Communication processing system with multiple data layers for digital television broadcasting

A reception apparatus comprising:

• separating means that receives a signal that is generated by converting an image signal into a frequency domain signal by discrete cosine transform (DCT), dividing the frequency domain signal into m (m is an integer not less than 2) layers in terms of frequency to generate m layer signals, coding each of the layer signals, encrypting (m-1) layer signals obtained by the layer coding means excluding the lowest layer signal in a frequency domain and multiplexing the lowest layer signal and the (m-1) layer signals encrypted by the encrypting means, said separating means being used for separating the received signal into the lowest layer signal in the frequency domain and the encrypted (m-1) layer signals;
• decrypting means provided in correspondence to each of the encrypted (m-1) layer signals for decrypting an encrypted layer signal that is separated from the lowest layer signal by the separating means;
• layer decoding means provided in correspondence to each of the m layer signals for decoding each of the (m-1) layer signals decrypted by the corresponding decrypting means and the lowest layer signal separated by the separating means;
• and
• inverse discrete cosine transforming means for selecting layer signals corresponding in number to a designated resolution from among the lowest layer signal and the (m-1) layer signals in higher layers, all individually decoded by the corresponding layer decoding means, the layer signals being selected from the frequency domain in ascending order starting from the lowest layer signal, and said inverse discrete cosine transforming means being further used for combining the selected layer signals and inverse discrete cosine transforming a resultant signal to generate an image signal which realizes the designated resolution.

A communication processing system comprising:

• a transmission apparatus;
• and
• a reception apparatus,
• said transmission apparatus having:
• layer coding means for converting an image signal into a frequency domain signal by discrete cosine transform (DCT), dividing the frequency domain signal into m (m is an integer not less than 2) layers in terms of frequency to generate m layer signals, and coding each of the layer signals;
• encrypting means provided in correspondence to each of (m-1) layer signals of the layer signals obtained by the layer coding means in a frequency domain except for the lowest layer signal, for encrypting the (m-1) layer signals;
• and
• multiplexing means for multiplexing the lowest layer signal in the frequency domain and the (m-1) layer signals encrypted by the corresponding encrypting means and outputting a resultant signal as a transmission signal, and
• said reception apparatus having:
• separating means for receiving the transmission signal output from the transmission apparatus and separating the received signal into the lowest layer signal in the frequency domain and the encrypted (m-1) layer signals;
• decrypting means provided in correspondence to each of the encrypted (m-1) layer signals for decrypting an encrypted layer signal that is separated from the lowest layer signal by the separating means;
• layer decoding means provided in correspondence to each of the m layer signals for decoding each of the (m-1) layer signals decrypted by the corresponding decrypting means and the lowest layer signal separated by the separating means;
• and
• inverse discrete cosine transforming means for selecting layer signals corresponding in number to a designated resolution from among the lowest layer signal and the (m-1) layer signals in higher layers, all individually decoded by the corresponding layer decoding means, the layer signals being selected from the frequency domain in ascending order starting from the lowest layer signal, and said inverse discrete cosine transforming means being further used for combining the selected layer signals and inverse discrete cosine transforming a resultant signal to generate an image signal which realizes the designated resolution.

A transmission apparatus comprising:

• layer coding means for converting an image signal into a frequency domain signal by discrete cosine transform (DCT), dividing the frequency domain signal into m (m is an integer not less than 3) layers in terms of frequency to generate m layer signals, and coding each of the layer signals;
• encrypting means provided in correspondence to each of e (e is an integer not less than 2, m>e) of the layer signals obtained by the layer coding means for encrypting the e layer signals, the e layer signals being selected in descending order starting from the highest one in a frequency domain;
• and
• multiplexing means for multiplexing remaining (m-e) layer signals including the lowest ones that are coded by the layer coding means and the e layer signals encrypted by the corresponding encrypting means and outputting a resultant signal as a transmission signal.

A reception apparatus comprising:

• separating means that receives a signal that is generated by converting an image signal into a frequency domain signal by discrete cosine transform (DCT), dividing the frequency domain signal into m (m is an integer not less than 3) layers in terms of frequency to generate m layer signals, coding each of the layer signals, encrypting e (e is an integer not less than 2) of the layer signals obtained by the layer coding means, the e layer signals being selected from a frequency domain in descending order starting from the highest one, and multiplexing remaining (m-e) layer signals including the lowest one that are coded by the layer coding means and the e layer signals encrypted by the encrypting means, said separating means being used for separating the received signal into the e layer signals including the highest one that are encrypted and the remaining (m-e) layer signals including the lowest one in the frequency domain;
• decrypting means provided in correspondence to each of the encrypted e layer signals for decrypting an encrypted layer signal separated by the separating means;
• layer decoding means provided in correspondence to each of the m layer signals for decoding each of the e layer signals including the highest one that are decrypted by the corresponding decrypting means and the remaining (m-e) layer signals including the lowest one and separated by the separating means;
• and
• inverse discrete cosine transforming means for selecting layer signals corresponding in number to a designated resolution from among the e layer signals including the highest one and the remaining (m-e) layer signals including the lowest one, all individually decoded by the corresponding layer decoding means, the layer signals being selected from the frequency domain in an ascending order starting from the lowest one, and said inverse discrete cosine transforming means being further used for combining the selected layer signals and inverse discrete cosine transforming a resultant signal to generate an image signal which realizes the designated resolution.

A communication processing system comprising:

• a transmission apparatus;
• and
• a reception apparatus,
• said transmission apparatus having:
• layer coding means for converting an image signal into a frequency domain signal by discrete cosine transform (DCT), dividing the frequency domain signal into m (m is an integer not less than 3) layers in terms of frequency to generate m layer signals, and coding each of the layer signals;
• encrypting means provided in correspondence to each of e (e is an integer not less than 2, m>e) of the layer signals obtained by the layer coding means for encrypting the e layer signals, the e layer signals being selected in descending order starting from the highest one in a frequency domain;
• and
• multiplexing means for multiplexing remaining (m-e) layer signals including the lowest ones that are coded by the layer coding means and the e layer signals encrypted by the corresponding encrypting means and outputting a resultant signal as a transmission signal, and
• said receptions apparatus having:
• separating means for receiving the transmission signal from the transmission apparatus and separating the received signal into the e layer signals including the highest one that are encrypted and the remaining (m-e) layer signals including the lowest one in the frequency domain;
• decrypting means provided in correspondence to each of the encrypted e layer signals for decrypting an encrypted layer signal separated by the separating means;
• layer decoding means provided in correspondence to each of the m layer signals for decoding each of the e layer signals including the highest ones that are decrypted by the corresponding decrypting means and the remaining (m-e) layer signals including the lowest one and separated by the separating means;
• and
• inverse discrete cosine transforming means for selecting layer signals corresponding in number to a designated resolution from among the e layer signals including the highest one and the remaining (m-e) layer signals including the lowest one, all individually decoded by the corresponding layer decoding means, the layer signals being selected from the frequency domain in an ascending order starting from the lowest one, and said inverse discrete cosine transforming means being further used for combining the selected layer signals and inverse discrete cosine transforming a resultant signal to generate an image signal which realizes the designated resolution.

A transmission apparatus comprising:

• layer coding means for converting an image signal into a frequency domain signal by discrete cosine transform (DCT), dividing the frequency domain signal into m (m is an integer not less than 2) layers in terms of frequency to generate m layer signals, and coding each of the layer signals;
• secret level setting means provided in correspondence to each of the m layer signals generated by the layer coding means for generating an individual secret level setting signal;
• encrypting means provided in correspondence to each of the m layer signals generated by the layer coding means for encrypting an individual layer signal in accordance with a secret level that is determined by a corresponding secret level setting signal output from the corresponding secret level setting means;
• and
• multiplexing means for multiplexing the m layer signals each encrypted by the corresponding encrypting means and outputting a resultant signal as a transmission signal.

A reception apparatus comprising:

• separating means that receives a multiplexed signal that is generated by converting an image signal into a frequency domain signal by discrete cosine transform (DCT), dividing the frequency domain signal into m (m is an integer not less than 2) layers in terms of frequency to generate m layer signals, coding each of the layer signals, encrypting each of the layer signals obtained by the layer coding means in accordance with a secret level that is arbitrarily determined for each of the layer signals, and multiplexing the encrypted layer signals, said separating means being used for separating the received signal into the encrypted m layer signals;
• decrypting means provided in correspondence to each of the encrypted m layer signals for decrypting an individual encrypted layer signal that is separated, in accordance with the corresponding secret level;
• layer decoding means provided in correspondence to each of the m layer signals for decoding each of the m layer signals decrypted by the corresponding decrypting means;
• and
• inverse discrete cosine transforming means for selecting layer signals corresponding in number to a designated resolution from among the m layer signals, all individually decoded by the corresponding layer decoding means, the layer signals being selected from the frequency domain in ascending order starting from the lowest layer, and said inverse discrete cosine transforming means being further used for combining the selected layer signals and inverse discrete cosine transforming a resultant signal to generate an image signal which realizes the designated resolution.

A communication processing system comprising:

• a transmission apparatus;
• and
• a reception apparatus,
• said transmission apparatus having:
• layer coding means for converting an image signal into a frequency domain signal by discrete cosine transform (DCT), dividing the frequency domain signal into m (m is an integer not less than 2) layers in terms of frequency to generate m layer signals, and coding each of the layer signals;
• secret level setting means provided in correspondence to each of the m layer signals generated by the layer coding means for generating an individual secret level setting signal;
• encrypting means provided in correspondence to each of the m layer signals generated by the layer coding means for encrypting an individual layer signal in accordance with a secret level that is determined by a corresponding secret level setting signal output from the corresponding secret level setting means;
• and
• multiplexing means for multiplexing the m layer signals each encrypted by the corresponding encrypting means and outputting a resultant signal as a transmission signal, and
• said reception apparatus having:
• separating means for receiving the transmission signal and separating the received signal into the encrypted m layer signals;
• decrypting means provided in correspondence to each of the encrypted m layer signals for decrypting an individual encrypted layer signal that is separated, in accordance with the corresponding secret level;
• layer decoding means provided in correspondence to each of the m layer signals for decoding each of the m layer signals decrypted by the corresponding decrypting means;
• and
• inverse discrete cosine transforming means for selecting layer signals corresponding in number to a designated resolution from among the m layer signals, all individually decoded by the corresponding layer decoding means, the layer signals being selected from the frequency domain in ascending order starting from the lowest layer, and said inverse discrete cosine transforming means being further used for combining the selected layer signals and inverse discrete cosine transforming a resultant signal to generate an image signal which realizes the designated resolution.

A digital television broadcasting system in which a broadcast signal is transmitted and received, said broadcast signal being generated by converting a television signal into a frequency domain signal by discrete cosine transform (DCT), dividing the frequency domain signal into m (m is an integer not less than 2) layers in terms of frequency to generate m encoded signals, and multiplexing the coded signals,

• said digital television broadcasting system comprising:
• a transmission apparatus for transmitting said broadcast signal;
• and
• a plurality of unspecified reception apparatuses for each receiving said broadcast signal, wherein the transmission apparatus performs a scrambling process onto e (e is a natural number, m>e) encoded signals that are selected from the m encoded signals in descending order starting from the highest-frequency signal, and multiplexes the scrambled signals and remaining (m-e) encoded signals including the lowest-frequency signal into the broadcast signal, and
• each of the reception apparatuses extracts from the broadcast signal the e encoded signals including the highest-frequency signal and subjected to the scrambling process, performs a descrambling process onto the extracted signals, decodes the descrambled signals and the (m-e) remaining encoded signals including the lowest-frequency signal and unscrambled, combines decoded signals selected from among the decoded signals in ascending order starting from the lowest-frequency signal in the frequency domain in such a manner as to correspond in number to a designated resolution, and generates a television signal which realizes the designated resolution.

A reception apparatus used in a digital television broadcasting system in which a broadcast signal is transmitted and received, said broadcast signal being generated by converting a television signal into a frequency domain signal by discrete cosine transform (DCT), dividing the frequency domain signal into m (m is an integer not less than 2) layers in terms of frequency to generate m encoded signals, coding each of the encoded signals and multiplexing the coded signals, said broadcast signal being outputted from a transmission apparatus which performs a scrambling process onto e (e is a natural number, m>e) encoded signals selected from the m encoded signals in descending order starting from highest-frequency signal and codes and multiplexes the e encoded signals including the highest-frequency signal and subjected to the scrambling process and the remaining (m-e) encoded signals including the lowest-frequency signal to generate the broadcast signal,

• said reception apparatus comprising:
• separating means for separating the broadcast signal into the e encoded signals selected in descending order starting from the highest-frequency signal and subjected to the scrambling process and the remaining (m-e) encoded signals including the lowest-frequency signal and unscrambled;
• descrambling means for performing a descrambling process onto the e encoded signals separated by the separating means;
• decoding means for decoding each of the e encoded signals subjected to the descrambling process and the remaining (m-e) encoded signals;
• and
• television signal generating means for selecting decoded signals from among the m decoded signals in ascending order starting from the lowest-frequency signal in the frequency domain in such a manner as to correspond in number to a designated resolution, combining the selected signals and generating a television signal which realizes the designated resolution.

A transmission and reception method for a digital television broadcasting system in which a broadcast signal is transmitted and received, said broadcast signal being generated by converting a television signal into a frequency domain signal by discrete cosine transform (DCT), dividing the frequency domain signal into m (m is an integer not less than 2) layers in terms of frequency to generate m encoded signals, coding each of the encoded signals and multiplexing the coded signals, said transmission and reception method comprising:

• performing a scrambling process onto e (e is a natural number, m>e) of the encoded signals selected in descending order starting from the highest-frequency signal, and coding and multiplexing the e encoded signals including the highest-frequency signal and subjected to the scrambling process and the remaining (m-e) encoded signals including the lowest-frequency signal to generate the broadcast signal, on a transmission side;
• and
• extracting from the broadcast signal the e encoded signals including the highest-frequency signal and subjected to the scrambling process on the transmission side, performing a descrambling process onto the extracted signals, decoding the descrambled signals and the remaining (m-e) encoded signals including the lowest-frequency signal and unscrambled, combining decoded signals selected from among all the decoded signals in ascending order starting from the lowest-frequency signal in the frequency domain in such a manner as to correspond in number to a designated resolution, and generating a television signal which realizes the designated resolution.

A reception method for a digital television broadcasting system in which a broadcast signal is transmitted and received, said broadcast signal being generated by converting a television signal into a frequency domain signal by discrete cosine transform (DCT), dividing the frequency domain signal into m (m is an integer not less than 2) layers in terms of frequency to generate m encoded signals, coding each of the encoded signals and multiplexing the coded signals, wherein, on a transmission side, a scrambling process is performed onto e (e is a natural number, m>e) encoded signals selected from the m encoded signals in descending order starting from the highest-frequency signal, and the e encoded signals including the highest-frequency signal that are subjected to the scrambling process and the remaining (m-e) encoded signals including the lowest-frequency signal are coded and multiplexed to generate the broadcast signal,

• said reception method comprising:
• extracting from the broadcast signal the e encoded signals including the highest-frequency signal and subjected to the scrambling process on the transmission side, performing a descrambling process onto the extracted signals, decoding the descrambled signals and the remaining (m-e) encoded signals including the lowest-frequency signal and unscrambled signals, combining decoded signals selected from among all the decoded signals in ascending order starting from the lowest-frequency signal in the frequency domain, in such a manner as to correspond in number to a designated resolution and generating a television signal which realizes the designated resolution.