便携式X射线成像仪图像非均匀性分析及校正

详细信息

Analysis and Correction for Image Nonuniformity of Portable X Radiography Instrument

摘要: 分析了图像非均匀性产生机理，建立了成像仪每个像元通道光电响应的数学模型，提出了非均匀性的多点线性拟合校正算法，对比了校正前后的图像及标准差。结果表明，非均匀性校正方法适用于像元输出值与管电流呈线性关系的X射线成像系统的图像质量改进。
- X射线成像 /
- 像元响应一致性 /
- 非均匀性校正 /
- 线性校正 /
- 图像处理
Abstract: The nonuniformity was a major concern when X-ray images were evaluated, and it would affect both the detection and classification ability of the imaging instrument. The theoretical principles of the cause for the nonuniformity of digital image were analyzed, linear photoelectric response model of each pixel channel in the imaging instrument was presented, and a multipoint linear fitting correction algorithm was proposed. The images and the standard deviations for the images were given before and after the correction. The nonuniformity correction method was useful for the improvment of image quality when linear relationship between image pixel output and X-ray tube current existed.
- X radiography /
- Pixel response uniformity /
- Nonuniformity correction /
- Linear correction /
- Image processing

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