有损压缩JPEG在相移法位相解调的应用评估

探讨了基于JPEG的有损压缩方法在相移法位相解调中的应用前景。简介了当今流行的JPEG有损压缩技术和相移技术。针对三维测量中的相移技术,使用专业软件对四步相移法中拍摄的图像进行各种压缩比的压缩,解压后再解调出相位,与未经压缩的原图解调出的相位进行比较。指出图像的压缩对于相位的解调是有影响的,尤其是对于图像的边缘部分,变化较大,噪声较强,压缩丢失信息,解压后解调出的相位误差较大,但随着压缩比的下降,压缩质量的提高,解调出的相位误差不断下降。

Evaluation of using lossy-JPEG image compression in phase demodulation with phase shifting method

Using lossy-JPEG image compression in phase demodulation with phase-shifting method is evaluated. The popular lossy-JPEG image compression arithmetic and phase-shifting technology are introduced. ACDSEE4.0 is used to compress the pictures used in four-step phase-measuring method with different ratios. The pictures are decompressed and the phase demodulated. It is compared with the phase demodulated with original pictures. That image compression could degenerate the phase demodulated is found out, especially in the edge of the picture. It is with the lower compress ratio, the quality of compression raise, and the errors of the phase decline.