static public void DecodeAtomChildren(System.Action <TAtom> EnumAtom, TAtom Parent, System.Func <long, byte[]> ReadData = null)
{
long MoovPos = 0;
System.Func <long, byte[]> ReadMoovData = (long DataSize) =>
{
if (MoovPos == Parent.AtomData.Length)
{
return(null);
}
var ChildData = Parent.AtomData.SubArray(MoovPos, DataSize);
MoovPos += DataSize;
return(ChildData);
};
// decode moov children (mvhd, trak, udta)
int LoopSafety = 1000;
long FilePos = Parent.AtomDataFilePosition;
while (LoopSafety-- > 0)
{
// when this throws, we're assuming we're out of data
var NextAtom = GetNextAtom(ReadMoovData, FilePos);
if (!NextAtom.HasValue)
{
break;
}
var Atom = NextAtom.Value;
//Debug.Log("Found " + Atom.Fourcc);
EnumAtom(Atom);
FilePos += NextAtom.Value.AtomSize;
}
}
static public TAtom?GetChildAtom(TAtom ParentAtom, string Fourcc, System.Func <long, byte[]> ReadData)
{
TAtom?MatchAtom = null;
System.Action <TAtom> FindChild = (ChildAtom) =>
{
if (ChildAtom.Fourcc == Fourcc)
{
MatchAtom = ChildAtom;
}
};
DecodeAtomChildren(FindChild, ParentAtom);
return(MatchAtom);
}
public static TAtom?GetNextAtom(System.Func <long, byte[]> ReadData, long FilePosition)
{
byte[] AtomData = null;
try
{
AtomData = ReadData(TAtom.AtomHeaderSize);
// EOF
if (AtomData == null)
{
return(null);
}
}
catch (System.ArgumentException e)
{
Debug.Log("Ran out of atom data" + e);
return(null);
}
catch (System.Exception e)
{
Debug.Log("Ran out of atom data" + e);
// assuming out of data
return(null);
}
System.Func <byte[]> GetNext8 = () =>
{
var AtomExtData = ReadData(8);
return(AtomExtData);
};
// let it throw(TM)
var Atom = new TAtom();
Atom.FilePosition = FilePosition;
Atom.Init(AtomData, GetNext8);
// todo: can we verify the fourcc? lets check the spec if the characters have to be ascii or something
// grab the atom's data
if (Atom.DataSize > 0)
{
Atom.AtomData = ReadData(Atom.DataSize);
}
return(Atom);
}
static List <long> GetSampleSizes(TAtom Atom, byte[] FileData)
{
var Sizes = new List <long>();
var AtomData = Atom.AtomData;
// https://developer.apple.com/library/content/documentation/QuickTime/QTFF/QTFFChap2/qtff2.html
//var Version = AtomData[8];
/*var Flags = */ Get24(AtomData[9], AtomData[10], AtomData[11]);
var SampleSize = Get32(AtomData[12], AtomData[13], AtomData[14], AtomData[15]);
var EntryCount = Get32(AtomData[16], AtomData[17], AtomData[18], AtomData[19]);
// if size specified, they're all this size
if (SampleSize != 0)
{
for (int i = 0; i < EntryCount; i++)
{
Sizes.Add(SampleSize);
}
return(Sizes);
}
// each entry in the table is the size of a sample (and one chunk can have many samples)
var SampleSizeStart = 20;
// gr: docs don't say size, but this seems accurate...
SampleSize = (AtomData.Length - SampleSizeStart) / EntryCount;
for (int i = SampleSizeStart; i < AtomData.Length; i += SampleSize)
{
if (SampleSize == 3)
{
var Size = Get24(AtomData[i + 0], AtomData[i + 1], AtomData[i + 2]);
Sizes.Add(Size);
}
else if (SampleSize == 4)
{
var Size = Get32(AtomData[i + 0], AtomData[i + 1], AtomData[i + 2], AtomData[i + 3]);
Sizes.Add(Size);
}
}
if (Sizes.Count() != EntryCount)
{
Debug.LogWarning("Expected " + EntryCount + " sample sizes, got " + Sizes.Count());
}
return(Sizes);
}
static List <SampleMeta> GetSampleMetas(TAtom Atom, byte[] FileData)
{
var Metas = new List <SampleMeta>();
var AtomData = Atom.AtomData;
// https://developer.apple.com/library/content/documentation/QuickTime/QTFF/QTFFChap2/qtff2.html
//var Version = AtomData[8];
/*var Flags = */ Get24(AtomData[9], AtomData[10], AtomData[11]);
var EntryCount = Get32(AtomData[12], AtomData[13], AtomData[14], AtomData[15]);
var MetaSize = 3 * 4;
for (int i = 16; i < AtomData.Length; i += MetaSize)
{
var Meta = new SampleMeta(AtomData, i);
Metas.Add(Meta);
}
if (Metas.Count() != EntryCount)
{
Debug.LogWarning("Expected " + EntryCount + " sample metas, got " + Metas.Count());
}
return(Metas);
}
