limiter.h
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- /* ***** BEGIN LICENSE BLOCK *****
- * Source last modified: $Id: limiter.h,v 1.2.38.1 2004/07/09 02:00:38 hubbe Exp $
- *
- * Portions Copyright (c) 1995-2004 RealNetworks, Inc. All Rights Reserved.
- *
- * The contents of this file, and the files included with this file,
- * are subject to the current version of the RealNetworks Public
- * Source License (the "RPSL") available at
- * http://www.helixcommunity.org/content/rpsl unless you have licensed
- * the file under the current version of the RealNetworks Community
- * Source License (the "RCSL") available at
- * http://www.helixcommunity.org/content/rcsl, in which case the RCSL
- * will apply. You may also obtain the license terms directly from
- * RealNetworks. You may not use this file except in compliance with
- * the RPSL or, if you have a valid RCSL with RealNetworks applicable
- * to this file, the RCSL. Please see the applicable RPSL or RCSL for
- * the rights, obligations and limitations governing use of the
- * contents of the file.
- *
- * Alternatively, the contents of this file may be used under the
- * terms of the GNU General Public License Version 2 or later (the
- * "GPL") in which case the provisions of the GPL are applicable
- * instead of those above. If you wish to allow use of your version of
- * this file only under the terms of the GPL, and not to allow others
- * to use your version of this file under the terms of either the RPSL
- * or RCSL, indicate your decision by deleting the provisions above
- * and replace them with the notice and other provisions required by
- * the GPL. If you do not delete the provisions above, a recipient may
- * use your version of this file under the terms of any one of the
- * RPSL, the RCSL or the GPL.
- *
- * This file is part of the Helix DNA Technology. RealNetworks is the
- * developer of the Original Code and owns the copyrights in the
- * portions it created.
- *
- * This file, and the files included with this file, is distributed
- * and made available on an 'AS IS' basis, WITHOUT WARRANTY OF ANY
- * KIND, EITHER EXPRESS OR IMPLIED, AND REALNETWORKS HEREBY DISCLAIMS
- * ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES
- * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET
- * ENJOYMENT OR NON-INFRINGEMENT.
- *
- * Technology Compatibility Kit Test Suite(s) Location:
- * http://www.helixcommunity.org/content/tck
- *
- * Contributor(s):
- *
- * ***** END LICENSE BLOCK ***** */
- /* structure definitions and prototypes for audio limiter */
- #ifndef _LIMITER_H_
- #define _LIMITER_H_
- #ifdef __cplusplus
- extern "C" {
- #endif
- typedef struct LIMSTATE {
- /* settings */
- int samprate;
- int channels;
- int headroom;
- double dbgain;
- /* derived */
- unsigned int threshold;
- int reltc;
- int rmsatktc;
- int rmsreltc;
- int outfract;
- int outshift;
- /* state */
- int idx;
- int peak_z;
- int rms_z;
- int acc1;
- int acc2;
- unsigned int randsave;
- int delay[512];
- /* release tables */
- int peaktab[256];
- int rmstab[256];
- } LIMSTATE;
- LIMSTATE *LimiterInit(int samprate, int channels, int headroom);
- void LimiterFree(LIMSTATE *lim);
- void LimiterProcess(int *pcmbuf, int nsamples, LIMSTATE *lim);
- void LimiterOutput16(int *pcmbuf, short *outbuf, int nsamples, LIMSTATE *lim);
- void LimiterSetGain(double dbgain, LIMSTATE *lim);
- void LimiterSetRelease(double release, LIMSTATE *lim);
- /* delay in sample frames */
- int LimiterGetDelay(LIMSTATE *lim);
- double LimiterGetAtten(LIMSTATE *lim);
- #ifdef __cplusplus
- /*extern "C"*/ }
- #endif
- #endif /* _LIMITER_H_ */