Metal artifact correction and noise-adjustment of CT scan image

A device for correcting a CT scan image, the device comprising:

• a processor configured to execute machine readable instructions corresponding to a control logic for correcting a CT scan image stored on a storage medium, wherein the machine readable instructions, when executed by the processor, cause the processor to:
• extract a target image including a target region to be corrected from an original CT scan image;
• obtain a target projection range corresponding to the target region by orthographically projecting the target image, and correct target projection data within the target projection range to obtain corrected target projection data;
• generate noise-adjusted target projection data by adjusting noise of the corrected target projection data according to target projection data of an intensity domain which is obtained from target projection data of an attenuation domain, so as to generate noise-adjusted target projection data to improve noise consistency between the target region and rest of the CT original scan image;
• and
• reconstruct a corrected CT scan image based on the noise-adjusted target projection data
• wherein when adjusting noise of the corrected target projection data to generate the noise-adjusted target projection data, said machine readable instructions further cause the processor to:
• convert the target projection data of the attenuation domain into the target projection data of the intensity domain;
• multiply the target projection data of the intensity domain by a default transform coefficient so as to obtain transformed target projection data;
• use the transformed target projection data as a Poisson parameter to calculate a Poisson random number, and determine update transformed target projection data based on the Poisson random number;
• transform the update converted target projection data to update target projection data of the intensity domain;
• convert the update target projection data of the intensity domain into update target projection data of the attenuation domain;
• and
• determine the update target projection data of the attenuation domain as the noise-adjusted target projection data.