![]() He has also shared his findings on Reddit.Since the update to iOS 14 you have problems using JPEG Jackal Lite? Or does JPEG Jackal Lite cause errors under iOS14? Then find out in this post what the issues with iOS14 have to do and what you can do about it. Until then, if you have some important images that you want to save from minor image artifacts, it might be prudent to keep an extra backup outside of Google Photos.Ībout the author: Brian Young is a photography enthusiast who’s interested in JPEG compression technologies. Given that Google has their own web browser and their own mobile OS, they’re more than capable of even pushing out new image formats or new standards. Nevertheless, I suspect that this is something Google will improve over time. Google’s beats JPEGmini in compression some of the time, but it looks like there are still some kinks to work out to prevent aberrations and other artifacts. Overall, I think Google and JPEGmini both have impressive algorithms. Other than that, both JPEGmini and Google crush the details in the gray background differently, and I suspect that it’s up to personal preference as to which one is better. JPEGmini compresses these well, but Google creates some nasty outlines around the edges of the circles. Take a look at the color wheels just to the right of the bottles at the bottom of the original image. That’s not necessarily a bad thing if Google can compress colors imperceptibly. Google, on the other hand, is altering the colors quite a bit. This means that JPEGmini isn’t altering the colors of the original image very much. JPEGmini’s difference maps are all nearly monochromatic. Taking a look at the difference maps, we can see that JPEGmini and Google compress the JPEGs a little bit differently. Google’s algorithm performs a little bit better, and we see that the best overall compression is still when you perform a Google compression first, and then a JPEGmini compression on top of it. This time the results are a little bit different, and there are some interesting results. Because Google only allows a max photo size of 16 megapixels and the original test image was 24 MP, I downloaded the RAW format shot and resized it down to 16 MP in Photoshop before starting the test. This time around, I used a studio test image taken by a Nikon D750 DSLR ($2000 camera) taken from DPReview. The original image was just a photo taken on an 2014 Moto X. Next, I redid the comparison with a slightly better image. No pain no gain, I guess, but even so, I think it exhibits remarkably little degradation consider it is nearly a 100% improvement over either Google or JPEGmini’s algorithms alone. The biggest jump in image quality degradation is from applying JPEGmini to an already Google-compressed image. JPEGmini’s compression is good, too, eeking out an extra 40% compression over Google’s while still causing relatively little damage to the original photo. The original, uncompressed image was only very slightly altered by Google’s method, and yet it still was able to nearly cut the filesize in half. What should be immediately clear is that Google’s compression algorithm was the least degrading by a long shot. Of course, the double-compressed image has the most notable degradation of image quality, but even so, it is so minor that, I think, it is still almost certainly unnoticeable in large photographs.įinally, for a more rigorous analysis of the actual differences between each of the four test cases (original, Google, JPEGmini, Google+JPEGmini), I loaded them up in Photoshop and used the difference layer effect to calculate the actual changes in the original image that the compression algorithms performed. Most remarkable of all, though, is that by combining the two–Google and then JPEGmini–it doubled the compression even of the already-compressed image! On the other hand, JPEGmini manages to eek out an extra 40% compression with only trivial image degradation. The reduction in image quality is almost imperceptible, yet it manages to nearly cut the file size in half. In my personal opinion, all four images have the same perceptual image quality. Below, I’ve produced a table showing the different compression ratios.
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