Saya mau tau DTV standard captioning improvements dari Penyarikataan tertutup. Jelaskan dalam bahasa melayu

The CEA-708 specification provides for dramatically improved captioning

An enhanced character set with more accented letters and non-Latin letters, and more special symbols

Viewer-adjustable text size (called the "caption volume control" in the specification), allowing individuals to adjust their TVs to display small, normal, or large captions

More text and background colors, including both transparent and translucent backgrounds to optionally replace the big black block

More text styles, including edged or drop-shadowed text rather than the letters on a solid background

More text fonts, including monospaced and proportional spaced, serif and sans-serif, and some playful cursive fonts

Higher bandwidth, to allow more data per minute of video

More language channels, to allow the encoding of more independent caption streams

As of 2009, however, most closed captioning for DTV environments is done using tools designed for analog captioning (working to the CEA-608 NTSC spec rather than the CEA-708 DTV spec). The captions are then run through transcoders made by companies like EEG Enterprises or Evertz, which convert the analog Line 21 caption format to the digital format. This means that none of the CEA-708 features are used unless they were also contained in CEA-608.

Non-linear video editing systems and penyarikataan tertutup

In April, 2010, Sony Creative Software released the Vegas Pro 9.0d update to the professional non-linear editor, Vegas Pro which implemented basic support for importing, editing, and delivering CEA608 Closed Captions. Vegas Pro 10, released on October 11, 2010, added several enhancements to the closed captioning support. TV-like CEA608 Closed Captioning can now be displayed as an overlay when played back in the Preview and Trimmer windows making it easy to check placement, edits, and timing of CC information. CEA708 style Closed Captioning is automatically created when the CEA608 data is created. Line 21 Closed Captioning is now supported as well as HD-SDI closed captioning capture and print from AJA and Blackmagic Design cards. Line 21 support provides a workflow for existing legacy media. Other improvements include increased support for multiple closed captioning file types, as well as the ability to export closed caption data for DVD Architect, YouTube, RealPlayer, QuickTime, and Windows Media Player.

In mid 2009, Apple released Final Cut Pro version 7 and began support for inserting closed caption data into SD and HD tape masters via firewire and compatible video capture cards.  Up until this time it was not possible for video editors to insert caption data with both CEA-608 and CEA-708 to their tape masters.  The typical workflow included first printing the SD or HD video to a tape and sending it to a professional closed caption service company that had a stand alone closed caption hardware encoder.

This new closed captioning workflow known as e-Captioning involves making a proxy video from the non-linear system to import into a third-party non-linear closed captioning software.  Once the closed captioning software project is completed, it must export a closed caption file compatible with the non-linear editing system.  In the case of Final Cut Pro 7, three different file formats can be accepted: a .SCC file (Scenarist Closed Caption file) for Standard Definition video, a QuickTime 608 Closed Caption track (a special 608 coded track in the .mov file wrapper) for Standard Definition video, and finally a QuickTime 708 Closed Caption track (a special 708 coded track in the .mov file wrapper) for High Definition video output.

Alternately, Matrox video systems devised another mechanism for inserting closed caption data by allowing the video editor to include CEA-608 and CEA-708 in a discrete audio channel on the video editing timeline.  This allows real-time preview of the captions while editing and is compatible with Final Cut Pro 6 and 7.

Other non-linear editing systems indirectly support closed captioning only in Standard Definition line-21.  Video files on the editing timeline must be composited with a line-21 VBI graphic layer known in the industry as a "blackmovie" with closed caption data.  Alternately, video editors working with the DV25 and DV50 firewire workflows must encode their DV .avi or .mov file with VAUX data which includes CEA-608 closed caption data.