File Formats

FILE FORMATS:  What are PDFs, JPEG, PNG files……?

PDF is Portable Document Format.   It is  a file format was developed by Adobe in the 1990s.   It is a file format used to create documents (including text, formatting and images), so that they can be used on a number of different applications and on both PCs and Mac.

JPEG is well-known file format for images (so-called lossy compression) produced by digital or mobile phone cameras.   The degree of compression of the file can be adjusted.  This allows a selectable trade-off between storage size and image quality.   Modern printing processes normally require jpeg images to be at least 300dpi.

PNG (Portable Network Graphic) is a raster (pixel-based) graphics file format that allows loss-less data compression. Therefore it can be scaled in size with no loss of quality.   PNG was created as an improved replacement for GIF files (Graphics Interchange Format).  It is the most widely used file format on the Internet.

 

Tagged Image File Format, TIFF or TIF, is a computer file format for storing raster graphics images.  It is popular among graphic artists, the publishing industry, and photographers. TIFF is widely used for scanning, OCR (optical character recognition), image storage and some desktop publishing applications.

 

VECTOR AND RASTER FILES?

The difference between vector and raster graphics is that raster graphics are composed of pixels, while vector graphics are composed of paths.

A raster graphic, such as a gif or jpeg, is an array of pixels of various colours, which together form an image.

A vector graphic, such as an .eps file, or Adobe Illustrator (AI) file, is composed of paths.   These paths, or lines, can be straight or curved. They contain the points where the paths start and end, how much the paths curve, and the colours that either border or fill the paths.   They can therefore scaled without losing quality.

Raster graphics, on the other hand, become “blocky,” since each pixel increases in size as the image is made larger. This is why logos and other designs are typically created in vector format – the quality will look the same on a business card as it will on a billboard.

To convert a low quality jpeg file (72dpi) to one at 300dpi just contact The Copy and Print Shop.