signal Discovered output of ADV7120 can directly drive a VGA monitor –Successfully interfaced ADV7120 with Gumstix and VGA monitor

Conclusion With further work it may still be possible to convert the Gumstix LCD controller signals to an NTSC signal Due to the limitations of 16-bit color running MythTV or a movie player may not result in acceptable video quality Due to cross-compilation difficulties, getting MythTV to run on an ARM processor may be unfeasible anyway Compiled graphics libraries may allow for other media players to be compiled and executed in place of MythTV