Broadcast system having transmission apparatus and receiving apparatus, the receiving apparatus, and program

A broadcast system including a transmission apparatus and a receiving apparatus, the transmission apparatus including:

• a generating unit operable to generate a first digital stream, a second digital stream, and a third digital stream by encoding a same signal respectively at different encoding bit rates, where an encoding bit rate for the first digital stream is the lowest among the encoding bits rates, an encoding bit rate for the second digital stream is the middle between encoding bit rates for the first and third digital streams, and an encoding bit rate for the third digital stream is the highest among the encoding bits rates;
• and
• a transmission unit operable to transmit the first, second, and third digital streams onto a transmission path while delaying the second digital stream by time period T1 and delaying the third digital stream by time period T2, wherein T2>T1,
• the receiving apparatus including:
• an accumulating unit operable to accumulate part of the first and second digital streams received from the transmission apparatus;
• are production unit operable to reproduce the third digital stream in a normal state;
• and
• a reproduction control unit operable to cause the reproduction unit to reproduce, instead of the third digital stream, the part of the second digital stream accumulated in the accumulating unit if a transmission path failure continues for the time period T2 or more, and to reproduce the part of the first digital stream accumulated in the accumulating unit following the reproduction of the part of the second digital stream accumulated in the accumulating unit.

A broadcast system including a transmission apparatus and a receiving apparatus, the transmission apparatus including:

• a first generating unit operable to generate a first audio stream and a second audio stream by encoding a same signal at different encoding bit rates, where an encoding bit rate for the first audio stream is lower than an encoding bit rate for the second audio stream;
• a second generating unit operable to generate a first video stream and a second video stream by encoding a same signal at different encoding bit rates, where an encoding bit rate for the first video stream is lower than an encoding bit rate for the second video stream;
• and
• a transmission unit operable to transmit the first and second audio streams and the first and second video streams onto a transmission path while delaying the second video stream by a time period T1 and delaying the second audio stream by a time period T2, wherein T2>T1,
• the receiving apparatus including:
• a first accumulating unit operable to accumulate part of the first video stream received during the time period T1 until a current time;
• a second accumulating unit operable to accumulate part of the first audio stream received during the time period T2 until the current time;
• a reproduction unit operable to reproduce the second video stream and the second audio stream in a normal state;
• and
• a reproduction control unit operable to cause the reproduction unit to reproduce (i) the part of the first video stream accumulated in the first accumulating unit and (ii) the part of the first audio stream accumulated in the second accumulating unit for the time period T1 if a transmission path failure continues for the time period T2 or more, and to reproduce, after the time period T1, the part of the first audio stream accumulated in the second accumulating unit.

A receiving apparatus for use in a broadcast system including a transmission apparatus that generates a first digital stream, a second digital stream, and a third digital stream by encoding a same signal respectively at different encoding bit rates, where an encoding bit rate for the first digital stream is the lowest among the encoding bits rates, an encoding bit rate for the second digital stream is the middle between encoding bit rates for the first and third digital streams, and an encoding bit rate for the third digital stream is the highest among the encoding bits rates, and transmits the first, second, and third digital streams onto a transmission path while delaying the second digital stream by time period T1 and delaying the third digital stream by time period T2, wherein T2>T1, the receiving apparatus comprising:

• an accumulating unit operable to accumulate part of the first and second digital streams received from the transmission apparatus;
• a reproduction unit operable to reproduce the third digital stream in a normal state;
• and
• a reproduction control unit operable to cause the reproduction unit to reproduce, instead of the third digital stream, the part of the second digital stream accumulated in the accumulating unit if a transmission path failure continues for the time period T2 or more, and to reproduce the part of the first digital stream accumulated in the accumulating unit following the reproduction of the part of the second digital stream accumulated in the accumulating unit.

A receiving apparatus for use in a broadcast system including a transmission apparatus that generates a first audio stream and a second audio stream by encoding a same signal at different encoding bit rates, where an encoding bit rate for the first audio stream is lower than an encoding bit rate for the second audio stream, generates a first video stream and a second video stream by encoding a same signal at different encoding bit rates, where an encoding bit rate for the first video stream is lower than an encoding bit rate for the second video stream, and transmits the first and second audio streams and the first and second video streams onto a transmission path while delaying the second video stream by a time period T1 and delaying the second audio stream by a time period T2, wherein T2>T1, the receiving apparatus comprising:

• a first accumulating unit operable to accumulate part of the first video stream received during the time period T1 until a current time;
• a second accumulating unit operable to accumulate part of the first audio stream received during the time period T2 until the current time;
• a reproduction unit operable to reproduce the second video stream and the second audio stream in a normal state;
• and
• a reproduction control unit operable to cause the reproduction unit to reproduce (i) the part of the first video stream accumulated in the first accumulating unit and (ii) the part of the first audio stream accumulated in the second accumulating unit for the time period T1 if a transmission path failure continues for the time period T2 or more, and to reproduce, after the time period T1, the part of the first audio stream accumulated in the second accumulating unit.

A program that causes a computer to execute a reception process in a broadcast system including a transmission apparatus that generates a first digital stream, a second digital stream, and a third digital stream by encoding a same signal respectively at different encoding bit rates, where an encoding bit rate for the first digital stream is the lowest among the encoding bits rates, an encoding bit rate for the second digital stream is the middle between encoding bit rates for the first and third digital streams, and an encoding bit rate for the third digital stream is the highest among the encoding bits rates, and transmits the first, second, and third digital streams onto a transmission path while delaying the second digital stream by time period T1 and delaying the third digital stream by time period T2, wherein T2>T1, the computer including

• an accumulating unit operable to accumulate part of the first and second digital streams received from the transmission apparatus,
• the reception process including:
• a reproduction step for reproducing the third digital stream in a normal state;
• and
• a reproduction control step for causing the reproduction step to reproduce, instead of the third digital stream, the part of the second digital stream accumulated in the accumulating unit if a transmission path failure continues for the time period T2 or more, and to reproduce the part of the first digital stream accumulated in the accumulating unit following the reproduction of the part of the second digital stream accumulated in the accumulating unit.

A program that causes a computer to execute a reception process in a broadcast system including a transmission apparatus that generates a first audio stream and a second audio stream by encoding a same signal at different encoding bit rates, where an encoding bit rate for the first audio stream is lower than an encoding bit rate for the second audio stream, generates a first video stream and a second video stream by encoding a same signal at different encoding bit rates, where an encoding bit rate for the first video stream is lower than an encoding bit rate for the second video stream, and transmits the first and second audio streams and the first and second video streams onto a transmission path while delaying the second video stream by a time period T1 and delaying the second audio stream by a time period T2, wherein T2>T1, the computer including:

• a first accumulating unit operable to accumulate part of the first video stream received during the time period T1 until a current time;
• and
• a second accumulating unit operable to accumulate part of the first audio stream received during the time period T2 until the current time,
• the reception process comprising:
• a reproduction step for reproducing the second video stream and the second audio stream in a normal state;
• and
• a reproduction control step for causing the reproduction step to reproduce (i) the part of the first video stream accumulated in the first accumulating unit and (ii) the part of the first audio stream accumulated in the second accumulating unit for the time period T1 if a transmission path failure continues for the time period T2 or more, and to reproduce, after the time period Ti, the part of the first audio stream accumulated in the second accumulating unit.