Implement extraction command

Requires !9 (merged)

Closes #9 (closed)

Datasets/dataset_formatters/generic_dataset_formatter.py

-import os
-import shutil
-import tarfile
-import pickle
-import re
-from PIL import Image
-import numpy as np
-
-
-class DatasetFormatter:
-    """
-    Global pipeline/functions for dataset formatting
-    """
-
-    def __init__(self, dataset_name, level, extra_name="", set_names=["train", "valid", "test"]):
-        self.dataset_name = dataset_name
-        self.level = level
-        self.set_names = set_names
-        self.target_fold_path = os.path.join(
-            "Datasets", "formatted", "{}_{}{}".format(dataset_name, level, extra_name))
-        self.map_datasets_files = dict()
-        self.extract_with_dirname = False
-
-    def format(self):
-        self.init_format()
-        self.map_datasets_files[self.dataset_name][self.level]["format_function"]()
-        self.end_format()
-
-    def init_format(self):
-        """
-        Load and extracts needed files
-        """
-        os.makedirs(self.target_fold_path, exist_ok=True)
-
-        for set_name in self.set_names:
-            os.makedirs(os.path.join(self.target_fold_path, set_name), exist_ok=True)
-
-
-class OCRDatasetFormatter(DatasetFormatter):
-    """
-    Specific pipeline/functions for OCR/HTR dataset formatting
-    """
-
-    def __init__(self, source_dataset, level, extra_name="", set_names=["train", "valid", "test"]):
-        super(OCRDatasetFormatter, self).__init__(source_dataset, level, extra_name, set_names)
-        self.charset = set()
-        self.gt = dict()
-        for set_name in set_names:
-            self.gt[set_name] = dict()
-
-    def format_text_label(self, label):
-        """
-        Remove extra space or line break characters
-        """
-        temp = re.sub("(\n)+", '\n', label)
-        return re.sub("( )+", ' ', temp).strip(" \n")
-
-    def load_resize_save(self, source_path, target_path):
-        """
-        Load image, apply resolution modification and save it
-        """
-        shutil.copyfile(source_path, target_path)
-
-    def resize(self, img, source_dpi, target_dpi):
-        """
-        Apply resolution modification to image
-        """
-        if source_dpi == target_dpi:
-            return img
-        if isinstance(img, np.ndarray):
-            h, w = img.shape[:2]
-            img = Image.fromarray(img)
-        else:
-            w, h = img.size
-        ratio = target_dpi / source_dpi
-        img = img.resize((int(w*ratio), int(h*ratio)), Image.BILINEAR)
-        return np.array(img)
-
-    def end_format(self):
-        """
-        Save label and charset files
-        """
-        with open(os.path.join(self.target_fold_path, "labels.pkl"), "wb") as f:
-            pickle.dump({
-                "ground_truth": self.gt,
-                "charset": sorted(list(self.charset)),
-            }, f)
-        with open(os.path.join(self.target_fold_path, "charset.pkl"), "wb") as f:
-            pickle.dump(sorted(list(self.charset)), f)