Image Formats Defined: Which Should You Utilize?
There are dozens of image file formats out there, each offering benefits in certain situations. JPEGs are great for posting photos to social media and websites while HEIF formats work best with video clips and burst images; PNG images work great when used for logos and other images with transparency features.
JPEG
JPEGs are among the most frequently used image file formats online and in digital cameras, due to their effective compression that makes them smaller than other file types like PNG. Unfortunately, however, many are unfamiliar with what goes into making JPEGs work or how it differs from PNG files.
JPEG compresses data by eliminating redundancies, something the human visual system is good at recognizing in images composed of small blocks with similar digital counts. At the start of its compression process, the JPEG algorithm attempts to mitigate redundancy by comparing adjacent pixels for similarities before discarding some image data to keep images clear and unobscured.
JPEG is a lossy compression format, meaning that some image quality is sacrificed during compression. This may cause artifacts in high-resolution images and those with high compression ratios.
JPEGs remain popular because they provide an ideal balance between quality and file size, making them suitable for websites and social media posts. Unfortunately, JPEGs do not do well when used for text or line art due to blurring edges; additionally they cannot scale without losing clarity when resized frequently - thus increasing popularity of PNGs, SVGs and AVIF formats.
PNG
PNG images are an ideal format for images requiring transparency, while still storing rich details like patterns, gradients and textures. PNG was developed as an enhanced non-patented alternative to GIF, featuring three key benefits - an expanded color palette (up to 8 bits per pixel), support for alpha transparency and gamma correction.
Lossless compression algorithms preserve original data without discarding any information, making this technique ideal for printing or use in digital art where every pixel counts. Furthermore, web designers find it highly suitable as it supports transparent backgrounds while maintaining high quality even when compressed.
PNG files contain pixels represented by one or more numbers that either represent indexes into a palette (in the PLTE chunk) or actual sample data (in the PIXEL chunk), with each number representing either an unindexed color value, an arithmetic float number, or decimal numbers indexed or unindexed respectively.
Standardized versions of compression processes use filter types adaptively on a line-by-line basis to improve performance compared to old DPCM algorithms and other modern filters. Although documented and implemented widely in PNG-writing software, this improvement has yet to reach a point where it could be considered general purpose compression.
TIFF
TIFF (Tagged Image File Format) was jointly developed in the 1980s by Aldus and Microsoft (now owned by Adobe) as an ideal format for high quality image printing, editing and sharing across industries. Now owned by Adobe, TIFF remains popular across a number of fields due to its wide usage.
TIFF files offer lossless compression, which means no data is lost during their compression process, making them ideal for protecting images with intricate details or for editing purposes. Unfortunately, due to this trait TIFFs tend to be larger in file size.
TIFF files offer another unique advantage for graphic design and photography: layer support. This enables users to edit an image in various ways - for instance adding or removing elements without altering its original form - making TIFF files highly sought after among professional photographers, printers, publishers and others in these fields.
TIFF provides various color modes and bit depths to meet specific imaging needs, including saving images in 16-bit mode for color preservation beyond what a typical printer or monitor can display, as well as supporting CMYK color models used for print separations.
Web designers rely heavily on file formats when it comes to image production and delivery, and choosing the most efficient and appropriate file types can make a significant impactful statement about how their business runs. By choosing appropriate image file types for raster images or vector graphics, web designers can ensure their images look fantastic, load quickly and are optimized for their websites.
There are hundreds of image file formats, categorized as either raster (pixel-based) or vector (linear) graphics formats. There are also formats designed for lossy and lossless compression as well as various color modes.
Raster image formats typically use 8-16 bits per channel with some support for transparency. They are supported by most modern browsers including Chrome, Firefox, Opera, Internet Explorer and Safari; making them perfect for use as photos, icons, logos, maps or other graphical elements.
PNG is an image format that supports both lossless and lossy compression methods, offering superior text readability over JPEG. PNG files tend to have larger file sizes compared to JPEG formats but are worth their added space as PNG offers superior quality and compatibility across many operating systems and image editors.
PDF may not technically be considered an image format, but it makes an ideal solution for storing, editing and sharing images. Compatible with most systems and secure, there are no restrictions or file size limits with PDF images.