public Png(string fileName)
{
using (Stream stream = new FileStream(fileName, FileMode.Open))
{
using (PngBinaryReader reader = new PngBinaryReader(stream))
{
reader.ReadSignature();
// Header lesen
Chunk chunk = reader.ReadChunk();
if ((chunk.Length != 13) || (chunk.Type != PngHelper.TxtToInt(PngHelper.IHDR)))
{
throw new InvalidDataException("Wrong IHDR Chunk!");
}
header = PngHelper.ConvertIHDR(chunk);
using (MemoryStream outMemoryStream = new MemoryStream())
{
// Daten Stream bis zum Ende
while (chunk.Type != PngHelper.TxtToInt(PngHelper.IEND))
{
if (chunk.Type == PngHelper.TxtToInt(PngHelper.IDAT))
{
outMemoryStream.Write(chunk.Data, 0, chunk.Data.Length);
dataChunk = chunk;
}
chunk = reader.ReadChunk();
}
}
}
}
}
public int ReadDWord()
{
return(PngHelper.DWordToInt(ReadInt32()));
}