Esempio n. 1
0
    def train_books(self, books, output_model_prefix, weights=None, train_to_val=1,
                    max_iters=100000, display=500, checkpoint_frequency=-1, preload=False):
        if isinstance(books, str):
            books = [books]
        dset = Nash5DataSet(DataSetMode.TRAIN, self.cachefile, books)
        if 0 < train_to_val < 1:
            valsamples = random.sample(dset._samples,
                                       int((1-train_to_val)*len(dset)))
            for s in valsamples:
                dset._samples.remove(s)
            vdset = Nash5DataSet(DataSetMode.TRAIN, self.cachefile, [])
            vdset._samples = valsamples
        else:
            vdset = None

        parser = argparse.ArgumentParser()
        setup_train_args(parser, omit=["files", "validation"])
        args = parser.parse_known_args()[0]
        with h5py.File(self.cachefile, 'r', libver='latest', swmr=True) as cache:
            if all(cache[b].attrs.get("dir") == "rtl" for b in books):
                args.bidi_dir = "rtl"
        params = params_from_args(args)
        params.output_model_prefix = output_model_prefix
        params.early_stopping_best_model_prefix = "best_" + output_model_prefix
        params.max_iters = max_iters
        params.display = display
        params.checkpoint_frequency = checkpoint_frequency

        trainer = Trainer(params, dset, txt_preproc=NoopTextProcessor(), data_preproc=NoopDataPreprocessor(),
                  validation_dataset=vdset, weights=weights, preload_training=preload, preload_validation=True)

        trainer.train(progress_bar=True)
Esempio n. 2
0
def run(cfg: CfgNode):

    # check if loading a json file
    if len(cfg.DATASET.TRAIN.PATH) == 1 and cfg.DATASET.TRAIN.PATH[0].endswith(
            "json"):
        import json
        with open(cfg.DATASET.TRAIN.PATH[0], 'r') as f:
            json_args = json.load(f)
            for key, value in json_args.items():
                if key == 'dataset' or key == 'validation_dataset':
                    setattr(cfg, key, DataSetType.from_string(value))
                else:
                    setattr(cfg, key, value)

    # parse whitelist
    whitelist = cfg.MODEL.CODEX.WHITELIST
    if len(whitelist) == 1:
        whitelist = list(whitelist[0])

    whitelist_files = glob_all(cfg.MODEL.CODEX.WHITELIST_FILES)
    for f in whitelist_files:
        with open(f) as txt:
            whitelist += list(txt.read())

    if cfg.DATASET.TRAIN.GT_EXTENSION is False:
        cfg.DATASET.TRAIN.GT_EXTENSION = DataSetType.gt_extension(
            cfg.DATASET.TRAIN.TYPE)

    if cfg.DATASET.VALID.GT_EXTENSION is False:
        cfg.DATASET.VALID.GT_EXTENSION = DataSetType.gt_extension(
            cfg.DATASET.VALID.TYPE)

    text_generator_params = TextGeneratorParameters()

    line_generator_params = LineGeneratorParameters()

    dataset_args = {
        'line_generator_params': line_generator_params,
        'text_generator_params': text_generator_params,
        'pad': None,
        'text_index': 0,
    }

    # Training dataset
    dataset = create_train_dataset(cfg, dataset_args)

    # Validation dataset
    validation_dataset_list = create_test_dataset(cfg, dataset_args)

    params = CheckpointParams()

    params.max_iters = cfg.SOLVER.MAX_ITER
    params.stats_size = cfg.STATS_SIZE
    params.batch_size = cfg.SOLVER.BATCH_SIZE
    params.checkpoint_frequency = cfg.SOLVER.CHECKPOINT_FREQ if cfg.SOLVER.CHECKPOINT_FREQ >= 0 else cfg.SOLVER.EARLY_STOPPING_FREQ
    params.output_dir = cfg.OUTPUT_DIR
    params.output_model_prefix = cfg.OUTPUT_MODEL_PREFIX
    params.display = cfg.DISPLAY
    params.skip_invalid_gt = not cfg.DATALOADER.NO_SKIP_INVALID_GT
    params.processes = cfg.NUM_THREADS
    params.data_aug_retrain_on_original = not cfg.DATALOADER.ONLY_TRAIN_ON_AUGMENTED

    params.early_stopping_at_acc = cfg.SOLVER.EARLY_STOPPING_AT_ACC
    params.early_stopping_frequency = cfg.SOLVER.EARLY_STOPPING_FREQ
    params.early_stopping_nbest = cfg.SOLVER.EARLY_STOPPING_NBEST
    params.early_stopping_best_model_prefix = cfg.EARLY_STOPPING_BEST_MODEL_PREFIX
    params.early_stopping_best_model_output_dir = \
        cfg.EARLY_STOPPING_BEST_MODEL_OUTPUT_DIR if cfg.EARLY_STOPPING_BEST_MODEL_OUTPUT_DIR else cfg.OUTPUT_DIR

    if cfg.INPUT.DATA_PREPROCESSING is False or len(
            cfg.INPUT.DATA_PREPROCESSING) == 0:
        cfg.INPUT.DATA_PREPROCESSING = [
            DataPreprocessorParams.DEFAULT_NORMALIZER
        ]

    params.model.data_preprocessor.type = DataPreprocessorParams.MULTI_NORMALIZER
    for preproc in cfg.INPUT.DATA_PREPROCESSING:
        pp = params.model.data_preprocessor.children.add()
        pp.type = DataPreprocessorParams.Type.Value(preproc) if isinstance(
            preproc, str) else preproc
        pp.line_height = cfg.INPUT.LINE_HEIGHT
        pp.pad = cfg.INPUT.PAD

    # Text pre processing (reading)
    params.model.text_preprocessor.type = TextProcessorParams.MULTI_NORMALIZER
    default_text_normalizer_params(
        params.model.text_preprocessor.children.add(),
        default=cfg.INPUT.TEXT_NORMALIZATION)
    default_text_regularizer_params(
        params.model.text_preprocessor.children.add(),
        groups=cfg.INPUT.TEXT_REGULARIZATION)
    strip_processor_params = params.model.text_preprocessor.children.add()
    strip_processor_params.type = TextProcessorParams.STRIP_NORMALIZER

    # Text post processing (prediction)
    params.model.text_postprocessor.type = TextProcessorParams.MULTI_NORMALIZER
    default_text_normalizer_params(
        params.model.text_postprocessor.children.add(),
        default=cfg.INPUT.TEXT_NORMALIZATION)
    default_text_regularizer_params(
        params.model.text_postprocessor.children.add(),
        groups=cfg.INPUT.TEXT_REGULARIZATION)
    strip_processor_params = params.model.text_postprocessor.children.add()
    strip_processor_params.type = TextProcessorParams.STRIP_NORMALIZER

    if cfg.SEED > 0:
        params.model.network.backend.random_seed = cfg.SEED

    if cfg.INPUT.BIDI_DIR:
        # change bidirectional text direction if desired
        bidi_dir_to_enum = {
            "rtl": TextProcessorParams.BIDI_RTL,
            "ltr": TextProcessorParams.BIDI_LTR,
            "auto": TextProcessorParams.BIDI_AUTO
        }

        bidi_processor_params = params.model.text_preprocessor.children.add()
        bidi_processor_params.type = TextProcessorParams.BIDI_NORMALIZER
        bidi_processor_params.bidi_direction = bidi_dir_to_enum[
            cfg.INPUT.BIDI_DIR]

        bidi_processor_params = params.model.text_postprocessor.children.add()
        bidi_processor_params.type = TextProcessorParams.BIDI_NORMALIZER
        bidi_processor_params.bidi_direction = TextProcessorParams.BIDI_AUTO

    params.model.line_height = cfg.INPUT.LINE_HEIGHT
    params.model.network.learning_rate = cfg.SOLVER.LR
    params.model.network.lr_decay = cfg.SOLVER.LR_DECAY
    params.model.network.lr_decay_freq = cfg.SOLVER.LR_DECAY_FREQ
    params.model.network.train_last_n_layer = cfg.SOLVER.TRAIN_LAST_N_LAYER
    network_params_from_definition_string(cfg.MODEL.NETWORK,
                                          params.model.network)
    params.model.network.clipping_norm = cfg.SOLVER.GRADIENT_CLIPPING_NORM
    params.model.network.backend.num_inter_threads = 0
    params.model.network.backend.num_intra_threads = 0
    params.model.network.backend.shuffle_buffer_size = cfg.DATALOADER.SHUFFLE_BUFFER_SIZE

    if cfg.MODEL.WEIGHTS == "":
        weights = None
    else:
        weights = cfg.MODEL.WEIGHTS

    # create the actual trainer
    trainer = Trainer(
        params,
        dataset,
        validation_dataset=validation_dataset_list,
        data_augmenter=SimpleDataAugmenter(),
        n_augmentations=cfg.INPUT.N_AUGMENT,
        weights=weights,
        codec_whitelist=whitelist,
        keep_loaded_codec=cfg.MODEL.CODEX.KEEP_LOADED_CODEC,
        preload_training=not cfg.DATALOADER.TRAIN_ON_THE_FLY,
        preload_validation=not cfg.DATALOADER.VALID_ON_THE_FLY,
    )
    trainer.train(auto_compute_codec=not cfg.MODEL.CODEX.SEE_WHITELIST,
                  progress_bar=not cfg.NO_PROGRESS_BAR)
Esempio n. 3
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def run(args):

    # check if loading a json file
    if len(args.files) == 1 and args.files[0].endswith("json"):
        import json
        with open(args.files[0], 'r') as f:
            json_args = json.load(f)
            for key, value in json_args.items():
                if key == 'dataset' or key == 'validation_dataset':
                    setattr(args, key, DataSetType.from_string(value))
                else:
                    setattr(args, key, value)

    # parse whitelist
    whitelist = args.whitelist
    if len(whitelist) == 1:
        whitelist = list(whitelist[0])

    whitelist_files = glob_all(args.whitelist_files)
    for f in whitelist_files:
        with open(f) as txt:
            whitelist += list(txt.read())

    if args.gt_extension is None:
        args.gt_extension = DataSetType.gt_extension(args.dataset)

    if args.validation_extension is None:
        args.validation_extension = DataSetType.gt_extension(args.validation_dataset)

    if args.text_generator_params is not None:
        with open(args.text_generator_params, 'r') as f:
            args.text_generator_params = json_format.Parse(f.read(), TextGeneratorParameters())
    else:
        args.text_generator_params = TextGeneratorParameters()

    if args.line_generator_params is not None:
        with open(args.line_generator_params, 'r') as f:
            args.line_generator_params = json_format.Parse(f.read(), LineGeneratorParameters())
    else:
        args.line_generator_params = LineGeneratorParameters()

    dataset_args = {
        'line_generator_params': args.line_generator_params,
        'text_generator_params': args.text_generator_params,
        'pad': args.dataset_pad,
        'text_index': args.pagexml_text_index,
    }

    # Training dataset
    dataset = create_train_dataset(args, dataset_args)

    # Validation dataset
    if args.validation:
        print("Resolving validation files")
        validation_image_files = glob_all(args.validation)
        if not args.validation_text_files:
            val_txt_files = [split_all_ext(f)[0] + args.validation_extension for f in validation_image_files]
        else:
            val_txt_files = sorted(glob_all(args.validation_text_files))
            validation_image_files, val_txt_files = keep_files_with_same_file_name(validation_image_files, val_txt_files)
            for img, gt in zip(validation_image_files, val_txt_files):
                if split_all_ext(os.path.basename(img))[0] != split_all_ext(os.path.basename(gt))[0]:
                    raise Exception("Expected identical basenames of validation file: {} and {}".format(img, gt))

        if len(set(val_txt_files)) != len(val_txt_files):
            raise Exception("Some validation images are occurring more than once in the data set.")

        validation_dataset = create_dataset(
            args.validation_dataset,
            DataSetMode.TRAIN,
            images=validation_image_files,
            texts=val_txt_files,
            skip_invalid=not args.no_skip_invalid_gt,
            args=dataset_args,
        )
        print("Found {} files in the validation dataset".format(len(validation_dataset)))
    else:
        validation_dataset = None

    params = CheckpointParams()

    params.max_iters = args.max_iters
    params.stats_size = args.stats_size
    params.batch_size = args.batch_size
    params.checkpoint_frequency = args.checkpoint_frequency if args.checkpoint_frequency >= 0 else args.early_stopping_frequency
    params.output_dir = args.output_dir
    params.output_model_prefix = args.output_model_prefix
    params.display = args.display
    params.skip_invalid_gt = not args.no_skip_invalid_gt
    params.processes = args.num_threads
    params.data_aug_retrain_on_original = not args.only_train_on_augmented

    params.early_stopping_frequency = args.early_stopping_frequency
    params.early_stopping_nbest = args.early_stopping_nbest
    params.early_stopping_best_model_prefix = args.early_stopping_best_model_prefix
    params.early_stopping_best_model_output_dir = \
        args.early_stopping_best_model_output_dir if args.early_stopping_best_model_output_dir else args.output_dir

    if args.data_preprocessing is None or len(args.data_preprocessing) == 0:
        args.data_preprocessing = [DataPreprocessorParams.DEFAULT_NORMALIZER]

    params.model.data_preprocessor.type = DataPreprocessorParams.MULTI_NORMALIZER
    for preproc in args.data_preprocessing:
        pp = params.model.data_preprocessor.children.add()
        pp.type = DataPreprocessorParams.Type.Value(preproc) if isinstance(preproc, str) else preproc
        pp.line_height = args.line_height
        pp.pad = args.pad

    # Text pre processing (reading)
    params.model.text_preprocessor.type = TextProcessorParams.MULTI_NORMALIZER
    default_text_normalizer_params(params.model.text_preprocessor.children.add(), default=args.text_normalization)
    default_text_regularizer_params(params.model.text_preprocessor.children.add(), groups=args.text_regularization)
    strip_processor_params = params.model.text_preprocessor.children.add()
    strip_processor_params.type = TextProcessorParams.STRIP_NORMALIZER

    # Text post processing (prediction)
    params.model.text_postprocessor.type = TextProcessorParams.MULTI_NORMALIZER
    default_text_normalizer_params(params.model.text_postprocessor.children.add(), default=args.text_normalization)
    default_text_regularizer_params(params.model.text_postprocessor.children.add(), groups=args.text_regularization)
    strip_processor_params = params.model.text_postprocessor.children.add()
    strip_processor_params.type = TextProcessorParams.STRIP_NORMALIZER

    if args.seed > 0:
        params.model.network.backend.random_seed = args.seed

    if args.bidi_dir:
        # change bidirectional text direction if desired
        bidi_dir_to_enum = {"rtl": TextProcessorParams.BIDI_RTL, "ltr": TextProcessorParams.BIDI_LTR,
                            "auto": TextProcessorParams.BIDI_AUTO}

        bidi_processor_params = params.model.text_preprocessor.children.add()
        bidi_processor_params.type = TextProcessorParams.BIDI_NORMALIZER
        bidi_processor_params.bidi_direction = bidi_dir_to_enum[args.bidi_dir]

        bidi_processor_params = params.model.text_postprocessor.children.add()
        bidi_processor_params.type = TextProcessorParams.BIDI_NORMALIZER
        bidi_processor_params.bidi_direction = TextProcessorParams.BIDI_AUTO

    params.model.line_height = args.line_height

    network_params_from_definition_string(args.network, params.model.network)
    params.model.network.clipping_mode = NetworkParams.ClippingMode.Value("CLIP_" + args.gradient_clipping_mode.upper())
    params.model.network.clipping_constant = args.gradient_clipping_const
    params.model.network.backend.fuzzy_ctc_library_path = args.fuzzy_ctc_library_path
    params.model.network.backend.num_inter_threads = args.num_inter_threads
    params.model.network.backend.num_intra_threads = args.num_intra_threads
    params.model.network.backend.shuffle_buffer_size = args.shuffle_buffer_size

    # create the actual trainer
    trainer = Trainer(params,
                      dataset,
                      validation_dataset=validation_dataset,
                      data_augmenter=SimpleDataAugmenter(),
                      n_augmentations=args.n_augmentations,
                      weights=args.weights,
                      codec_whitelist=whitelist,
                      keep_loaded_codec=args.keep_loaded_codec,
                      preload_training=not args.train_data_on_the_fly,
                      preload_validation=not args.validation_data_on_the_fly,
                      )
    trainer.train(
        auto_compute_codec=not args.no_auto_compute_codec,
        progress_bar=not args.no_progress_bars
    )
Esempio n. 4
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def run(args):

    # check if loading a json file
    if len(args.files) == 1 and args.files[0].endswith("json"):
        import json
        with open(args.files[0], 'r') as f:
            json_args = json.load(f)
            for key, value in json_args.items():
                setattr(args, key, value)

    # parse whitelist
    whitelist = args.whitelist
    if len(whitelist) == 1:
        whitelist = list(whitelist[0])

    whitelist_files = glob_all(args.whitelist_files)
    for f in whitelist_files:
        with open(f) as txt:
            whitelist += list(txt.read())

    if args.gt_extension is None:
        args.gt_extension = DataSetType.gt_extension(args.dataset)

    if args.validation_extension is None:
        args.validation_extension = DataSetType.gt_extension(args.validation_dataset)

    # Training dataset
    print("Resolving input files")
    input_image_files = sorted(glob_all(args.files))
    if not args.text_files:
        gt_txt_files = [split_all_ext(f)[0] + args.gt_extension for f in input_image_files]
    else:
        gt_txt_files = sorted(glob_all(args.text_files))
        input_image_files, gt_txt_files = keep_files_with_same_file_name(input_image_files, gt_txt_files)
        for img, gt in zip(input_image_files, gt_txt_files):
            if split_all_ext(os.path.basename(img))[0] != split_all_ext(os.path.basename(gt))[0]:
                raise Exception("Expected identical basenames of file: {} and {}".format(img, gt))

    if len(set(gt_txt_files)) != len(gt_txt_files):
        raise Exception("Some image are occurring more than once in the data set.")

    dataset = create_dataset(
        args.dataset,
        DataSetMode.TRAIN,
        images=input_image_files,
        texts=gt_txt_files,
        skip_invalid=not args.no_skip_invalid_gt
    )
    print("Found {} files in the dataset".format(len(dataset)))

    # Validation dataset
    if args.validation:
        print("Resolving validation files")
        validation_image_files = glob_all(args.validation)
        if not args.validation_text_files:
            val_txt_files = [split_all_ext(f)[0] + args.validation_extension for f in validation_image_files]
        else:
            val_txt_files = sorted(glob_all(args.validation_text_files))
            validation_image_files, val_txt_files = keep_files_with_same_file_name(validation_image_files, val_txt_files)
            for img, gt in zip(validation_image_files, val_txt_files):
                if split_all_ext(os.path.basename(img))[0] != split_all_ext(os.path.basename(gt))[0]:
                    raise Exception("Expected identical basenames of validation file: {} and {}".format(img, gt))

        if len(set(val_txt_files)) != len(val_txt_files):
            raise Exception("Some validation images are occurring more than once in the data set.")

        validation_dataset = create_dataset(
            args.validation_dataset,
            DataSetMode.TRAIN,
            images=validation_image_files,
            texts=val_txt_files,
            skip_invalid=not args.no_skip_invalid_gt)
        print("Found {} files in the validation dataset".format(len(validation_dataset)))
    else:
        validation_dataset = None

    params = CheckpointParams()

    params.max_iters = args.max_iters
    params.stats_size = args.stats_size
    params.batch_size = args.batch_size
    params.checkpoint_frequency = args.checkpoint_frequency if args.checkpoint_frequency >= 0 else args.early_stopping_frequency
    params.output_dir = args.output_dir
    params.output_model_prefix = args.output_model_prefix
    params.display = args.display
    params.skip_invalid_gt = not args.no_skip_invalid_gt
    params.processes = args.num_threads
    params.data_aug_retrain_on_original = not args.only_train_on_augmented

    params.early_stopping_frequency = args.early_stopping_frequency
    params.early_stopping_nbest = args.early_stopping_nbest
    params.early_stopping_best_model_prefix = args.early_stopping_best_model_prefix
    params.early_stopping_best_model_output_dir = \
        args.early_stopping_best_model_output_dir if args.early_stopping_best_model_output_dir else args.output_dir

    params.model.data_preprocessor.type = DataPreprocessorParams.DEFAULT_NORMALIZER
    params.model.data_preprocessor.line_height = args.line_height
    params.model.data_preprocessor.pad = args.pad

    # Text pre processing (reading)
    params.model.text_preprocessor.type = TextProcessorParams.MULTI_NORMALIZER
    default_text_normalizer_params(params.model.text_preprocessor.children.add(), default=args.text_normalization)
    default_text_regularizer_params(params.model.text_preprocessor.children.add(), groups=args.text_regularization)
    strip_processor_params = params.model.text_preprocessor.children.add()
    strip_processor_params.type = TextProcessorParams.STRIP_NORMALIZER

    # Text post processing (prediction)
    params.model.text_postprocessor.type = TextProcessorParams.MULTI_NORMALIZER
    default_text_normalizer_params(params.model.text_postprocessor.children.add(), default=args.text_normalization)
    default_text_regularizer_params(params.model.text_postprocessor.children.add(), groups=args.text_regularization)
    strip_processor_params = params.model.text_postprocessor.children.add()
    strip_processor_params.type = TextProcessorParams.STRIP_NORMALIZER

    if args.seed > 0:
        params.model.network.backend.random_seed = args.seed

    if args.bidi_dir:
        # change bidirectional text direction if desired
        bidi_dir_to_enum = {"rtl": TextProcessorParams.BIDI_RTL, "ltr": TextProcessorParams.BIDI_LTR,
                            "auto": TextProcessorParams.BIDI_AUTO}

        bidi_processor_params = params.model.text_preprocessor.children.add()
        bidi_processor_params.type = TextProcessorParams.BIDI_NORMALIZER
        bidi_processor_params.bidi_direction = bidi_dir_to_enum[args.bidi_dir]

        bidi_processor_params = params.model.text_postprocessor.children.add()
        bidi_processor_params.type = TextProcessorParams.BIDI_NORMALIZER
        bidi_processor_params.bidi_direction = TextProcessorParams.BIDI_AUTO

    params.model.line_height = args.line_height

    network_params_from_definition_string(args.network, params.model.network)
    params.model.network.clipping_mode = NetworkParams.ClippingMode.Value("CLIP_" + args.gradient_clipping_mode.upper())
    params.model.network.clipping_constant = args.gradient_clipping_const
    params.model.network.backend.fuzzy_ctc_library_path = args.fuzzy_ctc_library_path
    params.model.network.backend.num_inter_threads = args.num_inter_threads
    params.model.network.backend.num_intra_threads = args.num_intra_threads

    # create the actual trainer
    trainer = Trainer(params,
                      dataset,
                      validation_dataset=validation_dataset,
                      data_augmenter=SimpleDataAugmenter(),
                      n_augmentations=args.n_augmentations,
                      weights=args.weights,
                      codec_whitelist=whitelist,
                      preload_training=not args.train_data_on_the_fly,
                      preload_validation=not args.validation_data_on_the_fly,
                      )
    trainer.train(
        auto_compute_codec=not args.no_auto_compute_codec,
        progress_bar=not args.no_progress_bars
    )
Esempio n. 5
0
def main():
    parser = argparse.ArgumentParser()
    setup_train_args(parser)
    args = parser.parse_args()

    # check if loading a json file
    if len(args.files) == 1 and args.files[0].endswith("json"):
        import json
        with open(args.files[0], 'r') as f:
            json_args = json.load(f)
            for key, value in json_args.items():
                setattr(args, key, value)

    # parse whitelist
    whitelist = args.whitelist
    whitelist_files = glob_all(args.whitelist_files)
    for f in whitelist_files:
        with open(f) as txt:
            whitelist += list(txt.read())

    # Training dataset
    print("Resolving input files")
    input_image_files = glob_all(args.files)
    gt_txt_files = [split_all_ext(f)[0] + ".gt.txt" for f in input_image_files]

    if len(set(gt_txt_files)) != len(gt_txt_files):
        raise Exception("Some image are occurring more than once in the data set.")

    dataset = FileDataSet(input_image_files, gt_txt_files, skip_invalid=not args.no_skip_invalid_gt)
    print("Found {} files in the dataset".format(len(dataset)))

    # Validation dataset
    if args.validation:
        print("Resolving validation files")
        validation_image_files = glob_all(args.validation)
        val_txt_files = [split_all_ext(f)[0] + ".gt.txt" for f in validation_image_files]

        if len(set(val_txt_files)) != len(val_txt_files):
            raise Exception("Some validation images are occurring more than once in the data set.")

        validation_dataset = FileDataSet(validation_image_files, val_txt_files,
                                         skip_invalid=not args.no_skip_invalid_gt)
        print("Found {} files in the validation dataset".format(len(validation_dataset)))
    else:
        validation_dataset = None

    params = CheckpointParams()

    params.max_iters = args.max_iters
    params.stats_size = args.stats_size
    params.batch_size = args.batch_size
    params.checkpoint_frequency = args.checkpoint_frequency
    params.output_dir = args.output_dir
    params.output_model_prefix = args.output_model_prefix
    params.display = args.display
    params.skip_invalid_gt = not args.no_skip_invalid_gt
    params.processes = args.num_threads

    params.early_stopping_frequency = args.early_stopping_frequency if args.early_stopping_frequency >= 0 else args.checkpoint_frequency
    params.early_stopping_nbest = args.early_stopping_nbest
    params.early_stopping_best_model_prefix = args.early_stopping_best_model_prefix
    params.early_stopping_best_model_output_dir = \
        args.early_stopping_best_model_output_dir if args.early_stopping_best_model_output_dir else args.output_dir

    params.model.data_preprocessor.type = DataPreprocessorParams.DEFAULT_NORMALIZER
    params.model.data_preprocessor.line_height = args.line_height
    params.model.data_preprocessor.pad = args.pad

    # Text pre processing (reading)
    params.model.text_preprocessor.type = TextProcessorParams.MULTI_NORMALIZER
    default_text_normalizer_params(params.model.text_preprocessor.children.add(), default=args.text_normalization)
    default_text_regularizer_params(params.model.text_preprocessor.children.add(), groups=args.text_regularization)
    strip_processor_params = params.model.text_preprocessor.children.add()
    strip_processor_params.type = TextProcessorParams.STRIP_NORMALIZER

    # Text post processing (prediction)
    params.model.text_postprocessor.type = TextProcessorParams.MULTI_NORMALIZER
    default_text_normalizer_params(params.model.text_postprocessor.children.add(), default=args.text_normalization)
    default_text_regularizer_params(params.model.text_postprocessor.children.add(), groups=args.text_regularization)
    strip_processor_params = params.model.text_postprocessor.children.add()
    strip_processor_params.type = TextProcessorParams.STRIP_NORMALIZER

    if args.seed > 0:
        params.model.network.backend.random_seed = args.seed

    if args.bidi_dir:
        # change bidirectional text direction if desired
        bidi_dir_to_enum = {"rtl": TextProcessorParams.BIDI_RTL, "ltr": TextProcessorParams.BIDI_LTR}

        bidi_processor_params = params.model.text_preprocessor.children.add()
        bidi_processor_params.type = TextProcessorParams.BIDI_NORMALIZER
        bidi_processor_params.bidi_direction = bidi_dir_to_enum[args.bidi_dir]

        bidi_processor_params = params.model.text_postprocessor.children.add()
        bidi_processor_params.type = TextProcessorParams.BIDI_NORMALIZER
        bidi_processor_params.bidi_direction = bidi_dir_to_enum[args.bidi_dir]

    params.model.line_height = args.line_height

    network_params_from_definition_string(args.network, params.model.network)
    params.model.network.clipping_mode = NetworkParams.ClippingMode.Value("CLIP_" + args.gradient_clipping_mode.upper())
    params.model.network.clipping_constant = args.gradient_clipping_const
    params.model.network.backend.fuzzy_ctc_library_path = args.fuzzy_ctc_library_path
    params.model.network.backend.num_inter_threads = args.num_inter_threads
    params.model.network.backend.num_intra_threads = args.num_intra_threads

    # create the actual trainer
    trainer = Trainer(params,
                      dataset,
                      validation_dataset=validation_dataset,
                      data_augmenter=SimpleDataAugmenter(),
                      n_augmentations=args.n_augmentations,
                      weights=args.weights,
                      codec_whitelist=whitelist,
                      )
    trainer.train(progress_bar=not args.no_progress_bars)