Color image compression
The default image compression algorithm makes use of colour palettes to reduce the overall size of all images. This algorithm
works well as long as the number of colours does not exceed 256.
The 256-color compression algorithm computes the mostly used 256 colors in an image and replaces all other color pixels by their
closest match. This lossless compression algorithm works usually very well with most applications but is relatively slow on large
images with a greater number of colours.
The JPEG compression algorithm produces excellent results with real life true colour images with a small distortion of the source
image. It is not recommended for graphics other than real pictures.
When JPEG compression is selected, the JPEG compression level selection box appears. JPEG compression levels vary from 1 to
9. Level 1 produces poorer quality images with a very large compression ratio. Level 9 produces very good quality images with
medium compression ratio. The default value is 7, which will produce compression levels and image quality suitable for most
This algorithm analyses each image separately and tries to apply the compression algorithm that is best suited to that image.
Remove duplicate images
If the same image is repeated multiple times inside a documentand this option is checked,the image will exist only once in the
PDF document, hence reducing the PDF file size. Setting this option will slow down the conversion speed depending on the
number of images in the document.
Downsample high resolution images
Images used in a document can sometimes be at a much higher resolution than the printer resolution. Downsampling reduces the
PDF file size by adjusting the image resolution to the printer’s resolution.
Disable direct PNG/JPEG printing
This option instructs the GDI to senduncompressed images.