Difference Between JPEG and RAW


JPEG and RAW are two of the image file formats. More formally, RAW is a type of image file that is minimally processed and JPEG is a method of digital image compression. Cameras first save the images to RAW format temporally, and then convert to JPEG using the white balance and other attributes set in the camera by the user. Then the RAW files are usually deleted.

What is RAW?

A RAW file is a file format for image files that contain data that are processed minimally. RAW files contain data from digital cameras, image scanners or film scanners that gets input through image sensors. RAW files get their name because the content is not processed. So, RAW files are not suitable to be printed or edited without processing. RAW files are often called digital negatives (because they are similar to the negatives in film photography). Just like negatives, RAW files cannot be directly used as an image (but they do contain all the information to recreate the image). The conversion of a raw image file is called developing (again analogous to the film development).

Usually by processing the RAW file using a wide-gamut internal colorspace, necessary adjustment needed to convert it to “positive” file formats (e.g. TIFF or JPEG) or printing can be precisely made. This ultimately results in a device dependent colorspace. Even though, all the RAW files are categorically called RAW image files, there are many file formats that belong to this family (e.g. .3fr, .ari and .dcr). These different file formats are used by different digital cameras. The goal of having an image in the RAW format is to minimize the loss of information from the data extracted from the image sensor. Therefore, RAW files usually contain wider range of colors than the eventual final format.

What is JPEG?

JPEG is a method of compression that can be used for creating lossy compressed digital images. JPEG (Joint Photographic Experts Group) group created this standard for compression. In order to compromise between size and quality, the degree of compression can be selected. You can achieve 10:1 compression without loosing much of the image quality. Many image file formats use JPEG compression. For example, JPEG/Exif image file format is used by digital cameras and JPEG/JFIF is used for images on web sites. But all these are called simply JPEG files. The Mime types image/jpeg or image/pjpeg are reserved for the JPEG file format.

What is the difference between JPEG and RAW?

RAW is a negative image format, while JPEG is a positive image format. JPEG is a universal format, while RAW is a manufacturer dependent format. Therefore, usually dedicated software is required to read RAW files. But any generic image viewer can be used to view JPEG files. So, if you take your pictures in RAW format, and you don’t have the updated software in the computer, you are unable open the files. Sometimes you may need to buy software to open RAW files (depending on the file’s actual extension). And for shooting action, RAW is not suitable, because RAW files are large in size.