05148275 is referenced by 47 patents and cites 6 patents.

A television receiver having a video memory receives a small number of lines of a second low motion content video program transmitted during the vertical blanking interval of a first normal video program, stores and accumulates the lines of the second video program in video memory, and displays the image of the second video program when it is fully assembled. Audio for the second video program is conveyed via a second audio program (SAP) channel. In this manner two video programs, each of which is encoded in a standard television format (i.e., NTSC, PAL, or SECAM) can be received by a single tuner tuned to a single channel. In an embodiment utilizing picture-in-picture processing circuitry, the second video program can be displayed in an inset area of the screen.

Title
Second video program
Application Number
7/613033
Publication Number
5148275
Application Date
November 15, 1990
Publication Date
September 15, 1992
Inventor
Billy W Beyers Jr
Greenfield
IN, US
Harold Blatter
Indianapolis
IN, US
Agent
Thomas F Lenihan
Peter M Emanuel
Joseph S Tripoli
Assignee
Thomson Consumer Electronics
IN, US
IPC
H04N 5/272
H04N 5/262
H04N 7/04
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