Multimedia Time Warping System. Akiko Campbell Presentation-2 Summer/2004

Transcription

1 Multimedia Time Warping System Akiko Campbell Presentation-2 Summer/2004

2 Outline Overview Facts Features Multimedia Time Warping System Conclusion Effect of TiVo on VoD

3 Overview Facts A Linux box that sits on the TV set Media on Demand in Client Paradigm. A Pioneer in Television Service for DVR (Digital Video Recorders). 703,000 service subscribers. Service & Technology Revenue: 60.2 million (January 31, 2003)

4 Overview Features Pause/Rewind/Replay/ Slow Motion Live TV. Fast Forward to the current scene. Scheduled Recording. Search Programs.

5 US 6,233,389 BI Patent Title: Multimedia time warping system Patent No: US 6,233,389 BI Date of Patent: May 15, 2001 Assignee: Barton, et al.

6 Highlights US 6,233,389 BI View a TV broadcast program and instantly review previous scenes within the program. Store programs while watching or reviewing another program. View stored programs with: Play, Pause Reverse, Fast Forward Fast/Slow Reverse Play, Fast/Slow Play Index

7 Key Ideas US 6,233,389 BI 1. Convert: : TV input streams MPEG. 2. Parse: : MPEG Video & Audio components. 3. Store: : components temporary buffers & storage. 4. Event: : record type of event (audio vs. video), location, and timestamp. 6. Manipulate: : extract components from storage, reassemble into MPEG stream, send to decoder. 7. Decode: : convert MPEG stream into TV output signals.

8 Architecture Input Module: 101 TV input streams Analog: NTSC, PAL broadcast Digital (MPEG2): DSS, DBS, ATSC Produce MPEG streams, using VBR encoding Pass MPEG streams to 102

9 Architecture Media Switch: 102 Mediate among CPU, memory, storage. Buffer MPEG stream into memory. Send stream to 103. (user watching Live) Write to 105.

10 Architecture Output Module: 103 Produce analog TV signal. Contain: MPEG Decoder On-Screen Display (OSD) generator Analog TV encoder Audio logic

11 Parser: 705 Media Switch: 701 Input Stream flows through Parser. Parser divides Input Stream into segments.

12 Media Switch: Parser Segmentation Stream 301 Video 302, 305, 306 Audio 303, 304, 307 Separate 302, 305, 306 into Video 308 Separate 303, 304, 304 into Audio 309 Why? Separate decoders used to convert MPEG elements back into audio & video analog components

13 Media Switch: Parser Segmentation Timestamp Media Switch Enables program to associate time with each segment (timestamp) Monotonically Increasing. Start at 0 at each system boot.

14 Media Switch: Parser Segmentation Search Index on Timestamp Stream stored as a sequence of fixed- size segment.

15 Media Switch: Parser Stream Parsing Example Look for MPEG distinguished events. Find a video event. Direct video event to DMA engine buffers up data in video buffer 410. Direct an event to DMA engine 405.

16 Media Switch: Buffers System Interrupt Read event buffer 602 Generate logical segments 603 (-> > parsed MPEG 615) Continue to collect 603 until limit Generate a new buffer: Packetized Elementary Stream (PES) buffer Pass new PES to other components (e.g.) Decoder, Storage

17 Data Processing Logical Constructs Source Produce data. Transform Allocate buffers. Queue data. Processe data. Sink Consume buffered data.

18 Example: Pause Data Processing Control Object 917 sends Pause event to Sink 903. Sink 903 stops asking for new buffers. Current Pointer 920 stays where it s at. 917 sends Play event to resumes to take new buffers, starting with the same 920.

19 Data Processing Example: Fast Forward/Reverse Control Object 917 sends Fast Forward event to Transform 902, telling it to move forward 2 seconds. 902 sends Reset event to 903 to flush queued data/state in decoder. Current Pointer 920 moves 3 buffers forward. Sink 903 obtains new buffers, starting with the forwarded 920.

20 Conclusion Multimedia Time Warping System Signal Converter: analog digital. Data storage, manipulation device. TV viewing experience in the manner demanded by each viewer. Pause and be absent. Replay missed sections. Fast forward commercials.

21 Conclusion Effect of TiVo on VoD Is Pay Per View going to survive? Record movies and burn them onto Disks/DVD s. Convenience of Commercial Skipping vs. Copy Right Infringement. TiVo strictly with TV programs. VoD for net meeting, conferencing, etc.

22 References Multimedia time warping system United States Patent Application Kind Code A1, Patent No: US 6,233,389 BI, Barton, James M. et al. October 10, 2002 TiVo Website