Video Conferenceing demo System for Conferencing between PC and TI DSP development board

• Requirements

MCCI requires Acme Technologies Pvt. Ltd. to develop a Videoconferencing demo system using PC/Laptop and a suitable board with CCD/CMOS camera, LCD, microphone and speaker.
Communication between PC/Laptop and "Device" will be using USB.

• Challenges

  • To achieve synchronization between video and speech playback
  • Multiple tasks handling viz video decoder, video encoder, audio encoding and decoding, video display and capture, and audio record and playback and USB transmit and receive.

• Solution

  • Environment

  OS	Windows Code Composer Studio
  Language/Platform	PC TI 6416 DSP
  Development model	Incremental development model

  • Features

    • Speech Codec: ITU G.723.1
      • 8 KHz Sampling rate
      • 5.3 and 6.3 kbps stream
    • Video Codec: ITU H.264
      • Baseline Profile
      • QCIF resolution
      • YUV 420
    • Systems: Own designed system layer implementation
    • Video Display and Capture via D3's CDK
    • Speech Capture and playback via onboard codec
    • USB capability for data transfer between PC and board
    • Graphical user-interface
      • Start Communication between PC and board
      • Audio Capture
      • Both local and remote visual data display

  • Description

    Since the requirements given to us were brief, we form the specifications by ourselves. During our study, we considered ARM9 based platform first. This is because we at acmet have used these platforms in many projects so many of our engineers have experience. However, it was found ARM9 processor is inadequate for these tasks due to the MCPS requirements for the implementation. So we decided on TI DSP board for our development since TI 6416 DSK at 600 MHz was sufficient for the application. Moreover the DSK lagged video input/output and USB port for data transfer. Therefore Camera Developer Kit (CDK) daughter card from D3 Engineering was purchased which added video input/output capability and USB port to board side of development.

    The development was done in two phases. Initial phase dealt with speech conferencing only since CDK was not available. The data transfer was done via RTDX. Video side development for porting and optimization to certain extent was carried out in parallel.

    The GUI modules gave an interface in initiating the process of conferencing as well controlling the audio/video devices for PC side.

    Second phase was full fledged Video Conferencing in which CDK was integrated with DSK.