MPD  0.20.15
noiseshape.h
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1 /*
2 
3 Copyright 2009, 2011 Sebastian Gesemann. All rights reserved.
4 
5 Redistribution and use in source and binary forms, with or without modification, are
6 permitted provided that the following conditions are met:
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8  1. Redistributions of source code must retain the above copyright notice, this list of
9  conditions and the following disclaimer.
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11  2. Redistributions in binary form must reproduce the above copyright notice, this list
12  of conditions and the following disclaimer in the documentation and/or other materials
13  provided with the distribution.
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15 THIS SOFTWARE IS PROVIDED BY SEBASTIAN GESEMANN ''AS IS'' AND ANY EXPRESS OR IMPLIED
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17 FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL SEBASTIAN GESEMANN OR
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25 The views and conclusions contained in the software and documentation are those of the
26 authors and should not be interpreted as representing official policies, either expressed
27 or implied, of Sebastian Gesemann.
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29  */
30 
31 #ifndef NOISE_SHAPE_H_INCLUDED
32 #define NOISE_SHAPE_H_INCLUDED
33 
34 #ifdef __cplusplus
35 extern "C" {
36 #endif
37 
38 typedef struct noise_shape_ctx_s {
39  int sos_count; /* number of second order sections */
40  const float *bbaa; /* filter coefficients, owned by user */
41  float *t1, *t2; /* filter state, owned by ns library */
43 
48 extern int noise_shape_init(
49  noise_shape_ctx *ctx,
50  int sos_count,
51  const float *coeffs);
52 
56 extern void noise_shape_destroy(
57  noise_shape_ctx *ctx);
58 
64 extern int noise_shape_clone(
65  const noise_shape_ctx *from, noise_shape_ctx *to);
66 
72 extern float noise_shape_get(
73  noise_shape_ctx *ctx);
74 
79 extern void noise_shape_update(
80  noise_shape_ctx *ctx, float qerror);
81 
82 #ifdef __cplusplus
83 } /* extern "C" */
84 #endif
85 
86 #endif /* NOISE_SHAPE_H_INCLUDED */
87 
int noise_shape_clone(const noise_shape_ctx *from, noise_shape_ctx *to)
initializes a noise_shaper context so that its state is a copy of a given context returns an error co...
int noise_shape_init(noise_shape_ctx *ctx, int sos_count, const float *coeffs)
initializes a noise_shaper context returns an error code or 0
const float * bbaa
Definition: noiseshape.h:40
float noise_shape_get(noise_shape_ctx *ctx)
computes the next "noise shaping sample".
void noise_shape_destroy(noise_shape_ctx *ctx)
destroys a noise_shaper context
struct noise_shape_ctx_s noise_shape_ctx
void noise_shape_update(noise_shape_ctx *ctx, float qerror)
updates the noise shaper's state with the last quantization error