JPEG_artifacts are a type of compression artifact.
They are prevalent in images uploaded on Twitter and Facebook.
These can be either blockiness or mosquito noise and are usually seen in areas with high contrast, such as near lines. If in doubt, refer to some of the images with this tag.
This tag should be used for images where these artifacts are noticeable when viewed normally. Uploading images with visible artifacts should be avoided.
Use Google's reverse image search feature or iqdb to possibly find a higher quality version.
Details 
Edit
Examples:
- The thumbnail for a video which was uploaded in July 1, 2008 has JPEG artifacts.[1]
- There is an image of Bob from Bob the Builder with a Star of David on his helmet; the image is named "Bob the Zionist Builder", and it has JPEG artifacts.[2]
- At the bottom of a help page examples of JPEG artifacts are available which match the following descriptions: "No noticeable compression", "Light Compression", "Heavy Compression", and "Ms Paint compression"; the page is lacking an example for "very heavy compression".[3]
Trivia Edit
The following (minus the first and second line) is all of the text from "Remove jpgartifacts from manga PS CS6 keyboard batch robot-mbpELEX5.txt", downloaded from http://pastebin.com/mbpELEX5 (a paste which has been removed):== Remove jpgartifacts from manga PS CS6 keyboard batch robot-mbpELEX5.txt ==
*Works on 1366x768 px. screen
[General]
Name=remove_jpeg_artifacts_from_manga
StartKey=<F10>
EndKey=<F11>
Description=
Enable=1
RepeatOption=0
RepeatTimes=31
OriginalSpeed=1
UseSimilarWin=0
UseRecWin=1
[Script]
Comment: ==== Start recorded actions ====
MouseMove(556, 385)
WAIT(140)=> [remove on faster speed]
MouseMove(554, 385)=> [remove on faster speed]
MouseMove(547, 383)=> [remove on faster speed]
MouseMove(451, 308)=> [remove on faster speed]
MouseMove(362, 218)=> [remove on faster speed]
MouseMove(209, 68)=> [remove on faster speed]
MouseMove(174, 30)
WAIT(130)=> [remove on faster speed]
MouseMove(135, 0)=> [remove on faster speed]
MouseMove(132, 0)=> [remove on faster speed]
MouseMove(128, 0)=> [remove on faster speed]
MouseMove(120, 0)=> [remove on faster speed]
MouseMove(112, 1)=> [remove on faster speed]
MouseMove(109, 3)=> [remove on faster speed]
MouseMove(105, 4)
WAIT(130)=> [remove on faster speed]
MouseMove(109, 4)=> [remove on faster speed]
MouseMove(125, 4)=> [remove on faster speed]
MouseMove(144, 4)=> [remove on faster speed]
MouseMove(193, 5)=> [remove on faster speed]
MouseMove(220, 9)=> [remove on faster speed]
MouseMove(228, 10)=> [remove on faster speed]
MouseMove(246, 13)=> [remove on faster speed]
MouseMove(251, 14)=> [remove on faster speed]
MouseMove(254, 14)=> [remove on faster speed]
MouseMove(263, 17)=> [remove on faster speed]
MouseMove(270, 17)=> [remove on faster speed]
MouseMove(275, 17)=> [remove on faster speed]
MouseMove(281, 18)
WAIT(78)
MouseDown("left")
KeyUp("","","","<Space>", 1)
MouseUp("left")
WAIT(180)
MouseMove(281, 20)
MouseMove(281, 32)=> [remove on faster speed]
MouseMove(287, 64)=> [remove on faster speed]
MouseMove(288, 72)=> [remove on faster speed]
MouseMove(291, 94)=> [remove on faster speed]
MouseMove(292, 111)=> [remove on faster speed]
MouseMove(292, 113)=> [remove on faster speed]
MouseMove(292, 115)=> [remove on faster speed]
MouseMove(292, 116)=> [remove on faster speed]
MouseMove(292, 117)=> [remove on faster speed]
MouseMove(292, 118)=> [remove on faster speed]
MouseMove(292, 122)=> [remove on faster speed]
MouseMove(292, 125)=> [remove on faster speed]
MouseMove(292, 132)=> [remove on faster speed]
MouseMove(292, 136)=> [remove on faster speed]
MouseMove(292, 143)=> [remove on faster speed]
MouseMove(292, 157)=> [remove on faster speed]
MouseMove(292, 163)=> [remove on faster speed]
MouseMove(292, 177)=> [remove on faster speed]
MouseMove(292, 180)=> [remove on faster speed]
MouseMove(292, 181)
WAIT(800)
MouseDown("left")
MouseUp("left")
WAIT(6521)
KeyDown("","","","<Enter>", 1)
WAIT(546)
KeyUp("","","","<Enter>", 1)
WAIT(2371)
KeyDown("","","","<Shift>", 1)
WAIT(203)=> [remove on faster speed]
KeyDown("","","","<F5>", 1)
WAIT(328)
KeyUp("","","","<F5>", 1)
KeyUp("","","","<Shift>", 1)
WAIT(1217)
KeyDown("","","","<Enter>", 1)
WAIT(265)
KeyUp("","","","<Enter>", 1)
WAIT(2715)
KeyDown("","","","<Ctrl>", 1)
KeyDown("","","","S", 1)
WAIT(453)
KeyUp("","","","S", 1)
KeyUp("","","","<Ctrl>", 1)
WAIT(1950)
KeyDown("","","","<Up>", 1)
KeyUp("","","","<Up>", 1)
KeyDown("","","","<Up>", 1)
KeyUp("","","","<Up>", 1)
KeyDown("","","","<Up>", 1)
KeyUp("","","","<Up>", 1)
WAIT(234)=> [remove on faster speed]
KeyDown("","","","<Enter>", 1)
WAIT(437)
KeyUp("","","","<Enter>", 1)
WAIT(1498)
KeyDown("","","","<Ctrl>", 1)
KeyDown("","","","W", 1)
WAIT(266)
KeyUp("","","","W", 1)
KeyUp("","","","<Ctrl>", 1)
WAIT(936)
MouseMove(300, 188)
MouseMove(351, 227)=> [remove on faster speed]
MouseMove(419, 276)=> [remove on faster speed]
MouseMove(538, 354)=> [remove on faster speed]
MouseMove(564, 374)=> [remove on faster speed]
MouseMove(581, 386)=> [remove on faster speed]
MouseMove(599, 399)=> [remove on faster speed]
MouseMove(605, 404)=> [remove on faster speed]
MouseMove(609, 406)=> [remove on faster speed]
MouseMove(611, 407)=> [remove on faster speed]
MouseMove(611, 405)=> [remove on faster speed]
MouseMove(611, 403)=> [remove on faster speed]
MouseMove(609, 397)=> [remove on faster speed]
MouseMove(608, 393)=> [remove on faster speed]
MouseMove(607, 391)=> [remove on faster speed]
MouseMove(606, 389)=> [remove on faster speed]
MouseMove(605, 386)=> [remove on faster speed]
Comment: ==== End of recorded actions ====
See also Edit
References Edit
- ↑ https://www.youtube.com/watch?v=0Q2D-53HfIk - title: "What Is A Nationalist?"; uploaded: July 1, 2008; very heavily compressed thumbnail: https://i.ytimg.com/vi/0Q2D-53HfIk/hqdefault.jpg;
- ↑ http://www.preoccupiedterritory.com/wp-content/uploads/2016/05/Bob-the-Zionist-Builder.png
- ↑ http://gelbooru.com/index.php?page=help&topic=post - archive: http://web.archive.org/web/20160525222658/http://gelbooru.com/index.php?page=help&topic=post;
This tag is aliased from jpeg_artefacts, jpg_artifacts, and jpegartifacts.
