基于DSP的LCoS嵌入式图像投影接口设计

Embedded LCoS Image Projection Display Interface Based on DSP

采用ADSP-BF561实现嵌入式系统LCoS投影显示系统接口,该设计方案不需要电平转换和串并转换,重点分析了使用该DSP对图像的输出控制,对图像数据进行了色彩空间转换和梯形校正。在色彩空间转换中,采用色彩空间转换公式将YUV空间图像数据转换为RGB空间图像数据;在梯形校正中,将所得到的RGB图像数据进行插值运算后再进行梯形转换,并将得到的梯形图形与原图形进行了对比。本设计实现简单,可以得到在时间资源和空间资源上均达到要求、分辨率为QVGA的投影图像,具有可编程图像处理、可扩展和低功耗的特点。

ADSP-BF561 was used to implement the embedded LCoS（Liquid Crystal on Silicon） image projection display interface. The framework of the interface was proposed,and level switch and serial-to-parallel were avoided. This paper emphasized on the controlling of the image outputs,and the processing of color conversions and trapezoid correction of image data by DSP. In color conversions,image data in YUV color space was conversed to image data in RGB color space by color conversion equations. In trapezoid correction,the obtained RGB data was calculated by trapezoid transforming after image interpolation,and made the contrast of the trapezoid image with the source image. The design was programmable,extensible,and low-powered. It was implemented in a simply way. A QVGA projecting image was obtained,and the time and space resources met the requirements.