![]() JPEGmini compresses these well, but Google creates some nasty outlines around the edges of the circles ( image). 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 ( example). ![]() 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. The original image was just a photo taken on an 2014 Moto X. I redid the comparison with a little bit 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. 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! 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. 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. To make it easier to view the images side-by-side, here's an imgur album with each individual frame, which you can load it separate browser tabs and click back and forth:īelow, I've produced a table showing the different compression ratios. You can decide for yourself if there is any loss in visual acuity between the original, the Google-compressed, the JPEGmini-compressed, and the double-compressed image. This shows a comparison between the uncompressed image, Google's compression, JPEGmini's compression, and finally JPEGmini applied to an already Google-compressed image. So I a did a little test with a bright image to compare JPEGmini's compression with Google's compression. If you analyze the uncompressed and compressed images with a computer, you can see differences-but by eye, they look identical. Like JPEGmini, Google claims to be able to apply lossy compression to images without changing the perceptual quality of the image. The unlimited part comes with a caveat: Google will apply lossy compression to your files. Far as I can tell, its claims are pretty accurate, and it has literally helped me cut the size of some of my picture folders in half.Īs I'm sure most of you are aware, yesterday Google unveiled Google Photos, and with it announced unlimited storage space for photos and videos. ![]() Its compression of JPEGs is lossy, but it claims to do so leaving the perceptual image quality virtually unchanged. ![]() I've been using a program called JPEGmini for a couple years, now, to compress my JPEG images. It seems I'm a little late to the party discussing Google's new photo compression performance, but perhaps I have something to add. ![]()
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