PDF Compression (Version 1.0.0): Functions and Operations

PDF Compression: This adapter compresses PDF documents that exceed a certain size. Documents with a size below 100 KB are compressed only slightly, here the file size can hardly be reduced with the adapter.

Note:

For error-free compression of the PDF document, at least one of the following parameters must be set in the PDF Compression Adapter:

regularCompression
maximumCompression
xRefCompression
mergeResources
quantize with the numColors and alphaThreshold parameters

Properties

Operation

Defines the operation executed by the function adapter

Possible values:

Compress: Compresses a PDF document

Parameters

`Adapter`	Main adapter class (do not change!) Possible values: de.softproject.x4.adapter.PDFCompression: Main class (Default)
`documentPassword`	(optional) Password for encrypting the PDF document Possible values: Character string in password format
`regularCompression`	The PDF is reduced in size using regular compression. Note: If only this parameter is set, low compression is to be expected. Possible values: `true`: The PDF is reduced in size using regular compression. `false`: The PDF is not reduced in size using regular compression.
`maximumCompression`	The PDF is compressed with the maximum value. Best results are achieved in combination with the parameter `regularCompression`. Note: Activating this parameter can increase the runtime. For `maximumCompression,` ZLIB Compression Level 9 is used, which offers the best possible reduction in file size, but has the slowest compression. Possible values: `true`: The PDF is compressed with the maximum value. `false`: The PDF is not compressed with the maximum value.
`xRefCompression`	The PDF is saved in a compressed xRef table (Cross Reference table). This option is only valid for PDFs from version 1.6 or higher and is not compatible with PDF/A-1 files. Note: Activating this parameter can increase the runtime. With this parameter, the file size can be reduced by 5 to 5 % if the PDF that is to be compressed has not been compressed previously with xRef Compression. Possible values: `true`: The PDF is saved in a compressed xRef table. `false`: The PDF is not saved in a compressed xRef table.
`mergeResources`	Merges duplicate resources (fonts, color spaces, bitmap images) to reduce the file size. Note: If the PDF file only has few resources, compression will be low. It makes sense to use this parameter if: there are duplicate images a PDF file is to be compressed, that was previously merged from several documents Possible values: `true`: Merges duplicate resources. `false`: Does not merge duplicate resources.
`quantize`	Quantizes images using the parameters `numColors` and `alphaThreshold`. If the parameter `quantize` is set, also the parameter `numColors` and `alphaThreshold` have to be set. Note: In some cases, the parameter `quantize` can lead to an increase in file size and change the quality and transparency of the images in the PDF. This parameter should not be set if high-resolution images are desired in the PDF. Possible values: `true`: Quantizes images. `false`: Images are not quantized.
`numColors`	The number of colors in images in a PDF. This parameter indicates to which number the number of colors in the PDF shall be reduced to. The values must be a power of two (2n). Possible values: `256` (default) Integer
`alphaThreshold`	Specifies how the transparency is to be handled. Values above 128 lead to higher transparency, values below to lower transparency. Possible values: `128` (default) Integer

Status values

`1`	The operation has been executed successfully.
`0`	The operation has been executed successfully, but without result.
`-1`	The adapter could not be executed.