### ----------------------------------------------------
### -- PDF::ISO_32000
### -- Licenses: Artistic-2.0
### -- Authors: David Warring
### -- File: resources/ISO_32000/Table_130-Entries_in_a_type_1_halftone_dictionary.json
### ----------------------------------------------------
{
  "table": {
    "caption": "Table 130 – Entries in a type 1 halftone dictionary",
    "head": [
      "Key",
      "Type",
      "Value"
    ],
    "rows": [
      [
        "Type",
        "name",
        "(Optional) The type of PDF object that this dictionary describes; if present, is Halftone for a halftone dictionary."
      ],
      [
        "HalftoneType",
        "integer",
        "(Required) A code identifying the halftone type that this dictionary describes; is 1 for this type of halftone."
      ],
      [
        "HalftoneName",
        "byte string",
        "(Optional) The name of the halftone dictionary."
      ],
      [
        "Frequency",
        "number",
        "(Required) The screen frequency, measured in halftone cells per inch in device space."
      ],
      [
        "Angle",
        "number",
        "(Required) The screen angle, in degrees of rotation counterclockwise with respect to the device coordinate system.\nNOTE Most output devices have left-handed device spaces. On such devices, a counterclockwise angle in device space corresponds to a clockwise angle in default user space and on the physical medium."
      ],
      [
        "SpotFunction",
        "function or name",
        "(Required) A function object defining the order in which device pixels within a screen cell is adjusted for different gray levels, or the name of one of the predefined spot functions (see Table 128)."
      ],
      [
        "AccurateScreens",
        "boolean",
        "(Optional) A flag specifying whether to invoke a special halftone algorithm that is extremely precise but computationally expensive; see Note 1 for further discussion. Default value: false."
      ],
      [
        "TransferFunction",
        "function or name",
        "(Optional) A transfer function, which overrides the current transfer function in the graphics state for the same component. This entry is present if the dictionary is a component of a type 5 halftone (see “Type 5 Halftones” in 10.5.5.6) and represents either a nonprimary or nonstandard primary colour component (see 10.4, \"Transfer Functions\"). The name Identity may be used to specify the identity function."
      ]
    ]
  }
}


