JPG is the world’s most popular digital image format and it is a lossy compression system, which basically means the bigger the compression of the file, the smaller the size, but the overall quality of the image will suffer.
On the other hand, if a user chooses a smaller compression rate, the file will be much larger, and the quality will remain amazing.
JPGs compression functions by exploiting the eye’s natural imbalance of differentiating the amount of light that an image has, and our perception of color differences. The eye can detect the subtle changes in lighting conditions far better than the changes in color (this is why we almost see completely black and white in poor light conditions). JPG focuses its compression on the color-part of data, and leaves the lighting part intact.
PDFs are mostly converted to JPG for extraction of images from PDF files that usually contain parts that are visual in nature (like pictures, images, graphs), and other textual parts.
So if we want to isolate the pictures from the text, we’ll use PDF to JPG conversion.
If we require to edit the image that’s inside of a PDF file in any way imaginable, we firstly have to convert the PDF to JPG.
This is because the PDF has a read-only nature, which doesn’t allow any kind of editing prior to the conversion, which returns the file into a perfectly editable native state.