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_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_BayerBG2BGR_VNG = 62,   cv::COLOR_BayerGB2BGR_VNG = 63,   cv::COLOR_BayerRG2BGR_VNG = 64,   cv::COLOR_BayerGR2BGR_VNG = 65,   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_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_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.
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.
void	cv::demosaicing (InputArray src, OutputArray dst, int code, int dstCn=0)
	main function for all demosaicing processes

Detailed Description

Enumeration Type Documentation

enum cv::ColorConversionCodes

the color conversion codes

See Also

Color conversions

Enumerator
COLOR_BGR2BGRA	add alpha channel to RGB or BGR image
COLOR_RGB2RGBA
COLOR_BGRA2BGR	remove alpha channel from RGB or BGR image
COLOR_RGBA2RGB
COLOR_BGR2RGBA	convert between RGB and BGR color spaces (with or without alpha channel)
COLOR_RGB2BGRA
COLOR_RGBA2BGR
COLOR_BGRA2RGB
COLOR_BGR2RGB
COLOR_RGB2BGR
COLOR_BGRA2RGBA
COLOR_RGBA2BGRA
COLOR_BGR2GRAY	convert between RGB/BGR and grayscale, color conversions
COLOR_RGB2GRAY
COLOR_GRAY2BGR
COLOR_GRAY2RGB
COLOR_GRAY2BGRA
COLOR_GRAY2RGBA
COLOR_BGRA2GRAY
COLOR_RGBA2GRAY
COLOR_BGR2BGR565	convert between RGB/BGR and BGR565 (16-bit images)
COLOR_RGB2BGR565
COLOR_BGR5652BGR
COLOR_BGR5652RGB
COLOR_BGRA2BGR565
COLOR_RGBA2BGR565
COLOR_BGR5652BGRA
COLOR_BGR5652RGBA
COLOR_GRAY2BGR565	convert between grayscale to BGR565 (16-bit images)
COLOR_BGR5652GRAY
COLOR_BGR2BGR555	convert between RGB/BGR and BGR555 (16-bit images)
COLOR_RGB2BGR555
COLOR_BGR5552BGR
COLOR_BGR5552RGB
COLOR_BGRA2BGR555
COLOR_RGBA2BGR555
COLOR_BGR5552BGRA
COLOR_BGR5552RGBA
COLOR_GRAY2BGR555	convert between grayscale and BGR555 (16-bit images)
COLOR_BGR5552GRAY
COLOR_BGR2XYZ	convert RGB/BGR to CIE XYZ, color conversions
COLOR_RGB2XYZ
COLOR_XYZ2BGR
COLOR_XYZ2RGB
COLOR_BGR2YCrCb	convert RGB/BGR to luma-chroma (aka YCC), color conversions
COLOR_RGB2YCrCb
COLOR_YCrCb2BGR
COLOR_YCrCb2RGB
COLOR_BGR2HSV	convert RGB/BGR to HSV (hue saturation value), color conversions
COLOR_RGB2HSV
COLOR_BGR2Lab	convert RGB/BGR to CIE Lab, color conversions
COLOR_RGB2Lab
COLOR_BGR2Luv	convert RGB/BGR to CIE Luv, color conversions
COLOR_RGB2Luv
COLOR_BGR2HLS	convert RGB/BGR to HLS (hue lightness saturation), color conversions
COLOR_RGB2HLS
COLOR_HSV2BGR	backward conversions to RGB/BGR
COLOR_HSV2RGB
COLOR_Lab2BGR
COLOR_Lab2RGB
COLOR_Luv2BGR
COLOR_Luv2RGB
COLOR_HLS2BGR
COLOR_HLS2RGB
COLOR_BGR2HSV_FULL
COLOR_RGB2HSV_FULL
COLOR_BGR2HLS_FULL
COLOR_RGB2HLS_FULL
COLOR_HSV2BGR_FULL
COLOR_HSV2RGB_FULL
COLOR_HLS2BGR_FULL
COLOR_HLS2RGB_FULL
COLOR_LBGR2Lab
COLOR_LRGB2Lab
COLOR_LBGR2Luv
COLOR_LRGB2Luv
COLOR_Lab2LBGR
COLOR_Lab2LRGB
COLOR_Luv2LBGR
COLOR_Luv2LRGB
COLOR_BGR2YUV	convert between RGB/BGR and YUV
COLOR_RGB2YUV
COLOR_YUV2BGR
COLOR_YUV2RGB
COLOR_YUV2RGB_NV12	YUV 4:2:0 family to RGB.
COLOR_YUV2BGR_NV12
COLOR_YUV2RGB_NV21
COLOR_YUV2BGR_NV21
COLOR_YUV420sp2RGB
COLOR_YUV420sp2BGR
COLOR_YUV2RGBA_NV12
COLOR_YUV2BGRA_NV12
COLOR_YUV2RGBA_NV21
COLOR_YUV2BGRA_NV21
COLOR_YUV420sp2RGBA
COLOR_YUV420sp2BGRA
COLOR_YUV2RGB_YV12
COLOR_YUV2BGR_YV12
COLOR_YUV2RGB_IYUV
COLOR_YUV2BGR_IYUV
COLOR_YUV2RGB_I420
COLOR_YUV2BGR_I420
COLOR_YUV420p2RGB
COLOR_YUV420p2BGR
COLOR_YUV2RGBA_YV12
COLOR_YUV2BGRA_YV12
COLOR_YUV2RGBA_IYUV
COLOR_YUV2BGRA_IYUV
COLOR_YUV2RGBA_I420
COLOR_YUV2BGRA_I420
COLOR_YUV420p2RGBA
COLOR_YUV420p2BGRA
COLOR_YUV2GRAY_420
COLOR_YUV2GRAY_NV21
COLOR_YUV2GRAY_NV12
COLOR_YUV2GRAY_YV12
COLOR_YUV2GRAY_IYUV
COLOR_YUV2GRAY_I420
COLOR_YUV420sp2GRAY
COLOR_YUV420p2GRAY
COLOR_YUV2RGB_UYVY	YUV 4:2:2 family to RGB.
COLOR_YUV2BGR_UYVY
COLOR_YUV2RGB_Y422
COLOR_YUV2BGR_Y422
COLOR_YUV2RGB_UYNV
COLOR_YUV2BGR_UYNV
COLOR_YUV2RGBA_UYVY
COLOR_YUV2BGRA_UYVY
COLOR_YUV2RGBA_Y422
COLOR_YUV2BGRA_Y422
COLOR_YUV2RGBA_UYNV
COLOR_YUV2BGRA_UYNV
COLOR_YUV2RGB_YUY2
COLOR_YUV2BGR_YUY2
COLOR_YUV2RGB_YVYU
COLOR_YUV2BGR_YVYU
COLOR_YUV2RGB_YUYV
COLOR_YUV2BGR_YUYV
COLOR_YUV2RGB_YUNV
COLOR_YUV2BGR_YUNV
COLOR_YUV2RGBA_YUY2
COLOR_YUV2BGRA_YUY2
COLOR_YUV2RGBA_YVYU
COLOR_YUV2BGRA_YVYU
COLOR_YUV2RGBA_YUYV
COLOR_YUV2BGRA_YUYV
COLOR_YUV2RGBA_YUNV
COLOR_YUV2BGRA_YUNV
COLOR_YUV2GRAY_UYVY
COLOR_YUV2GRAY_YUY2
COLOR_YUV2GRAY_Y422
COLOR_YUV2GRAY_UYNV
COLOR_YUV2GRAY_YVYU
COLOR_YUV2GRAY_YUYV
COLOR_YUV2GRAY_YUNV
COLOR_RGBA2mRGBA	alpha premultiplication
COLOR_mRGBA2RGBA
COLOR_RGB2YUV_I420	RGB to YUV 4:2:0 family.
COLOR_BGR2YUV_I420
COLOR_RGB2YUV_IYUV
COLOR_BGR2YUV_IYUV
COLOR_RGBA2YUV_I420
COLOR_BGRA2YUV_I420
COLOR_RGBA2YUV_IYUV
COLOR_BGRA2YUV_IYUV
COLOR_RGB2YUV_YV12
COLOR_BGR2YUV_YV12
COLOR_RGBA2YUV_YV12
COLOR_BGRA2YUV_YV12
COLOR_BayerBG2BGR	Demosaicing.
COLOR_BayerGB2BGR
COLOR_BayerRG2BGR
COLOR_BayerGR2BGR
COLOR_BayerBG2RGB
COLOR_BayerGB2RGB
COLOR_BayerRG2RGB
COLOR_BayerGR2RGB
COLOR_BayerBG2GRAY
COLOR_BayerGB2GRAY
COLOR_BayerRG2GRAY
COLOR_BayerGR2GRAY
COLOR_BayerBG2BGR_VNG	Demosaicing using Variable Number of Gradients.
COLOR_BayerGB2BGR_VNG
COLOR_BayerRG2BGR_VNG
COLOR_BayerGR2BGR_VNG
COLOR_BayerBG2RGB_VNG
COLOR_BayerGB2RGB_VNG
COLOR_BayerRG2RGB_VNG
COLOR_BayerGR2RGB_VNG
COLOR_BayerBG2BGR_EA	Edge-Aware Demosaicing.
COLOR_BayerGB2BGR_EA
COLOR_BayerRG2BGR_EA
COLOR_BayerGR2BGR_EA
COLOR_BayerBG2RGB_EA
COLOR_BayerGB2RGB_EA
COLOR_BayerRG2RGB_EA
COLOR_BayerGR2RGB_EA
COLOR_BayerBG2BGRA	Demosaicing with alpha channel.
COLOR_BayerGB2BGRA
COLOR_BayerRG2BGRA
COLOR_BayerGR2BGRA
COLOR_BayerBG2RGBA
COLOR_BayerGB2RGBA
COLOR_BayerRG2RGBA
COLOR_BayerGR2RGBA
COLOR_COLORCVT_MAX

Function Documentation

void cv::cvtColor	(	InputArray	src,
		OutputArray	dst,
		int	code,
		int	dstCn = 0
	)

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;
cvtColor(img, img, COLOR_BGR2Luv);

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

src	input image: 8-bit unsigned, 16-bit unsigned ( CV_16UC... ), or single-precision floating-point.
dst	output image of the same size and depth as src.
code	color space conversion code (see ColorConversionCodes).
dstCn	number 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, and samples/tapi/hog.cpp.

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.

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

Parameters

src1,:	8-bit image (CV_8U) of the Y plane.
src2,:	image containing interleaved U/V plane.
dst,:	output image.
code,:	Specifies the type of conversion. It can take any of the following values: COLOR_YUV2BGR_NV12 COLOR_YUV2RGB_NV12 COLOR_YUV2BGRA_NV12 COLOR_YUV2RGBA_NV12 COLOR_YUV2BGR_NV21 COLOR_YUV2RGB_NV21 COLOR_YUV2BGRA_NV21 COLOR_YUV2RGBA_NV21

void cv::demosaicing	(	InputArray	src,
		OutputArray	dst,
		int	code,
		int	dstCn = 0
	)

main function for all demosaicing processes

Parameters

src	input image: 8-bit unsigned or 16-bit unsigned.
dst	output image of the same size and depth as src.
code	Color space conversion code (see the description below).
dstCn	number 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:

• Demosaicing using bilinear interpolation

  COLOR_BayerBG2BGR , COLOR_BayerGB2BGR , COLOR_BayerRG2BGR , COLOR_BayerGR2BGR

  COLOR_BayerBG2GRAY , COLOR_BayerGB2GRAY , COLOR_BayerRG2GRAY , COLOR_BayerGR2GRAY

• Demosaicing using Variable Number of Gradients.

  COLOR_BayerBG2BGR_VNG , COLOR_BayerGB2BGR_VNG , COLOR_BayerRG2BGR_VNG , COLOR_BayerGR2BGR_VNG

• Edge-Aware Demosaicing.

  COLOR_BayerBG2BGR_EA , COLOR_BayerGB2BGR_EA , COLOR_BayerRG2BGR_EA , COLOR_BayerGR2BGR_EA

• Demosaicing with alpha channel

  COLOR_BayerBG2BGRA , COLOR_BayerGB2BGRA , COLOR_BayerRG2BGRA , COLOR_BayerGR2BGRA

See Also

cvtColor