Detection-of-plant-diseases/dataset/dataset.py

76 lines
2.6 KiB
Python

import os
from pathlib import Path
import tensorflow as tf
from .consts import DISEASE_CLASSES, PLANT_CLASSES
class Dataset:
''' Class to load and preprocess the dataset.
Loads images and labels from the given directory to tf.data.Dataset.
Args:
`data_dir (Path)`: Path to the dataset directory.
`seed (int)`: Seed for shuffling the dataset.
`repeat (int)`: Number of times to repeat the dataset.
`shuffle_buffer_size (int)`: Size of the buffer for shuffling the dataset.
`batch_size (int)`: Batch size for the dataset.
'''
def __init__(self,
data_dir: Path,
seed: int = 42,
repeat: int = 1,
shuffle_buffer_size: int = 10_000,
batch_size: int = 64) -> None:
self.data_dir = data_dir
self.seed = seed
self.repeat = repeat
self.shuffle_buffer_size = shuffle_buffer_size
self.batch_size = batch_size
self.dataset = self.__load_dataset()\
.shuffle(self.shuffle_buffer_size, seed=self.seed)\
.repeat(self.repeat)\
.batch(self.batch_size, drop_remainder=True)\
.prefetch(tf.data.experimental.AUTOTUNE)
def __load_dataset(self) -> tf.data.Dataset:
# check if path has 'test' word in it
dataset = tf.data.Dataset.list_files(str(self.data_dir / '*/*'))
if 'test' in str(self.data_dir).lower():
# file names issue - labels have camel case (regex?) and differs from the train/valid sets
pass
else:
dataset = dataset.map(
self.__preprocess, num_parallel_calls=tf.data.experimental.AUTOTUNE)
return dataset
def __get_labels(self, image_path):
path = tf.strings.split(image_path, os.path.sep)[-2]
plant = tf.strings.split(path, '___')[0]
disease = tf.strings.split(path, '___')[1]
one_hot_plant = plant == PLANT_CLASSES
one_hot_disease = disease == DISEASE_CLASSES
return tf.cast(one_hot_plant, dtype=tf.uint8, name=None), tf.cast(one_hot_disease, dtype=tf.uint8, name=None)
def __get_image(self, image_path):
img = tf.io.read_file(image_path)
img = tf.io.decode_jpeg(img, channels=3)
return tf.cast(img, dtype=tf.float32, name=None) / 255.
def __preprocess(self, image_path):
labels = self.__get_labels(image_path)
image = self.__get_image(image_path)
# returns X, Y1, Y2
return image, labels[0], labels[1]
def __getattr__(self, attr):
return getattr(self.dataset, attr)