Represents the "HalftoneName" entry of the type 1 halftone dictionary object.

It is an optional entry defined as part of the PDF 1.0 specification.

It contains a string representing a PDF string object.

This string contains raw byte data. So it looks like a string but really it is just a wrapper for data.

For definitive details see:.

The ISO PDF Specification, ISO 32000-1:2008 PDF 1.7; Table: 130, page 309.

The ISO PDF Specification, ISO 32000-2:2017 PDF 2.0; Table: 128, page 371.

Although the property type is a string, the underlying PDF object is a string of raw bytes rather than a human-readable text string. The bytes can take any value and do not represent encoded characters.

Some output devices use this value to match the halftone against a built-in screen stored in the device. When a match is found, the device may apply its own internal data instead of the Frequency, Angle, and SpotFunction values in the dictionary.