pytorch_data_preload.py

class RAMDataset(Dataset):
  def __init__(image_fnames, targets):
    self.targets = targets
    self.images = []
    for fname in tqdm(image_fnames, desc="Loading files in RAM"):
      with open(fname, "rb") as f:
        self.images.append(f.read())
    
  def __len__(self):
    return len(self.targets)
  
  def __getitem__(self, index):
    target = self.targets[index]
    image, retval = cv2.imdecode(self.images[index], cv2.IMREAD_COLOR)
    return image, target