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Hw2

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Hw2

  1. 1. Introduction to MPEG
  2. 2. Overview <ul><li>The Moving Picture Experts Group (MPEG)
  3. 3. standards for audio and video compression and transmission
  4. 4. Standards </li><ul><li>MPEG-1
  5. 5. MPEG-2
  6. 6. MPEG-4
  7. 7. MPEG-7
  8. 8. MPEG-21 </li></ul></ul>
  9. 9. MPEG-1 <ul><li>a standard for lossy compression of video and audio
  10. 10. MPEG-1 has become the most widely compatible lossy audio/video format in the world
  11. 11. Part 1 of the MPEG-1 standard covers systems, and is defined in ISO/IEC-11172-1. </li><ul><li>Elementary streams
  12. 12. Program streams
  13. 13. Multiplexing </li></ul></ul>
  14. 14. MPEG-1(cont.) <ul><li>Part 2 of the MPEG-1 standard covers video and is defined in ISO/IEC-11172-2. The design was heavily influenced by H.261. </li><ul><li>Color space
  15. 15. Resolution/Bitrate
  16. 16. Frame/picture/block types
  17. 17. Motion vectors
  18. 18. DCT
  19. 19. Quantization
  20. 20. Entropy coding </li></ul></ul>
  21. 21. MPEG-1(cont.) <ul><li>Part 3 of the MPEG-1 standard covers audio and is defined in ISO/IEC-11172-3 </li><ul><li>Layer I : Layer I uses a smaller 384-sample frame size for very low delay, and finer resolution.
  22. 22. Layer II : a lossy audio format designed to provide high quality at about 192 kbit/s for stereo sound
  23. 23. Layer III/MP3 : a lossy audio format designed to provide acceptable quality at about 64 kbit/s for monaural audio over single-channel (BRI) ISDN links, and 128 kbit/s for stereo sound. </li></ul></ul>
  24. 24. MPEG-1(cont.) <ul><li>Part 4 of the MPEG-1 standard covers conformance testing, and is defined in ISO/IEC-11172-4.
  25. 25. Part 5 of the MPEG-1 standard includes reference software, and is defined in ISO/IEC-11172-5.
  26. 26. Note that Mp3 NOT 「 MEPG3 」 ,means MPEG1 Layer 3 </li></ul>
  27. 27. MPEG-2 <ul><li>a standard for &quot;the generic coding of moving pictures and associated audio information&quot;.
  28. 28. a combination of </li><ul><li>lossy video compression
  29. 29. lossy audio data compression </li></ul><li>permit storage and transmission of movies using currently available storage media and transmission bandwidth. </li></ul>
  30. 30. MPEG-2(cont.) <ul><li>MPEG-2 is widely used as the format of digital television signals that are broadcast by terrestrial (over-the-air), cable, and direct broadcast satellite TV systems.
  31. 31. specifies the format of movies and other programs that are distributed on DVD and similar discs.
  32. 32. MPEG-2 evolved out of the shortcomings of MPEG-1. </li></ul>
  33. 33. MPEG-4 <ul><li>absorbs many of the features of MPEG-1 and MPEG-2 and other related standards
  34. 34. adding new features such as </li><ul><li>(extended) VRML support for 3D rendering
  35. 35. object-oriented composite files (including audio, video and VRML objects)
  36. 36. support for externally-specified Digital Rights Management
  37. 37. various types of interactivity </li></ul></ul>
  38. 38. MPEG-4(cont.) <ul><li>MPEG-4 was aimed primarily at low bit-rate video communications
  39. 39. left to individual developers to decide whether to implement the features of MPEG-4. </li></ul>
  40. 40. MPEG-7 <ul><li>a multimedia content description standard.
  41. 41. formally called Multimedia Content Description Interface.
  42. 42. The combination of MPEG-4 and MPEG-7 has been referred to as MPEG-47. </li></ul>
  43. 43. MPEG-7(cont.) <ul><li>It was designed to standardize: </li><ul><li>a set of Description Schemes (short DS in the standard) and Descriptors (short D in the standard)
  44. 44. a language to specify these schemes, called the Description Definition Language (short DDL in the standard)
  45. 45. a scheme for coding the description </li></ul></ul>
  46. 46. MPEG-21 <ul><li>aims at defining an open framework for multimedia applications.
  47. 47. MPEG-21 is ratified in the standard ISO/IEC 21000
  48. 48. MPEG-21 defines a &quot;Rights Expression Language&quot; standard as means of sharing digital rights/permissions/restrictions for digital content from content creator to content consumer. </li></ul>
  49. 49. MPEG-21(cont.) <ul><li>MPEG-21 is based on two essential concepts </li><ul><li>the definition of a fundamental unit of distribution
  50. 50. the definition of a fundamental unit of transaction(Digital Item ─ the concept of users interacting with them. </li></ul><li>MPEG-21 provides a framework in which one user interacts with another one, and the object of that interaction is a Digital Item. </li></ul>

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