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Show HN: Jpeg.io – Convert any major image format into a highly optimized JPEG

jpeg.io

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Re: Show HN: Jpeg.io – Convert any major image format into a highly optimized JPEG

#71

How do jpeg.io's proprietery JPEG optimization algorithms perform compared to JPEG2000, webp or re-jpeg ?

Probably well against JPEG2000, which isn't actually that good. Wavelets look bad when compressed because they blur so much.

JPEG will have a really hard time competing against WebP, x264 --tune stillimage, or HEVC. Nobody uses those though.

Re: Show HN: Jpeg.io – Convert any major image format into a highly optimized JPEG

#72
post #15

Did a quick comparison test with this beautiful piece of artwork I just created. original http://i.pi.gy/0K7d.png (2.1 MB) jpeg.io http://i.pi.gy/AP8v.jpg (102 KB) Photoshop 60% jpeg Export http://i.pi.gy/Wr4P.jpg (90 KB) tinypng.com http://i.pi.gy/ndKA.png (74 KB) Note pi.gy does not compress uploads.

For fun, I took your original PNG from http://i.pi.gy/0K7d.png (205.5KB), converted it to maximum-quality JPEG (with Preview in OSX), then compressed it with JPEG Mini, resulting in a 122.6KB file.

ImageOptim was able to shave off an extra 10KB with no visible loss.

The resulting image at 112.2KB: https://i.imgur.com/kzZzfIi.jpg

Re: Show HN: Jpeg.io – Convert any major image format into a highly optimized JPEG

#76

Earlier quoted context omitted.

Are you serious? A digital photo translated to PNG is going to be quite large. PNG has it's place, for sure, but it doesn't compress photographs like JPEG does. PNG is great for line art, solid color vector that has been rasterized, etc. JPG is great for photos.

>Are you serious? Perfectly. I'm not very familiar with image compression and JPEG conjures up images of pixellated atrocities. It seems like either progress has been made in this domain or most JPEG encoders on the internet are poorly configured (in which case the present webapp makes sense).

Perhaps if you were, I don't know, the biggest photography site on the internet:

https://www.flickr.com/

(Or one of the others: https://500px.com/photo/20852455/-by-maxim-gurtovoy https://1x.com/)

JPEG is used for any type of complex image as PNG compression can't compare.

Re: Show HN: Jpeg.io – Convert any major image format into a highly optimized JPEG

#77
post #19
post #15

Did a quick comparison test with this beautiful piece of artwork I just created. original http://i.pi.gy/0K7d.png (2.1 MB) jpeg.io http://i.pi.gy/AP8v.jpg (102 KB) Photoshop 60% jpeg Export http://i.pi.gy/Wr4P.jpg (90 KB) tinypng.com http://i.pi.gy/ndKA.png (74 KB) Note pi.gy does not compress uploads.

Since he doesn't summarize the test above, let me. The jpeg.io result is bigger than the other two and noticeably worse quality. The problems were with the sharp lines. Perhaps jpeg.io specializes in photo-realistic pictures rather than graphics and logos.

Would it be worthwhile to compress the edges separately? I.e., use edge-detection + dilation + quantize + mask to get the edges, then compress that less aggressively, and overlay over the aggressively-compressed image?

Re: Show HN: Jpeg.io – Convert any major image format into a highly optimized JPEG

#78

Has anybody tried mozjpeg? https://github.com/mozilla/mozjpeg It works much better than any of the alternatives listed here, I'm surprised noone mentioned it yet. Here is an image compressed to the same size with mozjpeg http://m8y.org/hn/12597098.jpeg jpeg.io http://i.pi.gy/AP8v.jpg

If you need to do one-off Mozjpeg compressions, I highly recommend imageoptim's online compressor, which you can find here:

https://imageoptim.com/mozjpeg

It has sensible defaults and is super-easy to use.

Re: Show HN: Jpeg.io – Convert any major image format into a highly optimized JPEG

#79

Earlier quoted context omitted.

Can you elaborate on your comment? I'm genuinely curious. :)

When people were devising ways to transmit television signals they had only limited available bandwidth, and since everything was analog compression wasn't feasible. So they did everything they could to minimize the information that needed to be transmitted. They interlaced the signal, so every frame only had half as much pixels. They also split the signal in chroma and luma (basically colour and brightness, respecti…

> They also split the signal in chroma and luma (basically colour and brightness, respectively) and then lowered the resolution of the chroma with the justification that the human eye is far more sensitive to differences in brightness than differences in colour.

It's worth mentioning that the split between chroma and luma wasn't for "compression" but so color signals were backwards compatible with black and white televisions. It's also why we use 29.97 fps instead of 30.[0]

[0]: http://glydeck.blogspot.com/2011/07/why-do-we-have-2997-fram...

Re: Show HN: Jpeg.io – Convert any major image format into a highly optimized JPEG

#80
post #55

Earlier quoted context omitted.

jpeg.io may have lost on sharp lines, but it had WAY fewer artifacts than either of the other exports, and the blue was closer to the original compared to the Photoshop export. In my opinion, it's a better quality image.

Honest question: if I can't see the artifacts without zooming in, is there any reason why I should care? Of all the conversion results offered, the Photoshop export actually looks the best to my eyes, so I'm genuinely trying to understand why the jpeg.io result would be considered better quality in this particular case.

I don't need to zoom in or even look that hard to see the artifacts. Maybe that's me, or maybe that's the retina display on my MacBook, but that's why jpeg.io looks the best for me. If you can't see the artifacts though, I would say jpeg.io loses out.
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