Isn't there hardware support for JPEG decoding on most mobile devices?
If so, I imagine it couldn't compete performance and battery life wise.
I remember Mozilla did a software video decoder once in JavaScript.
Still, it is quite amazing.
Still, it is quite amazing.
This is the software video decoder, by the way: https://github.com/brion/ogv.js
If this is the case, then putting in a hardware decoder would be a needless expense.
I believe that some browsers actually keep in RAM all the images uncompressed, that can acually be the reason that makes the potential for optimizations less obvious.
Very large images are fairly rare on the web. In particular phones don't have giant displays, so it's usually a waste of bandwidth to send a huge picture to a phone as part of a webpage. And, speaking only for mobile Firefox at the time I worked on it, we had lots of bigger problems with large images than decoding speed. For example, Firefox would keep the whole decoded image in memory while it was onscreen, even if it was only displaying only part of the image or only a downsampled version of the image. If it's a giant image, the decoded image could use up a large fraction of the device's memory.
I'm also not aware of any major phones with have GPGPUs -- I'm not an expert in this stuff, but I think you'd need that to get any serious acceleration from JPEG decoding.
the demos reminded me what browsing on dialup was like. in fact dialup was better cause at least the decoding/loading was progressive/incremental, which doesnt seem to be the case here. i assume it's just the way the decoder is implemented?
Not quite production-ready, I think.
Safari/iOS and Chrome/Android worked with no issue. Desktop Firefox also worked.