Arrangement for decoding digital video signals
First Claim
1. A method of receiving a first video signal representing a main picture and a second video signal representing a picture-in-picture, the second video signal being encoded as an elementary stream including both autonomously encoded pictures and predictively encoded pictures, comprising the step of:
- receiving at a demultiplexer the first video signal and the second video signal; and
selecting and decoding only said autonomously encoded pictures for display as the picture-in-picture.
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Accused Products
Abstract
The invention relates to an arrangement for deriving an ancillary signal from a compressed digital video signal (e.g. MPEG). The ancillary signal comprises selected parts of the main signal, for example, the DC coefficients of I-pictures, or the unscrambled parts. The ancillary signal thus obtained can be used for display in a (multi-) picture-in-picture television receiver, or as an “appetizer” in order to encourage the user to pay a subscription fee. The ancillary signal can separately be recorded in digital video recorders so as to assist the user in finding the beginning of a scrambled program on tape. The ancillary signal can also be generated at the transmitter end and transmitted at a low bit rate. A decoder for decoding such an ancillary signal is considerably simpler and less expensive than a full-spec MPEG decoder.
113 Citations
20 Claims
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1. A method of receiving a first video signal representing a main picture and a second video signal representing a picture-in-picture, the second video signal being encoded as an elementary stream including both autonomously encoded pictures and predictively encoded pictures, comprising the step of:
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receiving at a demultiplexer the first video signal and the second video signal; and
selecting and decoding only said autonomously encoded pictures for display as the picture-in-picture. - View Dependent Claims (13, 14, 15, 20)
receiving in a demultiplexer a plurality of video signals encoded as elementary video streams, wherein each of said plurality of video signals includes both autonomously encoded pictures and predictively encoded pictures;
selecting only said autonomously encoded pictures in a multi-picture-in-picture decoder;
decoding said autonomously encoded pictures in said multi-picture-in-picture decoder; and
utilizing a control device to simultaneously display said plurality of pictures stored by said MPIP decoder as a mosaic picture.
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14. A method as set forth in claim 13 further comprising the steps of:
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selecting one of said displayed plurality of pictures;
decoding a video signal from said selected one of said displayed plurality of pictures; and
displaying said video signal.
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15. A method as set forth in claim 14 wherein said autonomously encoded pictures comprise transform-coded blocks having respective DC coefficients.
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20. A television receiver as set forth in claim 13 further including user control means for selecting one of the displayed plurality of pictures and adapted to select, decode, and display the video signal from which the selected picture has been derived.
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2. A television receiver comprising:
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a demultiplexer which receives a first video signal representing a main picture and a second video signal representing a picture-in-picture, the second video signal being encoded as an elementary stream including both autonomously encoded pictures and predictive encoded pictures; and
a picture-in-picture (PIP) decoder which selects and decodes only said autonomously encoded pictures for display as the picture-in-picture. - View Dependent Claims (3)
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4. A method of receiving a plurality of video signals encoded as elementary video streams each of which includes both autonomously encoded pictures and predictively encoded pictures, comprising the steps of:
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receiving at a demultiplexer the first video signal and the second video signal;
selecting and decoding said autonomously encoded pictures; and
simultaneously providing for display the respective plurality of pictures as a mosaic picture. - View Dependent Claims (16, 17, 18)
receiving in a demultiplexer a plurality of video signals encoded as elementary video streams, wherein each of said plurality of video signals includes both autonomously encoded pictures and predictively encoded pictures;
selecting only said autonomously encoded pictures in a multi-picture-in-picture decoder;
decoding said autonomously encoded pictures in said multi-picture-in-picture decoder; and
utilizing a control device to simultaneously display said plurality of pictures stored by said MPIP decoder as a mosaic picture.
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17. A method as set forth in claim 16 further comprising the steps of:
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selecting one of said displayed plurality of pictures;
decoding a video signal from said selected one of said displayed plurality of pictures; and
displaying said video signal.
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18. A method as set forth in claim 17 wherein said autonomously encoded pictures comprise transform-coded blocks having respective DC coefficients.
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5. A receiver comprising:
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a demultiplexer which receives a plurality of video signals encoded as elementary video streams, each including both autonomously encoded pictures and predictively encoded pictures;
a multi-picture-in-picture (MPIP) decoder which selects and decodes only said autonomously encoded pictures included in said plurality of video signals; and
a control device which simultaneously displays said selected and decoded said autonomously encoded pictures stored by said MPIP decoder as a mosaic picture;
wherein the autonomously encoded pictures comprise transform-coded blocks having respective DC coefficients and the MPIP decoder which selects and decodes the autonomously encoded pictures is adapted to select and decode only said DC coefficients. - View Dependent Claims (6)
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7. A television receiver comprising:
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means for demultiplexing a first video signal representing a main picture and a second video signal representing a picture-in-picture, the second video signal being encoded as an elementary stream including both autonomously encoded pictures and predictively encoded pictures; and
means for selecting and decoding only said autonomously encoded pictures for display as the picture-in-picture. - View Dependent Claims (8)
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9. A television receiver comprising:
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means for demultiplexing a plurality of video signals encoded as elementary video streams, each including both autonomously encoded pictures and predictively encoded pictures;
means for selecting and decoding only said autonomously encoded pictures; and
display means for simultaneously providing for display the respective plurality of pictures as a mosaic picture. - View Dependent Claims (10, 11)
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12. A television receiver comprising:
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a demultiplexer which receives a plurality of video signals encoded as elementary video streams, each including both autonomously encoded pictures and predictively encoded pictures;
a multi-picture-in-picture decoder which selects and decodes only said autonomously encoded pictures; and
a control device which simultaneously provides for display the respective plurality of pictures stored by said MPIP decoder as a mosaic picture. - View Dependent Claims (19)
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Specification