11–20 of 27 posts
Unfortunately, webp claims to have same image quality with smaller file size, but the 'real world analysis' compares images quality at the same file size. Further, image quality is measured in terms of mean RGB or value difference, which is very technical and does not matter to the human eye (a lot). For example, in the portrait, the last picture, the JPEG artifacts in the person's face really hurt more than the blur…
If they somehow managed to chop file sizes by 90% or more, it would have a small chance (it still wouldn't be guaranteed, as in the era of CDNs and caching and large pipes, static images just aren't a big concern). Instead they've marginally chopped file sizes in only certain scenarios, while adding numerous new downsides, while actually reducing the feature set.
Are they insane? I'm surprised they actually announced this.
Like MP3, JPEG is good enough unless the improvement of a replacement format is overwhelming. It doesn't have the political baggage of something like h264, so that argument doesn't apply.
More interesting than this silliness from Google are formats that actually bring new and impressive features. I recall that JPEG2000 could do incremental, stallable loading (or maybe I'm thinking of something else), such that as you scaled an image it wasn't loading an entirely new image, but instead was loading incrementally more data to provide the detail for that level. IP stopped it from taking off, but that was actually interesting. This isn't.
Another way to accomplish a similar effect without requiring a new file format would be to apply a selective gaussian blur (or another de-artifacting filter) to highly compressed jpegs before displaying them.
Of course, no one does that because the trade-off is generally not considered to be a good one.
Earlier quoted context omitted.
That's fine, I agree. My point was not "His metric is the most awesome, shut up", it was "Despite only giving one kind of number, the author still included other analysis and subjective opinion in the writeup for each photo, so it's not as bad as you're trying to imply".
You asked How else would you construct an objective test? And my answer is, just make sure you're being fair in measuring the same thing the encoders are optimising for.
Unfortunately, webp claims to have same image quality with smaller file size, but the 'real world analysis' compares images quality at the same file size. Further, image quality is measured in terms of mean RGB or value difference, which is very technical and does not matter to the human eye (a lot). For example, in the portrait, the last picture, the JPEG artifacts in the person's face really hurt more than the blur…
1. How else would you construct an objective test? Creating images of the same quality and then comparing their file sizes seems prohibitively difficult if not impossible. This test, otoh, implies the same information (minus the exact difference in file size), but is pretty easy to set up. 2. Those were the reported numbers, but it's not like that was the only data point discussed in the article. Every single photo h…
Besides, I don't see why you need megabytes of photo data, regular internet photo data would have sufficed (for which the authors say they have developed webp anyways).
I agree with your point that he included subjective evaluation, though.
Those who don't learn from history are doomed to repeat it. This is a futile effort by Google and will go no where. If they somehow managed to chop file sizes by 90% or more, it would have a small chance (it still wouldn't be guaranteed, as in the era of CDNs and caching and large pipes, static images just aren't a big concern). Instead they've marginally chopped file sizes in only certain scenarios, while adding num…
In the meantime, if early adopters get a slightly better web experience -- that's a win for Google. They want more marginal pressure to upgrade.
Those who don't learn from history are doomed to repeat it. This is a futile effort by Google and will go no where. If they somehow managed to chop file sizes by 90% or more, it would have a small chance (it still wouldn't be guaranteed, as in the era of CDNs and caching and large pipes, static images just aren't a big concern). Instead they've marginally chopped file sizes in only certain scenarios, while adding num…
Unfortunately, webp claims to have same image quality with smaller file size, but the 'real world analysis' compares images quality at the same file size. Further, image quality is measured in terms of mean RGB or value difference, which is very technical and does not matter to the human eye (a lot). For example, in the portrait, the last picture, the JPEG artifacts in the person's face really hurt more than the blur…
