Information transmitting apparatus and method, information receiving apparatus and method, information transmitting and receiving system and method, recording medium and program

Abstract

An original blanking period of a video signal is shortened to a set blanking period, and audio data is multiplexed into a resulting superimposing period. Table distinguishing data indicating the length of the superimposing period is inserted into the period as a blanking signal. With this configuration, it is possible to enable transmission and reception of an audio signal in a system capable of transmitting and receiving a video signal.

The invention claimed is: 
     
       1. A data transmission apparatus comprising
 a processor to implement:
 a first input unit for inputting video data of a predetermined number of bits; 
 a second input unit for inputting audio data; 
 a setting unit for setting, within a blanking period of the video data, a setup period that is shorter than the blanking period; 
 a multiplexing unit for multiplexing the audio data into a superimposing period, the superimposing period occurring within the blanking period and not including the setup period, and the setup period at least preceding the superimposing period; 
 a video data transmitting unit for encoding the video data to generate encoded video data having a number of bits greater than the predetermined number of bits and transmitting the encoded video data to a data channel; and 
 a retaining unit for retaining information on the setup period or the superimposing period, wherein the retaining unit retains a correspondence between a type of the video data and the setup period or superimposing period as the information on the setup period or superimposing period, and wherein the multiplexing unit multiplexes the audio data into the superimposing period on the basis of the information retained by the retaining unit, 
   the setup period being used to convey predetermined data other than video data or audio data; and   the predetermined data comprising information for identifying the encoded video data and the superimposing period.   
     
     
       2. A data transmission apparatus as claimed in  claim 1 , wherein the setting unit sets the setup period by disposing a blanking signal representing the blanking period only during the setup period and not during the superimposing period. 
     
     
       3. A data transmission apparatus as claimed in  claim 2 , wherein the blanking signal forms a control signal. 
     
     
       4. A data transmission apparatus as claimed in  claim 1 , further comprising a distinguishing information transmitter for transmitting distinguishing information for distinguishing the setup period or the superimposing period. 
     
     
       5. A data transmission apparatus as claimed in  claim 4 , wherein the distinguishing information transmitter transmits the distinguishing information in the setup period of the video data as a type of blanking signal representing a blanking period. 
     
     
       6. A data transmission apparatus as claimed in  claim 5 , wherein the distinguishing information transmitter transmits the distinguishing information its a vertical blanking period. 
     
     
       7. A data transmission apparatus as claimed in  claim 4 , wherein the distinguishing information transmitter transmits the distinguishing information via a transmission line different from a transmission line of the encoded video data. 
     
     
       8. A data transmission apparatus as claimed in  claim 4 , wherein the distinguishing information is information allowing determination of a period from a start point to an end point of the setup period or a period from a start point to an end point of the superimposing period. 
     
     
       9. A data transmission apparatus as claimed in  claim 1 , further comprising a compressing unit for compressing the audio data. 
     
     
       10. A data transmission apparatus as claimed in  claim 1 , further comprising an encrypting unit for encrypting the audio data by a method common with the video data. 
     
     
       11. An information receiving apparatus comprising
 a processor to implement:
 a receiver for receiving a transmitted signal; 
 a first capturing unit for capturing video data from the received signal; 
 a detecting unit for detecting a blanking period of the captured video data, the blanking period being set to a duration different from the duration of an original blanking period of the video data; 
 a second capturing unit for capturing information on a superimposing period of the received signal in which audio data is multiplexed, the superimposing period occurring within the original blanking period and not including the blanking period of the captured video data, and the blanking period of the captured video data at least preceding the superimposing period; 
 a third capturing unit for capturing the audio data from the received signal on the basis of the captured information and superimposing period; 
 a correcting unit for correcting the detected blanking period on the basis of the captured information on the superimposing period; and 
 a retaining unit for retaining the information on the superimposing period, wherein the retaining unit retains a correspondence between a type of the video data and the superimposing period as the information on the superimposing period, and wherein the second capturing unit captures the information on the superimposing period from the information retained by the retaining unit, 
 data indicative of the duration of the superimposing period being received during the blanking period of the captured video data. 
   
     
     
       12. An information receiving apparatus as claimed in  claim 11 , further comprising a converting unit for converting the audio data captured by the third capturing unit into a continuous signal. 
     
     
       13. An information receiving apparatus as claimed in  claim 11 , wherein a blanking signal representing the blanking period of the captured video data forms a control signal. 
     
     
       14. An information receiving apparatus as claimed in  claim 11 , further comprising a distinguishing information extracting unit for extracting distinguishing information for distinguishing the superimposing period. 
     
     
       15. An information receiving apparatus as claimed in  claim 14 , wherein the distinguishing information extracting unit extracts the distinguishing information from a blanking signal representing the blanking period of the captured video data, the blanking signal being inserted in the blanking period of the captured video data. 
     
     
       16. An information receiving apparatus as claimed in  claim 15 , wherein the distinguishing information extracting unit extracts the distinguishing information from the blanking signal in a vertical blanking period. 
     
     
       17. An information receiving apparatus as claimed in  claim 14 , wherein the distinguishing information extracting unit extracts the distinguishing information from in a signal received via a transmission line different from a transmission line of the captured video data. 
     
     
       18. An information receiving apparatus as claimed in  claim 14 , wherein the distinguishing information is information allowing determination of a period from a start point to an end point of the superimposing period or a period from a start point to an end point of the blanking period of the captured video data. 
     
     
       19. An information receiving apparatus as claimed in  claim 11 , wherein the audio data is compressed audio data, and
 further comprising an expanding unit for expanding the compressed audio data.   
     
     
       20. An information receiving apparatus as claimed in  claim 11 , further comprising a decrypting unit for decrypting the audio data by a method common with the video data, the audio data being encrypted by a method common with the video data. 
     
     
       21. An information processing apparatus, comprising:
 a storage unit; and   a transmitter that
 sets a first period in a blanking period, the duration of the first period being shorter than the duration of the blanking period; 
 multiplexes audio data into a second period corresponding to a difference between the blanking period and the first period; and 
 transmits an audio/video (AV) signal which includes video data, the audio data and distinguishing data for distinguishing the second period, 
   wherein the transmitter transmits the AV signal via transition minimized differential signaling (TMDS).   
     
     
       22. An information processing method, comprising:
 reading from a storage unit;   setting a first period in a blanking period, the duration of the first period being shorter than the duration of the blanking period;   multiplexing audio data into a second period corresponding to a difference between the blanking period and the first period; and   transmitting an audio/video (AV) signal which includes video data, the audio data and distinguishing data for distinguishing the second period,   wherein the step of transmitting comprises transmitting the AV signal via transition minimized differential signaling (TMDS).   
     
     
       23. A processor for an apparatus comprising a display and a speaker, the processor having a processing device that controls the apparatus to:
 read from a storage unit;   set a first period in a blanking period, the duration of the first period being shorter than the duration of the blanking period;   multiplex audio data into a second period corresponding to a difference between the blanking period and the first period; and   transmit an audio/video (AV) signal which includes video data, the audio data and distinguishing data for distinguishing the second period,   wherein the AV signal is transmitted via transition minimized differential signaling (TMDS).   
     
     
       24. An information processing apparatus comprising a display, a speaker and a processor, wherein the processor includes a processing device that controls the apparatus to:
 read from a storage unit;   set a first period in a blanking period, the duration of the first period being shorter than the duration of the blanking period;   multiplex audio data into a second period corresponding to a difference between the blanking period and the first period; and   transmit an audio/video (AV) signal which includes video data, the audio data and distinguishing data for distinguishing the second period,   wherein the A/V signal is transmitted via transition minimized differential signaling (TMDS).   
     
     
       25. An information processing apparatus, comprising:
 a receiver that
 receives a transmitted signal; 
 detects a first period in a blanking period, the duration of the first period being shorter than the duration of the blanking period; and 
 captures video data from the transmitted signal and audio data which is multiplexed into a second period corresponding to a difference between the blanking period and the first period; and 
   a digital-to-analog (D/A) converter that receives the audio data and converts the audio data,   wherein the receiver receives the transmitted signal via transition minimized differential signaling (TMDS).   
     
     
       26. An information processing method, comprising:
 receiving a transmitted signal;   detecting a first period in a blanking period, the duration of the first period being shorter than the duration of the blanking period;   capturing video data from the transmitted signal and audio data which is multiplexed into a second period corresponding to a difference between the blanking period and the first period;   receiving the audio data; and   performing D/A conversion on the audio data,   wherein the step of receiving comprises receiving the transmitted signal via transition minimized differential signaling (TMDS).   
     
     
       27. A processor for an apparatus, the processor having a processing device that controls the apparatus to:
 receive a transmitted signal;   detect a first period in a blanking period, the duration of the first period being shorter than the duration of the blanking period;   capture video data from the transmitted signal and audio data which is multiplexed into a second period corresponding to a difference between the blanking period and the first period; and   perform D/A conversion on the audio data,   wherein the transmitted signal is transmitted via transition minimized differential signaling (TMDS).   
     
     
       28. An information processing apparatus comprising a processor, wherein the processor includes a processing device that controls the apparatus to:
 receive a transmitted signal;   detect a first period in a blanking period, the duration of the first period being shorter than the duration of the blanking period;   capture video data from the transmitted signal and audio data which is multiplexed into a second period corresponding to a difference between the blanking period and the first period; and   perform D/A conversion on the audio data,   wherein the transmitted signal is transmitted via transition minimized differential signaling (TMDS).