Method and apparatus for providing low resolution images in a broadcast system

摘要

Low resolution information streams are combined in a broadcast carrier and broadcast along with full resolution information streams down a television broadcast network. The low resolution streams may be decoded and displayed in mosaic display with multiple images from separate low resolution streams simultaneously displayed. When a user selects a particular channel to be displayed, a low resolution stream associated with the selected channel is displayed (video and audio) while the full resolution stream is processed for display. Once the full resolution stream is available for display, it replaces the low resolution stream. The user perceives a much lower channel change time by viewing the low resolution stream during the channel change delay. The low resolution stream may also be provided directly to a portable media player (PMP) in a low resolution format required for display by the PMP.

主权项

1. An apparatus for broadcasting information from a headend or hub, the apparatus comprising:
an encoder which is configured to encode information streams to a plurality of full resolution encoded information streams; a modulator configured to modulate the plurality of full resolution encoded information streams for transmission over a plurality of broadcast carriers; a transcoder for transcoding the plurality of full resolution encoded information streams to a plurality of low resolution encoded information streams, such that each low resolution encoded information stream corresponds to a respective one of the plurality of full resolution encoded information streams, each low resolution stream having a lower bit rate than the corresponding full resolution encoded information stream, wherein the transmission of each low resolution stream is time aligned with the transmission of the corresponding full resolution encoded information stream; a combiner unit configured to aggregate the plurality of low resolution encoded information streams corresponding to the full resolution encoded information streams for modulating onto a single carrier; the modulator further configured to modulate the aggregated set of low resolution encoded information streams on the single carrier; a transmission unit for transmitting the modulated streams downstream from the headend or hub, wherein the full resolution encoded information streams are transmitted via the plurality of broadcast carriers and at least one full resolution encoded information stream is receivable by a first tuner at a user device for demodulating by a first demodulator and decoding by a first decoder, and wherein the aggregated low resolution encoded information streams that correspond to the full resolution encoded information streams are transmitted, in parallel to transmissions over the plurality of broadcast carriers, via the single carrier, the low resolution encoded information streams receivable by a second tuner at the user device for demodulating by a second demodulator and decoding by a second decoder, such that each of the aggregated low resolution encoded information streams are decoded in parallel to the at least one full resolution encoded information stream and is readily available for display, wherein the single carrier carrying the aggregated set of low resolution encoded information streams is distinct from a plurality of carriers carrying the corresponding full resolution encoded information streams.