In recent years infrared thermal imaging technology widely used in industrial, commercial and military, the typical applications include video conferencing, fire, security systems, automotive collision avoidance systems, and military missile systems. These applications have increasing demands for Infrared images, but because of the performance of infrared detectors and the working environment, the infrared image has low quality. In this paper, 14 bits data were collected by the infrared imaging system ThermaCAMP30 and image processing algorithms were studied in ASIC (Application Specific Integrated Circuit), where, the algorithms include one point correction, two correction, dead pixel replacement, histogram stretching, and image enhancement algorithms. The experiment results enhanced the visual effects of 8 bits image, enhanced the contrast of the background and objects, restrained noise and improved the detail of infrared thermal image.