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  Audio and Video Streaming By Nanda Ganesan, Ph.D. © Nanda Ganesan, All rights reserved
AUDIO STREAMING OVERVIEW <ul><li>Audio File Features </li></ul><ul><li>Audio Streaming Concept </li></ul><ul><li>Audio Str...
Audio File Features <ul><li>Audio file is a record of captured sound that can be played back </li></ul><ul><ul><li>The WAV...
The Wav File Format <ul><li>The wav file format is also known as the basic file format </li></ul><ul><ul><li>Somewhat simi...
Audio Streaming Concept .WAV .ASF, .WMA  Real Producer . RM Windows Media Encoder or  Real Producer  PC Audio Format  PC...
Audio Streaming <ul><li>Step1: Digitize audio </li></ul><ul><ul><li>PCM </li></ul></ul><ul><li>Step 2: Compress the digiti...
Pulse Code Modulation Values <ul><li>Sampling Frequency </li></ul><ul><ul><li>11,000 Hz for example </li></ul></ul><ul><li...
Streaming Process Digitize (PCM) Audio Digitized audio Streaming Software Streamed audio
Audio Streaming Advantages <ul><li>Low bandwidth and storage </li></ul><ul><li>Able to deliver audio in real time over a c...
Audio Streaming Applications <ul><li>Long-distance or automated seminars and training sessions  </li></ul><ul><li>Internet...
Audio Format: MPEG <ul><li>Moving Pictures Expert Format </li></ul><ul><ul><li>mp3 </li></ul></ul>
Audio Format: Apple Related <ul><li>Quicktime and other Macintosh related standards  </li></ul><ul><ul><li>.qt, .aif, .aif...
Audio Format: Unix Related <ul><li>au </li></ul><ul><li>snd  </li></ul>
Audio Streaming Products <ul><li>Window Media Technologies (Microsoft) </li></ul><ul><li>Real System (Real Networks) </li>...
Windows Media Technologies <ul><li>Windows Media Audio 9 Series </li></ul><ul><li>Windows Media Video 9 Series </li></ul><...
Windows Media Link <ul><li>http://www. microsoft .com/windows/ windowsmedia / </li></ul>
Windows Media Technologies (WMT) <ul><li>Windows Media Audio CODEC provides excellent quality at low bit rates </li></ul><...
Audio Comparison
Video Comparison
WMT Advantages <ul><li>Multiple Bit Rate and Multiple Language Support  </li></ul><ul><li>Variable speed playback </li></u...
Multiple Bit Rate and Multiple Language Support  <ul><li>With a single click of one file, the Windows Media Player 9 Serie...
Real Networks <ul><li>High quality streaming audio at all bandwidths on both the Internet and corporate Intranets. </li></...
Real System G2 Products & Advantages <ul><li>RealPlayer 8 </li></ul><ul><ul><li>Over 150 live radio stations built-in, sup...
RealSystem G2 Products & Advantages <ul><li>RealSlideshow 2 </li></ul><ul><ul><li>Combine pictures with music or speech, c...
Video Streaming <ul><li>Video Streaming Objective </li></ul><ul><li>Streaming Advantages </li></ul><ul><li>Video Streaming...
Video Streaming Objective <ul><li>The object is to overcome the negative effects of physical distance and network technolo...
Streaming Advantages <ul><li>Reduce setup time </li></ul><ul><li>Reduction in client storage requirement </li></ul><ul><li...
Video Streaming Architecture <ul><li>Content Creation/Capture </li></ul><ul><li>Content Management </li></ul><ul><li>Conte...
Video Capture <ul><li>Converting analog to video signals </li></ul><ul><ul><li>A special video capture card to convert the...
Content Management <ul><li>Critical in video server </li></ul><ul><li>The purpose including create, collect, catalog, orga...
Video Input Formats <ul><li>AVI </li></ul><ul><li>ActiveMovie </li></ul><ul><li>Cinepak </li></ul><ul><li>Indeo </li></ul>...
Video Formats AVI & ASF <ul><li>Developed by Microsoft </li></ul><ul><li>AVI (Audio Video Interleaved) </li></ul><ul><li>-...
Standard Window Size <ul><li>320X240 </li></ul><ul><li>640X480 </li></ul>
Frame Rates  <ul><li>4-6 fps </li></ul><ul><ul><li>Absolute minimum for video conferencing </li></ul></ul><ul><li>11-14 fp...
Codec (Compressor/Decompressor) <ul><li>Coding techniques to compress video data </li></ul><ul><li>The newest codec change...
Content Compression <ul><li>MPEG (A working group of ISO) </li></ul><ul><li>- The most common standard for video </li></ul...
MPEG-1 <ul><li>MPEG-1 was designed for coding progressive video at a transmission rate of about 1.5 million bits per secon...
MPEG-2 <ul><li>MPEG-2 was designed for coding interlaced images at transmission rates above 4 million bits per second.  </...
MPEG-3 <ul><li>A proposed MPEG-3 standard, intended for High Definition TV (HDTV), was merged with the MPEG-2 standard whe...
MPEG-4 <ul><li>An MPEG-4 standard is in the final stages of development and release.  </li></ul><ul><li>It is a much more ...
Major Products <ul><li>Microsoft Windows Media Technologies </li></ul><ul><li>http://www. microsoft .com/windows/ windowsm...
Comparison WMT –vs- RealSystem G2 <ul><li>Head to head comparison </li></ul><ul><li>Feature Comparison </li></ul><ul><li>M...
Comparison WMT –vs- RealSystem G2 <ul><li>Cost Analysis </li></ul><ul><li>- Prepared by Approach, Inc., </li></ul><ul><li>...
Audio Streaming Architecture <ul><li>Creating Audio File </li></ul><ul><li>Demonstration of Streaming Software </li></ul><...
Creating Audio File <ul><li>Record From File </li></ul><ul><ul><li>Audio files located in your hard drive </li></ul></ul><...
Installation of Streaming Software <ul><li>Windows Media Tools </li></ul><ul><ul><li>Windows Media Encoder </li></ul></ul>...
Windows Media Technologies http://www.microsoft.com/windows/windowsmedia Download Windows Media Tools
RealSystem G2 Download RealProducer   http://www.realnetworks.com/products/producer/
Playing Audio File <ul><li>Windows Media Player </li></ul><ul><li>RealPlayer </li></ul>
Windows Media Player 7 http://www.microsoft.com/windows/windowsmedia/
Download RealPlayer http://www.real.com/player/index
Real Player 7.0 Basic
Video Streaming Presentation <ul><li>Active Streaming Format (ASF) </li></ul><ul><li>- MS Defacto standard for streaming v...
Video Streaming <ul><li>Codec selections from Real Media. </li></ul>
Video Streaming <ul><li>Codec Selections from Windows Media. </li></ul>
Video Streaming <ul><li>Streaming with Real Producer. </li></ul><ul><li>Real Producer. </li></ul><ul><ul><li>-  C:Program ...
Video Streaming <ul><li>Streaming with Windows Media Encoder . </li></ul><ul><li>Windows Media. </li></ul><ul><ul><li>-  C...
Video Streaming <ul><li>Using Windows Media Player. </li></ul><ul><ul><li>-  C:Program FilesWindows Media Playermplayer2.e...
Video Streaming <ul><li>Streamed file size comparison. </li></ul><ul><li>-  C:WINDOWSEXPLORER.SCF </li></ul><ul><li>Unstre...
Video Streaming Statistics
Video Streaming Statistics
Video Streaming <ul><li>Live feed Video Capture. </li></ul><ul><ul><li>-  C:Program FilesLogitechLogitech  QuickCam  Quick...
Audio/Video Streaming Summary <ul><li>Capture Audio/Video </li></ul><ul><ul><li>Create your file </li></ul></ul><ul><li>In...
Audio/Video Streaming Summary <ul><li>Play the Audio Stream File </li></ul><ul><ul><li>Windows Media Player 7  </li></ul><...
The End
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Transcript of "Streaming Overview Final.ppt"

  1. 1. Audio and Video Streaming By Nanda Ganesan, Ph.D. © Nanda Ganesan, All rights reserved
  2. 2. AUDIO STREAMING OVERVIEW <ul><li>Audio File Features </li></ul><ul><li>Audio Streaming Concept </li></ul><ul><li>Audio Streaming Advantages </li></ul><ul><li>Audio Streaming Applications </li></ul><ul><li>Audio Streaming Format </li></ul><ul><li>Audio Streaming Products </li></ul>
  3. 3. Audio File Features <ul><li>Audio file is a record of captured sound that can be played back </li></ul><ul><ul><li>The WAV File is an example </li></ul></ul><ul><li>Audio files are compressed for storage and faster transmission </li></ul><ul><li>Requires high bandwidth to transfer across the network and the Internet </li></ul>
  4. 4. The Wav File Format <ul><li>The wav file format is also known as the basic file format </li></ul><ul><ul><li>Somewhat similar to the .bmp format for images </li></ul></ul><ul><li>Requires the highest storage compared to other compressed and streamed file formats </li></ul><ul><ul><li>Example: rm, wma etc. </li></ul></ul>
  5. 5. Audio Streaming Concept .WAV .ASF, .WMA Real Producer . RM Windows Media Encoder or Real Producer  PC Audio Format  PC Windows Media Streaming Software
  6. 6. Audio Streaming <ul><li>Step1: Digitize audio </li></ul><ul><ul><li>PCM </li></ul></ul><ul><li>Step 2: Compress the digitized audio </li></ul><ul><ul><li>Lowering the audio’s sampling rate </li></ul></ul><ul><ul><li>Filtering high frequencies </li></ul></ul><ul><ul><li>Performing other waveform transformation </li></ul></ul><ul><li>Ensure the continuous streaming of audio packets </li></ul>
  7. 7. Pulse Code Modulation Values <ul><li>Sampling Frequency </li></ul><ul><ul><li>11,000 Hz for example </li></ul></ul><ul><li>Sampling depth </li></ul><ul><ul><li>8 bits for example </li></ul></ul><ul><li>Channels </li></ul><ul><ul><li>Mono or stereo </li></ul></ul>
  8. 8. Streaming Process Digitize (PCM) Audio Digitized audio Streaming Software Streamed audio
  9. 9. Audio Streaming Advantages <ul><li>Low bandwidth and storage </li></ul><ul><li>Able to deliver audio in real time over a communication line </li></ul><ul><li>Efficient and effective delivery of audio over the Internet </li></ul>
  10. 10. Audio Streaming Applications <ul><li>Long-distance or automated seminars and training sessions </li></ul><ul><li>Internet music </li></ul><ul><li>Internet radio </li></ul><ul><li>Streamed audio for a variety of web and CD applications </li></ul>
  11. 11. Audio Format: MPEG <ul><li>Moving Pictures Expert Format </li></ul><ul><ul><li>mp3 </li></ul></ul>
  12. 12. Audio Format: Apple Related <ul><li>Quicktime and other Macintosh related standards </li></ul><ul><ul><li>.qt, .aif, .aifc, .aiff, .mov </li></ul></ul>
  13. 13. Audio Format: Unix Related <ul><li>au </li></ul><ul><li>snd </li></ul>
  14. 14. Audio Streaming Products <ul><li>Window Media Technologies (Microsoft) </li></ul><ul><li>Real System (Real Networks) </li></ul><ul><li>Shockwave Streaming Audio (Macromedia) </li></ul><ul><li>Linux based streaming products </li></ul>
  15. 15. Windows Media Technologies <ul><li>Windows Media Audio 9 Series </li></ul><ul><li>Windows Media Video 9 Series </li></ul><ul><li>Windows Media Encoder 9 Series </li></ul><ul><li>Windows Media Services 9 Series </li></ul><ul><li>Windows Media Player 9 Series </li></ul><ul><li>Windows Media Rights Manager 9 Series </li></ul><ul><li>Windows Media 9 Series SDK </li></ul>
  16. 16. Windows Media Link <ul><li>http://www. microsoft .com/windows/ windowsmedia / </li></ul>
  17. 17. Windows Media Technologies (WMT) <ul><li>Windows Media Audio CODEC provides excellent quality at low bit rates </li></ul><ul><li>Integration with other Microsoft products (Windows NT Server, Microsoft Site Server, Microsoft BackOffice) </li></ul><ul><li>Digital rights management </li></ul><ul><li>Advanced Compression Technology Broadcasting </li></ul>
  18. 18. Audio Comparison
  19. 19. Video Comparison
  20. 20. WMT Advantages <ul><li>Multiple Bit Rate and Multiple Language Support </li></ul><ul><li>Variable speed playback </li></ul><ul><li>Highly compressed audio and video </li></ul><ul><li>Audio CODEC is optimized for dial-up rates </li></ul><ul><li>Digital 5.1 surround sound CODEC </li></ul><ul><li>Lossless audio compression </li></ul><ul><li>Good scalability to larger audience </li></ul><ul><li>Live digital rights management </li></ul><ul><li>Support for Plug-in (C++ etc.) </li></ul><ul><li>(For further info: ) </li></ul>
  21. 21. Multiple Bit Rate and Multiple Language Support <ul><li>With a single click of one file, the Windows Media Player 9 Series can automatically pick the best video size and audio quality to stream, based on the current connection speed – and it dynamically adapts during streaming. </li></ul><ul><li>The player can automatically choose the preferred audio language, or the user can select or change languages on-the-fly during playback. </li></ul><ul><li>(source: Microsoft) </li></ul>
  22. 22. Real Networks <ul><li>High quality streaming audio at all bandwidths on both the Internet and corporate Intranets. </li></ul><ul><li>Support realtime and on-demand, all sounds (stereo and mono) </li></ul><ul><li>Take advantage of key features of Window 2000 (load balancing, clustering, stability) </li></ul><ul><li>Operating systems such as Window NT, Linux, Sun Solaris etc. are all supported </li></ul>
  23. 23. Real System G2 Products & Advantages <ul><li>RealPlayer 8 </li></ul><ul><ul><li>Over 150 live radio stations built-in, superb audio </li></ul></ul><ul><li>RealProducer 7 </li></ul><ul><ul><li>Streaming Software; Efficient encoding; Reach the widest possible audience; choice of operating systems </li></ul></ul><ul><li>RealPresenter G2 </li></ul><ul><ul><li>Live/recorded capability; Presentation Manager </li></ul></ul>
  24. 24. RealSystem G2 Products & Advantages <ul><li>RealSlideshow 2 </li></ul><ul><ul><li>Combine pictures with music or speech, customize the layout of presentation </li></ul></ul><ul><li>RealServer 7 </li></ul><ul><ul><li>60 simultaneous sessions of live or on-demand streaming; Near CD quality Internet audio </li></ul></ul><ul><li>Free download at: </li></ul><ul><ul><li>http://www.realnetworks.com/products/ </li></ul></ul>
  25. 25. Video Streaming <ul><li>Video Streaming Objective </li></ul><ul><li>Streaming Advantages </li></ul><ul><li>Video Streaming Architecture </li></ul><ul><li>Compression and Decompression-codec </li></ul><ul><li>MPEG 1-4 Introduction </li></ul><ul><li>Major Products and Features Comparison </li></ul>
  26. 26. Video Streaming Objective <ul><li>The object is to overcome the negative effects of physical distance and network technology limitation. </li></ul>
  27. 27. Streaming Advantages <ul><li>Reduce setup time </li></ul><ul><li>Reduction in client storage requirement </li></ul><ul><li>Video can be viewed in real time </li></ul><ul><li>Transmission signals over low bandwidth facilities </li></ul>
  28. 28. Video Streaming Architecture <ul><li>Content Creation/Capture </li></ul><ul><li>Content Management </li></ul><ul><li>Content Formatting (Compression) </li></ul><ul><li>Delivery </li></ul><ul><li>Distribution </li></ul><ul><li>Presentation (Viewing) </li></ul><ul><li>View Control </li></ul>
  29. 29. Video Capture <ul><li>Converting analog to video signals </li></ul><ul><ul><li>A special video capture card to convert the analog signals to digital form and compresses the data. </li></ul></ul><ul><ul><li>Also digital video devices that can capture images and transfer to a computer </li></ul></ul>
  30. 30. Content Management <ul><li>Critical in video server </li></ul><ul><li>The purpose including create, collect, catalog, organize, store, and access to massive multimedia information database </li></ul>
  31. 31. Video Input Formats <ul><li>AVI </li></ul><ul><li>ActiveMovie </li></ul><ul><li>Cinepak </li></ul><ul><li>Indeo </li></ul><ul><li>motion-JPEG </li></ul><ul><li>MPEG </li></ul><ul><li>QuickTime </li></ul><ul><li>RealVideo </li></ul><ul><li>Video for Windows </li></ul><ul><li>XGA </li></ul>
  32. 32. Video Formats AVI & ASF <ul><li>Developed by Microsoft </li></ul><ul><li>AVI (Audio Video Interleaved) </li></ul><ul><li>- limited to 320x240 resolution </li></ul><ul><li>- 30 frames per second </li></ul><ul><li>ASF (Advanced Streaming Format) </li></ul><ul><li>- Has been submitted to ISO for standardization </li></ul><ul><li>- Expected to replace AVI format </li></ul>
  33. 33. Standard Window Size <ul><li>320X240 </li></ul><ul><li>640X480 </li></ul>
  34. 34. Frame Rates <ul><li>4-6 fps </li></ul><ul><ul><li>Absolute minimum for video conferencing </li></ul></ul><ul><li>11-14 fps </li></ul><ul><ul><li>The norm for video conferencing </li></ul></ul><ul><li>30 fps </li></ul><ul><ul><li>Full motion video </li></ul></ul>
  35. 35. Codec (Compressor/Decompressor) <ul><li>Coding techniques to compress video data </li></ul><ul><li>The newest codec change their sampling rate as they run </li></ul><ul><li>Choice of codec is the biggest factor to determine the bandwidth needed to connect the server and receive content </li></ul><ul><li>Many of the codecs follow international standards </li></ul>
  36. 36. Content Compression <ul><li>MPEG (A working group of ISO) </li></ul><ul><li>- The most common standard for video </li></ul><ul><li>compression and file formats </li></ul><ul><li>- Generally produce better quality video than other </li></ul><ul><li>formats </li></ul><ul><li>- High compression rate </li></ul><ul><li>- MPEG1, MPEG2, MPEG3 and MPEG4 </li></ul>
  37. 37. MPEG-1 <ul><li>MPEG-1 was designed for coding progressive video at a transmission rate of about 1.5 million bits per second. </li></ul><ul><li>It was designed specifically for Video-CD and CD-i media. </li></ul><ul><li>MPEG-1 audio layer-3 (MP3) has also evolved from early MPEG work. </li></ul>
  38. 38. MPEG-2 <ul><li>MPEG-2 was designed for coding interlaced images at transmission rates above 4 million bits per second. </li></ul><ul><li>MPEG-2 is used for digital TV broadcast and </li></ul><ul><li>DVD. </li></ul><ul><li>An MPEG-2 player can handle MPEG-1 data as well. </li></ul>
  39. 39. MPEG-3 <ul><li>A proposed MPEG-3 standard, intended for High Definition TV (HDTV), was merged with the MPEG-2 standard when it became apparent that the MPEG-2 standard met the HDTV requirements. </li></ul>
  40. 40. MPEG-4 <ul><li>An MPEG-4 standard is in the final stages of development and release. </li></ul><ul><li>It is a much more ambitious standard and addresses speech and video synthesis, fractal geometry, computer visualization, and an artificial intelligence (AI) approach to reconstructing images. </li></ul>
  41. 41. Major Products <ul><li>Microsoft Windows Media Technologies </li></ul><ul><li>http://www. microsoft .com/windows/ windowsmedia / </li></ul><ul><li>RealSystem G2 </li></ul><ul><li>http://www. realnetwork .com </li></ul>
  42. 42. Comparison WMT –vs- RealSystem G2 <ul><li>Head to head comparison </li></ul><ul><li>Feature Comparison </li></ul><ul><li>M ore Information http://www. microsoft .com/windows/ windowsmedia / </li></ul>
  43. 43. Comparison WMT –vs- RealSystem G2 <ul><li>Cost Analysis </li></ul><ul><li>- Prepared by Approach, Inc., </li></ul><ul><li>Key findings </li></ul><ul><li>- Both streaming products results in positive </li></ul><ul><li>returns on investment </li></ul><ul><li>- Microsoft solution is more economical than the </li></ul><ul><li>RealNetwork solution </li></ul><ul><li>Download in Word format </li></ul>
  44. 44. Audio Streaming Architecture <ul><li>Creating Audio File </li></ul><ul><li>Demonstration of Streaming Software </li></ul><ul><li>Demo of Streaming Process </li></ul><ul><ul><li>Windows Media Encoder </li></ul></ul><ul><ul><li>RealProducer 7 Basic </li></ul></ul><ul><li>Play the Audio File </li></ul>
  45. 45. Creating Audio File <ul><li>Record From File </li></ul><ul><ul><li>Audio files located in your hard drive </li></ul></ul><ul><li>Record Form Media Device </li></ul><ul><ul><li>Media device such as Microphone, CD Player, PC Camera, etc. </li></ul></ul><ul><li>Live Broadcast </li></ul><ul><ul><li>Broadcast live media stream from your computer </li></ul></ul>
  46. 46. Installation of Streaming Software <ul><li>Windows Media Tools </li></ul><ul><ul><li>Windows Media Encoder </li></ul></ul><ul><li>RealSystems G2 </li></ul><ul><ul><li>RealProducer 7 Basic </li></ul></ul>
  47. 47. Windows Media Technologies http://www.microsoft.com/windows/windowsmedia Download Windows Media Tools
  48. 48. RealSystem G2 Download RealProducer http://www.realnetworks.com/products/producer/
  49. 49. Playing Audio File <ul><li>Windows Media Player </li></ul><ul><li>RealPlayer </li></ul>
  50. 50. Windows Media Player 7 http://www.microsoft.com/windows/windowsmedia/
  51. 51. Download RealPlayer http://www.real.com/player/index
  52. 52. Real Player 7.0 Basic
  53. 53. Video Streaming Presentation <ul><li>Active Streaming Format (ASF) </li></ul><ul><li>- MS Defacto standard for streaming video. </li></ul><ul><li>Real Media (RM) </li></ul><ul><li>- Real’s standard for streaming video </li></ul>
  54. 54. Video Streaming <ul><li>Codec selections from Real Media. </li></ul>
  55. 55. Video Streaming <ul><li>Codec Selections from Windows Media. </li></ul>
  56. 56. Video Streaming <ul><li>Streaming with Real Producer. </li></ul><ul><li>Real Producer. </li></ul><ul><ul><li>- C:Program FilesREAL RealProducer realprod .exe </li></ul></ul>
  57. 57. Video Streaming <ul><li>Streaming with Windows Media Encoder . </li></ul><ul><li>Windows Media. </li></ul><ul><ul><li>- C:Program FilesWindows Media ComponentsTools NsRex .exe </li></ul></ul>
  58. 58. Video Streaming <ul><li>Using Windows Media Player. </li></ul><ul><ul><li>- C:Program FilesWindows Media Playermplayer2.exe </li></ul></ul>
  59. 59. Video Streaming <ul><li>Streamed file size comparison. </li></ul><ul><li>- C:WINDOWSEXPLORER.SCF </li></ul><ul><li>Unstreamed *.AVI file = 155,290 KB </li></ul><ul><li>RealMedia Streamed file *.RM = 483 KB </li></ul><ul><li>Windows Media Streamed file *.ASF = 1,283 KB </li></ul>
  60. 60. Video Streaming Statistics
  61. 61. Video Streaming Statistics
  62. 62. Video Streaming <ul><li>Live feed Video Capture. </li></ul><ul><ul><li>- C:Program FilesLogitechLogitech QuickCam QuickCam .exe </li></ul></ul><ul><li>Stream from live feed. </li></ul><ul><li>- C:Program FilesREAL RealProducer realprod .exe </li></ul><ul><li>- C:Program FilesWindows Media ComponentsTools NsRex .exe </li></ul>
  63. 63. Audio/Video Streaming Summary <ul><li>Capture Audio/Video </li></ul><ul><ul><li>Create your file </li></ul></ul><ul><li>Install the streaming software </li></ul><ul><ul><li>Windows Media Tools http://www. microsoft .com/windows/ windowsmedia / </li></ul></ul><ul><ul><li>RealProducer 7 Basic http://www. realnetworks .com/products/ </li></ul></ul>
  64. 64. Audio/Video Streaming Summary <ul><li>Play the Audio Stream File </li></ul><ul><ul><li>Windows Media Player 7 </li></ul></ul><ul><ul><li>http://www.microsoft.com/windows/windowsmedia/ </li></ul></ul><ul><ul><li>RealPlayer 7 Basic </li></ul></ul><ul><ul><li>http://www.real.com/player/index </li></ul></ul>
  65. 65. The End
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