Fast channel change via a mosaic channel
View Patent ↗A fast channel change (FFC) system including a tuner arrangement to receive at least one transport stream including an aggregated video service (AVS) and TV channels, each video frame of the AVS including some video data of each channel, a demultiplexer arrangement to demultiplex a first channel and the AVS, a FCC buffer to buffer the video frames of the AVS, a decoder arrangement to decode the first channel, a controller to instruct the decoder arrangement to switch from decoding the first channel to decoding the AVS from the FCC buffer, and a graphic engine to extract the video data of a second channel from the AVS yielding a full-screen video, and output the full-screen video to a display device, wherein the controller is operative to instruct the decoder arrangement to switch from decoding the AVS to decoding the second channel. Related apparatus and methods are also described.
1. A fast channel change system comprising:
a tuner arrangement to receive at least one transport stream including an aggregated video service and a plurality of TV channels, each of the TV channels including video data, the aggregated video service including a plurality of video frames, each of the video frames of the aggregated video service including some of the video data of each of the TV channels, the TV channels including a first TV channel and a second TV channel;
a demultiplexer arrangement to demultiplex the first TV channel and the aggregated video service from the at least one transport stream;
a fast channel change buffer to buffer the video frames of the aggregated video service, the aggregated video service including a plurality of random access points, the fast channel change buffer being operative to: buffer a latest one of the random access points and any of the video frames dependent upon the latest random access point for decoding purposes; and purge from the fast channel change buffer the video frames which are older than the latest random access point;
a decoder arrangement including at least one decoder and at least one decoder buffer, the decoder arrangement being operative to decode the video data of the first TV channel;
a controller to receive a channel change command from a subscriber to change channels from the first TV channel to the second TV channel, the controller being operative to instruct the decoder arrangement, on receipt of the channel change command, to switch from decoding the video data of the first TV channel to decoding the video frames of the aggregated video service from the fast channel change buffer yielding a plurality of decoded video frames; and
a graphic engine to: extract the video data of the second TV channel from the decoded video frames of the aggregated video service yielding a full-screen video of the extracted video data of the second TV channel; and output the full-screen video to a display device for display, wherein the controller is operative to: instruct the demultiplexer arrangement to demultiplex the second TV channel from the at least one transport stream; and instruct the decoder arrangement to switch from decoding the video frames of the aggregated video service to decoding the video data of the second TV channel.
2. The system according to claim 1 , wherein each of the video frames of the aggregated video services is formatted as a mosaic.
3. The system according to claim 1 , wherein the controller is operative to:
query the fast channel change buffer to ascertain a video frame X having the latest presentation time stamp of the video frames in the fast channel change buffer;
instruct the decoder arrangement to fast forward from the latest random access point in the fast channel change buffer to frame X+1 of the frames in the fast channel change buffer, the frame X+1 being the frame to be presented after frame X, wherein the frames in the fast channel change buffer until, but not including, frame X+1 are decoded, but are not outputted to the graphic engine; and
instruct the decoder arrangement to decode the frame X+1 and subsequent frames to frame X+1 at real-time speed and for output to the graphic engine.
4. The system according to claim 1 , further comprising a new channel buffer to buffer the video data of the second TV channel, wherein the controller is operative to instruct the decoder arrangement to switch from decoding the video frames of the aggregated video service to decoding the video data of the second TV channel from the new channel buffer.
5. The system according to claim 1 , wherein the video data of the second TV channel extracted from the decoded video frames of the aggregated video service is of a lower picture quality than the video data of the second TV channel which is not received as part of the aggregated video service.
6. The system according to claim 1 , wherein the graphic engine is operative to crop and enlarge the video data of the second TV channel extracted from the decoded video frames of the aggregated video service yielding the full-screen video.
7. The system according to claim 6 , wherein the graphic engine is operative to change the aspect ratio of the video data of the second TV channel extracted from the aggregated video service.
8. The system according to claim 1 , further comprising:
a security module to create a control word for decrypting the video frames of the aggregated video service if the subscriber is subscribed to any of the TV channels included in the aggregated video service; and
a decryption engine to decrypt the video frames of the aggregated video service based on the control word.
9. The system according to claim 8 , wherein the demultiplexer arrangement is operative to filter an entitlement control message which includes information for creating the control word.
10. The system according to claim 8 , wherein:
the controller is operative to send a query, upon receiving the channel change command from the subscriber to change channels from the first TV channel to the second TV channel, to the security module whether the subscriber has access to the second TV channel; and
the security module is operative to: check whether the subscriber has access; and send a suitable response to the controller.
11. A fast channel change method comprising:
receiving at least one transport stream including an aggregated video service and a plurality of TV channels, each of the TV channels including video data, the aggregated video service including a plurality of video frames, each of the video frames of the aggregated video service including some of the video data of each of the TV channels, the TV channels including a first TV channel and a second TV channel;
demultiplexing the first TV channel and the aggregated video service from the at least one transport stream;
buffering the video frames of the aggregated video service, the aggregated video service including a plurality of random access points; wherein the buffering includes buffering a latest one of the random access points and any of the video frames dependent upon the latest random access point for decoding purposes; and purging the video frames which are older than the latest random access point;
decoding the video data of the first TV channel;
receiving a channel change command from a subscriber to change channels from the first TV channel to the second TV channel; then
on receipt of the channel change command, switching from decoding the video data of the first TV channel to decoding the buffered video frames of the aggregated video service yielding a plurality of decoded video frames;
extracting the video data of the second TV channel from the decoded video frames of the aggregated video service yielding a full-screen video of the extracted video data of the second TV channel;
outputting the full-screen video to a display device for display;
demultiplexing the second TV channel from the at least one transport stream; and
switching from decoding the video frames of the aggregated video service to decoding the video data of the second TV channel.