Class ov::op::v8::NV12toBGR#

class NV12toBGR : public ov::op::util::ConvertColorNV12Base#

Color conversion operation from NV12 to RGB format. Input:

  • Input NV12 image can be represented in two ways: a) Single plane (as it is in the file): NV12 height dimension is 1.5x bigger than image height. ‘C’ dimension shall be 1. b) Two separate planes (used this way in many physical video sources): Y and UV. In this case b1) Y plane has height same as image height. ‘C’ dimension equals to 1 b2) UV plane has dimensions: ‘H’ = image_h / 2; ‘W’ = image_w / 2; ‘C’ = 2.

  • Supported element types: u8 or any supported floating-point type. Output:

  • Output node will have NHWC layout and shape HxW same as image spatial dimensions.

  • Number of output channels ‘C’ will be 3, as per interleaved RGB format, first channel is B, last is R

    Conversion of each pixel from NV12 (YUV) to RGB space is represented by following formulas: R = 1.164 * (Y - 16) + 1.596 * (V - 128) G = 1.164 * (Y - 16) - 0.813 * (V - 128) - 0.391 * (U - 128) B = 1.164 * (Y - 16) + 2.018 * (U - 128) Then R, G, B values are clipped to range (0, 255)

Public Functions

explicit NV12toBGR(const Output<Node> &arg)#

Constructs a conversion operation from input image in NV12 format As per NV12 format definition, node height dimension shall be 1.5 times bigger than image height so that image (w=640, h=480) is represented by NHWC shape {N,720,640,1} (height*1.5 x width)

Parameters:

arg – Node that produces the input tensor. Input tensor represents image in NV12 format (YUV).

explicit NV12toBGR(const Output<Node> &arg_y, const Output<Node> &arg_uv)#

Constructs a conversion operation from 2-plane input image in NV12 format In general case Y channel of image can be separated from UV channel which means that operation needs two nodes for Y and UV planes respectively. Y plane has one channel, and UV has 2 channels, both expect ‘NHWC’ layout.

Parameters:

  • arg_y – Node that produces the input tensor for Y plane (NHWC layout). Shall have WxH dimensions equal to image dimensions. ‘C’ dimension equals to 1.

  • arg_uv – Node that produces the input tensor for UV plane (NHWC layout). ‘H’ is half of image height, ‘W’ is half of image width, ‘C’ dimension equals to 2. Channel 0 represents ‘U’, channel 1 represents ‘V’ channel