Developer(s) Apple Operating system Website apple.com | Development status Active License Proprietary | |
Stable release 9.0 (macOS version) / August 19, 2016; 7 months ago (2016-08-19) | ||
Preview is the image viewer and PDF viewer of the macOS operating system; it enables users to view and print digital images and Portable Document Format (PDF) files. Like macOS itself, it originated in the NeXTSTEP operating system from NeXT.
Contents
- Supported file types
- Editing features PDF
- Editing features Image files
- Import and export
- New Features in Version 7
- References
Preview uses Apple's implementation of the PDF specification, the Aqua graphical user interface, the Quartz graphics layer, and the ImageIO and Core Image frameworks.
Preview is known to freeze or crash randomly, sometimes taking the entire computer with it. Users have made Apple aware of these issues, but they are unfixed after several releases of OS X.
Supported file types
Preview can open the following file types:
The version of Preview included with OS X 10.3 could loop animated GIFs via an optional "play" button that could be added to the toolbar. With OS X 10.4, Preview lost playback functionality and animated GIFs would instead display as individual frames in a numbered sequence.
Editing features - PDF
As of OS X 10.9.2 Preview does not support ISO-standardized PDF (ISO 32000), and when saving, destroys aspects of PDF files without warning to the user.
Preview can also encrypt PDF documents, and restrict their use; for example, it is possible to save an encrypted PDF so that a password is required to copy data from the document, or to print it. However, encrypted PDFs cannot be edited further, so the original author should always keep an unencrypted version.
Some features which are otherwise only available in professional PDF editing software are provided by Preview: It is possible to extract single pages out of multi-page documents (e.g. PDF files), sort pages, and drag & drop single or multiple pages between several opened multi-page documents, or into other applications, such as attaching to an opened email message.
PDF and TIFF documents can also be annotated and supplied with keywords, and are then automatically indexed using macOS's system-wide Spotlight search engine.
OCR PDF document creation —usually from scanned physical documents— in order to make their text searchable, is not available with Preview, though sometimes the scanner or all-in-one printer used to obtain the document image often has some manufacturer software to do this.
Editing features - Image files
Preview offers basic image correction tools using Core Image processing technology implemented in macOS, and other features like shape extraction, color extraction, cropping, and rotation tools.
Import and export
Preview can directly access image scanners supported by macOS and import images from the scanner. Preview can convert between image formats; it can export to BMP, JP2, JPEG, PDF, PICT, PNG, SGI, TGA, and TIFF. Using macOS's print engine (based on CUPS) it is also possible to "print into" a Postscript file, a PDF-X file or directly save the file in iPhoto, for example scanned photos.
Beginning with Mac OS X 10.7 Lion, Preview restricts the Format option popup menu in the Save As dialog to commonly used types. It is possible to access the full format list by holding down the Option key when clicking the Format popup menu. (GIF, ICNS, JPEG, JPEG-2000, Microsoft BMP, Microsoft Icon, OpenEXR, PDF, Photoshop, PNG, SGI, TGA, TIFF)
New Features in Version 7
A new "edit button" where the picture can be edited is introduced in Version 7. The "edit button" allows options to insert shapes, lines, do cropping, and among other things.