Compressions and Optimizations

There are 2 types of compressions which are Lossy and Lossless:

Lossy Compression

Lossy compression refers to compression in which some of the original file's (JPEG) data is lost. The process is irreversible; once you've converted to lossy, there's no turning back. And the more users compress it, the worse it degrades. Both JPEGs and GIFs are lossy image formats.

One of the most obvious advantages of using lossy compression is that it results in a significantly smaller file size (smaller than the lossless compression method), but it also means that quality is sacrificed. Most tools, plugins, and software allow the user to select the level of compression users want to use.

Photos are made up of millions of pixels, and the difference in color between one pixel and an adjacent pixel can be undetectable. JPEG capitalizes on this by storing fewer color codes. Under standard settings, a single color is recorded for every block of nine pixels, resulting in a 90 percent reduction in file size.

Lossless Compressions

The inverse of Lossy Compression. Lossless files are typically used during the production process when files must be passed around to various team members to be edited, stored, or manipulated. If lossy compression has been used in this phase, the original file's quality would be reduced each time it was passed along the pipeline to something else.

One common method of compressing files without losing data is to use an application such as WinRAR, which compresses multiple files together, shrinking the overall size while maintaining quality when the file is unzipped later.

When it comes to reducing the file size of an image or video, compression is essential. The smaller the file, the more compression applied to the original asset. The trade-off is that overall quality suffers as a result. 'Good' lossy compression occurs when the final output asset is small in size, but the quality loss is not noticeable.

Optimizing

Optimization is simply achieving the ideal balance between image quality and file size; this can vary depending on the image's intended use. Many factors are taken into account when optimizing an image, for example, when uploading an image to the internet, the JPEG file format is ideal because it has good image quality and a small file size, allowing the image to load quickly on the website.

Optimizing is used on nearly every single digital graphic. The main purpose of optimizing is to create a higher quality visual graphic to be displayed. Optimizing would and is used for a variety of contexts such as placing images on a website, creating backgrounds, displaying products and promotions, and even in some cases creating digital catalogues that can be accessed over the internet.

The main advantage of optimization is that it allows you to achieve the desired effect, such as reducing file size when necessary and increasing image quality when essential.

Dimensions – Image dimensions refer to the length and width of a digital image; by controlling the dimensions of the graphic, users can make the image smaller or larger depending on its purpose or location. When the graphic's dimensions are changed, the volume of pixels remains constant; the only difference is that the larger the image, the more space the pixels must cover.

Bit Depth – Bit depth is the volume of color per pixel; decreasing the bit depth will obviously reduce the image file size, though image quality is likely to experience; generally, deciding this involves making a choice between having good quality graphics with a relatively slow load time or lower quality graphics that allow the website to perform faster.