habana_frameworks.mediapipe.fn.Saturation

Class:

• habana_frameworks.mediapipe.fn.Saturation(**kwargs)

Define graph call:

• __call__(input, saturation_level_tensor)

Parameter:

• input - Input tensor to operator. Supported dimensions: minimum = 4, maximum = 4. Supported data types: UINT8, UINT16.

• (optional) saturation_level_tensor - Tensor containing saturation level for each image in the batch. Supported dimensions: minimum = 1, maximum = 1. Supported data types: FLOAT32.

Description:

Saturation operator modifies the saturation level of an image by specified change factor. It applies the HSV space modification to an RGB value to get the modified RGB value.

Supported backend:

• HPU

Keyword Arguments

kwargs	Description
saturation_level	Change factor by which the saturation level of an image needs to be modified. Type: float Default: 0.0 Optional: yes
dtype	Output data type. Type: habana_frameworks.mediapipe.media_types.dtype Default: UINT8 Optional: yes Supported data type: UINT8 UINT16

Note

1. Input tensor and Output tensor must be of the same data type.

2. Input1 and output tensor should be in NCHW layout. Input2 is one dimensional tensor of size N.

3. Saturation level can be provided either as scalar for all batches or 1D tensor.

4. Number of channels in input and output should be 3.

5. saturation_level should be >= 0

   • 0: completely de-saturated image

   • 1: no change to image’s saturation

Example: Saturation Operator

The following code snippet shows usage of Saturation operator:

from habana_frameworks.mediapipe import fn
from habana_frameworks.mediapipe.mediapipe import MediaPipe
from habana_frameworks.mediapipe.media_types import imgtype as it
from habana_frameworks.mediapipe.media_types import dtype as dt
import matplotlib.pyplot as plt

# Create media pipeline derived class
class myMediaPipe(MediaPipe):
    def __init__(self, device, dir, queue_depth, batch_size, img_h, img_w):
        super(
            myMediaPipe,
            self).__init__(
            device,
            queue_depth,
            batch_size,
            self.__class__.__name__)

        self.input = fn.ReadImageDatasetFromDir(shuffle=False,
                                                dir=dir,
                                                format="jpg")

        # WHCN
        self.decode = fn.ImageDecoder(device="hpu",
                                      output_format=it.RGB_P,
                                      resize=[img_w, img_h])

        self.saturation = fn.Saturation(saturation_level=0.3,
                                        dtype=dt.UINT8)

        # WHCN -> CWHN
        self.transpose = fn.Transpose(permutation=[2, 0, 1, 3],
                                      tensorDim=4,
                                      dtype=dt.UINT8)

    def definegraph(self):
        images, labels = self.input()
        images = self.decode(images)
        images = self.saturation(images)
        images = self.transpose(images)
        return images, labels

def display_images(images, batch_size, cols):
    rows = (batch_size + 1) // cols
    plt.figure(figsize=(10, 10))
    for i in range(batch_size):
        ax = plt.subplot(rows, cols, i + 1)
        plt.imshow(images[i])
        plt.axis("off")
    plt.show()

def main():
    batch_size = 6
    img_width = 200
    img_height = 200
    img_dir = "/path/to/images"
    queue_depth = 2
    columns = 3

    # Create media pipeline object
    pipe = myMediaPipe('hpu', img_dir, queue_depth, batch_size,
                        img_height, img_width)

    # Build media pipeline
    pipe.build()

    # Initialize media pipeline iterator
    pipe.iter_init()

    # Run media pipeline
    images, labels = pipe.run()

    # Copy data to host from device as numpy array
    images = images.as_cpu().as_nparray()
    labels = labels.as_cpu().as_nparray()

    # Display images
    display_images(images, batch_size, columns)


if __name__ == "__main__":
    main()

Images with Changed Saturation 1

1

Licensed under a CC BY SA 4.0 license. The images used here are taken from https://data.caltech.edu/records/mzrjq-6wc02.