Regular JPEG files are already compressed so file compression does not yield substantial space optimization.
Next step would be to compromise on the image size and/or quality for archiving or other purposes.
On Windows, one could manually open JPEGs (if less in number) in MS Paint and save as followed by close to arrive at a much smaller file size with minuscule quality difference. If the files are large in number, then a batch file could be written giving image folder location as input which iteratively opens each image in MS Paint and saves it before closing.
There are a number of available utilities to do the same like jpeg-optimizer, jpegmini-lite etc.
However, OS X also comes with Preview app which can come to our rescue in such cases.
Here is how –
- Open images in Preview app which is usually the default app. If not, one can choose to view it in Preview app.
- Once the Preview app opens, select all images
- Click on File > Export selected
- A popup would open with options to Export. Our savior option here is the Quality slide bar. Pull the slide bar to the file size value that one desires. Once other options are also in place, click Save and the JPEG would be reduced to the chosen file size.
References:
https://www.quora.com/How-do-you-reduce-the-size-of-a-JPEG-file-on-MAC
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