• Like
MP4: Help Session Slides
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

MP4: Help Session Slides

  • 172 views
Published

 

  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
    Be the first to like this
No Downloads

Views

Total Views
172
On SlideShare
0
From Embeds
0
Number of Embeds
0

Actions

Shares
Downloads
1
Comments
0
Likes
0

Embeds 0

No embeds

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
    No notes for slide

Transcript

  • 1. MP4: Synchronization and GUI Short Tutorial 4/14/2008
  • 2. Outline
    • Scenarios
    • Media synchronization
    • Graphical user interface
  • 3. Scenario A Server 1 Proxy Client 1 Server 2 audio1 file video1 file audio2 file video2 file PLAY audio1/video1 or PLAY audio2/video2
  • 4. Scenario B Server 1 Proxy Client 1 Client 2 Server 2 audio1 file video1 file audio2 file video2 file PLAY audio1/video1 or PLAY audio2/video2 PLAY audio1/video1 or PLAY audio2/video2
  • 5. Media Synchronization
    • Audio and video files must be able to clearly demonstrate synchronization
      • Speeches and singing are good examples requiring lip synchronization
    • Each audio sample or video frame should have a timestamp
    • Audio is leading time synchronization stream
      • Video (and any other stream) should be synchronized with respect to audio
    • Recommend synchronization point each second
      • Might need to speed up or slow down video relative to the audio
  • 6. Media Synchronization 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 0 1 2 3 4 5 6 7 8 9 10 11 audio stream 3 samples/sec video stream 2 frames/sec Synchronization Points audio = 3 video = 2 audio = 6 video = 4 audio = 9 video = 6 audio = 12 video = 8 audio = 15 video = 10
  • 7. Media Synchronization audio stream 3 samples/sec video stream 2 frames/sec Synchronization Points audio = 3 video = 2 audio = 6 video = 4 audio = 9 video = 5 audio = 12 video = 8 audio = 15 video = 10 DROPPED VIDEO FRAME 6 TO CATCH UP 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 0 1 2 3 4 6 5 7 8 9 10 11
  • 8. Graphical User Interface
    • Requires creativity
    • Groups are free to use their own original design
    • Should support many operations common to video-on-demand services
    • Should display meta-data
      • Proxy address and port
      • Audio/video characteristics
        • Sample rate
        • Frame rate
  • 9. GUI Operations
    • MENU
      • List all of the available A/V streams
      • Might use to implement channel switching
    • PLAY
      • Play the selected A/V stream
    • STOP
      • Stop the selected A/V stream
    • PAUSE
      • Pause the selected A/V stream
    • Option buttons displaying channel number
      • Two movie channels with buttons “1” and “2”
      • Better choice for easy channel switching
  • 10. Example GUI Proxy address: csil-core25 port: 9090 Audio rate: 24 Kbps Video rate: 1 Mbps PLAY STOP PAUSE MENU Channel Buttons: 1 2 Note: this is just an example, not a requirement
  • 11.
    • Drop-down menu could display the following channels for selection
    • Buttons could offer users shortcut
    Channel Switching Channel 1: audio1.wav / video1.mjpg Channel 2: audio2.wav / video2.mjpg