Method and apparatus for switching program streams using a fixed speed program stream buffer coupled to a decoder

A system, comprising:

• a media source;
• a program stream switching apparatus to couple to the media source, the program stream switching apparatus comprising:
• a display;
• a digital tuner module to decode multiple transport streams, the digital tuner module comprising a primary tuner to tune to an active channel, and one or more alternate tuners to tune to one or more alternate channels;
• a fixed speed program stream buffer coupled to a decoder to display media content on the display running at a normal cadence, the fixed speed program stream buffer to buffer historical frames comprising at least one anchor frame and to provide a most recent historical anchor frame prior to a detected channel switch point to the decoder, the fixed speed program stream buffer comprising an active channel program stream buffer to buffer historical frames of an active channel program stream corresponding to the active channel, one or more alternate channel programs stream buffers to buffer historical frames of one or more alternate channel program streams corresponding to the one or more alternate channels, and a start pointer that points to the most recent historical anchor frame, the decoder to stretch a next frame after the most recent historical anchor frame to synchronize to the normal cadence for display on the display, the active channel program stream buffer and the one or more alternate channel program stream buffers comprising elastic buffers to store a number of historical frames that varies over time.

A method, comprising:

• buffering historical frames of an active channel program stream, comprising at least one anchor frame of the active channel program stream, in an active channel program stream buffer coupled to a decoder to display media content on a display running at a normal cadence, the active channel program stream buffer comprising an elastic buffer, the active channel program stream corresponding to an active channel tuned by a primary tuner;
• buffering historical frames of one or more alternate channel program streams, comprising at least one anchor frame of the one or more alternate channel program streams, in one or more alternate channel program stream buffers coupled to the decoder, the one or more alternate channel program stream buffers comprising elastic buffers to store a number of historical frames that varies over time, the one or more alternate channel program streams corresponding to one or more alternate channels tuned by one or more alternate tuners;
• adjusting a start pointer to point to the most recent historical anchor frame;
• detecting a channel switch point;
• providing a most recent historical anchor frame prior to the channel switch point to the decoder using the start pointer;
• and
• stretching a next frame after the most recent historical anchor frame to synchronize to the normal cadence for display on the display.

An article comprising a non-transitory computer-readable storage medium containing instructions that if executed enable a system to:

• buffer historical frames of an active channel program stream, comprising at least one anchor frame of the active channel program stream, in an active channel program stream buffer coupled to a decoder to display media content on a display at a normal cadence, the active channel program stream buffer comprising an elastic buffer, the active channel program stream corresponding to an active channel tuned by a primary tuner;
• buffer historical frames of one or more alternate channel program streams, comprising at least one anchor frame of the one or more alternate channel program streams, in one or more alternate channel program stream buffers coupled to the decoder, the one or more alternate channel program stream buffers comprising elastic buffers to store a number of historical frames that varies over time, the one or more alternate channel program streams corresponding to one or more alternate channels tuned by one or more alternate tuners;
• adjust a start pointer to point to the most recent historical anchor frame;
• detect a channel switch point;
• provide a most recent historical anchor frame prior to the channel switch point to the decoder using the start pointer;
• and
• stretch a next frame after the most recent historical anchor frame to synchronize to the normal cadence for display on the display.