Spectral enhancement includes linear contrast stretch, non-linear contrast stretch, histogram equalization and histogram matching etc.

光谱增强包括线性反差拉伸、非线性反差拉伸、直方图均衡化和直方图匹配等方法。

youdao

The targets SNR(Signal Noise Ratio)and contrast are very low when the target is in the sea background in which there are sea waves and the reflexing light from the stretch welter.

海面背景下海面及连绵起伏的波浪反光使图像的信噪比和对比度都较低，而且舰船目标像素较少。

youdao

The targets SNRand contrast are very low when the target is in the sea background in which there are sea waves and the reflexing light from the stretch welter.

海面背景下海面及连绵起伏的波浪反光使图像的信噪比和对比度都较低，而且舰船目标像素较少。

youdao

By contrast, the ASEAN parleys, which now stretch fully a week, have become notable for the sheer breadth of their agendas.

CNN: HEN THE FOREIGN MINISTERS