高动态范围场景再现技术广泛应用于消费电子、虚拟现实、摄影以及计算机视觉等领域。针对目前大多数高动态范围场景再现方法很难有效兼顾场景的整体效果和局部细节的问题, 本文提出了基于混合映射的高动态范围场景再现方法。首先将输入的高动态范围场景从RGB颜色空间转换到HSV颜色空间, 得到原始图像的3个分量: 色调、饱和度和亮度; 然后利用对数方程将亮度分量转换到对数域, 以便符合人类对场景亮度的感知机理, 并利用具有sigmoidal函数特性的反正切函数自适应地压缩全局动态范围, 以得到良好的整体效果; 接着采用改进的SSR方法对全局压缩后的亮度图像进行局部映射, 以增强图像亮区和暗区的细节信息; 最后, 对饱和度分量进行自适应调整, 并将图像由HSV颜色空间转换到RGB颜色空间得到最终的映射图像。选取10组不同的高动态范围场景, 从主观和客观两方面进行比较分析。实验结果表明: 本文提出的方法既保持了良好的整体效果, 又充分保留了图像的局部细节, 使图像看起来更加生动自然; 同时该方法计算速度快, 具有很高的效率。本文算法优于其他5种典型的比较算法, 在大多数高动态范围场景再现过程中取得了令人满意的效果。

High dynamic range (HDR) scene reproduction has been widely used in consumer electronics, virtual reality, photography, and computer vision. An HDR scene reproduction algorithm based on hybrid mapping was proposed to address the problem of poor overall appearance and local details of an existing work. First, HDR scenes were transformed from the RGB to HSV color space, which converts the color information to hue, saturation, and luminance value components. Second, the luminance values were transformed into a logarithm domain using a special logarithm function, and an adaptive arctangent function was used to compress the global dynamic range, which then enables achieving good overall appearance. Then, the improved single-scale Retinex algorithm was applied to local detail adjustment, which enhanced the details of the bright and dark areas. Finally, the saturation component was adjusted, and the color information was restored from HSV to RGB color space. Ten types of HDR scenes were tested in the experiments, and the obtained results were compared both subjectively and objectively. The experimental results demonstrate that the proposed method enables good visual appearance and preserves more details. Moreover, the proposed algorithm has a low computation cost. The proposed algorithm is better than five traditional methods and can produce desirable images in most HDR scenes.