In January of 2012, The FCC released a Report and Order know as FCC-12-9 to extend rules and requirements for closed captioning to video programming delivered via Internet Protocol (IP). The report covers requirements for owners, providers, and distributors of IP-based video content, and provides an at-length discussion of how these rules were formulated and the scope to which they apply. To the set-top box manufacturer or application programmer, the additional requirements for closed caption display user configuration options are of interest. This white paper is a discussion of FCC-12-9 as it applies to the implementation of caption decoders, and how BitRouter’s CAPstack provides a solution to each of the issues raised.
The current version of FCC-12-9 can be found here »
FCC-12-9 is a report based on the Communications and Video Accessibility Act of 2010 (“CVAA”), describing updated rules and requirements for distribution and display of closed captioning in video programming delivered over IP. Much of the report is spent discussing rules for content providers and distributors, and is of little interest to manufacturers of video playback devices.
Section IV of FCC-12-9, discussion of Section 203 of the CVAA, gives the scope of the rules and regulations as they apply to end-user devices. The report defines an “apparatus” as to be covered by these rules, as a video player comprised of hardware, software, or a combination of hardware and software. This includes all consumer video playback devices such as smartphones, tablets, computers, set-top boxes, recording devices, and integrated software stacks. The rules apply to the device regardless of display size. From a consumer perspective, it is expected that a device with a video player should be capable of displaying closed captions.
Based on public comments received and discussed in Section 203 of the CVAA, a two-year implementation period has been adopted by the FCC for the rules detailed in the report. For hardware devices, the compliance deadline is January 1, 2014.
Caption Decoder Implementation Details
The rules for caption decoder devices are given in paragraph 111 of FCC-12-9 (discussion of Section 203 of the CVAA), and listed again in Appendix B – Final Rules, Section 10: Closed caption decoder requirements for all apparatus. The following is a list of these rules including a discussion of the impact to device manufacturers, and how BitRouter’s CAPstack provides a solution to the issue.
The device must support caption presentation in the styles defined by the CEA-708 and CEA-608 standards. The wording used in FCC-12-9 comes from CEA-608: text appearing all at once (pop-on), text that scrolls up as new text appears (roll-up), and text displayed character-by-character as it arrives (paint-on). This terminology isn’t used in CEA-708 but the caption presentation is the same. CAPstack inherently supports these presentation styles (and more). No user configuration options need to be added for this requirement.
FCC-12-9 requires the full 64 color palette defined by CEA-708 be supported. This applies to both the character foreground and background area. The device must further allow the user to override the stream-embedded colors to select a preferred color from a minimum set of eight: white, black, red, green, blue, yellow, magenta, and cyan. CAPstack supports the full 64-color palette and allows for user selection of any of these colors for character foreground and background.
The device must allow the user to select between three different opacity values for the character foreground and background; opaque, transparent, and translucent (semi-transparent). CAPstack allows each of these settings for character foreground and background. Note: FCC-12-9 does not clearly define what semi-transparent means. In paragraph 111, semi-transparent is defined as 75% or 25% opacity, whereas CEA-708 defines translucent as allowing the underlying video to pass through a fixed level of color background filtering so that underlying video may partially show through the window. CAPstack allows the default translucency value to be selected for optimal readability.
The device must allow the user to control size of the captioning text from 50% of the standard character size to 200%. CAPstack follows CEA-708’s recommended implementation for Small, Standard, and Large size settings and allows the user to select the preferred caption text size. Further, CAPstack also allows for precise control of the size and position of the screen area to which captions may be displayed.
FCC-12-9 requires the user to be given the ability to select between any of the eight font styles defined in CEA-708. CAPstack allows selection of a font style which will override the stream-embedded setting.
Character Edge Attributes.
CEA-708 defines five edge effects for characters, as well as no edge effect. The effects are Raised Edge, Depressed Edge, Uniform (outline), Left Drop Shadow, and Right Drop Shadow. Each of these must be displayed if embedded in the caption stream and user-selectable to override the stream default. CAPstack allows for user selection of edge effect. Note that FCC-12-9 makes no mention of user configuration of the edge effect color. It is our recommendation that configuration of edge effect color also be included the design of the device, as this may significantly assist with readability in some cases.
Caption Window Color.
FCC-12-9 requires the device be able to display the caption window color in any of the 64 colors defined by CEA-708, and in opaque, translucent, and transparent opacities. This requirement coincides with CEA-708. The rule in FCC-12-9, however, goes beyond CEA-708 and requires the device provide user configurability of caption window color and opacity, in the same manner as caption text color/opacity. CAPstack allows the user to explicitly override the stream-encoded caption window color and opacity settings using the same set of colors and opacities as for text foreground and background settings.
Note that allowing the user to override caption window opacity may give undesired results: a caption window as encoded may be much larger than the text enclosed within that window, with an embedded opacity of Transparent. This is not uncommon and looks normal when the caption window opacity is transparent. Allowing the user to set the window opacity to Solid will result in a large portion of the screen being obscured by the caption window. Also note these settings only apply to CEA-708-encoded captions; CEA-608 captions have no concept of a caption window.
Caption Service Selection.
FCC-12-9 requires the user be given a method in which to select between the available caption services. The various caption services may include additional languages or simplified captions. CAPstack allows the user to select between any possible service allowed by CEA-708 or CEA-608, and allows 708 and 608 service to be selected independently.
Easy Reader designation.
Each caption service may have metadata which describes the service, carried out of band from the caption service data elsewhere in the video stream transport. This metadata, commonly called the Caption Services Directory, includes items such as total number of available services, service type (CEA-608 or CEA-708), language, display aspect ratio, and Easy Reader flag. This out of band metadata is outside the scope of caption standards and outside of the scope of CAPstack.
Certain caption services may be formatted in a simplified manner in order to meet the needs of beginning readers. These services may be marked in the caption services directory metadata as “Easy Reader” services. Along with the ability to select between different caption services, FCC-12-9 requires a service marked as Easy Reader be identified in some way to the user. The method in which the caption service is designated as Easy Reader is not defined by FCC-12-9, but may include methods such as labeling the service with “Easy Reader” or “-ER” following the service name.
Caption Preview. FCC-12-9 requires a device to provide a preview of the caption text display based on the user selected settings. CAPstack includes an API which provides the application programmer a simple way to create a sample text string using a specific set of caption preferences. This sample text can be displayed and updated by the user interface as the user changes caption configuration options. When the changes are complete, the selected settings can be used as CAPstack’s preferences for caption rendering.
Any changes made by the user to the caption display configuration must be retained. This is assumed to mean a device will restore the user’s selections after a shutdown or reboot, and maintain those settings until the user changes them. While CAPstack doesn’t handle saving and restoring settings to non-volatile storage, it does provide a simple set of data to make saving and restoring configuration easy for the application programmer.
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