Albumentations using single CPU core

[neel04]

Does albumentation not support multiprocessing? I had thought it did 🤔
This is HTOP output,

Maybe there are some transformations that prevent from using multi-threaded ops?

def get_train_transforms(height: int = 256, 
                         width: int = 256, 
                         level: str = 'hard'): 
    if level == 'light':
        return A.Compose([
                A.HorizontalFlip(p=0.5),
                A.IAAAdditiveGaussianNoise(p=0.2),
                A.OneOf(
                    [A.CLAHE(p=1.0),
                    A.RandomBrightness(p=1.0),
                    A.RandomGamma(p=1.0),
                    ],p=0.5),
                A.OneOf(
                    [A.IAASharpen(p=1.0),
                    A.Blur(blur_limit=3, p=1.0),
                    A.MotionBlur(blur_limit=3, p=1.0),
                    ],p=0.5),
                A.OneOf(
                    [A.RandomContrast(p=1.0),
                    A.HueSaturationValue(p=1.0),
                    ],p=0.5),
                A.Resize(height=height, width=width, p=1.0),
                A.PadIfNeeded(pad_to_multiple(height), 
                              pad_to_multiple(width), 
                              border_mode=cv2.BORDER_CONSTANT, 
                              value=0, 
                              mask_value=0)
            ], p=1.0)

    elif level == 'hard':
        return A.Compose([
                A.HorizontalFlip(p=0.5),
                A.IAAAdditiveGaussianNoise(p=0.2),
                A.OneOf(
                    [A.GridDistortion(border_mode=cv2.BORDER_CONSTANT, value=0, mask_value=0, p=1.0),
                     A.ElasticTransform(alpha_affine=10, border_mode=cv2.BORDER_CONSTANT, value=0, mask_value=0, p=1.0),
                     A.ShiftScaleRotate(
                         shift_limit=0,
                         scale_limit=0,
                         rotate_limit=10,
                         border_mode=cv2.BORDER_CONSTANT,
                         value=0,
                         mask_value=0,
                         p=1.0
                     ),
                     A.OpticalDistortion(border_mode=cv2.BORDER_CONSTANT, value=0, mask_value=0, p=1.0),
                    ],p=0.5),
                A.OneOf(
                    [A.CLAHE(p=1.0),
                    A.RandomBrightness(p=1.0),
                    A.RandomGamma(p=1.0),
                    A.ISONoise(p=1.0)
                    ],p=0.5),
                A.OneOf(
                    [A.IAASharpen(p=1.0),
                    A.Blur(blur_limit=3, p=1.0),
                    A.MotionBlur(blur_limit=3, p=1.0),
                    ],p=0.5),
                A.OneOf(
                    [A.RandomContrast(p=1.0),
                    A.HueSaturationValue(p=1.0),
                    ],p=0.5),
                A.Resize(height=height, width=width, p=1.0),
                #A.Cutout(p=0.3),
                A.PadIfNeeded(pad_to_multiple(height), 
                              pad_to_multiple(width), 
                              border_mode=cv2.BORDER_CONSTANT, 
                              value=0, 
                              mask_value=0) 
            ], p=1.0)
    elif level == 'hard_weather':
        return A.Compose([
                A.HorizontalFlip(p=0.5),
                A.IAAAdditiveGaussianNoise(p=0.2),
                A.OneOf(
                    [A.GridDistortion(border_mode=cv2.BORDER_CONSTANT, value=0, mask_value=0, p=1.0),
                     A.ElasticTransform(alpha_affine=10, border_mode=cv2.BORDER_CONSTANT, value=0, mask_value=0, p=1.0),
                     A.ShiftScaleRotate(
                         shift_limit=0,
                         scale_limit=0,
                         rotate_limit=10,
                         border_mode=cv2.BORDER_CONSTANT,
                         value=0,
                         mask_value=0,
                         p=1.0
                     ),
                     A.OpticalDistortion(border_mode=cv2.BORDER_CONSTANT, value=0, mask_value=0, p=1.0),
                    ],p=0.5),
                A.OneOf(
                    [A.CLAHE(p=1.0),
                    A.RandomBrightness(p=1.0),
                    A.RandomGamma(p=1.0),
                    A.ISONoise(p=1.0)
                    ],p=0.5),
                A.OneOf(
                    [A.IAASharpen(p=1.0),
                    A.Blur(blur_limit=3, p=1.0),
                    A.MotionBlur(blur_limit=3, p=1.0),
                    ],p=0.5),
                A.OneOf(
                    [A.RandomContrast(p=1.0),
                    A.HueSaturationValue(p=1.0),
                    ],p=0.5),
                A.OneOf(
                    [A.RandomFog(fog_coef_upper=0.8, p=1.0),
                     A.RandomRain(p=1.0),
                     A.RandomSnow(p=1.0),
                     A.RandomSunFlare(src_radius=100, p=1.0)
                    ],p=0.4),
                A.Resize(height=height, width=width, p=1.0),
                #A.Cutout(p=0.3),
                A.PadIfNeeded(pad_to_multiple(height), 
                              pad_to_multiple(width), 
                              border_mode=cv2.BORDER_CONSTANT, 
                              value=0, 
                              mask_value=0) 
            ], p=1.0)