basicsr.utils.color_util

basicsr.utils.color_util.bgr2ycbcr(img, y_only=False)

Convert a BGR image to YCbCr image.

The bgr version of rgb2ycbcr. It implements the ITU-R BT.601 conversion for standard-definition television. See more details in https://en.wikipedia.org/wiki/YCbCr#ITU-R_BT.601_conversion.

It differs from a similar function in cv2.cvtColor: BGR <-> YCrCb. In OpenCV, it implements a JPEG conversion. See more details in https://en.wikipedia.org/wiki/YCbCr#JPEG_conversion.

Parameters:

• img (ndarray) – The input image. It accepts: 1. np.uint8 type with range [0, 255]; 2. np.float32 type with range [0, 1].

• y_only (bool) – Whether to only return Y channel. Default: False.

Returns:

The converted YCbCr image. The output image has the same type

and range as input image.

Return type:

ndarray

basicsr.utils.color_util.rgb2ycbcr(img, y_only=False)

Convert a RGB image to YCbCr image.

This function produces the same results as Matlab’s rgb2ycbcr function. It implements the ITU-R BT.601 conversion for standard-definition television. See more details in https://en.wikipedia.org/wiki/YCbCr#ITU-R_BT.601_conversion.

It differs from a similar function in cv2.cvtColor: RGB <-> YCrCb. In OpenCV, it implements a JPEG conversion. See more details in https://en.wikipedia.org/wiki/YCbCr#JPEG_conversion.

Parameters:

• img (ndarray) – The input image. It accepts: 1. np.uint8 type with range [0, 255]; 2. np.float32 type with range [0, 1].

• y_only (bool) – Whether to only return Y channel. Default: False.

Returns:

The converted YCbCr image. The output image has the same type

and range as input image.

Return type:

ndarray

basicsr.utils.color_util.rgb2ycbcr_pt(img, y_only=False)

Convert RGB images to YCbCr images (PyTorch version).

It implements the ITU-R BT.601 conversion for standard-definition television. See more details in https://en.wikipedia.org/wiki/YCbCr#ITU-R_BT.601_conversion.

Parameters:

img (Tensor) – Images with shape (n, 3, h, w), the range [0, 1], float, RGB format. y_only (bool): Whether to only return Y channel. Default: False.

Returns:

converted images with the shape (n, 3/1, h, w), the range [0, 1], float.

Return type:

(Tensor)

basicsr.utils.color_util.ycbcr2bgr(img)

Convert a YCbCr image to BGR image.

The bgr version of ycbcr2rgb. It implements the ITU-R BT.601 conversion for standard-definition television. See more details in https://en.wikipedia.org/wiki/YCbCr#ITU-R_BT.601_conversion.

It differs from a similar function in cv2.cvtColor: YCrCb <-> BGR. In OpenCV, it implements a JPEG conversion. See more details in https://en.wikipedia.org/wiki/YCbCr#JPEG_conversion.

Parameters:

img (ndarray) – The input image. It accepts: 1. np.uint8 type with range [0, 255]; 2. np.float32 type with range [0, 1].

Returns:

The converted BGR image. The output image has the same type

and range as input image.

Return type:

ndarray

basicsr.utils.color_util.ycbcr2rgb(img)

Convert a YCbCr image to RGB image.

This function produces the same results as Matlab’s ycbcr2rgb function. It implements the ITU-R BT.601 conversion for standard-definition television. See more details in https://en.wikipedia.org/wiki/YCbCr#ITU-R_BT.601_conversion.

It differs from a similar function in cv2.cvtColor: YCrCb <-> RGB. In OpenCV, it implements a JPEG conversion. See more details in https://en.wikipedia.org/wiki/YCbCr#JPEG_conversion.

Parameters:

img (ndarray) – The input image. It accepts: 1. np.uint8 type with range [0, 255]; 2. np.float32 type with range [0, 1].

Returns:

The converted RGB image. The output image has the same type

and range as input image.

Return type:

ndarray