Scalable Vector Graphics — the SVG format — is fundamentally separate from JPG. JPG saves pictures as a grid of pixels, SVG saves images as geometric descriptions of geometric shapes. Meaning SVG graphics scale to any size — from a 16x16 pixel favicon to a billboard — without any loss of sharpness.
Changing JPG to SVG is a operation called vectorization, and it is particularly valuable for logos and flat artwork.
When converting JPG to SVG, it is necessary to realize what the conversion actually does. JPG files are a bitmap image — a set grid of image pixels. An SVG is a mathematical image — a collection of paths which software uses to draw the artwork.
Results are excellent for clean images with clear shapes and minimal colors — more info icons, logos, symbols and line art. It works less well for detailed photographs with fine detail.
For best output, Illustrator's Image Trace function provides the most precision. Open your JPG in Illustrator, highlight the image, access the Image Trace panel and pick an suitable option.
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