Detecting and processing multiplexed closed caption data
Methods, systems, and computer readable media can be operable to facilitate the detection of a closed caption standard and corresponding extraction of closed caption data according to the detected closed caption standard. A set-top box (STB) may receive content from multiple different networks and/or service providers, and closed caption data may be formatted differently in content received from the various networks and/or service providers. The STB may identify a relevant standard with which to process closed caption data in a received content stream based upon an identification of the network and/or provider from which the content stream is received, and the STB may extract and render closed caption data using a process associated with the identified network and/or provider.
1. A method comprising:
receiving a content stream carrying closed caption data, wherein the content stream is received at a set-top box that receives content from a cable network and a satellite network;
retrieving provider identification data from supplemental information data carried by the content stream;
if the provider identification data matches provider identification data associated with the cable network:
determining that the content stream is received from the cable network;
processing at least one user identification byte that follows the retrieved provider identification data;
identifying a closed caption indicator within the content stream at a position following the at least one user identification byte;
processing the identified closed caption indicator; and
extracting closed caption data from the content stream according to a closed caption extraction process associated with the cable network;
if the provider identification data does not match provider identification data associated with the cable network:
determining that the content stream is received from the satellite network;
foregoing a processing of one or more user identification bytes;
identifying a closed caption indicator within the content stream at a position immediately following the retrieved provider identification data;
processing the closed caption indicator; and
extracting closed caption data from the content stream according to a closed caption extraction process associated with the satellite network;
rendering the closed caption data for output to a display.
2. The method of claim 1 , wherein the provider identification data comprises a provider code within supplemental information data carried by the content stream.
3. The method of claim 1 , further comprising:
determining that the supplemental information data is invalid if the provider identification data does not match provider identification data associated with the cable network or the satellite network.
4. An apparatus comprising:
an input interface that receives one or more content streams from a cable network and a satellite network; and
one or more modules that:
retrieve provider identification data from supplemental information data carried by the content stream;
if the provider identification data matches provider identification data associated with the cable network:
determine that the content stream is received from the cable network;
process at least one user identification byte that follows the retrieved provider identification data;
identify a closed caption indicator within the content stream at a position following the at least one user identification byte;
process the identified closed caption indicator; and
extract closed caption data from the content stream according to a closed caption extraction process associated with the cable network;
if the provider identification data does not match provider identification data associated with the cable network:
determine that the content stream is received from the satellite network;
forego a processing of one or more user identification bytes;
identify a closed caption indicator within the content stream at a position immediately following the retrieved provider identification data;
process the closed caption indicator; and
extract closed caption data from the content stream according to a closed caption extraction process associated with the satellite network;
render the closed caption data for output to a display.
5. The apparatus of claim 4 , wherein the provider identification data comprises a provider code within supplemental information data carried by the content stream.
6. One or more non-transitory computer readable media having instructions operable to cause one or more processors to perform the operations comprising:
receiving a content stream carrying closed caption data, wherein the content stream is received at a set-top box that receives content from a cable network and a satellite network;
retrieving provider identification data from supplemental information data carried by the content stream;
if the provider identification data matches provider identification data associated with the cable network:
determining that the content stream is received from the cable network;
processing at least one user identification byte that follows the retrieved provider identification data;
identifying a closed caption indicator within the content stream at a position following the at least one user identification byte;
processing the identified closed caption indicator; and
extracting closed caption data from the content stream according to a closed caption extraction process associated with the cable network;
if the provider identification data does not match provider identification data associated with the cable network:
determining that the content stream is received from the satellite network;
foregoing a processing of one or more user identification bytes;
identifying a closed caption indicator within the content stream at a position immediately following the retrieved provider identification data;
processing the closed caption indicator; and
extracting closed caption data from the content stream according to a closed caption extraction process associated with the satellite network;
rendering the closed caption data for output to a display.
7. The one or more non-transitory computer-readable media of claim 6 , wherein the provider identification data comprises a provider code within supplemental information data carried by the content stream.
8. The one or more non-transitory computer-readable media of claim 6 , wherein the instructions are further operable to cause the one or more processors to perform the operations comprising:
determining that the supplemental information data is invalid if the provider identification data does not match provider identification data associated with the cable network or the satellite network.