M3 file format, compression techniques, image resolution and colour depth

File Format, Compression Techniques, Image Resolution and Colour Depth (M3)

JPEG is a file format used to compress photographic images. JPEG typically achieves 10 to 1 compression with little perceivable loss in image quality.JPEG is the most common image format used by digital cameras and other photographic image capture devices, and is the most common format for storing and transmitting photographic images on the world wide web.

Zip files are single files sometimes called archives, that contain one or more compressed files. Zip files make it easier to keep related files together and make transporting, emailing, downloading and storing data. The Zip format is the most popular compression format used in the Windows environment, and WinZip is the most popular compression utility. To store files in a Zip file, or to access the files in a Zip file, you need a compression utility such as WinZip. WinZip makes it easy for Windows users to work with archives. WinZip features a standard Windows point-and-click drag-and-drop interface for viewing, running, extracting, adding, deleting, and testing files in Zip files. Occasional and first-time users can choose to use the intuitive WinZip Wizard.



Image resolution describes the detail an image holds. The higher the resolution, the higher the detail in the image. resolution quantifies how close lines can be to each other and still be visually resolved.




When you zoom in closely on an image, you begin to see the pixels and in some photo manipulation programs, you can colour in individual pixels to make the quality better. Making and image too big or too small can ruin the quality of an image so this is the problem with manipulation of images.

Colour depth is a term used to describe the number of bits used to represent the colour of a single pixel in a bitmapped image or video frame buffer. This concept is also known as bits per pixel (bpp), particularly when specified along with the number of bits used. Higher color depth gives a broader range of distinct colors.

Demonstration Of File Compressions

Here is a screenshot of how to save my image to web on Photoshop. The current image I am working on is the top image, and the bottom image is the compressed image. It has been changed to a gif file, and I have allowed four colours to be visible on the second image (black, yellow, green and white), the red is not visible. There is also a change in the file sizes, the top image is 284 KB and the bottom image is 3.84 KB so it has been compressed but lost a lot of quality.