Methods and systems for encoding and decoding video data to enable random access and splicing

A method comprising:

• encoding multiple pictures of a picture sequence, individual pictures comprising I-, P- and B-pictures encoded using an encoding scheme characterized as follows:
• I-pictures are independently decodable;
• P-pictures can reference more than one different picture;
• P-pictures can reference future pictures in display time;
• B-pictures can reference more than two reference pictures;
• for any particular region of a B-picture, that region can reference one or more pictures and, if the region references more than one particular region, it can reference some mathematical combination of the pictures for that region;
• B-pictures can be used to predict a P-picture or another B-picture;
• and
• associating, in connection with said encoding, one or more random access points with the picture sequence, individual random access points comprising one or more of an entry point and a recovery point, individual entry and recovery points providing a measure of an amount of decoding that should take place to provide properly decoded pictures for display or other use.

A data sequence embodied on a computer-readable medium, the data sequence comprising:

• multiple encoded pictures of a picture sequence, individual pictures comprising I-, P- and B-pictures encoded using an encoding scheme characteristized as follows:
• I-pictures are independently decodable;
• P-pictures can reference more than one different picture;
• P-pictures can reference future pictures in display time;
• B-pictures can reference more than two reference pictures;
• for any particular region of a B-picture, that region can reference one or more pictures and, if the region references more than one particular region, it can reference some mathematical combination of the pictures for that region;
• B-pictures can be used to predict a P-picture or another B-picture;
• one or more random access points associated with the picture sequence, individual random access points comprising one or more of an entry point and a recovery point, individual entry and recovery points providing a measure of an amount of decoding that should take place to provide properly decoded pictures for display or other use.

A method comprising:

• receiving an encoded picture sequence comprising multiple pictures,
• receiving associated data that provides a measure that can be used to ascertain when decoding activities that start at some location in the picture sequence will result in properly decoded pictures;
• and
• using the data, decoding individual pictures of the picture sequence.

A method comprising:

• receiving an encoded picture sequence comprising multiple pictures,
• receiving associated data that provides a measure that can be used in a decoding process, said data comprising one or more sets of random access information, individual said sets of random access information comprising one or more of an entry point and a recovery point, individual entry and recovery points providing a measure of an amount of decoding that should take place to provide properly decoded pictures for display or other use;
• and
• using the data, decoding individual pictures of the picture sequence.

A method comprising:

• receiving an encoded picture sequence comprising multiple pictures, individual pictures comprising I-, P- and B-pictures encoded using an encoding scheme characterized as follows:
• I-pictures are independently decodable;
• P-pictures can reference more than one different picture;
• P-pictures can reference future pictures in display time;
• B-pictures can reference more than two reference pictures;
• for any particular region of a B-picture, that region can reference one or more pictures and, if the region references more than one particular region, it can reference some mathematical combination of the pictures for that region;
• B-pictures can be used to predict a P-picture or another B-picture;
• receiving associated data that provides a measure that can be used in a decoding process, said data comprising one or more sets of random access information, individual said sets of random access information comprising one or more of an entry point and a recovery point, individual entry and recovery points providing a measure of an amount of decoding that should take place to provide properly decoded pictures for display or other use;
• and
• using the data, decoding individual pictures of the picture sequence.

A method comprising:

• receiving an encoded picture sequence comprising multiple pictures,
• receiving associated data that provides a measure that can be used in a decoding process, said data comprising one or more sets of random access information, individual said sets comprising one or more of an entry point and a recovery point, individual entry and recovery points providing a measure of an amount of decoding that should take place to provide properly decoded pictures for display or other use;
• and
• using the data, decoding individual pictures of the picture sequence using a best efforts decoding process, the best efforts decoding process being characterized as one that attempts to decode all of the pictures regardless of whether the decoding process has access to a referenced picture and, in an event that the decoding process does not have access to a referenced picture or region thereof, generates the region to be decoded by initializing the inaccessible picture or region that is referenced or the current picture or region to be decoded to a predetermined or unspecified value.

A method comprising:

• receiving an encoded picture sequence comprising multiple pictures,
• receiving associated data that provides a measure that can be used in a decoding process, said data comprising one or more sets of random access information, individual said sets of random access information comprising one or more of an entry point and a recovery point, individual entry and recovery points providing a measure of an amount of decoding that should take place to provide properly decoded pictures for display or other use;
• and
• using the data, decoding individual pictures of the picture sequence using an assured decoding process, the assured decoding process being characterized as one that decodes only pictures or regions that the decoding process is clearly able to decode without reference to other pictures that are unavailable for use in the decoding process.