Output Options

I.R.I.S. Hyper compression (iHQC)

What is it?

iHQC stands for intelligent High-Quality Compression. It is a I.R.I.S proprietary implementation of mixed raster content compression method (MRC). It relies on image segmentation to fine-tune the compression rate applied to input images.

iHQC mode uses several compression algorithms: JPEG, JPEG2000, TIFF and JBIG2.

To use iHQC mode, use the PageDisplay::HyperCompression Option.
To set the hypercompression algorithms, use the CPdfCompressionOptions Class and set the Bitonal and Color formats.
The bitonal algorithm compresses the text layer and black and white documents. The color algorithm compresses the background and foreground layers on color and grayscale documents.

PDF options matrix

Note

✔ The option is available ✘ The option is NOT available

Table 1. PDF Options availability

PDF Version	Embed font	Encryption	Attachment list	Use JPEG 2000 Available in PdfCompressionOptions
PDF 1.4	✔	✔	✔	✘
PDF 1.5	✔	✔	✔	✔
PDF 1.6	✔	✔	✔	✔
PDF 1.7	✔	✔	✔	✔
PDF 1.7.3	✔	✔	✔	✔
PDF 1.7.5	✔	✔	✔	✔
PDF 1.7.8	✔	✔	✔	✔

PDF/A options matrix

Note

✔ The option is available ✘* The option is NOT available. Always OFF due to compliance reasons ✘** The option is NOT available. Always ON due to compliance reasons

Table 2. PDF/A Options availability

PDF/A Version	Embed fonts	Encryption	Attachment list	Use JPEG 2000 Available in PdfCompressionOptions
TEXT AND GRAPHICS TEXT OVER IMAGE
PDF 1.4_A1a	✘**	✘	✘	✘*
PDF 1.4_A1b	✘**	✘	✘	✘*
PDF 1.7_A2a	✘**	✘	✘	✔
PDF 1.7_A2b	✘**	✘	✘	✔
PDF 1.7_A3a	✘**	✘	✔	✔
PDF 1.7_A3b	✘**	✘	✔	✔
IMAGE OVER TEXT HyperCompressed
PDF 1.4_A1a	✔	✘	✘	✘*
PDF 1.4_A1b	✔	✘	✘	✘*
PDF 1.7_A2a	✔	✘	✘	✔
PDF 1.7_A2b	✔	✘	✘	✔
PDF 1.7_A3a	✔	✘	✔	✔
PDF 1.7_A3b	✔	✘	✔	✔