ref: 4041be70bf23c172dda3d107e19d84c2fb58f644
dir: /common/mp4v2/atom_stsc.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. All Rights Reserved. * * Contributor(s): * Dave Mackie [email protected] */ #include "mp4common.h" MP4StscAtom::MP4StscAtom() : MP4Atom("stsc") { AddVersionAndFlags(); MP4Integer32Property* pCount = new MP4Integer32Property("entryCount"); AddProperty(pCount); MP4TableProperty* pTable = new MP4TableProperty("entries", pCount); AddProperty(pTable); pTable->AddProperty( new MP4Integer32Property("firstChunk")); pTable->AddProperty( new MP4Integer32Property("samplesPerChunk")); pTable->AddProperty( new MP4Integer32Property("sampleDescriptionIndex")); // As an optimization we add an implicit property to this table, // "firstSample" that corresponds to the first sample of the firstChunk MP4Integer32Property* pSample = new MP4Integer32Property("firstSample"); pSample->SetImplicit(); pTable->AddProperty(pSample); } void MP4StscAtom::Read() { // Read as usual MP4Atom::Read(); // Compute the firstSample values for later use u_int32_t count = ((MP4Integer32Property*)m_pProperties[2])->GetValue(); MP4Integer32Property* pFirstChunk = (MP4Integer32Property*) ((MP4TableProperty*)m_pProperties[3])->GetProperty(0); MP4Integer32Property* pSamplesPerChunk = (MP4Integer32Property*) ((MP4TableProperty*)m_pProperties[3])->GetProperty(1); MP4Integer32Property* pFirstSample = (MP4Integer32Property*) ((MP4TableProperty*)m_pProperties[3])->GetProperty(3); MP4SampleId sampleId = 1; for (u_int32_t i = 0; i < count; i++) { pFirstSample->SetValue(sampleId, i); if (i < count - 1) { sampleId += (pFirstChunk->GetValue(i+1) - pFirstChunk->GetValue(i)) * pSamplesPerChunk->GetValue(i); } } }