public EXRPart(EXRVersion version, EXRHeader header, OffsetTable offsets)
{
Version = version;
Header = header;
Offsets = offsets;
if (Version.IsMultiPart)
{
Type = header.Type;
}
else
{
Type = version.IsSinglePartTiled ? PartType.Tiled : PartType.ScanLine;
}
DataWindow = Header.DataWindow;
FloatChannels = new Dictionary <string, float[]>();
HalfChannels = new Dictionary <string, Half[]>();
foreach (var channel in header.Channels)
{
if (channel.Type == PixelType.Float)
{
FloatChannels[channel.Name] = new float[DataWindow.Width * DataWindow.Height];
}
else if (channel.Type == PixelType.Half)
{
HalfChannels[channel.Name] = new Half[DataWindow.Width * DataWindow.Height];
}
else
{
throw new NotImplementedException("Only 16 and 32 bit floating point EXR images are supported.");
}
}
}
public void Read(IEXRReader reader)
{
// first four bytes of an OpenEXR file are always 0x76, 0x2f, 0x31 and 0x01 or 20000630
var magicNumber = reader.ReadInt32();
if (magicNumber != 20000630)
{
throw new EXRFormatException("Invalid or corrupt EXR layout: First four bytes were not 20000630.");
}
var versionValue = reader.ReadInt32();
Version = new EXRVersion(versionValue);
Headers = new List <EXRHeader>();
if (Version.IsMultiPart)
{
while (true)
{
var header = new EXRHeader();
header.Read(this, reader);
if (header.IsEmpty)
{
break;
}
Headers.Add(header);
}
throw new NotImplementedException("Multi part EXR files are not currently supported");
}
else
{
if (Version.IsSinglePartTiled)
{
throw new NotImplementedException("Tiled EXR files are not currently supported");
}
var header = new EXRHeader();
header.Read(this, reader);
Headers.Add(header);
}
OffsetTables = new List <OffsetTable>();
foreach (var header in Headers)
{
int offsetTableSize;
if (Version.IsMultiPart)
{
offsetTableSize = header.ChunkCount;
}
else if (Version.IsSinglePartTiled)
{
// TODO: Implement
offsetTableSize = 0;
}
else
{
var compression = header.Compression;
var dataWindow = header.DataWindow;
var linesPerBlock = GetScanLinesPerBlock(compression);
var blockCount = (int)Math.Ceiling(dataWindow.Height / (double)linesPerBlock);
offsetTableSize = blockCount;
}
var table = new OffsetTable(offsetTableSize);
table.Read(reader, offsetTableSize);
OffsetTables.Add(table);
}
}
