OpenCV  4.6.0
Open Source Computer Vision
Enumerations | Functions
Color Space Conversions

Enumerations

enum  cv::ColorConversionCodes {
  cv::COLOR_BGR2BGRA = 0,
  cv::COLOR_RGB2RGBA = COLOR_BGR2BGRA,
  cv::COLOR_BGRA2BGR = 1,
  cv::COLOR_RGBA2RGB = COLOR_BGRA2BGR,
  cv::COLOR_BGR2RGBA = 2,
  cv::COLOR_RGB2BGRA = COLOR_BGR2RGBA,
  cv::COLOR_RGBA2BGR = 3,
  cv::COLOR_BGRA2RGB = COLOR_RGBA2BGR,
  cv::COLOR_BGR2RGB = 4,
  cv::COLOR_RGB2BGR = COLOR_BGR2RGB,
  cv::COLOR_BGRA2RGBA = 5,
  cv::COLOR_RGBA2BGRA = COLOR_BGRA2RGBA,
  cv::COLOR_BGR2GRAY = 6,
  cv::COLOR_RGB2GRAY = 7,
  cv::COLOR_GRAY2BGR = 8,
  cv::COLOR_GRAY2RGB = COLOR_GRAY2BGR,
  cv::COLOR_GRAY2BGRA = 9,
  cv::COLOR_GRAY2RGBA = COLOR_GRAY2BGRA,
  cv::COLOR_BGRA2GRAY = 10,
  cv::COLOR_RGBA2GRAY = 11,
  cv::COLOR_BGR2BGR565 = 12,
  cv::COLOR_RGB2BGR565 = 13,
  cv::COLOR_BGR5652BGR = 14,
  cv::COLOR_BGR5652RGB = 15,
  cv::COLOR_BGRA2BGR565 = 16,
  cv::COLOR_RGBA2BGR565 = 17,
  cv::COLOR_BGR5652BGRA = 18,
  cv::COLOR_BGR5652RGBA = 19,
  cv::COLOR_GRAY2BGR565 = 20,
  cv::COLOR_BGR5652GRAY = 21,
  cv::COLOR_BGR2BGR555 = 22,
  cv::COLOR_RGB2BGR555 = 23,
  cv::COLOR_BGR5552BGR = 24,
  cv::COLOR_BGR5552RGB = 25,
  cv::COLOR_BGRA2BGR555 = 26,
  cv::COLOR_RGBA2BGR555 = 27,
  cv::COLOR_BGR5552BGRA = 28,
  cv::COLOR_BGR5552RGBA = 29,
  cv::COLOR_GRAY2BGR555 = 30,
  cv::COLOR_BGR5552GRAY = 31,
  cv::COLOR_BGR2XYZ = 32,
  cv::COLOR_RGB2XYZ = 33,
  cv::COLOR_XYZ2BGR = 34,
  cv::COLOR_XYZ2RGB = 35,
  cv::COLOR_BGR2YCrCb = 36,
  cv::COLOR_RGB2YCrCb = 37,
  cv::COLOR_YCrCb2BGR = 38,
  cv::COLOR_YCrCb2RGB = 39,
  cv::COLOR_BGR2HSV = 40,
  cv::COLOR_RGB2HSV = 41,
  cv::COLOR_BGR2Lab = 44,
  cv::COLOR_RGB2Lab = 45,
  cv::COLOR_BGR2Luv = 50,
  cv::COLOR_RGB2Luv = 51,
  cv::COLOR_BGR2HLS = 52,
  cv::COLOR_RGB2HLS = 53,
  cv::COLOR_HSV2BGR = 54,
  cv::COLOR_HSV2RGB = 55,
  cv::COLOR_Lab2BGR = 56,
  cv::COLOR_Lab2RGB = 57,
  cv::COLOR_Luv2BGR = 58,
  cv::COLOR_Luv2RGB = 59,
  cv::COLOR_HLS2BGR = 60,
  cv::COLOR_HLS2RGB = 61,
  cv::COLOR_BGR2HSV_FULL = 66,
  cv::COLOR_RGB2HSV_FULL = 67,
  cv::COLOR_BGR2HLS_FULL = 68,
  cv::COLOR_RGB2HLS_FULL = 69,
  cv::COLOR_HSV2BGR_FULL = 70,
  cv::COLOR_HSV2RGB_FULL = 71,
  cv::COLOR_HLS2BGR_FULL = 72,
  cv::COLOR_HLS2RGB_FULL = 73,
  cv::COLOR_LBGR2Lab = 74,
  cv::COLOR_LRGB2Lab = 75,
  cv::COLOR_LBGR2Luv = 76,
  cv::COLOR_LRGB2Luv = 77,
  cv::COLOR_Lab2LBGR = 78,
  cv::COLOR_Lab2LRGB = 79,
  cv::COLOR_Luv2LBGR = 80,
  cv::COLOR_Luv2LRGB = 81,
  cv::COLOR_BGR2YUV = 82,
  cv::COLOR_RGB2YUV = 83,
  cv::COLOR_YUV2BGR = 84,
  cv::COLOR_YUV2RGB = 85,
  cv::COLOR_YUV2RGB_NV12 = 90,
  cv::COLOR_YUV2BGR_NV12 = 91,
  cv::COLOR_YUV2RGB_NV21 = 92,
  cv::COLOR_YUV2BGR_NV21 = 93,
  cv::COLOR_YUV420sp2RGB = COLOR_YUV2RGB_NV21,
  cv::COLOR_YUV420sp2BGR = COLOR_YUV2BGR_NV21,
  cv::COLOR_YUV2RGBA_NV12 = 94,
  cv::COLOR_YUV2BGRA_NV12 = 95,
  cv::COLOR_YUV2RGBA_NV21 = 96,
  cv::COLOR_YUV2BGRA_NV21 = 97,
  cv::COLOR_YUV420sp2RGBA = COLOR_YUV2RGBA_NV21,
  cv::COLOR_YUV420sp2BGRA = COLOR_YUV2BGRA_NV21,
  cv::COLOR_YUV2RGB_YV12 = 98,
  cv::COLOR_YUV2BGR_YV12 = 99,
  cv::COLOR_YUV2RGB_IYUV = 100,
  cv::COLOR_YUV2BGR_IYUV = 101,
  cv::COLOR_YUV2RGB_I420 = COLOR_YUV2RGB_IYUV,
  cv::COLOR_YUV2BGR_I420 = COLOR_YUV2BGR_IYUV,
  cv::COLOR_YUV420p2RGB = COLOR_YUV2RGB_YV12,
  cv::COLOR_YUV420p2BGR = COLOR_YUV2BGR_YV12,
  cv::COLOR_YUV2RGBA_YV12 = 102,
  cv::COLOR_YUV2BGRA_YV12 = 103,
  cv::COLOR_YUV2RGBA_IYUV = 104,
  cv::COLOR_YUV2BGRA_IYUV = 105,
  cv::COLOR_YUV2RGBA_I420 = COLOR_YUV2RGBA_IYUV,
  cv::COLOR_YUV2BGRA_I420 = COLOR_YUV2BGRA_IYUV,
  cv::COLOR_YUV420p2RGBA = COLOR_YUV2RGBA_YV12,
  cv::COLOR_YUV420p2BGRA = COLOR_YUV2BGRA_YV12,
  cv::COLOR_YUV2GRAY_420 = 106,
  cv::COLOR_YUV2GRAY_NV21 = COLOR_YUV2GRAY_420,
  cv::COLOR_YUV2GRAY_NV12 = COLOR_YUV2GRAY_420,
  cv::COLOR_YUV2GRAY_YV12 = COLOR_YUV2GRAY_420,
  cv::COLOR_YUV2GRAY_IYUV = COLOR_YUV2GRAY_420,
  cv::COLOR_YUV2GRAY_I420 = COLOR_YUV2GRAY_420,
  cv::COLOR_YUV420sp2GRAY = COLOR_YUV2GRAY_420,
  cv::COLOR_YUV420p2GRAY = COLOR_YUV2GRAY_420,
  cv::COLOR_YUV2RGB_UYVY = 107,
  cv::COLOR_YUV2BGR_UYVY = 108,
  cv::COLOR_YUV2RGB_Y422 = COLOR_YUV2RGB_UYVY,
  cv::COLOR_YUV2BGR_Y422 = COLOR_YUV2BGR_UYVY,
  cv::COLOR_YUV2RGB_UYNV = COLOR_YUV2RGB_UYVY,
  cv::COLOR_YUV2BGR_UYNV = COLOR_YUV2BGR_UYVY,
  cv::COLOR_YUV2RGBA_UYVY = 111,
  cv::COLOR_YUV2BGRA_UYVY = 112,
  cv::COLOR_YUV2RGBA_Y422 = COLOR_YUV2RGBA_UYVY,
  cv::COLOR_YUV2BGRA_Y422 = COLOR_YUV2BGRA_UYVY,
  cv::COLOR_YUV2RGBA_UYNV = COLOR_YUV2RGBA_UYVY,
  cv::COLOR_YUV2BGRA_UYNV = COLOR_YUV2BGRA_UYVY,
  cv::COLOR_YUV2RGB_YUY2 = 115,
  cv::COLOR_YUV2BGR_YUY2 = 116,
  cv::COLOR_YUV2RGB_YVYU = 117,
  cv::COLOR_YUV2BGR_YVYU = 118,
  cv::COLOR_YUV2RGB_YUYV = COLOR_YUV2RGB_YUY2,
  cv::COLOR_YUV2BGR_YUYV = COLOR_YUV2BGR_YUY2,
  cv::COLOR_YUV2RGB_YUNV = COLOR_YUV2RGB_YUY2,
  cv::COLOR_YUV2BGR_YUNV = COLOR_YUV2BGR_YUY2,
  cv::COLOR_YUV2RGBA_YUY2 = 119,
  cv::COLOR_YUV2BGRA_YUY2 = 120,
  cv::COLOR_YUV2RGBA_YVYU = 121,
  cv::COLOR_YUV2BGRA_YVYU = 122,
  cv::COLOR_YUV2RGBA_YUYV = COLOR_YUV2RGBA_YUY2,
  cv::COLOR_YUV2BGRA_YUYV = COLOR_YUV2BGRA_YUY2,
  cv::COLOR_YUV2RGBA_YUNV = COLOR_YUV2RGBA_YUY2,
  cv::COLOR_YUV2BGRA_YUNV = COLOR_YUV2BGRA_YUY2,
  cv::COLOR_YUV2GRAY_UYVY = 123,
  cv::COLOR_YUV2GRAY_YUY2 = 124,
  cv::COLOR_YUV2GRAY_Y422 = COLOR_YUV2GRAY_UYVY,
  cv::COLOR_YUV2GRAY_UYNV = COLOR_YUV2GRAY_UYVY,
  cv::COLOR_YUV2GRAY_YVYU = COLOR_YUV2GRAY_YUY2,
  cv::COLOR_YUV2GRAY_YUYV = COLOR_YUV2GRAY_YUY2,
  cv::COLOR_YUV2GRAY_YUNV = COLOR_YUV2GRAY_YUY2,
  cv::COLOR_RGBA2mRGBA = 125,
  cv::COLOR_mRGBA2RGBA = 126,
  cv::COLOR_RGB2YUV_I420 = 127,
  cv::COLOR_BGR2YUV_I420 = 128,
  cv::COLOR_RGB2YUV_IYUV = COLOR_RGB2YUV_I420,
  cv::COLOR_BGR2YUV_IYUV = COLOR_BGR2YUV_I420,
  cv::COLOR_RGBA2YUV_I420 = 129,
  cv::COLOR_BGRA2YUV_I420 = 130,
  cv::COLOR_RGBA2YUV_IYUV = COLOR_RGBA2YUV_I420,
  cv::COLOR_BGRA2YUV_IYUV = COLOR_BGRA2YUV_I420,
  cv::COLOR_RGB2YUV_YV12 = 131,
  cv::COLOR_BGR2YUV_YV12 = 132,
  cv::COLOR_RGBA2YUV_YV12 = 133,
  cv::COLOR_BGRA2YUV_YV12 = 134,
  cv::COLOR_BayerBG2BGR = 46,
  cv::COLOR_BayerGB2BGR = 47,
  cv::COLOR_BayerRG2BGR = 48,
  cv::COLOR_BayerGR2BGR = 49,
  cv::COLOR_BayerRGGB2BGR = COLOR_BayerBG2BGR,
  cv::COLOR_BayerGRBG2BGR = COLOR_BayerGB2BGR,
  cv::COLOR_BayerBGGR2BGR = COLOR_BayerRG2BGR,
  cv::COLOR_BayerGBRG2BGR = COLOR_BayerGR2BGR,
  cv::COLOR_BayerRGGB2RGB = COLOR_BayerBGGR2BGR,
  cv::COLOR_BayerGRBG2RGB = COLOR_BayerGBRG2BGR,
  cv::COLOR_BayerBGGR2RGB = COLOR_BayerRGGB2BGR,
  cv::COLOR_BayerGBRG2RGB = COLOR_BayerGRBG2BGR,
  cv::COLOR_BayerBG2RGB = COLOR_BayerRG2BGR,
  cv::COLOR_BayerGB2RGB = COLOR_BayerGR2BGR,
  cv::COLOR_BayerRG2RGB = COLOR_BayerBG2BGR,
  cv::COLOR_BayerGR2RGB = COLOR_BayerGB2BGR,
  cv::COLOR_BayerBG2GRAY = 86,
  cv::COLOR_BayerGB2GRAY = 87,
  cv::COLOR_BayerRG2GRAY = 88,
  cv::COLOR_BayerGR2GRAY = 89,
  cv::COLOR_BayerRGGB2GRAY = COLOR_BayerBG2GRAY,
  cv::COLOR_BayerGRBG2GRAY = COLOR_BayerGB2GRAY,
  cv::COLOR_BayerBGGR2GRAY = COLOR_BayerRG2GRAY,
  cv::COLOR_BayerGBRG2GRAY = COLOR_BayerGR2GRAY,
  cv::COLOR_BayerBG2BGR_VNG = 62,
  cv::COLOR_BayerGB2BGR_VNG = 63,
  cv::COLOR_BayerRG2BGR_VNG = 64,
  cv::COLOR_BayerGR2BGR_VNG = 65,
  cv::COLOR_BayerRGGB2BGR_VNG = COLOR_BayerBG2BGR_VNG,
  cv::COLOR_BayerGRBG2BGR_VNG = COLOR_BayerGB2BGR_VNG,
  cv::COLOR_BayerBGGR2BGR_VNG = COLOR_BayerRG2BGR_VNG,
  cv::COLOR_BayerGBRG2BGR_VNG = COLOR_BayerGR2BGR_VNG,
  cv::COLOR_BayerRGGB2RGB_VNG = COLOR_BayerBGGR2BGR_VNG,
  cv::COLOR_BayerGRBG2RGB_VNG = COLOR_BayerGBRG2BGR_VNG,
  cv::COLOR_BayerBGGR2RGB_VNG = COLOR_BayerRGGB2BGR_VNG,
  cv::COLOR_BayerGBRG2RGB_VNG = COLOR_BayerGRBG2BGR_VNG,
  cv::COLOR_BayerBG2RGB_VNG = COLOR_BayerRG2BGR_VNG,
  cv::COLOR_BayerGB2RGB_VNG = COLOR_BayerGR2BGR_VNG,
  cv::COLOR_BayerRG2RGB_VNG = COLOR_BayerBG2BGR_VNG,
  cv::COLOR_BayerGR2RGB_VNG = COLOR_BayerGB2BGR_VNG,
  cv::COLOR_BayerBG2BGR_EA = 135,
  cv::COLOR_BayerGB2BGR_EA = 136,
  cv::COLOR_BayerRG2BGR_EA = 137,
  cv::COLOR_BayerGR2BGR_EA = 138,
  cv::COLOR_BayerRGGB2BGR_EA = COLOR_BayerBG2BGR_EA,
  cv::COLOR_BayerGRBG2BGR_EA = COLOR_BayerGB2BGR_EA,
  cv::COLOR_BayerBGGR2BGR_EA = COLOR_BayerRG2BGR_EA,
  cv::COLOR_BayerGBRG2BGR_EA = COLOR_BayerGR2BGR_EA,
  cv::COLOR_BayerRGGB2RGB_EA = COLOR_BayerBGGR2BGR_EA,
  cv::COLOR_BayerGRBG2RGB_EA = COLOR_BayerGBRG2BGR_EA,
  cv::COLOR_BayerBGGR2RGB_EA = COLOR_BayerRGGB2BGR_EA,
  cv::COLOR_BayerGBRG2RGB_EA = COLOR_BayerGRBG2BGR_EA,
  cv::COLOR_BayerBG2RGB_EA = COLOR_BayerRG2BGR_EA,
  cv::COLOR_BayerGB2RGB_EA = COLOR_BayerGR2BGR_EA,
  cv::COLOR_BayerRG2RGB_EA = COLOR_BayerBG2BGR_EA,
  cv::COLOR_BayerGR2RGB_EA = COLOR_BayerGB2BGR_EA,
  cv::COLOR_BayerBG2BGRA = 139,
  cv::COLOR_BayerGB2BGRA = 140,
  cv::COLOR_BayerRG2BGRA = 141,
  cv::COLOR_BayerGR2BGRA = 142,
  cv::COLOR_BayerRGGB2BGRA = COLOR_BayerBG2BGRA,
  cv::COLOR_BayerGRBG2BGRA = COLOR_BayerGB2BGRA,
  cv::COLOR_BayerBGGR2BGRA = COLOR_BayerRG2BGRA,
  cv::COLOR_BayerGBRG2BGRA = COLOR_BayerGR2BGRA,
  cv::COLOR_BayerRGGB2RGBA = COLOR_BayerBGGR2BGRA,
  cv::COLOR_BayerGRBG2RGBA = COLOR_BayerGBRG2BGRA,
  cv::COLOR_BayerBGGR2RGBA = COLOR_BayerRGGB2BGRA,
  cv::COLOR_BayerGBRG2RGBA = COLOR_BayerGRBG2BGRA,
  cv::COLOR_BayerBG2RGBA = COLOR_BayerRG2BGRA,
  cv::COLOR_BayerGB2RGBA = COLOR_BayerGR2BGRA,
  cv::COLOR_BayerRG2RGBA = COLOR_BayerBG2BGRA,
  cv::COLOR_BayerGR2RGBA = COLOR_BayerGB2BGRA,
  cv::COLOR_COLORCVT_MAX = 143
}
 

Functions

void cv::cvtColor (InputArray src, OutputArray dst, int code, int dstCn=0)
 Converts an image from one color space to another. More...
 
void cv::cvtColorTwoPlane (InputArray src1, InputArray src2, OutputArray dst, int code)
 Converts an image from one color space to another where the source image is stored in two planes. More...
 
void cv::demosaicing (InputArray src, OutputArray dst, int code, int dstCn=0)
 main function for all demosaicing processes More...
 

Detailed Description

Enumeration Type Documentation

◆ ColorConversionCodes

#include <opencv2/imgproc.hpp>

the color conversion codes

See also
Color conversions
Enumerator
COLOR_BGR2BGRA 
Python: cv.COLOR_BGR2BGRA

add alpha channel to RGB or BGR image

COLOR_RGB2RGBA 
Python: cv.COLOR_RGB2RGBA
COLOR_BGRA2BGR 
Python: cv.COLOR_BGRA2BGR

remove alpha channel from RGB or BGR image

COLOR_RGBA2RGB 
Python: cv.COLOR_RGBA2RGB
COLOR_BGR2RGBA 
Python: cv.COLOR_BGR2RGBA

convert between RGB and BGR color spaces (with or without alpha channel)

COLOR_RGB2BGRA 
Python: cv.COLOR_RGB2BGRA
COLOR_RGBA2BGR 
Python: cv.COLOR_RGBA2BGR
COLOR_BGRA2RGB 
Python: cv.COLOR_BGRA2RGB
COLOR_BGR2RGB 
Python: cv.COLOR_BGR2RGB
COLOR_RGB2BGR 
Python: cv.COLOR_RGB2BGR
COLOR_BGRA2RGBA 
Python: cv.COLOR_BGRA2RGBA
COLOR_RGBA2BGRA 
Python: cv.COLOR_RGBA2BGRA
COLOR_BGR2GRAY 
Python: cv.COLOR_BGR2GRAY

convert between RGB/BGR and grayscale, color conversions

COLOR_RGB2GRAY 
Python: cv.COLOR_RGB2GRAY
COLOR_GRAY2BGR 
Python: cv.COLOR_GRAY2BGR
COLOR_GRAY2RGB 
Python: cv.COLOR_GRAY2RGB
COLOR_GRAY2BGRA 
Python: cv.COLOR_GRAY2BGRA
COLOR_GRAY2RGBA 
Python: cv.COLOR_GRAY2RGBA
COLOR_BGRA2GRAY 
Python: cv.COLOR_BGRA2GRAY
COLOR_RGBA2GRAY 
Python: cv.COLOR_RGBA2GRAY
COLOR_BGR2BGR565 
Python: cv.COLOR_BGR2BGR565

convert between RGB/BGR and BGR565 (16-bit images)

COLOR_RGB2BGR565 
Python: cv.COLOR_RGB2BGR565
COLOR_BGR5652BGR 
Python: cv.COLOR_BGR5652BGR
COLOR_BGR5652RGB 
Python: cv.COLOR_BGR5652RGB
COLOR_BGRA2BGR565 
Python: cv.COLOR_BGRA2BGR565
COLOR_RGBA2BGR565 
Python: cv.COLOR_RGBA2BGR565
COLOR_BGR5652BGRA 
Python: cv.COLOR_BGR5652BGRA
COLOR_BGR5652RGBA 
Python: cv.COLOR_BGR5652RGBA
COLOR_GRAY2BGR565 
Python: cv.COLOR_GRAY2BGR565

convert between grayscale to BGR565 (16-bit images)

COLOR_BGR5652GRAY 
Python: cv.COLOR_BGR5652GRAY
COLOR_BGR2BGR555 
Python: cv.COLOR_BGR2BGR555

convert between RGB/BGR and BGR555 (16-bit images)

COLOR_RGB2BGR555 
Python: cv.COLOR_RGB2BGR555
COLOR_BGR5552BGR 
Python: cv.COLOR_BGR5552BGR
COLOR_BGR5552RGB 
Python: cv.COLOR_BGR5552RGB
COLOR_BGRA2BGR555 
Python: cv.COLOR_BGRA2BGR555
COLOR_RGBA2BGR555 
Python: cv.COLOR_RGBA2BGR555
COLOR_BGR5552BGRA 
Python: cv.COLOR_BGR5552BGRA
COLOR_BGR5552RGBA 
Python: cv.COLOR_BGR5552RGBA
COLOR_GRAY2BGR555 
Python: cv.COLOR_GRAY2BGR555

convert between grayscale and BGR555 (16-bit images)

COLOR_BGR5552GRAY 
Python: cv.COLOR_BGR5552GRAY
COLOR_BGR2XYZ 
Python: cv.COLOR_BGR2XYZ

convert RGB/BGR to CIE XYZ, color conversions

COLOR_RGB2XYZ 
Python: cv.COLOR_RGB2XYZ
COLOR_XYZ2BGR 
Python: cv.COLOR_XYZ2BGR
COLOR_XYZ2RGB 
Python: cv.COLOR_XYZ2RGB
COLOR_BGR2YCrCb 
Python: cv.COLOR_BGR2YCrCb

convert RGB/BGR to luma-chroma (aka YCC), color conversions

COLOR_RGB2YCrCb 
Python: cv.COLOR_RGB2YCrCb
COLOR_YCrCb2BGR 
Python: cv.COLOR_YCrCb2BGR
COLOR_YCrCb2RGB 
Python: cv.COLOR_YCrCb2RGB
COLOR_BGR2HSV 
Python: cv.COLOR_BGR2HSV

convert RGB/BGR to HSV (hue saturation value) with H range 0..180 if 8 bit image, color conversions

COLOR_RGB2HSV 
Python: cv.COLOR_RGB2HSV
COLOR_BGR2Lab 
Python: cv.COLOR_BGR2Lab

convert RGB/BGR to CIE Lab, color conversions

COLOR_RGB2Lab 
Python: cv.COLOR_RGB2Lab
COLOR_BGR2Luv 
Python: cv.COLOR_BGR2Luv

convert RGB/BGR to CIE Luv, color conversions

COLOR_RGB2Luv 
Python: cv.COLOR_RGB2Luv
COLOR_BGR2HLS 
Python: cv.COLOR_BGR2HLS

convert RGB/BGR to HLS (hue lightness saturation) with H range 0..180 if 8 bit image, color conversions

COLOR_RGB2HLS 
Python: cv.COLOR_RGB2HLS
COLOR_HSV2BGR 
Python: cv.COLOR_HSV2BGR

backward conversions HSV to RGB/BGR with H range 0..180 if 8 bit image

COLOR_HSV2RGB 
Python: cv.COLOR_HSV2RGB
COLOR_Lab2BGR 
Python: cv.COLOR_Lab2BGR
COLOR_Lab2RGB 
Python: cv.COLOR_Lab2RGB
COLOR_Luv2BGR 
Python: cv.COLOR_Luv2BGR
COLOR_Luv2RGB 
Python: cv.COLOR_Luv2RGB
COLOR_HLS2BGR 
Python: cv.COLOR_HLS2BGR

backward conversions HLS to RGB/BGR with H range 0..180 if 8 bit image

COLOR_HLS2RGB 
Python: cv.COLOR_HLS2RGB
COLOR_BGR2HSV_FULL 
Python: cv.COLOR_BGR2HSV_FULL

convert RGB/BGR to HSV (hue saturation value) with H range 0..255 if 8 bit image, color conversions

COLOR_RGB2HSV_FULL 
Python: cv.COLOR_RGB2HSV_FULL
COLOR_BGR2HLS_FULL 
Python: cv.COLOR_BGR2HLS_FULL

convert RGB/BGR to HLS (hue lightness saturation) with H range 0..255 if 8 bit image, color conversions

COLOR_RGB2HLS_FULL 
Python: cv.COLOR_RGB2HLS_FULL
COLOR_HSV2BGR_FULL 
Python: cv.COLOR_HSV2BGR_FULL

backward conversions HSV to RGB/BGR with H range 0..255 if 8 bit image

COLOR_HSV2RGB_FULL 
Python: cv.COLOR_HSV2RGB_FULL
COLOR_HLS2BGR_FULL 
Python: cv.COLOR_HLS2BGR_FULL

backward conversions HLS to RGB/BGR with H range 0..255 if 8 bit image

COLOR_HLS2RGB_FULL 
Python: cv.COLOR_HLS2RGB_FULL
COLOR_LBGR2Lab 
Python: cv.COLOR_LBGR2Lab
COLOR_LRGB2Lab 
Python: cv.COLOR_LRGB2Lab
COLOR_LBGR2Luv 
Python: cv.COLOR_LBGR2Luv
COLOR_LRGB2Luv 
Python: cv.COLOR_LRGB2Luv
COLOR_Lab2LBGR 
Python: cv.COLOR_Lab2LBGR
COLOR_Lab2LRGB 
Python: cv.COLOR_Lab2LRGB
COLOR_Luv2LBGR 
Python: cv.COLOR_Luv2LBGR
COLOR_Luv2LRGB 
Python: cv.COLOR_Luv2LRGB
COLOR_BGR2YUV 
Python: cv.COLOR_BGR2YUV

convert between RGB/BGR and YUV

COLOR_RGB2YUV 
Python: cv.COLOR_RGB2YUV
COLOR_YUV2BGR 
Python: cv.COLOR_YUV2BGR
COLOR_YUV2RGB 
Python: cv.COLOR_YUV2RGB
COLOR_YUV2RGB_NV12 
Python: cv.COLOR_YUV2RGB_NV12

YUV 4:2:0 family to RGB.

COLOR_YUV2BGR_NV12 
Python: cv.COLOR_YUV2BGR_NV12
COLOR_YUV2RGB_NV21 
Python: cv.COLOR_YUV2RGB_NV21
COLOR_YUV2BGR_NV21 
Python: cv.COLOR_YUV2BGR_NV21
COLOR_YUV420sp2RGB 
Python: cv.COLOR_YUV420sp2RGB
COLOR_YUV420sp2BGR 
Python: cv.COLOR_YUV420sp2BGR
COLOR_YUV2RGBA_NV12 
Python: cv.COLOR_YUV2RGBA_NV12
COLOR_YUV2BGRA_NV12 
Python: cv.COLOR_YUV2BGRA_NV12
COLOR_YUV2RGBA_NV21 
Python: cv.COLOR_YUV2RGBA_NV21
COLOR_YUV2BGRA_NV21 
Python: cv.COLOR_YUV2BGRA_NV21
COLOR_YUV420sp2RGBA 
Python: cv.COLOR_YUV420sp2RGBA
COLOR_YUV420sp2BGRA 
Python: cv.COLOR_YUV420sp2BGRA
COLOR_YUV2RGB_YV12 
Python: cv.COLOR_YUV2RGB_YV12
COLOR_YUV2BGR_YV12 
Python: cv.COLOR_YUV2BGR_YV12
COLOR_YUV2RGB_IYUV 
Python: cv.COLOR_YUV2RGB_IYUV
COLOR_YUV2BGR_IYUV 
Python: cv.COLOR_YUV2BGR_IYUV
COLOR_YUV2RGB_I420 
Python: cv.COLOR_YUV2RGB_I420
COLOR_YUV2BGR_I420 
Python: cv.COLOR_YUV2BGR_I420
COLOR_YUV420p2RGB 
Python: cv.COLOR_YUV420p2RGB
COLOR_YUV420p2BGR 
Python: cv.COLOR_YUV420p2BGR
COLOR_YUV2RGBA_YV12 
Python: cv.COLOR_YUV2RGBA_YV12
COLOR_YUV2BGRA_YV12 
Python: cv.COLOR_YUV2BGRA_YV12
COLOR_YUV2RGBA_IYUV 
Python: cv.COLOR_YUV2RGBA_IYUV
COLOR_YUV2BGRA_IYUV 
Python: cv.COLOR_YUV2BGRA_IYUV
COLOR_YUV2RGBA_I420 
Python: cv.COLOR_YUV2RGBA_I420
COLOR_YUV2BGRA_I420 
Python: cv.COLOR_YUV2BGRA_I420
COLOR_YUV420p2RGBA 
Python: cv.COLOR_YUV420p2RGBA
COLOR_YUV420p2BGRA 
Python: cv.COLOR_YUV420p2BGRA
COLOR_YUV2GRAY_420 
Python: cv.COLOR_YUV2GRAY_420
COLOR_YUV2GRAY_NV21 
Python: cv.COLOR_YUV2GRAY_NV21
COLOR_YUV2GRAY_NV12 
Python: cv.COLOR_YUV2GRAY_NV12
COLOR_YUV2GRAY_YV12 
Python: cv.COLOR_YUV2GRAY_YV12
COLOR_YUV2GRAY_IYUV 
Python: cv.COLOR_YUV2GRAY_IYUV
COLOR_YUV2GRAY_I420 
Python: cv.COLOR_YUV2GRAY_I420
COLOR_YUV420sp2GRAY 
Python: cv.COLOR_YUV420sp2GRAY
COLOR_YUV420p2GRAY 
Python: cv.COLOR_YUV420p2GRAY
COLOR_YUV2RGB_UYVY 
Python: cv.COLOR_YUV2RGB_UYVY

YUV 4:2:2 family to RGB.

COLOR_YUV2BGR_UYVY 
Python: cv.COLOR_YUV2BGR_UYVY
COLOR_YUV2RGB_Y422 
Python: cv.COLOR_YUV2RGB_Y422
COLOR_YUV2BGR_Y422 
Python: cv.COLOR_YUV2BGR_Y422
COLOR_YUV2RGB_UYNV 
Python: cv.COLOR_YUV2RGB_UYNV
COLOR_YUV2BGR_UYNV 
Python: cv.COLOR_YUV2BGR_UYNV
COLOR_YUV2RGBA_UYVY 
Python: cv.COLOR_YUV2RGBA_UYVY
COLOR_YUV2BGRA_UYVY 
Python: cv.COLOR_YUV2BGRA_UYVY
COLOR_YUV2RGBA_Y422 
Python: cv.COLOR_YUV2RGBA_Y422
COLOR_YUV2BGRA_Y422 
Python: cv.COLOR_YUV2BGRA_Y422
COLOR_YUV2RGBA_UYNV 
Python: cv.COLOR_YUV2RGBA_UYNV
COLOR_YUV2BGRA_UYNV 
Python: cv.COLOR_YUV2BGRA_UYNV
COLOR_YUV2RGB_YUY2 
Python: cv.COLOR_YUV2RGB_YUY2
COLOR_YUV2BGR_YUY2 
Python: cv.COLOR_YUV2BGR_YUY2
COLOR_YUV2RGB_YVYU 
Python: cv.COLOR_YUV2RGB_YVYU
COLOR_YUV2BGR_YVYU 
Python: cv.COLOR_YUV2BGR_YVYU
COLOR_YUV2RGB_YUYV 
Python: cv.COLOR_YUV2RGB_YUYV
COLOR_YUV2BGR_YUYV 
Python: cv.COLOR_YUV2BGR_YUYV
COLOR_YUV2RGB_YUNV 
Python: cv.COLOR_YUV2RGB_YUNV
COLOR_YUV2BGR_YUNV 
Python: cv.COLOR_YUV2BGR_YUNV
COLOR_YUV2RGBA_YUY2 
Python: cv.COLOR_YUV2RGBA_YUY2
COLOR_YUV2BGRA_YUY2 
Python: cv.COLOR_YUV2BGRA_YUY2
COLOR_YUV2RGBA_YVYU 
Python: cv.COLOR_YUV2RGBA_YVYU
COLOR_YUV2BGRA_YVYU 
Python: cv.COLOR_YUV2BGRA_YVYU
COLOR_YUV2RGBA_YUYV 
Python: cv.COLOR_YUV2RGBA_YUYV
COLOR_YUV2BGRA_YUYV 
Python: cv.COLOR_YUV2BGRA_YUYV
COLOR_YUV2RGBA_YUNV 
Python: cv.COLOR_YUV2RGBA_YUNV
COLOR_YUV2BGRA_YUNV 
Python: cv.COLOR_YUV2BGRA_YUNV
COLOR_YUV2GRAY_UYVY 
Python: cv.COLOR_YUV2GRAY_UYVY
COLOR_YUV2GRAY_YUY2 
Python: cv.COLOR_YUV2GRAY_YUY2
COLOR_YUV2GRAY_Y422 
Python: cv.COLOR_YUV2GRAY_Y422
COLOR_YUV2GRAY_UYNV 
Python: cv.COLOR_YUV2GRAY_UYNV
COLOR_YUV2GRAY_YVYU 
Python: cv.COLOR_YUV2GRAY_YVYU
COLOR_YUV2GRAY_YUYV 
Python: cv.COLOR_YUV2GRAY_YUYV
COLOR_YUV2GRAY_YUNV 
Python: cv.COLOR_YUV2GRAY_YUNV
COLOR_RGBA2mRGBA 
Python: cv.COLOR_RGBA2mRGBA

alpha premultiplication

COLOR_mRGBA2RGBA 
Python: cv.COLOR_mRGBA2RGBA
COLOR_RGB2YUV_I420 
Python: cv.COLOR_RGB2YUV_I420

RGB to YUV 4:2:0 family.

COLOR_BGR2YUV_I420 
Python: cv.COLOR_BGR2YUV_I420
COLOR_RGB2YUV_IYUV 
Python: cv.COLOR_RGB2YUV_IYUV
COLOR_BGR2YUV_IYUV 
Python: cv.COLOR_BGR2YUV_IYUV
COLOR_RGBA2YUV_I420 
Python: cv.COLOR_RGBA2YUV_I420
COLOR_BGRA2YUV_I420 
Python: cv.COLOR_BGRA2YUV_I420
COLOR_RGBA2YUV_IYUV 
Python: cv.COLOR_RGBA2YUV_IYUV
COLOR_BGRA2YUV_IYUV 
Python: cv.COLOR_BGRA2YUV_IYUV
COLOR_RGB2YUV_YV12 
Python: cv.COLOR_RGB2YUV_YV12
COLOR_BGR2YUV_YV12 
Python: cv.COLOR_BGR2YUV_YV12
COLOR_RGBA2YUV_YV12 
Python: cv.COLOR_RGBA2YUV_YV12
COLOR_BGRA2YUV_YV12 
Python: cv.COLOR_BGRA2YUV_YV12
COLOR_BayerBG2BGR 
Python: cv.COLOR_BayerBG2BGR

Demosaicing, see color conversions for additional information.

equivalent to RGGB Bayer pattern

COLOR_BayerGB2BGR 
Python: cv.COLOR_BayerGB2BGR

equivalent to GRBG Bayer pattern

COLOR_BayerRG2BGR 
Python: cv.COLOR_BayerRG2BGR

equivalent to BGGR Bayer pattern

COLOR_BayerGR2BGR 
Python: cv.COLOR_BayerGR2BGR

equivalent to GBRG Bayer pattern

COLOR_BayerRGGB2BGR 
Python: cv.COLOR_BayerRGGB2BGR
COLOR_BayerGRBG2BGR 
Python: cv.COLOR_BayerGRBG2BGR
COLOR_BayerBGGR2BGR 
Python: cv.COLOR_BayerBGGR2BGR
COLOR_BayerGBRG2BGR 
Python: cv.COLOR_BayerGBRG2BGR
COLOR_BayerRGGB2RGB 
Python: cv.COLOR_BayerRGGB2RGB
COLOR_BayerGRBG2RGB 
Python: cv.COLOR_BayerGRBG2RGB
COLOR_BayerBGGR2RGB 
Python: cv.COLOR_BayerBGGR2RGB
COLOR_BayerGBRG2RGB 
Python: cv.COLOR_BayerGBRG2RGB
COLOR_BayerBG2RGB 
Python: cv.COLOR_BayerBG2RGB

equivalent to RGGB Bayer pattern

COLOR_BayerGB2RGB 
Python: cv.COLOR_BayerGB2RGB

equivalent to GRBG Bayer pattern

COLOR_BayerRG2RGB 
Python: cv.COLOR_BayerRG2RGB

equivalent to BGGR Bayer pattern

COLOR_BayerGR2RGB 
Python: cv.COLOR_BayerGR2RGB

equivalent to GBRG Bayer pattern

COLOR_BayerBG2GRAY 
Python: cv.COLOR_BayerBG2GRAY

equivalent to RGGB Bayer pattern

COLOR_BayerGB2GRAY 
Python: cv.COLOR_BayerGB2GRAY

equivalent to GRBG Bayer pattern

COLOR_BayerRG2GRAY 
Python: cv.COLOR_BayerRG2GRAY

equivalent to BGGR Bayer pattern

COLOR_BayerGR2GRAY 
Python: cv.COLOR_BayerGR2GRAY

equivalent to GBRG Bayer pattern

COLOR_BayerRGGB2GRAY 
Python: cv.COLOR_BayerRGGB2GRAY
COLOR_BayerGRBG2GRAY 
Python: cv.COLOR_BayerGRBG2GRAY
COLOR_BayerBGGR2GRAY 
Python: cv.COLOR_BayerBGGR2GRAY
COLOR_BayerGBRG2GRAY 
Python: cv.COLOR_BayerGBRG2GRAY
COLOR_BayerBG2BGR_VNG 
Python: cv.COLOR_BayerBG2BGR_VNG

Demosaicing using Variable Number of Gradients.

equivalent to RGGB Bayer pattern

COLOR_BayerGB2BGR_VNG 
Python: cv.COLOR_BayerGB2BGR_VNG

equivalent to GRBG Bayer pattern

COLOR_BayerRG2BGR_VNG 
Python: cv.COLOR_BayerRG2BGR_VNG

equivalent to BGGR Bayer pattern

COLOR_BayerGR2BGR_VNG 
Python: cv.COLOR_BayerGR2BGR_VNG

equivalent to GBRG Bayer pattern

COLOR_BayerRGGB2BGR_VNG 
Python: cv.COLOR_BayerRGGB2BGR_VNG
COLOR_BayerGRBG2BGR_VNG 
Python: cv.COLOR_BayerGRBG2BGR_VNG
COLOR_BayerBGGR2BGR_VNG 
Python: cv.COLOR_BayerBGGR2BGR_VNG
COLOR_BayerGBRG2BGR_VNG 
Python: cv.COLOR_BayerGBRG2BGR_VNG
COLOR_BayerRGGB2RGB_VNG 
Python: cv.COLOR_BayerRGGB2RGB_VNG
COLOR_BayerGRBG2RGB_VNG 
Python: cv.COLOR_BayerGRBG2RGB_VNG
COLOR_BayerBGGR2RGB_VNG 
Python: cv.COLOR_BayerBGGR2RGB_VNG
COLOR_BayerGBRG2RGB_VNG 
Python: cv.COLOR_BayerGBRG2RGB_VNG
COLOR_BayerBG2RGB_VNG 
Python: cv.COLOR_BayerBG2RGB_VNG

equivalent to RGGB Bayer pattern

COLOR_BayerGB2RGB_VNG 
Python: cv.COLOR_BayerGB2RGB_VNG

equivalent to GRBG Bayer pattern

COLOR_BayerRG2RGB_VNG 
Python: cv.COLOR_BayerRG2RGB_VNG

equivalent to BGGR Bayer pattern

COLOR_BayerGR2RGB_VNG 
Python: cv.COLOR_BayerGR2RGB_VNG

equivalent to GBRG Bayer pattern

COLOR_BayerBG2BGR_EA 
Python: cv.COLOR_BayerBG2BGR_EA

Edge-Aware Demosaicing.

equivalent to RGGB Bayer pattern

COLOR_BayerGB2BGR_EA 
Python: cv.COLOR_BayerGB2BGR_EA

equivalent to GRBG Bayer pattern

COLOR_BayerRG2BGR_EA 
Python: cv.COLOR_BayerRG2BGR_EA

equivalent to BGGR Bayer pattern

COLOR_BayerGR2BGR_EA 
Python: cv.COLOR_BayerGR2BGR_EA

equivalent to GBRG Bayer pattern

COLOR_BayerRGGB2BGR_EA 
Python: cv.COLOR_BayerRGGB2BGR_EA
COLOR_BayerGRBG2BGR_EA 
Python: cv.COLOR_BayerGRBG2BGR_EA
COLOR_BayerBGGR2BGR_EA 
Python: cv.COLOR_BayerBGGR2BGR_EA
COLOR_BayerGBRG2BGR_EA 
Python: cv.COLOR_BayerGBRG2BGR_EA
COLOR_BayerRGGB2RGB_EA 
Python: cv.COLOR_BayerRGGB2RGB_EA
COLOR_BayerGRBG2RGB_EA 
Python: cv.COLOR_BayerGRBG2RGB_EA
COLOR_BayerBGGR2RGB_EA 
Python: cv.COLOR_BayerBGGR2RGB_EA
COLOR_BayerGBRG2RGB_EA 
Python: cv.COLOR_BayerGBRG2RGB_EA
COLOR_BayerBG2RGB_EA 
Python: cv.COLOR_BayerBG2RGB_EA

equivalent to RGGB Bayer pattern

COLOR_BayerGB2RGB_EA 
Python: cv.COLOR_BayerGB2RGB_EA

equivalent to GRBG Bayer pattern

COLOR_BayerRG2RGB_EA 
Python: cv.COLOR_BayerRG2RGB_EA

equivalent to BGGR Bayer pattern

COLOR_BayerGR2RGB_EA 
Python: cv.COLOR_BayerGR2RGB_EA

equivalent to GBRG Bayer pattern

COLOR_BayerBG2BGRA 
Python: cv.COLOR_BayerBG2BGRA

Demosaicing with alpha channel.

equivalent to RGGB Bayer pattern

COLOR_BayerGB2BGRA 
Python: cv.COLOR_BayerGB2BGRA

equivalent to GRBG Bayer pattern

COLOR_BayerRG2BGRA 
Python: cv.COLOR_BayerRG2BGRA

equivalent to BGGR Bayer pattern

COLOR_BayerGR2BGRA 
Python: cv.COLOR_BayerGR2BGRA

equivalent to GBRG Bayer pattern

COLOR_BayerRGGB2BGRA 
Python: cv.COLOR_BayerRGGB2BGRA
COLOR_BayerGRBG2BGRA 
Python: cv.COLOR_BayerGRBG2BGRA
COLOR_BayerBGGR2BGRA 
Python: cv.COLOR_BayerBGGR2BGRA
COLOR_BayerGBRG2BGRA 
Python: cv.COLOR_BayerGBRG2BGRA
COLOR_BayerRGGB2RGBA 
Python: cv.COLOR_BayerRGGB2RGBA
COLOR_BayerGRBG2RGBA 
Python: cv.COLOR_BayerGRBG2RGBA
COLOR_BayerBGGR2RGBA 
Python: cv.COLOR_BayerBGGR2RGBA
COLOR_BayerGBRG2RGBA 
Python: cv.COLOR_BayerGBRG2RGBA
COLOR_BayerBG2RGBA 
Python: cv.COLOR_BayerBG2RGBA

equivalent to RGGB Bayer pattern

COLOR_BayerGB2RGBA 
Python: cv.COLOR_BayerGB2RGBA

equivalent to GRBG Bayer pattern

COLOR_BayerRG2RGBA 
Python: cv.COLOR_BayerRG2RGBA

equivalent to BGGR Bayer pattern

COLOR_BayerGR2RGBA 
Python: cv.COLOR_BayerGR2RGBA

equivalent to GBRG Bayer pattern

COLOR_COLORCVT_MAX 
Python: cv.COLOR_COLORCVT_MAX

Function Documentation

◆ cvtColor()

void cv::cvtColor ( InputArray  src,
OutputArray  dst,
int  code,
int  dstCn = 0 
)
Python:
cv.cvtColor(src, code[, dst[, dstCn]]) -> dst

#include <opencv2/imgproc.hpp>

Converts an image from one color space to another.

The function converts an input image from one color space to another. In case of a transformation to-from RGB color space, the order of the channels should be specified explicitly (RGB or BGR). Note that the default color format in OpenCV is often referred to as RGB but it is actually BGR (the bytes are reversed). So the first byte in a standard (24-bit) color image will be an 8-bit Blue component, the second byte will be Green, and the third byte will be Red. The fourth, fifth, and sixth bytes would then be the second pixel (Blue, then Green, then Red), and so on.

The conventional ranges for R, G, and B channel values are:

  • 0 to 255 for CV_8U images
  • 0 to 65535 for CV_16U images
  • 0 to 1 for CV_32F images

In case of linear transformations, the range does not matter. But in case of a non-linear transformation, an input RGB image should be normalized to the proper value range to get the correct results, for example, for RGB \(\rightarrow\) L*u*v* transformation. For example, if you have a 32-bit floating-point image directly converted from an 8-bit image without any scaling, then it will have the 0..255 value range instead of 0..1 assumed by the function. So, before calling cvtColor , you need first to scale the image down:

img *= 1./255;

If you use cvtColor with 8-bit images, the conversion will have some information lost. For many applications, this will not be noticeable but it is recommended to use 32-bit images in applications that need the full range of colors or that convert an image before an operation and then convert back.

If conversion adds the alpha channel, its value will set to the maximum of corresponding channel range: 255 for CV_8U, 65535 for CV_16U, 1 for CV_32F.

Parameters
srcinput image: 8-bit unsigned, 16-bit unsigned ( CV_16UC... ), or single-precision floating-point.
dstoutput image of the same size and depth as src.
codecolor space conversion code (see ColorConversionCodes).
dstCnnumber of channels in the destination image; if the parameter is 0, the number of the channels is derived automatically from src and code.
See also
Color conversions
Examples:
samples/cpp/camshiftdemo.cpp, samples/cpp/edge.cpp, samples/cpp/facedetect.cpp, samples/cpp/ffilldemo.cpp, samples/cpp/lkdemo.cpp, samples/cpp/train_HOG.cpp, samples/cpp/tutorial_code/ImgTrans/houghcircles.cpp, samples/cpp/tutorial_code/ImgTrans/houghlines.cpp, samples/cpp/tutorial_code/ImgTrans/Sobel_Demo.cpp, samples/cpp/tutorial_code/ml/introduction_to_pca/introduction_to_pca.cpp, samples/cpp/watershed.cpp, samples/dnn/colorization.cpp, samples/dnn/text_detection.cpp, and samples/tapi/hog.cpp.

◆ cvtColorTwoPlane()

void cv::cvtColorTwoPlane ( InputArray  src1,
InputArray  src2,
OutputArray  dst,
int  code 
)
Python:
cv.cvtColorTwoPlane(src1, src2, code[, dst]) -> dst

#include <opencv2/imgproc.hpp>

Converts an image from one color space to another where the source image is stored in two planes.

This function only supports YUV420 to RGB conversion as of now.

Parameters
src18-bit image (CV_8U) of the Y plane.
src2image containing interleaved U/V plane.
dstoutput image.
codeSpecifies the type of conversion. It can take any of the following values:

◆ demosaicing()

void cv::demosaicing ( InputArray  src,
OutputArray  dst,
int  code,
int  dstCn = 0 
)
Python:
cv.demosaicing(src, code[, dst[, dstCn]]) -> dst

#include <opencv2/imgproc.hpp>

main function for all demosaicing processes

Parameters
srcinput image: 8-bit unsigned or 16-bit unsigned.
dstoutput image of the same size and depth as src.
codeColor space conversion code (see the description below).
dstCnnumber of channels in the destination image; if the parameter is 0, the number of the channels is derived automatically from src and code.

The function can do the following transformations:

See also
cvtColor