Line data    Source code

       1             : /******************************************************************************************************
       2             : 
       3             :    (C) 2022-2025 IVAS codec Public Collaboration with portions copyright Dolby International AB, Ericsson AB,
       4             :    Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V., Huawei Technologies Co. LTD.,
       5             :    Koninklijke Philips N.V., Nippon Telegraph and Telephone Corporation, Nokia Technologies Oy, Orange,
       6             :    Panasonic Holdings Corporation, Qualcomm Technologies, Inc., VoiceAge Corporation, and other
       7             :    contributors to this repository. All Rights Reserved.
       8             : 
       9             :    This software is protected by copyright law and by international treaties.
      10             :    The IVAS codec Public Collaboration consisting of Dolby International AB, Ericsson AB,
      11             :    Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V., Huawei Technologies Co. LTD.,
      12             :    Koninklijke Philips N.V., Nippon Telegraph and Telephone Corporation, Nokia Technologies Oy, Orange,
      13             :    Panasonic Holdings Corporation, Qualcomm Technologies, Inc., VoiceAge Corporation, and other
      14             :    contributors to this repository retain full ownership rights in their respective contributions in
      15             :    the software. This notice grants no license of any kind, including but not limited to patent
      16             :    license, nor is any license granted by implication, estoppel or otherwise.
      17             : 
      18             :    Contributors are required to enter into the IVAS codec Public Collaboration agreement before making
      19             :    contributions.
      20             : 
      21             :    This software is provided "AS IS", without any express or implied warranties. The software is in the
      22             :    development stage. It is intended exclusively for experts who have experience with such software and
      23             :    solely for the purpose of inspection. All implied warranties of non-infringement, merchantability
      24             :    and fitness for a particular purpose are hereby disclaimed and excluded.
      25             : 
      26             :    Any dispute, controversy or claim arising under or in relation to providing this software shall be
      27             :    submitted to and settled by the final, binding jurisdiction of the courts of Munich, Germany in
      28             :    accordance with the laws of the Federal Republic of Germany excluding its conflict of law rules and
      29             :    the United Nations Convention on Contracts on the International Sales of Goods.
      30             : 
      31             : *******************************************************************************************************/
      32             : 
      33             : /*====================================================================================
      34             :     EVS Codec 3GPP TS26.443 Nov 04, 2021. Version 12.14.0 / 13.10.0 / 14.6.0 / 15.4.0 / 16.3.0
      35             :   ====================================================================================*/
      36             : 
      37             : #include <stdint.h>
      38             : #include "options.h"
      39             : #include <math.h>
      40             : #include "prot.h"
      41             : #include "wmc_auto.h"
      42             : 
      43             : /*-------------------------------------------------------------------*
      44             :  * Correlation_shift
      45             :  *
      46             :  * Find normalized correlation correction dependent on estimated noise
      47             :  * Note: this variable is basically active only if noise suppression
      48             :  * is desactivated. * Otherwise, (for default NS = 14 dB and up to 10dB SNR)
      49             :  * it can be assumed about 0
      50             :  *-------------------------------------------------------------------*/
      51             : 
      52             : #define MAX_CORR_SHIFT 0.5f
      53             : 
      54             : /*! r: noise dependent voicing correction */
      55     1217770 : float correlation_shift(
      56             :     const float totalNoise /* i  : noise estimate over all critical bands */
      57             : )
      58             : {
      59             :     float corr_shift;
      60             : 
      61     1217770 :     corr_shift = 0.0f;
      62     1217770 :     if ( totalNoise > 28.18225893613955f ) /* to make corr_shift > 0.0 */
      63             :     {
      64             :         /* useful values range from 0 to 1 (can saturate at 1.0) */
      65      117101 :         corr_shift = 2.4492e-4f * (float) exp( 0.1596f * totalNoise ) - 0.022f;
      66             :     }
      67     1217770 :     if ( corr_shift > MAX_CORR_SHIFT )
      68             :     {
      69          18 :         corr_shift = MAX_CORR_SHIFT;
      70             :     }
      71     1217770 :     return corr_shift;
      72             : }