Smjg

Image formats

Hi, thank you for uploading images to Commons. Here's a tip: Use the right image format for the kind of image. As a general rule, this is JPEG for photographs, and PNG for most other kinds of images. Using the wrong format can bloat the file size and/or degrade the quality of the image. Most modern graphics applications will give you the choice between these formats among others. Smjg (talk) 23:29, 1 February 2015 (UTC)

Yes, I'm working with an "old" Mac (sample Leopard system) & my Inkscape give images refused by Commons. I must change my computer & Inkscape first... when I will have the money ! ;-) Thank you, --Spiridon Ion Cepleanu (talk) 09:55, 2 February 2015 (UTC)

Thank you for the advices. I got the money, the new Mac is on the road ! With my webmaster, we will read your messages and install best applications. See you later, --Spiridon Ion Cepleanu (talk) 18:02, 8 June 2015 (UTC)

Overuse of {{Badjpeg}}

Hi. I think the intention of that template is for recently created files like diagrams, etc, generated by software, which may have been inadvertantly saved as JPEGs. There isn't much point in placing it on things like scans of very old documents which contain much paper and ink texture, etc, and are actually perfectly suitable for JPEG given high enough resolution. More importantly, most people uploading these don't have access to the actual physical document in the first place, and are simply uploading the JPEG file made available by the collection holder. There's no point in converting such a file to a non-JPEG format from a JPEG source. --Junkyardsparkle (talk) 20:11, 7 January 2016 (UTC)

What is the purpose of these images being on Commons – to show the paper and ink texture, or to show the content of the document? I would expect the latter - in which case there's no point in preserving the texture - indeed, it can sometimes detract from the content. As such, naturally it would be better to have a PNG file that is a good reproduction of the document. Moreover:

• Uploading such images as higher-resolution JPEGs isn't the answer, especially as they can still come out horrible when scaled down for display in articles. On the other hand, one who has access to a high-resolution JPEG source can scale it down to a suitable web resolution and at the same time save it as a PNG, thereby reducing further loss of quality due to scaling.
• {{Badjpeg}} isn't advocating converting it from the JPEG source. It leaves it up to contributors how to go about producing a version of the image in a lossless format. (Furthermore, even if it is an old document, it's possible that the image was uploaded by or can be traced back to somebody who has the original document and can rescan it and save it in a lossless format.)
• I've always held that the logistics of conversion aren't a criterion for using the template, but only the fact of the matter is. After all, the feasibility (or lack thereof) of performing the conversion seems to be often a matter of opinion or an assumption based on what tools one has or doesn't have.

Smjg (talk) 22:22, 9 January 2016 (UTC)

File:Henry Mayer, The Awakening, 1915 Cornell CUL PJM 1176 01 - Restoration.jpg not only does have a PNG version as well, but that Wikipedia's thumbnailer doesn't sharpen PNGs, so the PNG looks far worse in thumbnail. Compare!

JPEG (650px)

PNG (650px)

JPEG (300px)

PNG (300px)

Clearly, we need both a JPEG and a PNG for such images. PNG is the better file format - it allows the images to continue to be edited - but only JPEGs display properly in thumbnail. And, yes, I agree that's stupid. I've been asking Wikipedia to fix the display bug for years. They have no intention of doing so, and seem to consider it a feature. Adam Cuerden (talk) 02:04, 5 March 2016 (UTC)

Hmm. There must be some technical reason for the difference in how they scale. Moreover, in order to discover that a particular image scales better if it's a JPEG, somebody must have either saved and uploaded it as a JPEG out of ignorance, or converted it to a JPEG as a test. It seems to me that the answer is to scale the PNG down in a program that does a better job of it and upload the result, rather than turning it into a JPEG just so that it scales better. Smjg (talk) 19:30, 11 March 2016 (UTC)

PNG images

The thing you brand as {{Artifacts}} is actually anti-aliasing. Please, stop abusing tag templates. If you like to add (meta)data to file description pages, then categorize files. Incnis Mrsi (talk) 19:57, 24 October 2018 (UTC)

@Incnis Mrsi: Wrong – these images do have lossy compression artefacts. These artefacts are even more visible on the History of British film certificates page. (They have anti-aliasing as well, but that's irrelevant.) Smjg (talk) 12:47, 25 October 2018 (UTC)

It can be discussed case-by-case, but placing File:BBFC U 1970-1982.png and File:BBFC A 1970-1982.png into Images in lossless format with lossy compression artifacts defeats the purpose of the category as a cleanup category. These images doesn’t warrant cleanup because don’t feature anything distinctively JPEGgish – neither seen 1:1 nor as thumbnails. Incnis Mrsi (talk) 12:42, 2 November 2018 (UTC)

So why have you targeted these images in particular? Some of the other images in that category look less bad than these. Besides, this goes to show that artefacts being sufficiently significant is subjective, and as such you shouldn't untag them just because you personally disagree. Smjg (talk) 13:27, 2 November 2018 (UTC)

We don’t discuss general (technical) quality of PNGs, we discuss specifically artifacts from JPEG compression. Such image as File:BARC_logo.png is severely JPEGged and has an unreasonably large size, but doesn’t look really “bad”. Other images, e. g. File:BDMOT_on_ZMOT.png, have nothing to do with JPEG compression but look ugly. The difference is that the bulk of JPEG dirt (including Majora’s “masterpiece”) can be removed with such standard technique as posterizing, whereas fixing BDMOT_on_ZMOT.png requires something different. Incnis Mrsi (talk) 17:23, 2 November 2018 (UTC)

By the way, I’m unsure that the thing recently erased from BBFC_U_1970-1982.png was a “JPEG artifact” or something undesirable at all. It rather may be a genuinely visible detail existing due to typographic reproduction or some 20th-century technical processes. Incnis Mrsi (talk) 07:15, 3 November 2018 (UTC)

You got me there – maybe they aren't compression artefacts after all. But I'm not sure what you mean by "genuinely visible detail". On closer inspection, I have found that if they aren't compression artefacts then they must be artefacts of the scanning process. Smjg (talk) 10:49, 3 November 2018 (UTC)