Preserving Audiovisual Materials (LIS 198-Digital Preservation)

Download Preserving Audiovisual Materials (LIS 198-Digital Preservation)

Post on 23-Jun-2015

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A presentation on the digital preservation of audiovisual materials, including a brief history of media formats and file types, among others. It's a bit of a rushed work, I admit, plus the text designs are not as smooth as before I converted the PPT to PDF format.

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<ul><li> 1. preservingmaterials </li></ul> <p> 2. what arematerials? 3. audiovisualare surrogate 4. history 5. 2 Quad (1956)TCR 100 Quad (1969)UV 340 (1964) 6. Panasonic video cartridge (1969)Philips video recorder (1970)U-Matic(1971) 7. V-Cord (1972)Betamax(1975)VHS (1976) 8. D-2 (1988)Hi8 (1989)Digital betacam(1993) 9. Digital S (1995) 10. -2 (1988)Hi8 (1989)Digital betacam(1993) 11. -2 (1988)1992 12. -2 (1988)1997 : RM 13. -2 (1988) VOBASF 14. 2001- presentOCGMP4FLVMOVMKV3GP 15. indigital 16. signal recording of a signal onto a carrier 17. digitization digital preservation of the digitized signal 18. via 19. you 20. computerplayback device video cassette recorder 21. LEFT: The Avid Dazzle Video Creator Plus HD ($89/P4500) captures video. RIGHT: Pinnacles Studio MovieBoxHD ($100/P5000) is a similar capture device. 22. LEFT: The Avid Dazzle Video Creator Plus HD ($89/P4500) captures video. RIGHT: Pinnacles Studio MovieBoxHD ($100/P5000) is a similar capture device. 23. LEFT: The Avid Dazzle Video Creator Plus HD ($89/P4500) captures video. RIGHT: Pinnacles Studio MovieBoxHD ($100/P5000) is a similar capture device. 24. LEFT: The Avid Dazzle Video Creator Plus HD ($89/P4500) captures video. RIGHT: Pinnacles Studio MovieBoxHD ($100/P5000) is a similar capture device. 25. LEFT: The Avid Dazzle Video Creator Plus HD ($89/P4500) captures video. RIGHT: Pinnacles Studio MovieBoxHD ($100/P5000) is a similar capture device. 26. properties 27. resolution-number of pixels present in the images of the video-determines whether your video is standard definition or high def. 28. size-pixel dimension of the frame 29. aspect ratio-Ratio of width to height 30. frame rates-speed at which the frames are captured and intended for playback 31. bit rate-or data rate-amount of data used to describe the video portion of the file 32. bit rate-typically measured in per second units then in KB,MB,GB-higher bit rate, better quality (in general) 33. codec 34. properties 35. sampling rate-how often the audio is sampled when convertedfrom analog to digital 36. number of channelsEither coming from single (mono) or multiple channels (stereo) 37. codec 38. what is a 39. container VScodec 40. Describes structure of the file 41. Short for coder/decoderCompressor or decompressor-Way of encoding videointo a stream of bytes-Chief determinatorof quality 42. Container as the file itself. Codec as its contents. Impt. to realize: -most good container formats can hold many codecs 43. Describe both!Example:MOV file containing H.264 data 44. Problem: Common use of terms Confusion and imprecision 45. Even more confusing:-both describes codec and containerExample:mpeg-4 46. Windows media video-can be streamed across the internet-when WM server: viewed before entire file-windows media player-internet streaming server 47. Audio video interleave-Windows Player (ex. WMP)-uncompressed: high quality video-internet: entire file must be downloaded-stored on local hard disk or CDROM 48. Apple QuicktimeMovie-Apple QuicktimeMovie Player-viewed before entire file-streamed across internet-depends on compression 49. Motion Picture Experts Group-provide VHS quality movies or better-MPEG player-entire file must be downloaded 50. -Mpeg1 = VHSMpeg2better than VHS; used for DVDMpeg4best quality 51. Real Media-RealPlayer-viewed before the file-high compression but at a cost to quality 52. -makes a file smaller-decoded file is unaltered after decompression has taken place-by using a scheme known as run length encoding 53. Example: -Animation codec (which is typically used for archiving or transferring files), have a low compression ratio-Usually, its no more than 2:1. 54. -you lose some image, video, or audio information. -bit tricky because good lossycompression is a balancing act between quality, data rate/file size, colordepth, and fluid motion-Almost every video compression scheme is lossy 55. -Lossycompression schemes like H.264 (used on Canon video DSLRs) can have compression ratios of more than 100:1. -With video workflows, compression can be applied (or removed) at several stages.</p>