| 摘要 |
<p>A method and apparatus for transmitting extended aspect ratio pictures is described. The transmitted pictures can be viewed on an extended aspect ratio high definition screen but can also be viewed on a reduced number of lines on a conventional receiver. The lines not used in the picture viewed on the conventional receiver contain non-visible data relating to picture information. The transmitter comprises a high definition television (HDTV) camera (42) providing a high definition video signal to a standards down-convertor (44). This has a video output with a reduced number of lines coupled to a frame store (46) and a data output connected to a buffer (48). Means (54) combines the data from the buffer (48) with the video signal from the frame store (46). A controller (50) responsive to synchronising information ensures that the data is combined with blank portions of the video signal. The combined signal is then fed to transmitter (53). At an HDTV receiver the front end circuitry (54) receives the video signal. A switch (56) under the control of a data/video detector (58) selects between sending video information to a frame store (60) and sending data to a standards up-convertor (64). The data is used to enhance picture information from the frame store (64), the resultant picture being displayed on an HDTV display.</p> |
