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authorDave Burke <daveburke@google.com>2012-04-17 09:51:45 -0700
committerDave Burke <daveburke@google.com>2012-04-17 23:04:43 -0700
commit9bf37cc9712506b2483650c82d3c41152337ef7e (patch)
tree77db44e2bae06e3d144b255628be2b7a55c581d3 /libSBRenc/src/env_bit.cpp
parenta37315fe10ee143d6d0b28c19d41a476a23e63ea (diff)
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Fraunhofer AAC codec.
License boilerplate update to follow. Change-Id: I2810460c11a58b6d148d84673cc031f3685e79b5
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-rw-r--r--libSBRenc/src/env_bit.cpp192
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diff --git a/libSBRenc/src/env_bit.cpp b/libSBRenc/src/env_bit.cpp
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+/****************************************************************************
+
+ (C) copyright Fraunhofer-IIS (2004)
+ All Rights Reserved
+
+ Please be advised that this software and/or program delivery is
+ Confidential Information of Fraunhofer and subject to and covered by the
+
+ Fraunhofer IIS Software Evaluation Agreement
+ between Google Inc. and Fraunhofer
+ effective and in full force since March 1, 2012.
+
+ You may use this software and/or program only under the terms and
+ conditions described in the above mentioned Fraunhofer IIS Software
+ Evaluation Agreement. Any other and/or further use requires a separate agreement.
+
+
+ This software and/or program is protected by copyright law and international
+ treaties. Any reproduction or distribution of this software and/or program,
+ or any portion of it, may result in severe civil and criminal penalties, and
+ will be prosecuted to the maximum extent possible under law.
+
+ $Id$
+
+*******************************************************************************/
+/*!
+ \file
+ \brief Remaining SBR Bit Writing Routines
+*/
+
+#include "env_bit.h"
+#include "cmondata.h"
+
+
+#ifndef min
+#define min(a,b) ( a < b ? a:b)
+#endif
+
+#ifndef max
+#define max(a,b) ( a > b ? a:b)
+#endif
+
+/* ***************************** crcAdvance **********************************/
+/**
+ * @fn
+ * @brief updates crc data register
+ * @return none
+ *
+ * This function updates the crc register
+ *
+ */
+static void crcAdvance(USHORT crcPoly,
+ USHORT crcMask,
+ USHORT *crc,
+ ULONG bValue,
+ INT bBits
+ )
+{
+ INT i;
+ USHORT flag;
+
+ for (i=bBits-1; i>=0; i--) {
+ flag = ((*crc) & crcMask) ? (1) : (0) ;
+ flag ^= (bValue & (1<<i)) ? (1) : (0) ;
+
+ (*crc)<<=1;
+ if(flag) (*crc) ^= crcPoly;
+ }
+}
+
+
+/* ***************************** FDKsbrEnc_InitSbrBitstream **********************************/
+/**
+ * @fn
+ * @brief Inittialisation of sbr bitstream, write of dummy header and CRC
+ * @return none
+ *
+ *
+ *
+ */
+
+INT FDKsbrEnc_InitSbrBitstream(HANDLE_COMMON_DATA hCmonData,
+ UCHAR *memoryBase, /*!< Pointer to bitstream buffer */
+ INT memorySize, /*!< Length of bitstream buffer in bytes */
+ HANDLE_FDK_CRCINFO hCrcInfo,
+ UINT sbrSyntaxFlags) /*!< SBR syntax flags */
+{
+ INT crcRegion = 0;
+
+ /* reset bit buffer */
+ FDKresetBitbuffer(&hCmonData->sbrBitbuf, BS_WRITER);
+
+ FDKinitBitStream(&hCmonData->tmpWriteBitbuf, memoryBase,
+ memorySize, 0, BS_WRITER);
+
+ if (sbrSyntaxFlags & SBR_SYNTAX_CRC) {
+ if (sbrSyntaxFlags & SBR_SYNTAX_DRM_CRC)
+ { /* Init and start CRC region */
+ FDKwriteBits (&hCmonData->sbrBitbuf, 0x0, SI_SBR_DRM_CRC_BITS);
+ FDKcrcInit( hCrcInfo, 0x001d, 0xFFFF, SI_SBR_DRM_CRC_BITS );
+ crcRegion = FDKcrcStartReg( hCrcInfo, &hCmonData->sbrBitbuf, 0 );
+ } else {
+ FDKwriteBits (&hCmonData->sbrBitbuf, 0x0, SI_SBR_CRC_BITS);
+ }
+ }
+
+ return (crcRegion);
+}
+
+
+/* ************************** FDKsbrEnc_AssembleSbrBitstream *******************************/
+/**
+ * @fn
+ * @brief Formats the SBR payload
+ * @return nothing
+ *
+ * Also the CRC will be calculated here.
+ *
+ */
+
+void
+FDKsbrEnc_AssembleSbrBitstream( HANDLE_COMMON_DATA hCmonData,
+ HANDLE_FDK_CRCINFO hCrcInfo,
+ INT crcRegion,
+ UINT sbrSyntaxFlags)
+{
+ USHORT crcReg = SBR_CRCINIT;
+ INT numCrcBits,i;
+
+ /* check if SBR is present */
+ if ( hCmonData==NULL )
+ return;
+
+ hCmonData->sbrFillBits = 0; /* Fill bits are written only for GA streams */
+
+ if ( sbrSyntaxFlags & SBR_SYNTAX_DRM_CRC )
+ {
+ /*
+ * Calculate and write DRM CRC
+ */
+ FDKcrcEndReg( hCrcInfo, &hCmonData->sbrBitbuf, crcRegion );
+ FDKwriteBits( &hCmonData->tmpWriteBitbuf, FDKcrcGetCRC(hCrcInfo)^0xFF, SI_SBR_DRM_CRC_BITS );
+ }
+ else
+ {
+ if ( !(sbrSyntaxFlags & SBR_SYNTAX_LOW_DELAY) )
+ {
+ /* Do alignment here, because its defined as part of the sbr_extension_data */
+ int sbrLoad = hCmonData->sbrHdrBits + hCmonData->sbrDataBits;
+
+ if ( sbrSyntaxFlags & SBR_SYNTAX_CRC ) {
+ sbrLoad += SI_SBR_CRC_BITS;
+ }
+
+ sbrLoad += 4; /* Do byte Align with 4 bit offset. ISO/IEC 14496-3:2005(E) page 39. */
+
+ hCmonData->sbrFillBits = (8 - (sbrLoad % 8)) % 8;
+
+ /*
+ append fill bits
+ */
+ FDKwriteBits(&hCmonData->sbrBitbuf, 0, hCmonData->sbrFillBits );
+
+ FDK_ASSERT(FDKgetValidBits(&hCmonData->sbrBitbuf) % 8 == 4);
+ }
+
+ /*
+ calculate crc
+ */
+ if ( sbrSyntaxFlags & SBR_SYNTAX_CRC ) {
+ FDK_BITSTREAM tmpCRCBuf = hCmonData->sbrBitbuf;
+ FDKresetBitbuffer( &tmpCRCBuf, BS_READER );
+
+ numCrcBits = hCmonData->sbrHdrBits + hCmonData->sbrDataBits + hCmonData->sbrFillBits;
+
+ for(i=0;i<numCrcBits;i++){
+ INT bit;
+ bit = FDKreadBits(&tmpCRCBuf,1);
+ crcAdvance(SBR_CRC_POLY,SBR_CRC_MASK,&crcReg,bit,1);
+ }
+ crcReg &= (SBR_CRC_RANGE);
+
+ /*
+ * Write CRC data.
+ */
+ FDKwriteBits (&hCmonData->tmpWriteBitbuf, crcReg, SI_SBR_CRC_BITS);
+ }
+ }
+
+ FDKsyncCache(&hCmonData->tmpWriteBitbuf);
+}
+