Package com.pixelmed.dicom

Class OtherByteAttributeOnDisk

java.lang.Object
com.pixelmed.dicom.Attribute
com.pixelmed.dicom.OtherAttributeOnDisk
com.pixelmed.dicom.OtherByteAttributeOnDisk
public class OtherByteAttributeOnDisk extends OtherAttributeOnDisk

A concrete class specializing Attribute for Other Byte (OB) attributes whose values are not memory resident.

Though an instance of this class may be created using its constructors, there is also a factory class, AttributeFactory.

See Also:

  • Constructor Details

    • OtherByteAttributeOnDisk

      public OtherByteAttributeOnDisk(AttributeTag t)

      Construct an (empty) attribute.

      Parameters:
      t - the tag of the attribute

    • OtherByteAttributeOnDisk

      public OtherByteAttributeOnDisk(AttributeTag t, long vl, DicomInputStream i, long byteOffset) throws IOException, DicomException

      Read an attribute from an input stream.

      Parameters:
      t - the tag of the attribute
      vl - the value length of the attribute
      i - the input stream
      byteOffset - the byte offset in the input stream of the start of the data
      Throws:
      IOException
      DicomException

    • OtherByteAttributeOnDisk

      public OtherByteAttributeOnDisk(AttributeTag t, Long vl, DicomInputStream i, Long byteOffset) throws IOException, DicomException

      Read an attribute from an input stream.

      Parameters:
      t - the tag of the attribute
      vl - the value length of the attribute
      i - the input stream
      byteOffset - the byte offset in the input stream of the start of the data
      Throws:
      IOException
      DicomException

  • Method Details

    • getPaddedVL

      public long getPaddedVL()
      Description copied from class: Attribute

      Get the value length of this attribute, accounting for the need for even-length padding.

      Overrides:
      getPaddedVL in class Attribute
      Returns:
      the value length (padded to an even length)

    • write

      public void write(DicomOutputStream o) throws DicomException, IOException
      Description copied from class: Attribute

      Write the entire attribute (including values) to the output stream.

      Specified by:
      write in class Attribute
      Parameters:
      o -
      Throws:
      IOException
      DicomException

    • getByteValues

      public byte[] getByteValues() throws DicomException

      Get the values of this attribute as a byte array.

      This allocates a new array of sufficient length, which may fail if it is too large, and defeats the point of leaving the values on disk in the first place. However, it is a fallback for when the caller does not want to go to the trouble of creating a MappedByteBuffer from the file, or more likely is not even aware that the attribute values have been left on disk, because AttributeFactory silently created an instance of this class rather than an in-memory OtherByteAttribute.

      Overrides:
      getByteValues in class Attribute
      Returns:
      the values as an array of bytes
      Throws:
      DicomException - thrown if values cannot be read

    • getByteValuesPerFrame

      public byte[][] getByteValuesPerFrame(int numberOfFrames) throws DicomException

      Get the values of this attribute as multiple byte arrays, one per frame.

      Caller needs to supply the number for frames so that pixel data can be split across per-frame arrays (since not necessarily known when this attribute was created or read.

      This allocates new arrays of sufficient length, which may fail if they are too large, and defeats the point of leaving the values on disk in the first place. However, it is a fallback for when the caller does not want to go to the trouble of creating a MappedByteBuffer from the file, or more likely is not even aware that the attribute values have been left on disk.

      Parameters:
      numberOfFrames - the number of frames
      Returns:
      the values as an array of arrays of bytes
      Throws:
      DicomException - thrown if values cannot be read

    • getByteValuesForSelectedFrame

      public byte[] getByteValuesForSelectedFrame(int frameNumber, int numberOfFrames) throws DicomException

      Get the value of this attribute as a byte array for one selected frame.

      This allocates a new array of sufficient length, which may fail if it is too large, and defeats the point of leaving the values on disk in the first place. However, it is a fallback for when the caller does not want to go to the trouble of creating a MappedByteBuffer from the file, or more likely is not even aware that the attribute values have been left on disk, because AttributeFactory silently created an instance of this class rather than an in-memory OtherByteAttribute.

      Parameters:
      frameNumber - from 0
      numberOfFrames - the number of frames
      Returns:
      the values as an array of bytes
      Throws:
      DicomException - thrown if values cannot be read

    • getVR

      public byte[] getVR()

      Get the value representation of this attribute (OB).

      Overrides:
      getVR in class Attribute
      Returns:
      'O','B' in ASCII as a two byte array; see ValueRepresentation