Class JpegDirectory


  • public class JpegDirectory
    extends Directory
    Directory of tags and values for the SOF0 JPEG segment. This segment holds basic metadata about the image.
    • Field Detail

      • TAG_DATA_PRECISION

        public static final int TAG_DATA_PRECISION
        This is in bits/sample, usually 8 (12 and 16 not supported by most software).
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        Constant Field Values
      • TAG_IMAGE_HEIGHT

        public static final int TAG_IMAGE_HEIGHT
        The image's height. Necessary for decoding the image, so it should always be there.
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        Constant Field Values
      • TAG_IMAGE_WIDTH

        public static final int TAG_IMAGE_WIDTH
        The image's width. Necessary for decoding the image, so it should always be there.
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        Constant Field Values
      • TAG_NUMBER_OF_COMPONENTS

        public static final int TAG_NUMBER_OF_COMPONENTS
        Usually 1 = grey scaled, 3 = color YcbCr or YIQ, 4 = color CMYK Each component TAG_COMPONENT_DATA_[1-4], has the following meaning: component Id(1byte)(1 = Y, 2 = Cb, 3 = Cr, 4 = I, 5 = Q), sampling factors (1byte) (bit 0-3 vertical., 4-7 horizontal.), quantization table number (1 byte).

        This info is from http://www.funducode.com/freec/Fileformats/format3/format3b.htm

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        Constant Field Values
      • TAG_COMPONENT_DATA_1

        public static final int TAG_COMPONENT_DATA_1
        the first of a possible 4 color components. Number of components specified in TAG_NUMBER_OF_COMPONENTS.
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        Constant Field Values
      • TAG_COMPONENT_DATA_2

        public static final int TAG_COMPONENT_DATA_2
        the second of a possible 4 color components. Number of components specified in TAG_NUMBER_OF_COMPONENTS.
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        Constant Field Values
      • TAG_COMPONENT_DATA_3

        public static final int TAG_COMPONENT_DATA_3
        the third of a possible 4 color components. Number of components specified in TAG_NUMBER_OF_COMPONENTS.
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        Constant Field Values
      • TAG_COMPONENT_DATA_4

        public static final int TAG_COMPONENT_DATA_4
        the fourth of a possible 4 color components. Number of components specified in TAG_NUMBER_OF_COMPONENTS.
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        Constant Field Values
    • Constructor Detail

      • JpegDirectory

        public JpegDirectory()
    • Method Detail

      • getName

        public java.lang.String getName()
        Description copied from class: Directory
        Provides the name of the directory, for display purposes. E.g. Exif
        Specified by:
        getName in class Directory
        Returns:
        the name of the directory
      • getComponent

        public JpegComponent getComponent​(int componentNumber)
        Parameters:
        componentNumber - The zero-based index of the component. This number is normally between 0 and 3. Use getNumberOfComponents for bounds-checking.
        Returns:
        the JpegComponent having the specified number.