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WebP is so great except it's not (2021)

eng.aurelienpierre.com

211–220 of 411 posts

Re: WebP is so great except it's not (2021)

#211
post #45
post #29

Earlier quoted context omitted.

It's not, it's just that people who spend thousands of dollars and hours into photography are more susceptible to care. Same with music, most people are fine with $15 earphones while musicians or music enthusiasts will find them disgusting.

Music is probably a bad example of your point, as that field is famous for audiophiles insisting they can hear a difference for various things only for them not being able to tell the difference in a double blind test.

Just because there are some 'extreme' weirdos in the audiophile space, doesn't mean that there is no difference between cheap and expensive equipment.

While people might not be able to tell the difference between $50 and $5000 speaker cables, anybody will be able to the hear the difference between $50 and $5000 speakers.

Re: WebP is so great except it's not (2021)

#212
post #4

I opened the first two pictures in separate tabs and switched quickly between them. There is zero difference. Tried it on two different monitors, Chrome and Firefox. Same with the pictures of the guy at the end. EDIT: The last comparison is webp twice, he linked it wrong. Here is the jpg one, still no difference: https://eng.aurelienpierre.com/wp-content/uploads/sites/8/20...

At 50 y/o my eyesight began to fail and yet the differences in the pictures are freaking obvious. As in: it's impossible to not see how huge the differences are. And many people commented the same. These simply aren't small differences. People who cannot see the differences or who only see them after taking a close look should realize something: there are many people for whom the differences are going to be immediate…

> People who cannot see the differences or who only see them after taking a close look should realize something: there are many people for whom the differences are going to be immediately obvious.

That's one possible conclusion. Another is that some people are overstating how obvious it is. I don't mean this as an insult - there's plenty of cases where people's stated perceptions and preferences disappear when tested under strict conditions (hello Audiophiles).

So - it's not immediately obvious whether claims such as yours are trustworthy.

(for the record I can see the difference but it's fairly subtle on my screen)

Re: WebP is so great except it's not (2021)

#213

I've noticed the same issue with WebP and have gone back to JPG/PNG for most things (jpg for photos, png for UI-type images) I think the real problem is, like many of the commenters here, most people can't tell the difference because desktop monitors have been stuck in a deadzone of zero innovation for the last 10 years. I'm sure half the folks here are viewing his example images on a 2012-era HD 1920x1080 LCD, which…

> I've noticed the same issue with WebP and have gone back to JPG/PNG for most things (jpg for photos, png for UI-type images)

Wait... I agree for JPG but if you use lossless WEBP instead of PNG, isn't it simply the same pixels, just with a file about 30% smaller than the corresponding PNG file? (and 15% smaller compared to already heavily optimized PNG files like when using zopfli/optipng/etc.).

Isn't the "lossless" in "lossless WEBP" actually lossless when converting a PNG file to WEBP?

FWIW when you convert losslessly a PNG to WEBP, then decompress the WEBP back to a PNG file, then convert again that PNG back to a WEBP file, you get the exact same lossless WEBP file. It's also the same WEBP you get when you encode losslessly from either a PNG or that same PNG but "crushed" with a PNG optimizer.

Re: WebP is so great except it's not (2021)

#214
post #4

I opened the first two pictures in separate tabs and switched quickly between them. There is zero difference. Tried it on two different monitors, Chrome and Firefox. Same with the pictures of the guy at the end. EDIT: The last comparison is webp twice, he linked it wrong. Here is the jpg one, still no difference: https://eng.aurelienpierre.com/wp-content/uploads/sites/8/20...

If I view the full images of the first two in two Chrome tabs, two Firefox tabs, or download them and open then both in Preview on a 27" 5k iMac and flip back and forth between the two I see nothing changing.

There is definitely something changing though, because if I open each in Preview, switch Preview to full screen, set the view to be actual size, and take a full screen screenshot, the screenshot for the WebP image is 14% smaller than the one for the JPEG.

If I use screen zoom to go way in and then flip between the two images I can finally see some changes. The JPEG background has more small scale variation in shade. In the hair there are some white streaks that aren't quite as long in the WebP. Lots of small changes in the shirt, but it is about 50/50 whether or not any given difference there looks better in the JPEG or the WebP.

Re: WebP is so great except it's not (2021)

#215
post #4

I opened the first two pictures in separate tabs and switched quickly between them. There is zero difference. Tried it on two different monitors, Chrome and Firefox. Same with the pictures of the guy at the end. EDIT: The last comparison is webp twice, he linked it wrong. Here is the jpg one, still no difference: https://eng.aurelienpierre.com/wp-content/uploads/sites/8/20...

There's a clear difference between the JPEG and WEBP versions. Especially on the background on the right of the man.

There are clear bands of various shades of grey that circle out of the brighter areas behind the face and from the mid-right edge. They appear to join about two thirds from the middle to the right edge. That artifacting is most notable at full size, but is still visible on the smaller size on the web page.

Re: WebP is so great except it's not (2021)

#216
post #4

I opened the first two pictures in separate tabs and switched quickly between them. There is zero difference. Tried it on two different monitors, Chrome and Firefox. Same with the pictures of the guy at the end. EDIT: The last comparison is webp twice, he linked it wrong. Here is the jpg one, still no difference: https://eng.aurelienpierre.com/wp-content/uploads/sites/8/20...

Lots of replies here saying either: "I can't see the difference" or "Wow the difference is stark".

My takeaway as a non-photographer is: "different tools for different uses". If you're posting photography where image quality matters then use JPEG or another format that you think displays the image best. If you're writing a blog post with screenshots or other images where minute quality doesn't matter that much then use WebP.

Re: WebP is so great except it's not (2021)

#217
post #157

The simple truth is that JPEG is more than good enough and has ubiquitous support. There is no reason to switch to a different format and risk degradation or reduced interoperability for slightly smaller file sizes.

I don't understand fanatically chasing smaller image sizes when JPEG was good enough for the web of the 90's. There must be a different reason to throw some of the highest paid engineers in the world at WebP and it ain't generosity.

Images on the web of the 90s were also low-res and generally didn't look very good.

Re: WebP is so great except it's not (2021)

#219
post #166
post #151

Earlier quoted context omitted.

For starters, anyone that ever worked with a codec, will know that you don't compare them with ONE SINNGLE IMAGE. This whole basic idea of the blog post is just to generate more whining and clicks and not to actually make a comparison between formats that's worth a basic smell test.

This cuts against WebP more: all of Google’s marketing was “it’s a third smaller!!!!” and then when you looked they were comparing it to unoptimized libjpeg outout and using computational metrics like SSIM which only crudely approximate what humans notice about image quality. I did the same comparison the author did when WebP came out but used an optimized JPEG encoder and found the same conclusion: when you produced…

In what way does "anything cut" against anything when you do cherry picked single datum point comparison?

There isn't a codec pair in this world where you can't make a cherry picked comparison where one of them is worse (I've done plenty of those).

Re: WebP is so great except it's not (2021)

#220
post #149

Earlier quoted context omitted.

As I work with codecs I've been following the situation quite closely and the attention to XL was pretty much zero until Google decided to not support it. Moreover, this whole topic is about a comparison over a SINGLE IMAGE. Anyone who ever came close to codecs would immediately dismiss this as ridiculous. Yet here we are.

I will respond to you since you posted about this so called "SINGLE IMAGE" three times in this post already. Ackchually, the blog post contains a comparison over TWO IMAGEs. But since you work with codecs, surely you understand that the blog post is complaining about how WebP interacts with gradients in general and not just about the specific images in the blog post. JXL was getting plenty of attention before the Chr…

To make a conclusion about how a codec handles image features you need to to quantitative comparison across a big enough data set to make conclusions about any kind of generalized quality.

This goes triple for modern codecs like JPEG XL, VP8/9, AV1/AVIF, etc. because they deliberately make tradeoffs when compressing based on how the image will SEEM to people, not how pixel correct it is. Note just how many people say they barely notice a problem - this is where WebP made the tradeoff. JPEG did it elsewhere (e.g. text).

Cherry-picking a single image is useful only for fanboy screeching.

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