/// <summary>
/// Opens the file for writing.
/// </summary>
/// <returns>The opened file.</returns>
/// <param name="Path">Path to the output file.</param>
/// <param name="Headers">FITS Headers to be written to the file.</param>
public static MMapFitsFile OpenWriteFile(string Path, HeaderTable Headers)
{
FileInfo info = new FileInfo(Path);
int HLength = ((Headers.Count * 80) + 2879) / 2880 * 2880;
int DLength = HeaderIO.ComputeDataArrayLength(Headers) + 2879;
DLength = DLength / 2880 * 2880;
int FLength = HLength + DLength;
MemoryMappedFile mmap = MemoryMappedFile.CreateFromFile(Path, FileMode.Create, Guid.NewGuid().ToString(), FLength, MemoryMappedFileAccess.ReadWrite);
Stream s = mmap.CreateViewStream();
FitsFileBuilder builder = new FitsFileBuilder()
{
PrimaryTable = new HeaderTable()
};
foreach (var w in Headers)
{
builder.PrimaryTable.Add(w.Key, w.Value); s.Write(((FITSMetadataRecord)w.Value).ToRawRecord(), 0, 80);
}
s.Write(Encoding.UTF8.GetBytes("END".PadRight(80)), 0, 80);
while (s.Position < HLength)
{
s.Write(Encoding.UTF8.GetBytes(string.Empty.PadRight(80)), 0, 80);
}
builder.PrimaryDataPointer = HLength;
s.Dispose();
return(new MMapFitsFile(Path, true, null, builder, mmap, MemoryMappedFileAccess.ReadWrite));
}
/// <summary>
/// Open file for reading.
/// </summary>
/// <returns>The opened file.</returns>
/// <param name="Path">Path to the file.</param>
/// <param name="numberGetter">Delegate that generates the image numbers in a MEF FITS.</param>
public static MMapFitsFile OpenReadFile(string Path, MEFImageNumberGetter numberGetter = null)
{
FileInfo info = new FileInfo(Path);
MemoryMappedFile mmap = MemoryMappedFile.CreateFromFile(Path, FileMode.Open, Guid.NewGuid().ToString(), 0, MemoryMappedFileAccess.Read);
Stream stream = mmap.CreateViewStream(0, 0, MemoryMappedFileAccess.Read);
FitsFileBuilder builder = HeaderIO.ReadFileHeaders(stream, info.Length, numberGetter);
stream.Dispose();
return(new MMapFitsFile(Path, false, numberGetter, builder, mmap, MemoryMappedFileAccess.Read));
}
/// <summary>
/// Reads the FITS headers from a stream.
/// </summary>
/// <param name="stream">Input stream.</param>
/// <param name="Length">Expected stream length.</param>
/// <param name="numberGetter">The function which assigns image numbers to FITS images in file.</param>
/// <returns>A FitsFileBuilder containing the information from the headers.</returns>
internal static FitsFileBuilder ReadFileHeaders(Stream stream, long Length, MEFImageNumberGetter numberGetter)
{
FitsFileBuilder builder = new FitsFileBuilder();
var R1 = ReadHeaderFromStream(stream, Length);
builder.PrimaryHeader = R1.Item1;
builder.PrimaryTable = R1.Item2;
/* Setup primary data array. Start looking for extensions. */
builder.PrimaryDataPointer = (int)stream.Position;
int ALength = ComputeDataArrayLength(builder.PrimaryTable);
/* Align to 2880 */
int AALength = (ALength + 2879) / 2880 * 2880;
long NewPosition = stream.Position + AALength;
if (NewPosition > Length)
{
throw new FITSFormatException("Data array longer than file length.");
}
stream.Position = NewPosition;
/* Check if file is MEF. */
if (stream.Position != Length)
{
if (numberGetter == null)
{
numberGetter = DefaultGetter;
}
builder.ExtensionHeaders = new List <List <MetadataRecord> >();
builder.ExtensionDataPointers = new List <int>();
builder.MEFDataPointers = new Dictionary <int, int>();
builder.MEFImagesHeaders = new Dictionary <int, List <MetadataRecord> >();
builder.MEFHeaderTable = new Dictionary <int, HeaderTable>();
/* Read extension headers. */
for (int exn = 0; stream.Position < Length; exn++)
{
var R2 = ReadHeaderFromStream(stream, Length);
int Loc = (int)stream.Position;
ALength = ComputeDataArrayLength(R2.Item2);
builder.ExtensionHeaders.Add(R2.Item1);
builder.ExtensionDataPointers.Add(Loc);
MetadataRecord img;
try { img = R2.Item2["XTENSION"]; } catch (Exception ex) { throw new FITSFormatException("Extension headers do not follow standard.", ex); }
if (img.AsString == "IMAGE ")
{
int ImNr = numberGetter(exn, R2.Item2);
builder.MEFImagesHeaders.Add(ImNr, R2.Item1);
builder.MEFHeaderTable.Add(ImNr, R2.Item2);
builder.MEFDataPointers.Add(ImNr, Loc);
}
AALength = (ALength + 2879) / 2880 * 2880;
NewPosition = stream.Position + AALength;
if (NewPosition > Length)
{
throw new FITSFormatException("Data array longer than file length.");
}
stream.Position = NewPosition;
}
}
return(builder);
}
/// <summary>
/// Opens a FITS File handle from a file on a local disk.
/// </summary>
/// <param name="Path">Path to where the image is stored.</param>
/// <param name="OutputImage">Specifies whether the image is an input or an output one.</param>
/// <param name="numberGetter">Delegate that generates the image numbers in a MEF FITS.</param>
private MMapFitsFile(string Path, bool OutputImage, MEFImageNumberGetter numberGetter, FitsFileBuilder Headers, MemoryMappedFile Handle, MemoryMappedFileAccess Access) :
base(Path, OutputImage, numberGetter, Headers)
{
OpenViews = new Dictionary <IntPtr, MemoryMappedViewAccessor>();
mmap = Handle;
access = Access;
}
/// <summary>Wrapper for underlying constructor.</summary>
protected NSStreamFitsFile(byte[] Data, string Path, bool OutputImage, MEFImageNumberGetter numberGetter, FitsFileBuilder Headers) :
base(Path, OutputImage, numberGetter, Headers)
{
this.Data = Data;
}
protected FitsFile(string Path, bool OutputImage, MEFImageNumberGetter numberGetter, FitsFileBuilder Headers)
{
OutputFile = OutputImage;
this.Path = Path;
PrimaryTable = Headers.PrimaryTable;
PrimaryDataPointer = Headers.PrimaryDataPointer;
ExtensionDataPointers = Headers.ExtensionDataPointers;
MEFHeaderTable = Headers.MEFHeaderTable;
MEFDataPointers = Headers.MEFDataPointers;
}
