/* * Copyright 2015, Mozilla Foundation and contributors * * Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include "AnnexB.h" #include "BigEndian.h" #include <cstring> using mozilla::BigEndian; static const uint8_t kAnnexBDelimiter[] = { 0, 0, 0, 1 }; /* static */ void AnnexB::ConvertFrameInPlace(std::vector<uint8_t>& aBuffer) { for (size_t i = 0; i < aBuffer.size() - 4 - sizeof(kAnnexBDelimiter) + 1; ) { uint32_t nalLen = BigEndian::readUint32(&aBuffer[i]); memcpy(&aBuffer[i], kAnnexBDelimiter, sizeof(kAnnexBDelimiter)); i += nalLen + 4; } } static void ConvertParamSetToAnnexB(std::vector<uint8_t>::const_iterator& aIter, size_t aCount, std::vector<uint8_t>& aOutAnnexB) { for (size_t i = 0; i < aCount; i++) { aOutAnnexB.insert(aOutAnnexB.end(), kAnnexBDelimiter, kAnnexBDelimiter + sizeof(kAnnexBDelimiter)); uint16_t len = BigEndian::readUint16(&*aIter); aIter += 2; aOutAnnexB.insert(aOutAnnexB.end(), aIter, aIter + len); aIter += len; } } /* static */ void AnnexB::ConvertConfig(const std::vector<uint8_t>& aBuffer, std::vector<uint8_t>& aOutAnnexB) { // Skip past irrelevant headers auto it = aBuffer.begin() + 5; if (it >= aBuffer.end()) { return; } size_t count = *(it++) & 31; // Check that we have enough bytes for the Annex B conversion // and the next size field. Bail if not. if (it + count * 2 >= aBuffer.end()) { return; } ConvertParamSetToAnnexB(it, count, aOutAnnexB); // Check that we have enough bytes for the Annex B conversion. count = *(it++); if (it + count * 2 > aBuffer.end()) { aOutAnnexB.clear(); return; } ConvertParamSetToAnnexB(it, count, aOutAnnexB); }