You may already know how to take screen or a portion of the screen in Mac OS X. You can press ⌘,Shift,3 keys to capture the entire screen or ⌘,Shift,4 to capture a rectangular portion of the screen. By default the screenshots will be stored as .png files. But you can easily change the default settings anytime and can save the screenshots as .jpg, .pdf, .gif or .tiff file format. Here, first we have changed the default settings to save the screenshots as .pdf files later we have changed it to .jpg.
As per your requirements you may change the default format anytime:
.jpg/.png: Suitable for web uploads or for using in blog posts.
.gif: Because of the lowest size on disk, it’s suitable as resources of .css files (as it can reduce the loading time of a website).
.tiff: Suitable for Printing.
.pdf: Suitable when you are capturing Web pages, rich-documents, Capturing applications like Numbers, Pages.
On the Mac, you can just change a setting and all your new screenshots will be saved as JPEGs instead of PNGs. But on iOS you must do that conversion yourself. And for that, you’ll need an app. One option if you need it as JPEG rather than PNG is to open the PNG file (double-click) in Preview and then on the Preview File menu use the Export command which will allow you to export it as JPEG. Another option is to use Skitch for the screenshot and export directly from it to JPEG. All screenshots you take now on your Mac will be saved as JPG files. You can revert back to PNG files by using the same Terminal command, but replace jpg with png. If you want to change the file format of screenshots you’ve already taken, you can use an image converter like Permute.
1. Open Terminal: While you are in Finder press Shift,⌘,A to open Applications and then click on Terminal. You can also open Launchpad and search for Terminal.
2. Now in terminal run below commands to change the screen-capture format to .pdf.
defaults write com.apple.screencapture type pdf;
killall SystemUIServer;
Now take screenshot by pressing ⌘,Shift,3 or ⌘,Shift,4, you will find that the screenshot has been saved as a .pdf file.
run below commands to change the screen-capture format to JPEG.defaults write com.apple.screencapture type jpg;
killall SystemUIServer;
The process is same for .gif, .tiff or to revert back to default .png. That’s it.