So, if I have an image in BMP file format being 1024 x 768 and 8 bits (bit depth), I can get the size of the image: 1024 x 768 x 8 = 6,291,456; 6,291,456 / 8 x 1024 = 768 Kb, which is correct when I right click on an image and see its size.

Now, if I do the same thing with a JPG or PNG image, I don't get the same file size because JPG and PNG are compressed formats and thus have smaller file sizes.

Is there a way that I can find how much are those JPG and PNG images compressed? Like a percentage value maybe?

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    To figure that out you would need to know the size of the original image before compression as this info is not stored in the meta data. – Moab Feb 29 '20 at 6:45
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    Further, because the original image may have also been compressed in some form, you cannot know with any certainty the original size and therefore you cannot tell the percentage of compression. – music2myear Feb 29 '20 at 6:55
  • Similar question>>>>>>photo.stackexchange.com/questions/88167/… – Moab Feb 29 '20 at 6:59
  • All you can do is determine compression "level" but this is not the same as percentage>>>>imgonline.com.ua/eng/determine-jpeg-quality.php – Moab Feb 29 '20 at 7:01

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