Method for processing auxiliary information in a video system
View Patent ↗A method for processing auxiliary information, such as closed caption or teletext data, in a video system enables an increased number of characters to be displayed per line. According to an exemplary embodiment, a video system ( 100 ) includes a tuner ( 10 ) operative to receive a video signal including auxiliary information representative of a first number of characters to be displayed per line. A memory ( 13 ) is operative to store display list data representative of the received auxiliary information. A controller ( 11 ) is operative to retrieve the stored display list data in accordance with a format representative of a second number of characters per line, the second number being less than the first number.
1. A method for enabling display of auxiliary information included in a video signal, comprising steps of:
receiving the auxiliary information representative of a first number of characters to be displayed per line;
storing display list data representative of the received auxiliary information wherein the display list data representative of a first portion of the first number of characters and a pointer pointing to an address of a buffer is stored in a memory and the display list data representative of a second portion of the first number of characters is stored as bitmap data in the buffer;
retrieving the stored display list data representative of the first and second portions of the first number of characters using a controller; and
outputting pixel data to enable the display of the auxiliary information, wherein the display provides the first number of characters per line;
wherein:
the display list data for the first portion of the first number of characters is stored in a plurality of character tiles; and
the pointer is stored in a single character tile.
2. The method of claim 1 , wherein the auxiliary information comprises information representative of a real-time information component of the video signal.
3. The method of claim 1 , wherein:
the auxiliary information comprises closed caption data; and
the pointer points to bitmap data within the buffer for each character to be displayed.
4. The method of claim 1 , wherein:
the auxiliary information comprises closed caption data; and
the closed caption data is received in a vertical blanking interval portion of the video signal.
5. The method of claim 1 , wherein:
the auxiliary information comprises closed caption data; and
the closed caption data is received in one or more packets of digital data represented by the video signal.
6. The method of claim 1 , wherein:
the first number of characters comprises 34 characters; and
the second number of characters comprises 28 characters.
7. The method of claim 1 , wherein the plurality of character tiles and the single character tile are contiguous.
8. A video system, comprising:
a tuner operative to receive a video signal including auxiliary information representative of a first number of characters to be displayed per line;
a buffer;
a memory operative to store display list data representative of the received auxiliary information, wherein said memory stores the display list data representative of a first portion of the first number of characters and a pointer pointing to an address of said buffer and said buffer stores the display list data representative of a second portion of the first number of characters is stored as bitmap data, and
a controller operative to retrieve the stored display list data representative of the first and second portions of the first number of characters;
wherein:
the display list data for the first portion of the first number of characters is stored in a plurality of character tiles of the memory; and the pointer is stored in a single character tile of the memory.
9. The video system of claim 8 , wherein the controller is further operative to output pixel data to enable a display of the auxiliary information, wherein the display provides the first number of characters per line.
10. The video system of claim 8 , wherein the auxiliary information comprises information representative of a real-time information component of the video signal.
11. The video system of claim 8 , wherein:
the auxiliary information comprises closed caption data; and
pointer points to bitmap data for each character to be displayed.
12. The video system of claim 8 , wherein:
the auxiliary information comprises closed caption data; and
the closed caption data is received in a vertical blanking interval portion of the video signal.
13. The video system of claim 8 , wherein:
the auxiliary information comprises closed caption data; and
the closed caption data is received in one or more packets of digital data represented by the video signal.
14. The video system of claim 8 , wherein:
the first number of characters comprises 34 characters; and
the second number of characters comprises 28 characters.
15. The video system of claim 8 , wherein the plurality of character tiles and the single character tile are contiguous within the memory.