ref: 3254623f0745837118e0d5d739fa6c402fd5b9d3
dir: /common/mp4av/mbs.cpp/
/* * The contents of this file are subject to the Mozilla Public * License Version 1.1 (the "License"); you may not use this file * except in compliance with the License. You may obtain a copy of * the License at http://www.mozilla.org/MPL/ * * Software distributed under the License is distributed on an "AS * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or * implied. See the License for the specific language governing * rights and limitations under the License. * * The Original Code is MPEG4IP. * * The Initial Developer of the Original Code is Cisco Systems Inc. * Portions created by Cisco Systems Inc. are * Copyright (C) Cisco Systems Inc. 2001-2002. All Rights Reserved. * * Contributor(s): * Dave Mackie [email protected] */ #include "mp4av_common.h" void CMemoryBitstream::AllocBytes(u_int32_t numBytes) { m_pBuf = (u_int8_t*)calloc(numBytes, 1); if (!m_pBuf) { throw ENOMEM; } m_bitPos = 0; m_numBits = numBytes << 3; } void CMemoryBitstream::SetBytes(u_int8_t* pBytes, u_int32_t numBytes) { m_pBuf = pBytes; m_bitPos = 0; m_numBits = numBytes << 3; } void CMemoryBitstream::PutBytes(u_int8_t* pBytes, u_int32_t numBytes) { u_int32_t numBits = numBytes << 3; if (numBits + m_bitPos > m_numBits) { throw EIO; } if ((m_bitPos & 7) == 0) { memcpy(&m_pBuf[m_bitPos >> 3], pBytes, numBytes); m_bitPos += numBits; } else { for (u_int32_t i = 0; i < numBytes; i++) { PutBits(pBytes[i], 8); } } } void CMemoryBitstream::PutBits(u_int32_t bits, u_int32_t numBits) { if (numBits + m_bitPos > m_numBits) { throw EIO; } if (numBits > 32) { throw EIO; } for (int8_t i = numBits - 1; i >= 0; i--) { m_pBuf[m_bitPos >> 3] |= ((bits >> i) & 1) << (7 - (m_bitPos & 7)); m_bitPos++; } } u_int32_t CMemoryBitstream::GetBits(u_int32_t numBits) { if (numBits + m_bitPos > m_numBits) { throw EIO; } if (numBits > 32) { throw EIO; } u_int32_t bits = 0; for (u_int8_t i = 0; i < numBits; i++) { bits <<= 1; bits |= (m_pBuf[m_bitPos >> 3] >> (7 - (m_bitPos & 7))) & 1; m_bitPos++; } return bits; }