Measuring and using reliability of complexity estimates during quality and rate control for digital audio
First Claim
1. In an audio encoder, a computer-implemented method comprising:
- encoding audio information, wherein the encoding includes;
computing a value of a control parameter for a block of spectral coefficients for the audio information, wherein the control parameter is based at least in part upon one or more complexity estimate noise measures, and wherein each of the one or more complexity estimate noise measures affects weight given to a corresponding complexity estimate in the computing the value of the control parameter; and
quantizing the block, wherein the value of the control parameter at least in part regulates the quantizing; and
outputting the encoded audio information as part of an encoded audio bitstream.
1 Assignment
0 Petitions
Accused Products
Abstract
An audio encoder regulates quality and bitrate with a control strategy. The strategy includes several features. First, an encoder regulates quantization using quality, minimum bit count, and maximum bit count parameters. Second, an encoder regulates quantization using a noise measure that indicates reliability of a complexity measure. Third, an encoder normalizes a control parameter value according to block size for a variable-size block. Fourth, an encoder uses a bit-count control loop de-linked from a quality control loop. Fifth, an encoder addresses non-monotonicity of quality measurement as a function of quantization level when selecting a quantization level. Sixth, an encoder uses particular interpolation rules to find a quantization level In a quality or bit-count control loop. Seventh, an encoder filters a control parameter value to smooth quality. Eighth, an encoder corrects model bias by adjusting a control parameter value in view of current buffer fullness.
125 Citations
28 Claims
-
1. In an audio encoder, a computer-implemented method comprising:
-
encoding audio information, wherein the encoding includes; computing a value of a control parameter for a block of spectral coefficients for the audio information, wherein the control parameter is based at least in part upon one or more complexity estimate noise measures, and wherein each of the one or more complexity estimate noise measures affects weight given to a corresponding complexity estimate in the computing the value of the control parameter; and quantizing the block, wherein the value of the control parameter at least in part regulates the quantizing; and outputting the encoded audio information as part of an encoded audio bitstream. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. An audio encoder comprising:
-
means for computing a value of a control parameter for audio information, wherein the control parameter is based at least in part upon one or more reliability measures for complexity estimates, and wherein each of the one or more reliability measures affects weight given to a corresponding one of the complexity estimates in the computing the value of the control parameter; and a quantizer for quantizing the audio information, wherein the value of the control parameter at least in part regulates the quantizer. - View Dependent Claims (9, 10, 11, 12)
-
-
13. A computer-readable storage medium storing computer-executable instructions for causing a computer system programmed thereby to perform a method comprising:
-
computing a value of a control parameter for a block of spectral audio information, wherein the control parameter is based at least in part upon one or more complexity estimate noise measures, and wherein each of the one or more complexity estimate noise measures affects weight given to a corresponding complexity estimate in the computing the value of the control parameter; and quantizing the block, wherein the value of the control parameter at least in part regulates the quantizing. - View Dependent Claims (14, 15, 16, 17, 18)
-
-
19. In an audio encoder, a computer-implemented method comprising:
-
encoding audio information, wherein the encoding includes; computing one or more complexity estimate noise measures, including computing a first measure of noise in a first complexity estimate, wherein the computing the one or more complexity estimate noise measures further includes lowpass filtering the first measure as part of a sequence; computing a value of a control parameter for a block of spectral coefficients for the audio information, wherein the control parameter is based at least in part upon the one or more complexity estimate noise measures; and quantizing the block, wherein the value of the control parameter at least in part regulates the quantizing; outputting the encoded audio information as part of an encoded audio bitstream. - View Dependent Claims (20, 21, 22, 23)
-
-
24. A computer-readable storage medium storing computer-executable instructions for causing a computer system programmed thereby to perform a method comprising:
-
computing one or more complexity estimate noise measures, including; computing a first measure of noise in a first complexity estimate, and lowpass filtering the first measure as part of a sequence; computing a value of a control parameter for a block of spectral audio information, wherein the control parameter is based at least in part upon the one or more complexity estimate noise measures; and quantizing the block, wherein the value of the control parameter at least in part regulates the quantizing. - View Dependent Claims (25, 26, 27, 28)
-
Specification