Editing Talk:2414: Solar System Compression Artifacts

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:Re: "The Voyager image (and track) is overlaid at finer resolution", if it not unheard-of for a compression algorithm to render, say, 32x32 pixel blocks as if they were single, larger pixels if their immediate neighbors are almost the same shade, while rendering small, detailed, and high contrast portions of the image at a higher resolution. No "overlay" required. ''(Still unsigned!)''
 
:Re: "The Voyager image (and track) is overlaid at finer resolution", if it not unheard-of for a compression algorithm to render, say, 32x32 pixel blocks as if they were single, larger pixels if their immediate neighbors are almost the same shade, while rendering small, detailed, and high contrast portions of the image at a higher resolution. No "overlay" required. ''(Still unsigned!)''
 
::Within an area of finer details, artefacts ''would'' be seen as the "meh, this is just one block" attitude is changed to incorperate detail of interest within a sub-block. There's no sign of fringe-artefacts (other than normal XKCS antialiasing of lines against background). I'd say it was a "solar wind" low-detail layer over which is incorporated a "Voyager" standard-detail layer with transparency, not a single layer of subject-aware tunable blockwise compression. (It might have come out differently if the composition was saved in an actual lossy-compression, by Randall, rather than .png, but for different reasons. Bit that's a meta-discussion issue, not nerd-sniping.) [[Special:Contributions/141.101.104.241|141.101.104.241]] 01:18, 22 January 2021 (UTC)
 
::Within an area of finer details, artefacts ''would'' be seen as the "meh, this is just one block" attitude is changed to incorperate detail of interest within a sub-block. There's no sign of fringe-artefacts (other than normal XKCS antialiasing of lines against background). I'd say it was a "solar wind" low-detail layer over which is incorporated a "Voyager" standard-detail layer with transparency, not a single layer of subject-aware tunable blockwise compression. (It might have come out differently if the composition was saved in an actual lossy-compression, by Randall, rather than .png, but for different reasons. Bit that's a meta-discussion issue, not nerd-sniping.) [[Special:Contributions/141.101.104.241|141.101.104.241]] 01:18, 22 January 2021 (UTC)
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This doesn't just happen in old images. I still see this frequently when watching movies, even new ones, where what should be a smooth gradation of tones shows steps. The other obvious defect is poor sprite handling, which causes artifacts like someone's facial features not moving with their head movements.
 
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I'm not sure dithering would be a useful way to dispel the banding, since dithering would increase the compressed data size because you no longer have large areas of all-the-same-pixel-value.
 
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The banding could also be an artifact of the decompression. If you consider that a format like JPEG uses something like Fourier transforms it seems it should be able to represent a gradation easily and the stepped banding with difficulty, so I might be tempted to blame the banding on the decompression code.[[Special:Contributions/108.162.241.70|108.162.241.70]] 13:46, 22 January 2021 (UTC)
 
  
 
I did a 'best fit' on the probable solar system, across this 'map' (which I think is slightly made up, because of certain issues when I started differentiations of the grey-levels, making me think it has been 'painted', or enhanced, not taking from real data - of the 'real thing' or not). I don't seem to get any Wiki upload/new-media rights, as an IP user, but if anyone wants to look at the image saved at https://imgur.com/KSqC1Nr and consider it/be inspired by it then I offer it up, gratis.  It features the orbits of Earth, Mars, Jupiter, Saturn, Uranus and Neptune in body-appropriate hues, such that they are to scale with the true distance of Voyager from the focus of the likely circular orbts. (I think I left the 'Sun' pixel (image pixel, not 'artefact pixel') magenta, easier to see against the whitist-whiteout core shade.) I only refrained from adding Pluto (and Eris, etc) off because I don't have immediate into on the far more eccentric oval.  Darn, I meant to add the asteroid belt. As a suitably fuzzy grey band. Not redoing it. [[Special:Contributions/141.101.77.126|141.101.77.126]] 22:58, 24 January 2021 (UTC)
 
I did a 'best fit' on the probable solar system, across this 'map' (which I think is slightly made up, because of certain issues when I started differentiations of the grey-levels, making me think it has been 'painted', or enhanced, not taking from real data - of the 'real thing' or not). I don't seem to get any Wiki upload/new-media rights, as an IP user, but if anyone wants to look at the image saved at https://imgur.com/KSqC1Nr and consider it/be inspired by it then I offer it up, gratis.  It features the orbits of Earth, Mars, Jupiter, Saturn, Uranus and Neptune in body-appropriate hues, such that they are to scale with the true distance of Voyager from the focus of the likely circular orbts. (I think I left the 'Sun' pixel (image pixel, not 'artefact pixel') magenta, easier to see against the whitist-whiteout core shade.) I only refrained from adding Pluto (and Eris, etc) off because I don't have immediate into on the far more eccentric oval.  Darn, I meant to add the asteroid belt. As a suitably fuzzy grey band. Not redoing it. [[Special:Contributions/141.101.77.126|141.101.77.126]] 22:58, 24 January 2021 (UTC)

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