"PDF compression" refers to the process of reducing the file size of a PDF file by removing unnecessary data or encoding it more efficiently without significantly compromising the quality of the information contained therein.
Typical features of PDF compression software include:
Image compression: Reducing file size by compressing images within the PDF file, either through lossy or lossless compression techniques.
Text optimization: Removing redundant information from text, such as invisible objects or duplicates, to decrease file size.
Font subsetting: Removing unnecessary characters from embedded fonts to reduce file size while maintaining readability.
Compression of embedded files: Compressing and optimizing embedded files such as graphics, audio, or video within the PDF to reduce overall size.
Resolution adjustment: Reducing image resolution to decrease file size while maintaining acceptable quality.