Digital video/audio recording and reproducing apparatus

• US 5,878,183 A
• Filed: 06/06/1995
• Issued: 03/02/1999
• Est. Priority Date: 06/07/1991
• Status: Expired due to Term

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation), Mitsubishi Electric Corporation
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Hongo, Kimitoshi, Onishi, Ken, Sugiyama, Kazuhiro, Ono, Yukari
• Primary Examiner(s): TRAN, THAI Q
• Application Number:
  US08/466,281
• Time in Patent Office: 1,365 Days
• Field of Search: 386/39, 386/40, 386/33, 386/96-107, 386/109, 386/111, 386/112
• US Class Current: 386/323
• CPC Class Codes: G11B 20/00007 Time or data compression or expansion audio compression based on psychoacoustics G10L19/00; data processing for reproducing audio data at different playback speeds G10L21/04; video compression H04N19/00; data compression per se H03M7/30
• CPC Class Codes: H04N 19/124 Quantisation
• CPC Class Codes: H04N 19/146 Data rate or code amount at the encoder output
• CPC Class Codes: H04N 19/149 by estimating the code amount by means of a model, e.g. mathematical model or statistical model
• CPC Class Codes: H04N 19/152 by measuring the fullness of the transmission buffer
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• CPC Class Codes: H04N 19/60 using transform coding
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 19/88 involving rearrangement of data among different coding units, e.g. shuffling, interleaving, scrambling or permutation of pixel data or permutation of transform coefficient data among different blocks
• CPC Class Codes: H04N 5/78263 for recording on tracks inclined relative to the direction of movement of the tape
• CPC Class Codes: H04N 5/9264 using transform coding
• CPC Class Codes: H04N 5/9265 with processing of the sound signal
• CPC Class Codes: H04N 5/9268 with insertion of the PCM audio signals in the vertical blanking interval of the PCM video signal
• CPC Class Codes: H04N 5/945 for signals recorded by pulse code modulation

Abstract

A digital video/audio recording and reproducing apparatus comprising a video signal high-efficiency encoder having a variable reduction rate, an audio signal high-efficiency encoder having a variable reduction rate, and a controller for controlling the reduction rates in both of the high-efficiency encoders. The reduction rates in both of the high-efficiency encoders are controlled in such a manner that the sum of the information amount of the video signal and that of the audio signal, after high-efficiency encoding, is maintained constant. When recording multi-channel audio signals, the reduction rates in both of the high-efficiency encoders are controlled according to the number of audio signal channels to be recorded. The high frequency components of the high-efficiency encoded video and audio signals are recorded at the end portions of recording tracks on a magnetic tape, while the low frequency components thereof are recorded in the central portion of the recording tracks.

Claims

1. A digital video/audio reproducing apparatus for reproducing encoded signals obtained by encoding a digitized video signal and a digitized audio signal at a fixed amount of information per unit time to reproduce an original video signal and an original audio signal which were encoded by a video encoder and an audio encoder such that a sum of a varying information amount of the encoded digitized video signal and a varying information amount of the encoded digitized audio signal was maintained constant and such that the varying information amount of the encoded digitized video signal output from the video encoder was dependent on an output of the audio encoder.

2. The digital video/audio reproducing apparatus of claim 1, wherein the encoded digitized video signal and the encoded digitized audio signal are stored on one of the magnetic tape, magnetic disk, optical disk, and semiconductor memory.

3. A digital video/audio reproducing apparatus for reproducing encoded signals obtained by encoding a digitized video and a digitized audio signal at a fixed amount of information per unit time, said digital video/audio reproducing apparatus comprising:

first decoding means for expanding and decoding the encoded digitized video signal with a first variable expansion rate;

second decoding means for expanding and decoding the encoded digitized audio signal with a second variable expansion rate; and

control means for controlling the first and second expansion rates in said first and said second decoding means to reproduce an original video signal and an original audio signal which were encoded by a video encoder and an audio encoder so that a sum of a varying information amount of the encoded digitized video signal and a varying information amount of the encoded digitized audio signal was maintained constant and such that the varying information amount of the encoded digitized video signal output from the video encoder was dependent on an output of the audio encoder.

4. The digital video/audio reproducing apparatus of claim 3, wherein the encoded digitized video signal and the encoded digitized audio signal are stored on one of a magnetic tape, magnetic disk, optical disk, and semiconductor memory.

5. The digital video/audio reproducing apparatus of claim 3, wherein the encoded digitized video signal and the encoded digitized audio signal were recorded so that when the information amount of the encoded digitized video signal is smaller than a reserved video information amount, the encoded digitized audio signal is recorded in a recording area originally provided for recording the encoded digitized video signal, and so that when the information amount of the encoded digitized audio signal is smaller than a reserved audio information amount, the encoded digitized video signal is recorded in a recording area originally provided for recording the encoded digitized audio signal.

6. A digital video/audio reproducing apparatus for reproducing encoded signals obtained by encoding a digitized video signal and a digitized multi-channel audio signal at a fixed amount of information per unit time, said digital video/audio reproducing apparatus comprising:

decoding means for decoding the encoded digitized video signal with a variable expansion rate;

means for identifying a number of digitized audio signals to be reproduced from the digitized multi-channel audio signal; and

means for controlling the expansion rate in said decoding means according to the number of digitized audio signals to reproduce an original video signal and an original multi-channel audio signal which were encoded by a video encoder and an audio encoder so that a sum of a varying information amount of the encoded digitized video signal and a varying information amount of the number of digitized audio signals was maintained constant and such that the varying information amount of the encoded digitized video signal output from the video encoder was dependent on an output of the audio encoder.

7. The digital video/audio reproducing apparatus of claim 6, wherein the encoded digitized video signal and the number of digitized audio signals are stored on one of a magnetic tape, magnetic disk, optical disk, and semiconductor memory.

8. A digital video/audio reproducing apparatus for reproducing encoded signals obtained by encoding a digitized video signal and a digitized multi-channel audio signal at a fixed amount of information per unit time, said digital video/audio reproducing apparatus comprising:

first decoding means for expanding and decoding the encoded digitized video signal with a first variable expansion rate;

means for identifying a number of digitized audio signals to be reproduced from the encoded digitized multi-channel audio signal;

second decoding means for expanding and decoding the number of digitized audio signals with a second variable expansion rate; and

control means for controlling the first and second expansion rates in said first and said second decoding means to reproduce an original video signal and an original multi-channel audio signal which were encoded by a video encoder and an audio encoder so that a sum of a varying information amount of the encoded digitized video signal and a varying information amount of the number of digitized audio signals was maintained constant and such that the varying information amount of the encoded digitized video signal output from the video encoder was dependent on an output of the audio encoder.

9. The digital video/audio reproducing apparatus of claim 8, wherein the encoded digitized video signal and the number of digitized audio signals are stored on one of a magnetic tape, magnetic disk, optical disk, and semiconductor memory.

10. The digital video/audio reproducing apparatus of claim 8, wherein the encoded digitized video signal and the number of digitized audio signals were recorded so that reduction rates of the encoded digitized video signal and encoded digitized multi-channel audio signal increase when a number of audio signal channels selected for encoding increases, and decrease when the number of audio signal channels selected for encoding decreases, so that when the information amount of the encoded digitized video signal is smaller than a reserved video information amount, the number of the audio signals selected for encoding can be recorded in a recording area originally provided for recording the encoded digitized video signal and so that when the information amount of the number of audio signals selected for encoding is smaller than a reserved audio data amount, the encoded digitized video signals can be recorded in a recording area originally provided for recording the number of audio signals selected for recording.

11. A digital video/audio reproducing apparatus comprising:

first decoding means for expanding and decoding an encoded digitized video signal with a first expansion rate;

second decoding means for expanding and decoding an encoded digitized audio signal with a second expansion rate; and

control means for controlling the first and second expansion rates in said first and said second decoding means to reproduce an original video signal and an original audio signal which were encoded by a video encoder and an audio encoder so that a sum of a varying information amount of the encoded digitized video signal and a varying information amount of the encoded digitized audio signal was maintained constant and such that the varying information amount of the encoded digitized video signal output from the video encoder was dependent on an output of the audio encoder.

12. The digital video/audio reproducing apparatus of claim 11, wherein the encoded digitized video signal and the encoded audio signal are reproduced from one of a magnetic tape, magnetic disk, optical disk, and semiconductor memory.

13. The digital video/audio reproducing apparatus of claim 11, wherein the encoded digitized video signal and the encoded audio signal were recorded so that when the information amount of the encoded digitized video signal is smaller than a reserved video data amount, the encoded digitized audio signal is recorded in a recording area originally provided for recording the encoded digitized video signal, and so that when the information amount of the encoded digitized audio signal is smaller than a reserved audio data amount, the encoded digitized video signal is recorded in a recording area originally provided for recording the encoded digitized audio signal.

14. The digital video/audio reproducing apparatus of claim 11, wherein said second decoding means reproduces an original audio signal which was encoded such that the varying information amount of the encoded digitized audio signal output from the audio encoder is dependent on an output of the video encoder.

15. The digital video/audio reproducing apparatus of claim 11, wherein the varying information amount of the encoded digitized audio signal varies according to a character of the audio data.

16. The digital video/audio reproducing apparatus of claim 11, wherein the output of the audio encoder is a free amount of audio information.

17. The digital video/audio reproducing apparatus of claim 11, wherein the output of the audio encoder is a function of an estimated amount of audio information.

18. The digital video/audio reproducing apparatus of claim 11, wherein said control means limits a total combined data amount of the varying information amount of the encoded digitized audio signal and the varying information amount of the encoded digitized video signal to no more than a predetermined amount by controlling the video encoder to variably compress the varying information amount of the encoded digitized video signal, where the predetermined amount is less than a sum of a maximum audio capacity and a maximum video capacity.

19. The digital video/audio reproducing apparatus of claim 18, wherein the maximum audio capacity is less than the predetermined amount.

20. The digital video/audio reproducing apparatus of claim 18, wherein said control means limits the total combined data amount of the varying information amount of the encoded digitized audio signal and the varying information amount of the encoded digitized video signal to no more than the predetermined amount by also controlling the audio encoder to variably compress the varying information amount of the encoded digitized audio signal.

21. The digital video/audio reproducing apparatus of claim 11, wherein the varying information amount of the encoded digitized video signal varies according to a character of the video data.

22. A digital video/audio reproducing apparatus comprising:

decoding means for expanding and decoding an encoded digitized video signal with an expansion rate;

means for identifying a number of digitized audio signals to be reproduced from a multi-channel audio signal; and

means for controlling the expansion rate in said decoding means according to the number of digitized audio signals, to reproduce an original video signal and an original multi-channel audio signal which were encoded by a video encoder and an audio encoder so that a sum of a varying information amount of the encoded digitized video signal and a varying information amount of the number of digitized audio signals was maintained constant and such that the varying information amount of the encoded digitized video signal output from the video encoder was dependent on an output of the audio encoder.

23. The digital video/audio reproducing apparatus of claim 22, wherein the encoded digitized video signal and the number of digitized audio signals are stored on one of a magnetic tape, magnetic disk, optical disk, and semiconductor memory.

24. The digital video/audio reproducing apparatus of claim 22, wherein the varying information amount of the encoded digitized audio signal varies according to a number of supplied audio channels.

25. A digital video/audio reproducing apparatus comprising:

first decoding means for expanding and decoding an encoded digitized video signal with a first expansion rate;

means for identifying a number of digitized audio signals to be reproduced from a multi-channel audio signal;

second decoding means for expanding and decoding the number of audio signals with a second expansion rate; and

control means for controlling the first and second expansion rates in said first and said second decoding means to reproduce an original video signal and an original multi-channel audio signal which were encoded by a video encoder and an audio encoder so that a sum of a varying information amount of the encoded digitized video signal and a varying information amount of the number of digitized audio signals was maintained constant and such that the varying information amount of the encoded digitized video signal output from the video encoder was dependent on an output of the audio encoder.

26. The digital video/audio reproducing apparatus of claim 25, wherein the encoded digitized video signal and the number of audio digitized signals are stored on one of a magnetic tape, magnetic disk, optical disk, and semiconductor memory.

27. The digital video/audio reproducing apparatus of claim 25, wherein the encoded digitized video signal and the number of digitized audio signals were recorded so that reduction rates of the encoded digitized video signal and encoded digitized multi-channel audio signal increase when a number of digitized audio signal channels selected for recording increases, and decrease when the number of digitized audio signal channels selected for recording decreases, so that when the information amount of the encoded digitized video signal is smaller than a reserved video data amount, the number of the digitized audio signals selected for recording can be recorded in a recording area originally provided for recording the encoded digitized video signal and so that when the information amount of the number of digitized audio signals selected for recording is smaller than a reserved audio data amount, the encoded digitized video signal can be recorded in a recording area originally provided for recording the number of digitized audio signals selected for recording.

28. A method of reproducing encoded signals obtained by encoding a digitized video and a digitized audio signal at a fixed amount of information per unit time, said method comprising the steps of:

(a) expanding and decoding the encoded digitized video signal with a first variable expansion rate;

(b) expanding and decoding the encoded digitized audio signal with a second variable expansion rate; and

(c) controlling the first and second expansion rates in said steps (a) and (b) to reproduce an original video signal and an original audio signal which were encoded by a video encoder and an audio encoder so that a sum of a varying information amount of the encoded digitized video signal a varying information amount of the encoded digitized audio signal was maintained constant and such that the varying information amount of the encoded digitized video signal output from the video encoder was dependent on an output of the audio encoder.

29. The method of claim 28, wherein the encoded digitized video signal and the encoded digitized audio signal are stored on one of a magnetic tape, magnetic disk, optical disk, and semiconductor memory.

30. The method of claim 28, wherein the encoded digitized video signal and the encoded digitized audio signal were recorded so that when the information amount of the encoded digitized video signal is smaller than a reserved video information amount, the encoded digitized audio signal is recorded in a recording area originally provided for recording the encoded digitized video signal, and so that when the information amount of the encoder digitized audio signal is smaller than a reserved audio information amount, the encoded digitized video signal is recorded in a recording area originally provided for recording the encoded digitized audio signal.

31. A method of reproducing encoded signals obtained by encoding a digitized video signal and a digitized multi-channel audio signal at a fixed amount of information per unit time, said method comprising the steps of:

(a) decoding the encoded digitized video signal with a variable expansion rate;

(b) identifying a number of digitized audio signals to be reproduced from the digitized multi-channel audio signal; and

(c) controlling the expansion rate in said steps (a) and (b) according to the number of digitized audio signals to reproduce an original video signal and an original multi-channel audio signal which were encoded by a video encoder and an audio encoder so that a sum of a varying information amount of the encoded digitized video signal and a varying information amount of the number of digitized audio signals was maintained constant and such that the varying information amount of the encoded digitized video signal output from the video encoder was dependent on an output of the audio encoder.

32. The method according to claim 31, wherein the encoded digitized video signal and the number of digitized audio signals are stored on one of a magnetic tape, magnetic disk, optical disk, and semiconductor memory.

33. A method of reproducing encoded signals obtained by encoding a digitized video signal and a digitized multi-channel audio signal at a fixed amount of information per unit time, said method comprising the steps of:

(a) expanding and decoding the encoded digitized video signal with a first variable expansion rate;

(b) identifying a number of digitized audio signals to be reproduced from the encoded digitized multi-channel audio signal;

(c) expanding and decoding the number of digitized audio signals with a second variable expansion rate; and

(d) controlling the first and second expansion rates in said steps (a) and (c) to reproduce an original video signal and an original multi-channel audio signal which were encoded by a video encoder and an audio encoder so that a sum of a varying information amount of the encoded digitized video signal and a varying information amount of the number of digitized audio signals was maintained constant and such that the varying information amount of the encoded digitized video signal output from the video encoder was dependent on an output of the audio encoder.

34. The method of claim 33, wherein the encoded digitized video signal and the number of digitized audio signals are stored on one of a magnetic tape, magnetic disk, optical disk, and semiconductor memory.

35. The method of claim 33, wherein the encoded digitized video signal and the number of digitized audio signals were recorded so that reduction rates of the encoded digitized video signal and encoded digitized multi-channel audio signal increase when a number of audio signal channels selected for encoding increases, and decrease when the number of audio signal channels selected for encoding decreases, so that when the information amount of the encoded digitized video signal is smaller than a reserved video information amount, the number of the audio signals selected for encoding can be recorded in a recording area originally provided for recording the encoded digitized video signal and so that when the information amount of the number of audio signals selected for encoding is smaller than a reserved audio data amount, the encoded digitized video signals can be recorded in a recording area originally provided for recording the number of audio signals selected for recording.

36. A method comprising the steps of:

(a) expanding and decoding an encoded digitized video signal with a first expansion rate;

(b) expanding and decoding an encoded digitized audio signal with a second expansion rate; and

(c) controlling the first and second expansion rates in said steps (a) and (b) to reproduce an original video signal and an original audio signal which were encoded by a video encoder and an audio encoder so that a sum of a varying information amount of the encoded digitized video signal a varying information amount of the encoded digitized audio signal was maintained constant and such that the varying information amount of the encoded digitized video signal output from the video encoder was dependent on an output of the audio encoder.

37. The method of claim 36, wherein the encoded digitized video signal and the encoded audio signal are reproduced from one of a magnetic tape, magnetic disk, optical disk, and semiconductor memory.

38. The method of claim 36, wherein the encoded digitized video signal and the encoded digitized audio signal were recorded so that when the information amount of the encoded digitized video signal is smaller than a reserved video data amount, the encoded digitized audio signal is recorded in a recording area originally provided for recording the encoded digitized video signal, and so that when the information amount of the encoded digitized audio signal is smaller than a reserved audio data amount, the encoded digitized video signal is recorded in a recording area originally provided for recording the encoded digitized audio signal.

39. A method comprising the steps of:

(a) expanding and decoding an encoded digitized video signal with an expansion rate;

(b) identifying a number of digitized audio signals to be reproduced from a multi-channel audio signal; and

(c) controlling the expansion rate in said step (a) according to the number of digitized audio signals, to reproduce an original video signal and an original multi-channel audio signal which were encoded by a video encoder and an audio encoder so that a sum of a varying information amount of the encoded digitized video signal and a varying information amount of the number of digitized audio signals was maintained constant and such that the varying information amount of the encoded digitized video signal output from the video encoder was dependent on an output of the audio encoder.

40. The method of claim 39, wherein the encoded digitized video signal and the number of digitized audio signals are stored on one of a magnetic tape, magnetic disk, optical disk, and semiconductor memory.

41. A method comprising the steps of:

(a) expanding and decoding an encoded digitized video signal with a first expansion rate;

(b) identifying a number of digitized audio signals to be reproduced from a multi-channel audio signal;

(c) expanding and decoding the number of audio signals with a second expansion rate; and

(d) controlling the first and second expansion rates in said steps (a) and (c) to reproduce an original video signal and an original multi-channel audio signal which were encoded by a video encoder and an audio encoder so that a sum of a varying information amount of the encoded digitized video signal a varying information amount of the number of digitized audio signals was maintained constant and such that the varying information amount of the encoded digitized video signal output from the video encoder was dependent on an output of the audio encoder.

42. The method of claim 41, wherein the encoded digitized video signal and the encoded audio signal are reproduced from one of a magnetic tape, magnetic disk, optical disk, and semiconductor memory.

43. The method of claim 41, wherein the encoded digitized video signal and the encoded digitized audio signal were recorded so that when the information amount of the encoded digitized video signal is smaller than a reserved video data amount, the encoded digitized audio signal is recorded in a recording area originally provided for recording the encoded digitized video signal, and so that when the information amount of the encoded digitized audio signal is smaller than a reserved audio data amount, the encoded digitized video signal is recorded in a recording area originally provided for recording the encoded digitized audio signal.