Method and apparatus for receiving digital broadcasts

Abstract

In a digital broadcast receiving apparatus, digital broadcast signals provided by a digital broadcast method are supplied to various types of external units and are effectively utilized. In the above apparatus, a descrambler descrambles a transport stream output from a front end unit and supplies it to a digital interface and a demultiplexer. The demultiplexer extracts from the transport stream a compressed video signal and a compressed audio signal of a program specified by a user, and supplies the extracted signals to an MPEG decoder. The MPEG decoder decompresses the supplied video signal and the audio signal and supplies them to the digital interface, an NTSC encoder, and an audio signal D/A converter. The digital interface supplies either of the transport stream or the decompressed data to a digital external unit under the control of the controller.

What is claimed is:  
     
         1 . A digital broadcast receiving apparatus comprising: 
 broadcast program extraction means for extracting compressed data including a broadcast program selected and specified by a user;    decompression means for decompressing the compressed data extracted by said broadcast program extraction means and for outputting decompressed data; digital interface means for receiving-the compressed data extracted by said broadcast program extraction means and the decompressed data from said decompression means, and for outputting each of the compressed data and the decompressed data to a digital external unit; and    control means for controlling, based on an instruction from the user, the selection of an output of the compressed data extracted by said broadcast program extraction means or an output of the decompressed data from said decompression means to the digital external unit from said digital interface means.    
     
     
         2 . The digital broadcast receiving apparatus according to  claim 1 , wherein said broadcast program extraction means comprises a tuner for selecting a carrier component including the broadcast program selected and specified by the user, a front end unit for demodulating the carrier component selected by said tuner and for outputting a transport stream, and selected-program extraction means for extracting compressed data of the broadcast program selected and specified by the user from the transport stream output from said front end unit, and said broadcast program extraction means outputs the transport stream from said front end unit to said digital interface means and also outputs the compressed data of the broadcast program from said selected-program extraction means to said decompression means; 
 wherein said digital interface means receives the transport stream from said front end unit and decompressed data from said decompression means and outputs each of the transport stream and the decompressed data to the digital external unit; and    wherein said control means controls, based on an instruction from the user, the selection of an output of the transport stream or the decompressed data to the digital external unit from said digital interface means.    
     
     
         3 . The digital broadcast receiving apparatus according to  claim 1 , wherein the compressed data comprises data which is compressed by an MPEG method.  
     
     
         4 . A digital broadcast receiving apparatus for receiving a mixture of broadcast program signals provided as non-compressed data and broadcast program signals provided as compressed data, said apparatus comprising: 
 a tuner for selecting a carrier component including a signal of a broadcast program selected and specified by a user;    a front end unit for demodulating the carrier component selected by said tuner and for outputting a transport stream;    selected-program extraction means for extracting the non-compressed data or the compressed data of the broadcast program selected and specified by the user from the transport stream supplied from said front end unit;    digital interface means for receiving the transport stream from said front end unit and the non-compressed data extracted by said selected-program extraction means and for outputting each of the transport stream and the non-compressed data to a digital external unit; and    control means for controlling, based on an instruction from the user, the selection of an output of the transport stream or the non-compressed data to the digital external unit from said digital interface means.    
     
     
         5 . The digital broadcast receiving apparatus according to  claim 4 , further comprising decompression means for decompressing, in a case where the signal of the broadcast program extracted by said selected-program extraction means is compressed data, the compressed data, and for outputting decompressed data; 
 wherein said digital interface means receives the transport stream from said front end unit, the non-compressed data from said selected-program extraction means, and the decompressed data from said decompression means, and outputs each of the transport stream, the non-compressed data, and the decompressed data to the digital external unit; and    wherein said control means controls, based on an instruction from the user, the selection of an output of the transport stream, the non-compressed data, or the decompressed data from said digital interface means.    
     
     
         6 . The digital broadcast receiving apparatus according to  claim 4 , wherein the compressed data comprises data which is compressed by an MPEG method.  
     
     
         7 . The digital broadcast receiving apparatus according to  claim 4 , wherein the non-compressed data comprises digital data compressed by a method other than an MPEG method.  
     
     
         8 . A method of receiving a digital broadcast comprising the steps of: 
 (a) extracting a compressed data including a broadcast program selected and specified by a user;    (b) decompressing the compressed data extracted in said extracting step (a) and outputting decompressed data;    (c) outputting each of the compressed data extracted in said extracting step (a) and the decompressed data output from said decompressing step (b) to a digital external unit; and    (d) controlling, based on an instruction from the user, the selection of an output of the compressed data extracted in said extracting step (a) and the decompressed data output from said decompressing step (b) to the digital external unit from said-outputting step (c).    
     
     
         9 . The digital broadcast receiving method according to  claim 8 , wherein said extracting step (a) comprises the steps of: 
 (e) selecting a carrier component including a signal of the broadcast program selected and specified by the user;    (f) demodulating the carrier component selected in said selecting step (e) and outputting a transport stream;    (g) extracting the compressed data of the broadcast program selected and specified by the user from the transport stream output from said demodulating step (f), and said extracting step (a) outputs the transport stream from said demodulating step (f) to said outputting step (c), and also outputs the compressed data of the broadcast program from said selected-program extracting step (g);    wherein said outputting step (c) outputs each of the transport stream output from said demodulating step (f) and the decompressed data from said decompressing step (b) to a digital external unit; and    wherein said controlling step (d) controls, based on an instruction from the user, the selection of an output of the transport stream or the decompressed data from said outputting step (c) to the digital external unit.    
     
     
         10 . A method of receiving a digital broadcast, which is a mixture of broadcast program signals provided as non-compressed data and broadcast program signals provided as compressed data, comprising the steps of: 
 (h) selecting a carrier component including a signal of a broadcast program selected and specified by a user;    (i) demodulating the carrier component selected in said carrier component selecting step (h) and outputting a transport stream;    (j) extracting the non-compressed data or the compressed data of the broadcast program selected and specified by the user from the transport stream output from said demodulating step (i);    (k) receiving the transport stream from said demodulating step (i) and the non-compressed data extracted in said extracting step (j), and outputting each of the transport stream and the non-compressed data to a digital external unit; and    (l) controlling, based on an instruction from the user, the selection of an output of the transport stream or the non-compressed data from said receiving step (k) to the digital external unit.    
     
     
         11 . The digital broadcast program receiving method according to  claim 10 , further comprising the step of: 
 (m) decompressing a compressed data, in a case where the signal of the broadcast program extracted in said extracting step (j) is compressed data, and outputting decompressed data;    wherein said receiving step (k) outputs each of the transport stream from said demodulating step (i), the non-compressed data from said extracting step (j), and the decompressed data from said decompressing step (m) to the digital external unit; and    wherein said controlling step (l) controls, based on an instruction from the user, the selection of an output of the transport stream, the non-compressed data, or the decompressed data from said receiving step (k).