File:April 01-40N-2100-Fieldbook of Stars-025 - JPEG noise.png
Original file (2,272 × 2,492 pixels, file size: 493 KB, MIME type: image/png)
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Summary[edit]
DescriptionApril 01-40N-2100-Fieldbook of Stars-025 - JPEG noise.png |
English: A demonstration of the presence of JPG noise in a black and white image. Generation process (starting with sm.png and sm.jpg, which is saved from the PNG with quality=90):
convert sm.jpg sm.png -compose minus -composite -negate -threshold 99% -fill red -opaque black -transparent white diff.png convert sm.png result.png -composite out.png |
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Date | 1907, edited 2021 | |||||
Source | File:April 01-40N-2100-Fieldbook of Stars-025.jpg | |||||
Author | William Tyler Olcott | |||||
Permission (Reusing this file) |
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Other versions | Version without highlighted noise: File:April 01-40N-2100-Fieldbook of Stars-025.jpg |
File history
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Date/Time | Thumbnail | Dimensions | User | Comment | |
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current | 17:34, 10 February 2021 | 2,272 × 2,492 (493 KB) | Inductiveload (talk | contribs) | {{Information |Description={{en|1=A demonstration of the presence of JPG noise in a black and white image. Generation process (starting with sm.png and sm.jpg, which is saved from the PNG): <pre> convert sm.jpg sm.png -compose minus -composite -negate -threshold 99% -fill red -opaque black -transparent white diff.png convert sm.png result.png -composite out.png </pre> }} |Source=File:April 01-40N-2100-Fieldbook of Stars-025.jpg |Date=1907, edited 2021 |Author=William Tyler Olcott |Per... |
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Horizontal resolution | 118.11 dpc |
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Vertical resolution | 118.11 dpc |
File change date and time | 17:29, 10 February 2021 |