buffers.c

从FFMPEG转换而来的H264解码程序,VC下编译..

/* ***** BEGIN LICENSE BLOCK *****
 *
 * Portions Copyright (c) 1995-2005 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.
 *
 * 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 ***** */

/**************************************************************************************
 * Fixed-point HE-AAC decoder
 * Jon Recker ([e-mail])
 * February 2005
 *
 * buffers.c - allocation and deallocation of internal AAC decoder buffers
 **************************************************************************************/

#ifdef USE_DEFAULT_STDLIB
#include <stdlib.h>
#else
#include "hlxclib/stdlib.h"
#endif

#include "coder.h"

/**************************************************************************************
 * Function:    ClearBuffer
 *
 * Description: fill buffer with 0's
 *
 * Inputs:      pointer to buffer
 *              number of bytes to fill with 0
 *
 * Outputs:     cleared buffer
 *
 * Return:      none
 *
 * Notes:       slow, platform-independent equivalent to memset(buf, 0, nBytes)
 **************************************************************************************/
void ClearBuffer(void *buf, int nBytes)
{
	int i;
	unsigned char *cbuf = (unsigned char *)buf;

	for (i = 0; i < nBytes; i++)
		cbuf[i] = 0;

	return;
}

/**************************************************************************************
 * Function:    AllocateBuffers
 *
 * Description: allocate all the memory needed for the AAC decoder
 *
 * Inputs:      none
 *
 * Outputs:     none
 *
 * Return:      pointer to AACDecInfo structure, cleared to all 0's (except for
 *                pointer to platform-specific data structure)
 *
 * Notes:       if one or more mallocs fail, function frees any buffers already
 *                allocated before returning
 **************************************************************************************/
AACDecInfo *AllocateBuffers(void)
{
	AACDecInfo *aacDecInfo;

	aacDecInfo = (AACDecInfo *)malloc(sizeof(AACDecInfo));
	if (!aacDecInfo)
		return 0;
	ClearBuffer(aacDecInfo, sizeof(AACDecInfo));

	aacDecInfo->psInfoBase = malloc(sizeof(PSInfoBase));
	if (!aacDecInfo->psInfoBase) {
		FreeBuffers(aacDecInfo);
		return 0;
	}
	ClearBuffer(aacDecInfo->psInfoBase, sizeof(PSInfoBase));

	return aacDecInfo;
}

#ifndef SAFE_FREE
#define SAFE_FREE(x)	{if (x)	free(x);	(x) = 0;}	/* helper macro */
#endif

/**************************************************************************************
 * Function:    FreeBuffers
 *
 * Description: frees all the memory used by the AAC decoder
 *
 * Inputs:      pointer to initialized AACDecInfo structure
 *
 * Outputs:     none
 *
 * Return:      none
 *
 * Notes:       safe to call even if some buffers were not allocated (uses SAFE_FREE)
 **************************************************************************************/
void FreeBuffers(AACDecInfo *aacDecInfo)
{
	if (!aacDecInfo)
		return;

	SAFE_FREE(aacDecInfo->psInfoBase);
	SAFE_FREE(aacDecInfo);
}