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What that's what progressive means... where do you select that, is that something you select in say GIMP? >Progressive JPEG images load from more blurry to les
by ge96 9y ago
What that's what progressive means... where do you select that, is that something you select in say GIMP?
>Progressive JPEG images load from more blurry to less blurry. The progressive option can easily be enabled in Pillow
What is Pillow, Python... hmm... so loading a small version spread out to full size with blur, then in the background loading full size copy to replace blurred small image, that is not progressive loading...?
If I was looking into progressive loading... and implemented a CDN... can this still work? Is it python specific? I use PHP for scripting... maybe an excuse to actually build something with Go rather than the hello world examples. (assuming you can use Go)
Edit: also is progressive loading something that happens once or does a script have to do that every time the photo is pulled?
What is this a support forum? haha calm down kid
- sp332 9y agoYes, it's one way of storing the image data in a single JPEG file. It doesn't need multiple files and it doesn't need any extra code. It's usually only visible when you're loading the file over a slow link. Old software might not show the intermediate steps from the file but they should still be able to display the image once it's 100% loaded.
- ge96 9y agoThis isn't the same as when you see a photo load with horizontal lines vertically usually top-to-bottom right?
- mysterydip 9y agoBack in the days of slow internet access, nearly every non-animated image was a jpg and loading from blurry to clear was the norm. It's part of the file format.
- mark-r 9y agoThe idea was that you'd see the image get progressively better as each pass was completed, thus the term "progressive". But in practice the browsers decided not to display anything until the image was finished loading anyway.
- sp332 9y agoI don't think this is right. IE9 renders progressive JPEGs progressively. https://calendar.perfplanet.com/2012/progressive-jpegs-a-new-best-practice/ https://calendar.perfplanet.com/2012/progressive-jpegs-a-new...
- mark-r 9y agoIt appears the situation isn't static, thanks for the link! It would have been interesting to see older versions of Chrome and Firefox tested too - I'm wondering now if my recollections are faulty.
- cpeterso 9y agoThis site simulates a slow download of a progressive JPEG so you can test how your browser renders them. The page is from 2007 so its claim that IE doesn't render them progressively appears to be out of date. http://pooyak.com/p/progjpeg/ http://pooyak.com/p/progjpeg/
- khedoros1 9y agoI clearly remember watching the image clarity crawling down photos on dial-up. Otherwise, you'd be staring at a blank screen for 2 minutes, instead of a gradually-improving image. (Since you mentioned Chrome and Firefox in another comment, I'm not thinking of browsers that new).
- jschwartzi 9y agoNetscape Navigator certainly did this. IE did too, I recall.
- masklinn 9y ago> What is Pillow A Python library for manipulating image, like ImageMagick and the like. > so loading a small version spread out to full size with blur, then in the background loading full size copy to replace blurred small image, that is not progressive loading…? Progressive JPEG is closer to refinement of previous blocks, it doesn't "add blur", it starts with smaller less precise blocks then refines them. Progressive jpeg actually tends to be smaller than non-progressive (as opposed to e.g. progressive PNG) > Edit: also is progressive loading something that happens once or does a script have to do that every time the photo is pulled? There is no script, progressive JPEG is part of the core spec.
- WhiteOwlLion 9y agoIf we had progressive JPEG for all JPEGs, low bandwidth networks could request a percentage of the file and save on total data needed to render a page. This could be useful for areas where 2G may be the norm.
- jharger 9y agoI remember some dial-up ISPs doing almost this a few years ago. A friend of mine lived in a rural area, and his dialup provider would show a low-res version of the image. If he clicked on the image, it would load the full version. I think that they would hijack the webpage and do their special image cache thing on a proxy server. It was a really weird experience, but also kind of cool.
- Negitivefrags 9y agoIn this age of devices with different DPI and pinch-to-zoom it would be nice if the browser would only get as many progressive levels as required for the current display resolution of the image.
- ge96 9y agoSorry I wasn't implying blur was a part of progressive loading. I kept hearing about progressive loading but didn't understand what it was. I used the blur-up method, low res small file blurred, replace with high res full version without blur. Thanks for the info. Is it right to assume any photo with a .jpg extension does this by default? I'll go hit the links.
- pyre 9y agoPillow is a fork of PIL -- the Python Imaging Library -- which had become unmaintained ('PIL' is in 'pillow'). It's the go-to image manipulation library on Python.