There is a difference between the difference between bitmap and vector graphics. Bitmap art is made of pixels and has a scale: Each pixel represents black or white, or some gray or hue. The resolution of the file – how many pixels wide by how high – defines the amount of information in it. Scale it up and you begin to see the individual pixels.
However, a vector graphic defines only the relationship between arcs and lines, which can be colored or filled with toner or patterns, and can be scaled to any size large or small. At what size they are scaled, they give the screen: the geometric data is converted to pixels for display. (Text included in vector files is almost always made by vectors themselves!)
It is not uncommon for you to have vector art that you want to use as a picture on a website or in software that cannot import a given format. That vector art can be an EPS (Encapsulated PostScript) file, a format dating back to decades, and associated with Adobe Illustrator; or SVG (scalable vector graphics), a newer specification developed for web screens and widely used. (Why does an SVG when you can only include it on a website? SVGs take processing power and have other limitations to bitmaps.)
Vector art also sweeps in PDF files, which can combine type, vector and bitmap images . PDF files are always rendered when viewed as regardless of the zoom ratio you are watching.
I have been sent vector art to use as the company logo on a project, as well as to receive PDF files that contain a mixture of material that I must flatten into a bitmap for a particular size. Sometimes the material does not exist in another format ̵
Previewer  The Mac Previewer can help with all of this. While often viewed as a PDF viewer, it can read vector formats, render them, and let you either export flat bitmaps – or you can take a shortcut I'll explain.
You can just drag an EPS or PDF file to Preview or select it from File > open . SVG files must first pass through Safari, which will do them, and then select File > Export as PDF to create a file that can be read in Preview.
With the file open in Preview, select only File > Export and then select the type of output you want from the Format pop-up menu.
Some tips will help you further:
For the common formats of PNG, JPEG and TIFF, select an output resolution by evaluating Final size where you want to render the resulting image. For Retina display on a web page, you want the file to be 144 pixels per inch at 100 percent of the intended size. To find the scale, select Tools > View Inspector and then select Edit > View Markup Toolbar . Click on the selection rectangle at the top left, and wherever you go, the inspector will display the size of the scale as in inches. You can also use it to crop by selecting Tools > Crop with an active selection.
With JPEG, you can move a slider from the lowest to the best to control how much detail and color fidelity is preserved. By testing different settings, you can push at least, and see how much less a JPEG export is while keeping the degree of accuracy and clarity you want.
Preview does not allow you to select individual pages when exporting a multipage PDF file. For a PDF with many pages, you may want to copy some pages to another PDF before exporting.
If the export option is too fussy, it is a quick shortcut: use macOS built-in screen selection screen recordings. Press Command-Shift-4 and drag the selection slider around the portion of the image in the Preview you want to use. The resulting image is stored on the desktop.
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