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Captioning Digital Multimedia

Captioning Digital Multimedia. Geoff Freed Carl and Ruth Shapiro Family National Center for Accessible Media (NCAM) WGBH Educational Foundation http://ncam.wgbh.org. What to expect. Part I: Brief history; current state Part II: How it ’ s done editors style

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Captioning Digital Multimedia

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  1. Captioning Digital Multimedia Geoff Freed Carl and Ruth Shapiro Family National Center for Accessible Media (NCAM) WGBH Educational Foundation http://ncam.wgbh.org

  2. What to expect • Part I: Brief history; current state • Part II: How it’s done • editors • style • speed; convenience; quality • Part III: What’s next • formats • standards • recommendations • regulations

  3. About NCAM • Carl and Ruth Shapiro Family National Center for Accessible Media at the WGBH Educational Foundation (NCAM); http://ncam.wgbh.org • Part of the Media Access Group • The Caption Center (1972) • Descriptive Video Service (1990) • NCAM (1991)

  4. About NCAM 4 • R&D facility with the mission to make electronic media of all types accessible to people with sensory impairments • Work funded by federal grants, private foundations and strategic partners large and small • Expertise in on-line accessibility of all kinds (Web, multimedia, PDF, captioning, description, etc.) • Expertise in standards and guidelines (Section 508, WCAG, SMIL, ATSC, SMPTE, TTML, PDF, Flash, e-books/textbooks, image description, etc.)

  5. Part I: General Information

  6. What are captions?

  7. What are captions?

  8. What are captions?

  9. What are captions? • A visual representation of spoken narration or dialogue • Indicate important non-speech information: • sound effects, music, laughter • speaker identification • Synchronized to appear simultaneously with audio • Displayed in either pop-on or roll-up styles • In some countries, captions are called subtitles

  10. What are captions? • Captions and foreign-language subtitles are not the same thing • captions contain information in addition to narration and dialog; subtitles do not • captions are frequently positioned on the screen to indicate who is speaking; subtitles are not

  11. What are captions? • Captions can be closed or open: • closed captions can be turned on and off by the user • open captions are visible to everyone and cannot be turned off • QuickTime Player, iTunes, Apple mobile devices, RealPlayer, Flash, Silverlight and Windows Media Player all provide caption controls • some are custom, some are not • HTML5 introduces browser playback and control

  12. What about transcripts? • A transcript provides a text version of the audio track • a transcript is useful for creating captions • a transcript is a by-product of the captioning process • Transcripts should be considered a supplement to, not a replacement for, synchronized captions

  13. Captions can be displayed by allmajor multimedia players • QuickTime (embedded or external track/QTtext format) translucent overlay transparent overlay below the video region

  14. Captions can be displayed by allmajor multimedia players • QuickTime or iTunes (embedded track/SCC)

  15. Apple devices: iTunes

  16. Apple devices: iTunes

  17. Captions can be displayed by allmajor multimedia players • RealPlayer (external track; RealText) transparent overlay below the video region

  18. Captions can be displayed by allmajor multimedia players • Windows Media Player (external track; SAMI)

  19. Captions can be displayed by allmajor multimedia players • Flash (ccPlayer; TTML)

  20. Apple devices/SCC captions iPod nano iPhone/iPod touch/iPad

  21. Captions can be displayed by allmajor multimedia players • Some BlackBerry smartphones

  22. More and more on-line programming is captioned • ABC.com • Hulu.com • Hulu desktop • MTV • NBC.com • Netflix Instant Play • YouTube • others

  23. On-line customization • Some players allow customized views • YouTube (no account required) • Hulu (account required to save preferences)

  24. Part IIa: How It’s Done/General Rules CC University (the abbreviated course)

  25. Authoring captions • The most important aspect of caption writing is not… • software • technical format • delivery • UI

  26. Authoring captions • The most important aspect of caption writing is… accuracy • accurate transcription • accurate spelling • accurate editing • accurate formatting • accurate timing • accurate reviewing • Speed, convenience/quality

  27. Authoring captions Example 1 Example 2

  28. Authoring captions • Most caption-authoring applications follow the same basic procedure • transcribe audio • external transcription/import is usually easier (if permitted) • format and edit the text • divide text into discrete captions • divide rows within captions • edit if/as necessary • time the captions • verbatim vs edited • review; export

  29. Authoring captions: transcription • Accurately represent what is spoken • spelling, spelling, spelling • don’t add information • don’t edit unless there is reason to do so • reading level; special vocabulary • “there’s three things…” vs “going to/gonna” • fillers • don’t censor • indicate different speakers when necessary • indicate sound effects when necessary • Generally speaking, it’s faster to transcribe into a text editor and import the text into the caption editor

  30. Authoring captions: formatting • Make the captions easy to read • use appropriately sized fonts • use fonts that are easy to read • sans serif vs serif • open characteristics • break rows in logical places • break captions in logical places • end punctuation • natural pauses • Formatting is especially important for small-screen readability

  31. Authoring captions: timing • Time the captions to appear when corresponding words are spoken • lead/lag +/- one second if it is appropriate for speed • take advantage of pauses (to an extent) • align with shot changes (+/- one second) for a cleaner appearance • Verbatim timing is expected unless there is a reason to do otherwise • language level/comprehension

  32. Authoring captions: timing Timing example 1 Timing example 2

  33. Authoring captions: reviewing and exporting • Always review carefully • correct/edit/re-time as necessary • if a long video has been captioned by multiple authors, ensure that everyone has followed the same style rules • spelling, timing, editing, presentation conventions • Export to the appropriate target format

  34. Part IIb: How It’s Done/Caption Editors

  35. Various editors • Annotation Edit •  CapScribe Open • CPC • DIVX • Gnome Subtitles • Jubler •  MAGpie •  MovieCaptioner • Subtitle Workshop • vSync format converter • SubPLY, Subtitle Horse (on-line editors; export captions in various formats)

  36. (Cautiously) Using YouTube • YouTube can generate a complete caption file (transcribed and timed) for you (aka auto-caption) • upload video; wait for caption file to be generated • download caption file, clean up and re-upload • edit with a text editor • use a caption editor (required if re-timing is necessary) • demo: not bad but still requires clean-up and correction • You don’t have to do any clean-up, but… • In most cases, you must correct the auto-generated file

  37. Other YouTube options • Upload a plain-text transcript • YouTube will generate a timed script (movie) • download caption file; correct timing; re-upload • Upload your own complete caption file (movie) • in most cases, this is the most accurate option • TTML, SRT formats; others • File-creation guidelines for YouTube caption files

  38. Let others write captions for you • Professional captioning agency, such as the Media Access Group at WGBH • Crowdsourcing • free labor • loss of quality control • YouTube Subtitler • CaptionTube • Universal Subtitles • Overstream • dotSUB

  39. Part III: What’s Next?

  40. New rules • 21st Century Video Communications and Video Accessibility Act • programs that were originally captioned for broadcast must retain captions when distributed over IP • does not govern mobile television • FCC now considering final rules • distribution format for captions/subtitles under consideration (or not)

  41. Formats • Old way • each multimedia player/device used its own text-display format • New way • all players and devices use a single non-proprietary format (e.g., TTML) • The real way… • no single format will be used by all devices • FCC ruling on formats for IP distribution will have big impact • VPAAC working-group recommendation is SMPTE-TT

  42. Formats • Existing open formats • TTML • BBC, Netflix, Flash video, others • TTML community group at the W3C • SMPTE-TT • convert broadcast captions for IP delivery • UltraViolet • Coming soon • WebVTT (WHAT-WG) • WebVTT (W3C) • WebVTT (W3C community group) • Prediction • no agreement on a single contribution format • TTML, SMPTE-TT and WebVTT will be the primary contribution formats

  43. Viewing captions the new way: Web • HTML5 makes it much easier to embed video/audio into Web pages • <video>, <audio>; no plug-ins • <track> to identify and synchronize external caption/subtitle file(s) • currently no agreed-upon baseline format • (no agreed-upon video format, for that matter) • no public <track> support today, but soon • What it might look like

  44. Viewing captions the new way: mobile • Apple, BlackBerry devices • Mobile TV (OTA) • ATSC M/H (A/153) supports CC carriage • some LG and RCA receivers decode captions if available • receivers also available to build into cars/buses • watch television while traveling at speeds up to 120 mph • currently no regulations mandating ATSC M/H captions

  45. Resources List available at http://tinyurl.com/coa9ykk

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