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BPG Image format

bellard.org

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Re: BPG Image format

#172
post #157

Earlier quoted context omitted.

>It does not "beg" any questions. Yes it does. geofft wants to imply that it is somehow equivalent of using a nude of one's own mother, which is absurd. >Sexualizing women has nothing to do with ... Tell me why you think this one[1] is okay, as opposed to the Lena image; and what it has to do with whatever it is you do. [1] http://jeremykun.files.wordpress.com/2014/09/gala-dali.jpg?w...

Sure. This picture was painted by Dali, inspired by a Scientific American article about the minimum number of pixels needed to recognize an image. He was making an artistic statement that has a direct connection to Fourier analysis (and if you read the context article that image came from you might know this). This is a painting whose context is "fine art" (i.e. you can have tasteful nudity). That is a different cont…

>This picture was painted by Dali, inspired by a Scientific American article about the minimum number of pixels needed to recognize an image. He was making an artistic statement that has a direct connection to Fourier analysis

Blah blah blah blah blah blah blah blah... The Lena image contains a nice mixture of detail, flat regions, shading, and texture that do a good job of testing various image processing algorithms. It is a good test image. It is used by thousands of researchers in the field since image processing was a field.

So, your image isn't "sexualization" because Dali and "fine art" ?

>You clearly do not understand how the context of an image matters in interpreting it.

You cannot articulate a difference between Lena and the Dali that doesn't rely upon subjective opinion.

Re: BPG Image format

#173

Earlier quoted context omitted.

> Unless you want to deny a woman the right to permit Not doing something you are permitted to do is somehow denying their right to permit? It's nice of her permitting the use, however her permission doesn't force us to use it. By the same logic, it would be perfectly okay use goatse image if the guy permitted it, right?

By the same logic, it would be perfectly okay use goatse image if the guy permitted it, right? If the ability to represent the goatse image were a critical part of the evaluation process for a compression algorithm, then yes. However, we evolved to recognize and respond to subtle features in human faces, not human colons. So, no, goatse would not be an appropriate reference image.

If her face is the only face that is critical to the image compression analysis, yes, you are completely right.

I have a hard time understanding the knee jerk reaction to the change and the willingness to maintain the status quo. We have nothing to lose if the image is swapped with one that is less ostracizing --which is something Mozilla did in the past. Why defend it?

Re: BPG Image format

#174

Looking at the Lena pictures demo, the extremely low file size comparison at the top shows just how good .bpg is in that use case. That could make for some much lighter websites when used for less important items like image thumbnails on shopping sites, for example. When the file size gets larger at the end, it looks like there might be a little loss of detail. Ideally I'd like to compare them by switching back and f…

PrintScreen should let you do it, I suppose?

Re: BPG Image format

#175
post #36
post #21

Earlier quoted context omitted.

Well you can think of it as a tag name limited to 4 ascii characters if you like.

Yes, that makes it even stranger. Why use an unsigned 4-byte integer when tags are mapped to a number internally. Unless they anticipate to map more than 2^8-1 or 2^16-1 different tags. Maybe I'm reading it wrong. extension_tag ue7(32) ... 'extension_tag' is the extension tag. The following values are defined: 1: EXIF data. PS. I think I understand now. It's just meant as a shortcut. Not sure why this is done when EX…

Seems like EXIF data was originally to be included as part of the base spec (see dangling reference to exif_present_flag).

Re: BPG Image format

#176
post #62

Earlier quoted context omitted.

There's a difference between using a picture of a human face because we've determined it's useful for the test at hand, and using a 1970s Playboy scan because that was the most convenient thing for early computer-graphics researchers in the 1970s. In particular, the (appropriately-licensed) Kodak image set used in the Mozilla study includes multiple pictures of women, none of which are Playboy scans. The complaint is…

So the only real contention people have here is the source publication of the original image, right? Because AFAICT, the cropped image (as it's always been used in practice) is nor more or less offensive that kodim04.png from the kodak set. Furthermore, why does the licensing matter? Near as I can tell every use of Lena, except for by a for-profit company, constitutes fair use. The image, every time I've seen it, has…

I find the argument that there would be a lack of high-quality images in 1973 utterly unconvincing. Life magazine or national geographic could have been used. It was just a historical accident, and contrary to what you claim, I do not believe there is a pressing reason to keep using the exact same image, it's merely a relatively unquestioned tradition.

Re: BPG Image format

#177
post #148

The big story here is this introduces a new image file format without requiring you to upgrade a browser or download a plugin . Those aren't PNGs of representative images you're looking at - that's BPG decoding happening in your browser. So we don't like HVEC due to patent worries? Fine, we can swap in another format and use the same technique. We don't have an I-frame format for Daala that's finalized yet? Fine, we…

Polyfills have been around for a while; this isn't the first one. e.g. http://webpjs.appspot.com/ http://badassjs.com/post/12035631618/broadway-an-h-264-decod...

Re: BPG Image format

#178

Earlier quoted context omitted.

Progressive rendering of HEVC is not possible in the same way as it is done for JPEG or PNG. It is also not very suited to GPU rendering. A C++ decoder with assembly optimizations could easily run four times as fast as the Javascript version. Unfortunately distributing it would not be possible due to patents.

Why would a C++ version have to worry about patents but the JS one does not?

They both have to worry, just a different person. For JS, it is the page author / publisher. For C++, it would be the browser vendor.

Re: BPG Image format

#180
post #26
post #10

Earlier quoted context omitted.

"Most devices already include or will include hardware HEVC support, so we suggest to use it if patents are an issue." I don't know if that suggestion makes much sense, but you missed it in your quote.

Unless they changed their ways since h.264, it's probably a non-commercial license, even for tools or devices that suggest otherwise - like Final Cut Pro ( http://bemasc.net/wordpress/2010/02/02/no-you-cant-do-that-w... )

You can actually use HEVC for your content for free, even commercially.

Royalties only get involved when distributing encoders & decoders.

See page 7 here http://www.mpegla.com/main/programs/HEVC/Documents/HEVCweb.p...

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