Details of the file format specifications required for Landonline images can be found in Landonline scanning requirements:
- TIFF format
- CCITT Group 3 or Group 4 Fax Compression
- Black and white only
- Resolution 150-300dpi
- Multi-page TIFF
Below, each component of the required file format, plus other scanning terminology, is explained.
File format refers to the way that information is organised inside a computer file. Different file formats have different advantages depending on the type of information that they hold and what the information will be used for. For Landonline documents, a specific kind of image file format – Tagged Image File Format (TIFF) – is the chosen, suitable format.
|TIFF: Tagged Image File Format|
Tagged Image File Format (TIFF) is a file format that is suitable for storing images of documents. TIFF is used in Landonline because it is stable, robust, mature, widely supported and can store multiple pages within a single file.
|CCITT Group 3 or Group 4 Fax Compression|
The international standards for file compression are set by CCITT (Comité consultatif international téléphonique et télégraphique, or International Telephone and Telegraph Consultative Committee). CCITT Group 4 Fax is the standard specification for making document image files smaller or compressing them. It ensures a small file size by making the image black and white ("fax") and by applying other complex techniques (Group 4 compression algorithms).
CCITT Group 4 Fax is a common method for compressing and encoding TIFF files (it converts them to Group 4). Landonline is also able to upload CCITT Group 3 Fax compression image files. However, it is important to note that CCITT Group 3 Fax compression image files are generally larger than Group 4 and will therefore take longer to upload into Landonline. For this reason, CCITT Group 4 Fax compression image files are preferred.
Note that some Group 3 settings could cause the Landonline TIFF converter to not convert and display all the pages.
|Resolution / dpi = Dots Per Inch|
On a computer, an image is made up of dots (or "pixels"). The more dots there are per inch, the greater the resolution and the more detailed the image can be. However, the trade-off is that higher-resolution (higher dpi) images have a larger file size (i.e., they take up more space on your computer and take longer to upload). Landonline’s specification of 150-300dpi balances image quality and file size.
DPI is sometimes called pixels per inch (ppi) or samples per inch (spi).
|Black and White Only|
Dealing document images in Landonline are stored as black and white (or "fax") to minimise file size. The more colours there are in an image (the greater the "colour depth"), the larger the file size. For Landonline dealing documents, colour is not important. Greyscale files are also much larger.
Scanned images are often created as one file per page scanned. For submitting to Landonline, however, a scanned document must be saved as a single file even if it has multiple pages. A multi-page TIFF allows all pages of a document to be stored within a single TIFF file. You should ensure that your scanning software allows you to create multi-page TIFFs if you need to attach such images to Landonline. If you are unsure whether your scanner software is able to create multi-page TIFFs, you should contact your scanner supplier.
A scanner is the hardware device that converts images and printed text into a digital image file. Many scanners work in tandem with scanning software on your computer to generate an image file of the format that you choose.
Scanning software is the computer software that "talks" to your scanner and turns the image that your scanner "sees" into a digital image file of a specific file format. Many scanners need the scanning software to be installed on your computer, whereas other high-end scanners have the scanning software built in. Different scanning software allows different file formats, so you should ensure that your scanning software allows you to produce images in the required format for Landonline. Usually, scanning software is packaged with a scanner when you purchase it.
The print-to-TIFF driver is a piece of LINZ software that allows you to convert other file types into Landonline-compatible TIFF image files. In Windows, it appears in your list of printers. However, instead of printing to a piece of paper, it creates a new TIFF file that is compatible with Landonline. The print-to-TIFF driver can be downloaded from software downloads.