Overview
Multimedia Center (MMC) is an integrated suite of software applications designed to provide the ultimate multimedia playback experience.

I had critical responsibilites in Closed Captioning, Teletext and Channel Management. The development technologies included C, C++, COM, MFC, COM, ATL, GDI, GDI+, DirectShow, DirectX, multi-threading.

For more information on the Multimedia Center suite click here.

Closed Captioning
Closed captioning (CC) is a television service used to show text captions during a broadcast. As the show plays text captions are shown on the display. The captions typically are used to transcribe the show for the benefit of the deaf, hearing-impaired or as an educational aid in learning to read.

I was responsible several Closed Captioning features:
  • VBI Decoder - a DirectShow filter used to sample VBI scanlines
  • CC Decoder - a DirectShow filter used to decode CC two-byte packets from the VBI data
  • CC Renderer - a DirectShow filter used to render captions over video
  • CC Database Search – Search the Closed Caption text during TV-on-Demand™ sessions to create instant replay
Video-In
Each TV Wonder, All-in-Wonder, and VIVO graphics cards that ATI sells feature an input dongle used to recieve video-in (S-Video and Composite). Any S-Video or Composite device can be connected and watched on a computer using MMC. For example, this allows users to record their films to DVD and play their Xbox on a computer. I managed the development of the video-in functionality in MMC.

In addition to providing Video-In functionality to MMC I architected a Microsoft Media Center (MCE) plug-in to add Video-In capability to MCE.

Teletext
Teletext is a text-based information service provided in television broadcasts. Broadcasters use Teletext to send text-based information to their viewers (sporting news, weather updates, TV guide, subtitles). Teletext data is sent over the VBI scanlines.

I was a key contributor to managing, designing and implementing the Teletext project. This included sampling the VBI data, decoding the Teletext packets, and a custom rendering engine.

The Teletext implemenation consisted of multiple DirectShow filters - a VBI decoder, a Teletext decoder, an optional Teletext To Closed Captions filter (used to convert Teletext subtitles in two-byte Closed Captions), and a rendering filter.

Channel Management
I was the architect for Channel Management for the analog and digital TV functionality.

Specific accomplishments include:
  • Designed algorithms for channel scanning
  • Designed algorithms for manually adding channels
  • Fine-tuning based on signal strength, PLL offsets, decoder quality
  • Object-oriented architecture used to abstract differences in tuner and video decoder standards (NTSC/PAL/SECAM/ATSC/DVB-T)
  • Object-oriented architecture used to seperate DirectShow and driver interfaces from main application
  • Parsing SI data for DVB-T channels
  • Parsing PSIP data for ATSC channels

Top of Page