这篇文章主要讲解了“C++中怎么使用cvtColor实现颜色转换”，文中的讲解内容简单清晰，易于学习与理解，下面请大家跟着小编的思路慢慢深入，一起来研究和学习“C++中怎么使用cvtColor实现颜色转换”吧！
前言
在我们读取图像时通常会用到imread（）函数，里面flags可以决定通道数，来得到我们想要的图像，比如：
-1 按解码得到的方式读入图像；
0 单通道 灰度图；
1 三通道 彩色；
当我们想要其他类型的图像时，这种方法就有一些局限性了，所以我们有必要了解cvtColor 这是一种颜色空间转换函数。
源码
void cvtColor(InputArray src, OutputArray dst, int code, int dstCn = 0);src 输入图像dst 输出图像code 代码颜色空间转换代码dstCn 目标图像中的信道数; 如果该参数为0，则通道的数量自动从SRC和code派生。可以支持RGB HSV 等颜色空间转换（建议不要使用人脸尝试，有些效果懂的都懂）
代码：
int main(){Mat img1, img2, img3, img4;img1 = imread("猫1.jpg");imshow("原图", img1);cvtColor(img1, img2, COLOR_RGB2GRAY);imshow("灰度图", img2);cvtColor(img1, img3, COLOR_RGB2HSV);imshow("HSV", img3);cvtColor(img1, img4, COLOR_RGB2BGR);imshow("BGR", img4);waitKey(0);}效果图
代码颜色空间转换代码
enum ColorConversionCodes { COLOR_BGR2BGRA = 0, //!< add alpha channel to RGB or BGR image COLOR_RGB2RGBA = COLOR_BGR2BGRA, COLOR_BGRA2BGR = 1, //!< remove alpha channel from RGB or BGR image COLOR_RGBA2RGB = COLOR_BGRA2BGR, COLOR_BGR2RGBA = 2, //!< convert between RGB and BGR color spaces (with or without alpha channel) COLOR_RGB2BGRA = COLOR_BGR2RGBA, COLOR_RGBA2BGR = 3, COLOR_BGRA2RGB = COLOR_RGBA2BGR, COLOR_BGR2RGB = 4, COLOR_RGB2BGR = COLOR_BGR2RGB, COLOR_BGRA2RGBA = 5, COLOR_RGBA2BGRA = COLOR_BGRA2RGBA, COLOR_BGR2GRAY = 6, //!< convert between RGB/BGR and grayscale, @ref color_convert_rgb_gray "color conversions" COLOR_RGB2GRAY = 7, COLOR_GRAY2BGR = 8, COLOR_GRAY2RGB = COLOR_GRAY2BGR, COLOR_GRAY2BGRA = 9, COLOR_GRAY2RGBA = COLOR_GRAY2BGRA, COLOR_BGRA2GRAY = 10, COLOR_RGBA2GRAY = 11, COLOR_BGR2BGR565 = 12, //!< convert between RGB/BGR and BGR565 (16-bit images) COLOR_RGB2BGR565 = 13, COLOR_BGR5652BGR = 14, COLOR_BGR5652RGB = 15, COLOR_BGRA2BGR565 = 16, COLOR_RGBA2BGR565 = 17, COLOR_BGR5652BGRA = 18, COLOR_BGR5652RGBA = 19, COLOR_GRAY2BGR565 = 20, //!< convert between grayscale to BGR565 (16-bit images) COLOR_BGR5652GRAY = 21, COLOR_BGR2BGR555 = 22, //!< convert between RGB/BGR and BGR555 (16-bit images) COLOR_RGB2BGR555 = 23, COLOR_BGR5552BGR = 24, COLOR_BGR5552RGB = 25, COLOR_BGRA2BGR555 = 26, COLOR_RGBA2BGR555 = 27, COLOR_BGR5552BGRA = 28, COLOR_BGR5552RGBA = 29, COLOR_GRAY2BGR555 = 30, //!< convert between grayscale and BGR555 (16-bit images) COLOR_BGR5552GRAY = 31, COLOR_BGR2XYZ = 32, //!< convert RGB/BGR to CIE XYZ, @ref color_convert_rgb_xyz "color conversions" COLOR_RGB2XYZ = 33, COLOR_XYZ2BGR = 34, COLOR_XYZ2RGB = 35, COLOR_BGR2YCrCb = 36, //!< convert RGB/BGR to luma-chroma (aka YCC), @ref color_convert_rgb_ycrcb "color conversions" COLOR_RGB2YCrCb = 37, COLOR_YCrCb2BGR = 38, COLOR_YCrCb2RGB = 39, COLOR_BGR2HSV = 40, //!< convert RGB/BGR to HSV (hue saturation value), @ref color_convert_rgb_hsv "color conversions" COLOR_RGB2HSV = 41, COLOR_BGR2Lab = 44, //!< convert RGB/BGR to CIE Lab, @ref color_convert_rgb_lab "color conversions" COLOR_RGB2Lab = 45, COLOR_BGR2Luv = 50, //!< convert RGB/BGR to CIE Luv, @ref color_convert_rgb_luv "color conversions" COLOR_RGB2Luv = 51, COLOR_BGR2HLS = 52, //!< convert RGB/BGR to HLS (hue lightness saturation), @ref color_convert_rgb_hls "color conversions" COLOR_RGB2HLS = 53, COLOR_HSV2BGR = 54, //!< backward conversions to RGB/BGR COLOR_HSV2RGB = 55, COLOR_Lab2BGR = 56, COLOR_Lab2RGB = 57, COLOR_Luv2BGR = 58, COLOR_Luv2RGB = 59, COLOR_HLS2BGR = 60, COLOR_HLS2RGB = 61, COLOR_BGR2HSV_FULL = 66, COLOR_RGB2HSV_FULL = 67, COLOR_BGR2HLS_FULL = 68, COLOR_RGB2HLS_FULL = 69, COLOR_HSV2BGR_FULL = 70, COLOR_HSV2RGB_FULL = 71, COLOR_HLS2BGR_FULL = 72, COLOR_HLS2RGB_FULL = 73, COLOR_LBGR2Lab = 74, COLOR_LRGB2Lab = 75, COLOR_LBGR2Luv = 76, COLOR_LRGB2Luv = 77, COLOR_Lab2LBGR = 78, COLOR_Lab2LRGB = 79, COLOR_Luv2LBGR = 80, COLOR_Luv2LRGB = 81, COLOR_BGR2YUV = 82, //!< convert between RGB/BGR and YUV COLOR_RGB2YUV = 83, COLOR_YUV2BGR = 84, COLOR_YUV2RGB = 85, //! YUV 4:2:0 family to RGB COLOR_YUV2RGB_NV12 = 90, COLOR_YUV2BGR_NV12 = 91, COLOR_YUV2RGB_NV21 = 92, COLOR_YUV2BGR_NV21 = 93, COLOR_YUV420sp2RGB = COLOR_YUV2RGB_NV21, COLOR_YUV420sp2BGR = COLOR_YUV2BGR_NV21, COLOR_YUV2RGBA_NV12 = 94, COLOR_YUV2BGRA_NV12 = 95, COLOR_YUV2RGBA_NV21 = 96, COLOR_YUV2BGRA_NV21 = 97, COLOR_YUV420sp2RGBA = COLOR_YUV2RGBA_NV21, COLOR_YUV420sp2BGRA = COLOR_YUV2BGRA_NV21, COLOR_YUV2RGB_YV12 = 98, COLOR_YUV2BGR_YV12 = 99, COLOR_YUV2RGB_IYUV = 100, COLOR_YUV2BGR_IYUV = 101, COLOR_YUV2RGB_I420 = COLOR_YUV2RGB_IYUV, COLOR_YUV2BGR_I420 = COLOR_YUV2BGR_IYUV, COLOR_YUV420p2RGB = COLOR_YUV2RGB_YV12, COLOR_YUV420p2BGR = COLOR_YUV2BGR_YV12, COLOR_YUV2RGBA_YV12 = 102, COLOR_YUV2BGRA_YV12 = 103, COLOR_YUV2RGBA_IYUV = 104, COLOR_YUV2BGRA_IYUV = 105, COLOR_YUV2RGBA_I420 = COLOR_YUV2RGBA_IYUV, COLOR_YUV2BGRA_I420 = COLOR_YUV2BGRA_IYUV, COLOR_YUV420p2RGBA = COLOR_YUV2RGBA_YV12, COLOR_YUV420p2BGRA = COLOR_YUV2BGRA_YV12, COLOR_YUV2GRAY_420 = 106, COLOR_YUV2GRAY_NV21 = COLOR_YUV2GRAY_420, COLOR_YUV2GRAY_NV12 = COLOR_YUV2GRAY_420, COLOR_YUV2GRAY_YV12 = COLOR_YUV2GRAY_420, COLOR_YUV2GRAY_IYUV = COLOR_YUV2GRAY_420, COLOR_YUV2GRAY_I420 = COLOR_YUV2GRAY_420, COLOR_YUV420sp2GRAY = COLOR_YUV2GRAY_420, COLOR_YUV420p2GRAY = COLOR_YUV2GRAY_420, //! YUV 4:2:2 family to RGB COLOR_YUV2RGB_UYVY = 107, COLOR_YUV2BGR_UYVY = 108, //COLOR_YUV2RGB_VYUY = 109, //COLOR_YUV2BGR_VYUY = 110, COLOR_YUV2RGB_Y422 = COLOR_YUV2RGB_UYVY, COLOR_YUV2BGR_Y422 = COLOR_YUV2BGR_UYVY, COLOR_YUV2RGB_UYNV = COLOR_YUV2RGB_UYVY, COLOR_YUV2BGR_UYNV = COLOR_YUV2BGR_UYVY, COLOR_YUV2RGBA_UYVY = 111, COLOR_YUV2BGRA_UYVY = 112, //COLOR_YUV2RGBA_VYUY = 113, //COLOR_YUV2BGRA_VYUY = 114, COLOR_YUV2RGBA_Y422 = COLOR_YUV2RGBA_UYVY, COLOR_YUV2BGRA_Y422 = COLOR_YUV2BGRA_UYVY, COLOR_YUV2RGBA_UYNV = COLOR_YUV2RGBA_UYVY, COLOR_YUV2BGRA_UYNV = COLOR_YUV2BGRA_UYVY, COLOR_YUV2RGB_YUY2 = 115, COLOR_YUV2BGR_YUY2 = 116, COLOR_YUV2RGB_YVYU = 117, COLOR_YUV2BGR_YVYU = 118, COLOR_YUV2RGB_YUYV = COLOR_YUV2RGB_YUY2, COLOR_YUV2BGR_YUYV = COLOR_YUV2BGR_YUY2, COLOR_YUV2RGB_YUNV = COLOR_YUV2RGB_YUY2, COLOR_YUV2BGR_YUNV = COLOR_YUV2BGR_YUY2, COLOR_YUV2RGBA_YUY2 = 119, COLOR_YUV2BGRA_YUY2 = 120, COLOR_YUV2RGBA_YVYU = 121, COLOR_YUV2BGRA_YVYU = 122, COLOR_YUV2RGBA_YUYV = COLOR_YUV2RGBA_YUY2, COLOR_YUV2BGRA_YUYV = COLOR_YUV2BGRA_YUY2, COLOR_YUV2RGBA_YUNV = COLOR_YUV2RGBA_YUY2, COLOR_YUV2BGRA_YUNV = COLOR_YUV2BGRA_YUY2, COLOR_YUV2GRAY_UYVY = 123, COLOR_YUV2GRAY_YUY2 = 124, //CV_YUV2GRAY_VYUY = CV_YUV2GRAY_UYVY, COLOR_YUV2GRAY_Y422 = COLOR_YUV2GRAY_UYVY, COLOR_YUV2GRAY_UYNV = COLOR_YUV2GRAY_UYVY, COLOR_YUV2GRAY_YVYU = COLOR_YUV2GRAY_YUY2, COLOR_YUV2GRAY_YUYV = COLOR_YUV2GRAY_YUY2, COLOR_YUV2GRAY_YUNV = COLOR_YUV2GRAY_YUY2, //! alpha premultiplication COLOR_RGBA2mRGBA = 125, COLOR_mRGBA2RGBA = 126, //! RGB to YUV 4:2:0 family COLOR_RGB2YUV_I420 = 127, COLOR_BGR2YUV_I420 = 128, COLOR_RGB2YUV_IYUV = COLOR_RGB2YUV_I420, COLOR_BGR2YUV_IYUV = COLOR_BGR2YUV_I420, COLOR_RGBA2YUV_I420 = 129, COLOR_BGRA2YUV_I420 = 130, COLOR_RGBA2YUV_IYUV = COLOR_RGBA2YUV_I420, COLOR_BGRA2YUV_IYUV = COLOR_BGRA2YUV_I420, COLOR_RGB2YUV_YV12 = 131, COLOR_BGR2YUV_YV12 = 132, COLOR_RGBA2YUV_YV12 = 133, COLOR_BGRA2YUV_YV12 = 134, //! Demosaicing COLOR_BayerBG2BGR = 46, COLOR_BayerGB2BGR = 47, COLOR_BayerRG2BGR = 48, COLOR_BayerGR2BGR = 49, COLOR_BayerBG2RGB = COLOR_BayerRG2BGR, COLOR_BayerGB2RGB = COLOR_BayerGR2BGR, COLOR_BayerRG2RGB = COLOR_BayerBG2BGR, COLOR_BayerGR2RGB = COLOR_BayerGB2BGR, COLOR_BayerBG2GRAY = 86, COLOR_BayerGB2GRAY = 87, COLOR_BayerRG2GRAY = 88, COLOR_BayerGR2GRAY = 89, //! Demosaicing using Variable Number of Gradients COLOR_BayerBG2BGR_VNG = 62, COLOR_BayerGB2BGR_VNG = 63, COLOR_BayerRG2BGR_VNG = 64, COLOR_BayerGR2BGR_VNG = 65, COLOR_BayerBG2RGB_VNG = COLOR_BayerRG2BGR_VNG, COLOR_BayerGB2RGB_VNG = COLOR_BayerGR2BGR_VNG, COLOR_BayerRG2RGB_VNG = COLOR_BayerBG2BGR_VNG, COLOR_BayerGR2RGB_VNG = COLOR_BayerGB2BGR_VNG, //! Edge-Aware Demosaicing COLOR_BayerBG2BGR_EA = 135, COLOR_BayerGB2BGR_EA = 136, COLOR_BayerRG2BGR_EA = 137, COLOR_BayerGR2BGR_EA = 138, COLOR_BayerBG2RGB_EA = COLOR_BayerRG2BGR_EA, COLOR_BayerGB2RGB_EA = COLOR_BayerGR2BGR_EA, COLOR_BayerRG2RGB_EA = COLOR_BayerBG2BGR_EA, COLOR_BayerGR2RGB_EA = COLOR_BayerGB2BGR_EA, //! Demosaicing with alpha channel COLOR_BayerBG2BGRA = 139, COLOR_BayerGB2BGRA = 140, COLOR_BayerRG2BGRA = 141, COLOR_BayerGR2BGRA = 142, COLOR_BayerBG2RGBA = COLOR_BayerRG2BGRA, COLOR_BayerGB2RGBA = COLOR_BayerGR2BGRA, COLOR_BayerRG2RGBA = COLOR_BayerBG2BGRA, COLOR_BayerGR2RGBA = COLOR_BayerGB2BGRA, COLOR_COLORCVT_MAX = 143};感谢各位的阅读，以上就是“C++中怎么使用cvtColor实现颜色转换”的内容了，经过本文的学习后，相信大家对C++中怎么使用cvtColor实现颜色转换这一问题有了更深刻的体会，具体使用情况还需要大家实践验证。这里是编程网，小编将为大家推送更多相关知识点的文章，欢迎关注！
