Circular buffer for processing audio samples

• US 6,044,434 A
• Filed: 09/24/1997
• Issued: 03/28/2000
• Est. Priority Date: 09/24/1997
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.), Sony Electronics Inc. (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.), Sony Electronics Inc. (Sony Group Corp.)
• Inventors: Oliver, Richard J.
• Primary Examiner(s): LANE, JOHN A
• Application Number:
  US08/937,140
• Time in Patent Office: 916 Days
• Field of Search: 711/110, 711/219, 700/94
• US Class Current: 711/110
• CPC Class Codes: G06F 5/10 having a sequence of storage locations each being individually accessible for both enqueue and dequeue operations, e.g. using random access memory G06F5/065 takes precedence

Abstract

A circular buffer in a system for processing audio samples wherein the buffer includes a sample window, the length of which is the length of a plurality of samples, the length of the circular buffer is a multiple of the length of the sample window, and the entire sample window is treated as a contiguous linear address space on each iteration of the processing system, that is moved through the physical multiple sample length buffer between iterations of the processing system, and is reset to the beginning every sample window number of iterations of the processing system. The circular buffer substantially reduces the number of address calculations in processing systems where every buffer position is addressed on every iteration and where circular addressing is not provided in hardware.

Claims

1. A system for processing audio samples, comprising:

a circular buffer for storing a plurality of the audio samples during iteration of the processing system, wherein a plurality of audio samples comprise an address, the length of the buffer comprises a multiple of the length of an address, the buffer includes first and second opposed ends, and an audio sample is added to multiple positions in the buffer upon each iteration of the processing system, the address moves through the buffer between iterations of the processing system, and an audio sample is removed from multiple positions in the buffer after a plurality of iterations of the processing system;

means for adding an audio sample to multiple positions in the buffer upon each iteration of the processing system;

means for moving the address through the buffer between iterations of the processing system; and

means for removing an audio sample from multiple positions in the buffer after each iteration of the processing system.

2. The buffer of claim 1, wherein the plurality of audio samples which comprise an address comprise N audio samples.

3. The buffer of claim 1, wherein the multiple positions comprise two positions.

4. The system of claim 1, further comprising means for controlling the motion of an audio transport responsive to an audio input from the motion of an audio source and an audio output to the audio transport derived from the audio input, wherein the motion of the audio source generates the audio samples for the circular buffer.

5. The buffer of claim 2, wherein the length of the buffer comprises 2N, and the multiple positions comprise two positions spaced N audio samples apart.

6. A method of processing audio samples, in a system for processing audio samples comprising a circular buffer for storing a plurality of the audio samples during iteration of the processing system, wherein a plurality of audio samples comprise an address, the length of the buffer comprises a multiple of the length of an address, the buffer includes first and second opposed ends, and an audio sample is added to multiple positions in the buffer upon each iteration of the processing system, the address moves through the buffer between iterations of the processing system, and an audio sample is removed from multiple positions in the buffer after each iteration of the processing system;

means for adding an audio sample to multiple positions in the buffer upon each iteration of the processing system, means for moving the address through the buffer between iterations of the processing system; and

means for removing an audio sample from multiple positions in the buffer after each iteration of the processing system, the method comprising the steps of;

activating an audio input to generate the audio samples;

activating the adding means to add an audio sample to multiple positions in the buffer upon each iteration of the processing system;

activating the moving means to move the address through the buffer between iterations of the processing system; and

activating the removing means to remove a sample from multiple positions in the buffer after each iteration of the processing system.

7. The method of claim 6, wherein the plurality of audio samples which comprise an address comprise N audio samples, the step of activating the adding means comprises adding audio samples to the buffer, and the step of activating the removing means comprise removing audio samples such that N audio samples are stored in the buffer.

8. The method of claim 7, wherein the length of the buffer comprises 2N, and the multiple positions comprise two positions spaced N audio samples apart, and the step of activating the adding means comprises adding each audio sample into the circular buffer at two positions spaced N audio samples apart.

9. The method of claim 6, wherein the multiple positions comprise two positions, and the steps of activating the adding means comprises adding audio samples at two positions.

10. The method of claim 6, wherein the system further comprises means for controlling the motion of an audio transport responsive to an audio input from the motion of an audio source and an audio output to the audio transport derived from the audio input, wherein the motion of the audio source generates the audio samples for the circular buffer, further comprising the steps of controlling the motion of the audio transport responsive to the audio input and audio output.