What is an artifact in computer graphics?

Answer 1

In computer graphics, artifacts are visual anomalies, unwanted blemishes on the screen, or errors produced by image compression or manipulation.

Sometimes malware produces visual artifacts. For instance, one spyware application produced a green dot in the upper left hand corner of the screen. Maybe its writer added that during development to trace whether it was installed on the test computers or not and forgot to remove it.

Computer games are notorious for showing image artifacts. The Hall of Mirrors Effect ("HOM effect") is often produced in no-clipping mode in first person shooter games, when the player is out of bounds, or the vertices in the game map are open due to a design flaw. So you might see several images stacked together and some white flashes as you move the character. In the early days of computer games, Sprite collisions and player-missile collisions were common. It was common in Breakout to have several of the balls on the screen, though often with parts missing or for the paddle the player moves to show damage.

If you convert something to JPG, you often get a loss of quality and some bit of a haze around parts of the image. This problem is most evident around text and faces. This pattern of distortion is usually similar in every image that is compressed using JPEG. That is known as Huffman noise.

In digital Photography, artifacts are areas of distortion or missing parts of an image that are specific to the exact camera used. Cameras use a CCD chip, and unfortunately, the chips are often produced with defects. So as you take photos, the same pixels will be missing in every photo and act like a fingerprint. So if someone uses a digital camera to help commit a crime, perhaps extortion, it is possible to trace the images to the camera.

Answer 2

In computer graphics, artifacts are visual anomalies, unwanted blemishes on the screen, or errors produced by image compression or manipulation.

Sometimes malware produces visual artifacts. For instance, one spyware application produced a green dot in the upper left hand corner of the screen. Maybe its writer added that to trace whether it was installed on the test computers or not and forgot to remove it.

Computer games are notorious for showing image artifacts. The Hall of Mirrors Effect ("HOM effect") is often produced in no-clipping mode, when the player is out of bounds, or the vertices in the game map are open due to a design flaw. So you might see several images stacked together and some white flashes as you move the character. In the early days of computer games, sprite collisions and "player-missile collisions" were common. It was common in Breakout to have several of the balls on the screen, though often with parts missing or for the paddle the player moves to show damage.

If you convert something to JPG, you often get a loss of quality and some bit of a haze around parts of the image, and the pattern is usually similar in every image that is compressed as JPG. That is known as Huffman noise.

In digital photography, artifacts are areas of distortion or missing parts of an image that are specific to the exact camera used. Cameras use a CCD chip, and unfortunately, the chips often come with defects. So you take photos and the same pixels are missing in every photo and act like a fingerprint. So if someone uses a digital camera in the commission of a crime (such as extortion), it is possible to trace the images to the camera.