コード例 #1
0
def run(img_folder,
        img_height=1024,
        img_scale=4095,
        roi_per_img=32,
        roi_size=(256, 256),
        low_int_threshold=.05,
        blob_min_area=3,
        blob_min_int=.5,
        blob_max_int=.85,
        blob_th_step=10,
        roi_state=None,
        roi_bs=32,
        do_featurewise_norm=True,
        featurewise_mean=884.7,
        featurewise_std=745.3,
        img_tsv='./metadata/images_crosswalk_prediction.tsv',
        exam_tsv=None,
        dl_state=None,
        dl_bs=32,
        nb_top_avg=1,
        validation_mode=False,
        val_size=None,
        img_voting=False,
        out_pred='./output/predictions.tsv'):
    '''Run SC1 inference using the candidate ROI approach
    Notes: 
        "mean=884.7, std=745.3" are estimated from 20 subjects on the 
        training data.
    '''

    # Read some env variables.
    random_seed = int(os.getenv('RANDOM_SEED', 12345))
    # nb_worker = int(os.getenv('NUM_CPU_CORES', 4))
    gpu_count = int(os.getenv('NUM_GPU_DEVICES', 1))

    # Setup data generator for inference.
    meta_man = DMMetaManager(img_tsv=img_tsv,
                             exam_tsv=exam_tsv,
                             img_folder=img_folder,
                             img_extension='dcm')
    if val_size is not None:  # Use a subset for validation.
        subj_list, subj_labs = meta_man.get_subj_labs()
        _, subj_test = train_test_split(subj_list,
                                        test_size=val_size,
                                        random_state=random_seed,
                                        stratify=subj_labs)
    else:
        subj_test = None

    if validation_mode:
        exam_list = meta_man.get_flatten_exam_list(subj_list=subj_test,
                                                   flatten_img_list=True)
    else:
        exam_list = meta_man.get_last_exam_list(subj_list=subj_test,
                                                flatten_img_list=True)

    if do_featurewise_norm:
        img_gen = DMImageDataGenerator(featurewise_center=True,
                                       featurewise_std_normalization=True)
        img_gen.mean = featurewise_mean
        img_gen.std = featurewise_std
    else:
        img_gen = DMImageDataGenerator(samplewise_center=True,
                                       samplewise_std_normalization=True)
    if validation_mode:
        class_mode = 'categorical'
    else:
        class_mode = None

    # Load ROI classifier.
    if roi_state is not None:
        roi_clf = load_model(roi_state,
                             custom_objects={
                                 'sensitivity': DMMetrics.sensitivity,
                                 'specificity': DMMetrics.specificity
                             })
        if gpu_count > 1:
            roi_clf = make_parallel(roi_clf, gpu_count)
    else:
        roi_clf = None

    # Load model.
    if dl_state is not None:
        model = load_model(dl_state)
    else:
        raise Exception('At least one model state must be specified.')
    if gpu_count > 1:
        model = make_parallel(model, gpu_count)

    # A function to make predictions on image patches from an image list.
    def pred_img_list(img_list):
        roi_generator = img_gen.flow_from_candid_roi(
            img_list,
            target_height=img_height,
            target_scale=img_scale,
            class_mode=class_mode,
            validation_mode=True,
            img_per_batch=len(img_list),
            roi_per_img=roi_per_img,
            roi_size=roi_size,
            low_int_threshold=low_int_threshold,
            blob_min_area=blob_min_area,
            blob_min_int=blob_min_int,
            blob_max_int=blob_max_int,
            blob_th_step=blob_th_step,
            roi_clf=roi_clf,
            clf_bs=roi_bs,
            return_sample_weight=True,
            seed=random_seed)
        roi_dat, roi_w = roi_generator.next()
        # import pdb; pdb.set_trace()
        pred = model.predict(roi_dat, batch_size=dl_bs)
        pred = pred[:, 1]  # cancer class predictions.
        if roi_clf is not None:
            # return np.average(pred, weights=roi_w)
            # import pdb; pdb.set_trace()
            return pred[np.argsort(roi_w)[-nb_top_avg:]].mean()
        elif img_voting:
            pred = pred.reshape((-1, roi_per_img))
            img_preds = [np.sort(row)[-nb_top_avg:].mean() for row in pred]
            return np.mean(img_preds)
        else:
            return np.sort(pred)[-nb_top_avg:].mean()

    # Print header.
    fout = open(out_pred, 'w')
    if validation_mode:
        fout.write(dminfer.INFER_HEADER_VAL)
    else:
        fout.write(dminfer.INFER_HEADER)

    for subj, exidx, exam in exam_list:
        try:
            predL = pred_img_list(exam['L']['img'])
        except KeyError:
            predL = .0
        try:
            predR = pred_img_list(exam['R']['img'])
        except KeyError:
            predR = .0

        try:
            cancerL = int(exam['L']['cancer'])
        except ValueError:
            cancerL = 0
        try:
            cancerR = int(exam['R']['cancer'])
        except ValueError:
            cancerR = 0

        if validation_mode:
            fout.write("%s\t%s\tL\t%f\t%d\n" % \
                       (str(subj), str(exidx), predL, cancerL))
            fout.write("%s\t%s\tR\t%f\t%d\n" % \
                       (str(subj), str(exidx), predR, cancerR))
        else:
            fout.write("%s\tL\t%f\n" % (str(subj), predL))
            fout.write("%s\tR\t%f\n" % (str(subj), predR))

    fout.close()
コード例 #2
0
def run(img_folder, img_extension='dcm', 
        img_height=1024, img_scale=4095, 
        do_featurewise_norm=True, norm_fit_size=10,
        img_per_batch=2, roi_per_img=32, roi_size=(256, 256), 
        one_patch_mode=False,
        low_int_threshold=.05, blob_min_area=3, 
        blob_min_int=.5, blob_max_int=.85, blob_th_step=10,
        data_augmentation=False, roi_state=None, clf_bs=32, cutpoint=.5,
        amp_factor=1., return_sample_weight=True, auto_batch_balance=True,
        patches_per_epoch=12800, nb_epoch=20, 
        neg_vs_pos_ratio=None, all_neg_skip=0., 
        nb_init_filter=32, init_filter_size=5, init_conv_stride=2, 
        pool_size=2, pool_stride=2, 
        weight_decay=.0001, alpha=.0001, l1_ratio=.0, 
        inp_dropout=.0, hidden_dropout=.0, init_lr=.01,
        test_size=.2, val_size=.0, 
        lr_patience=3, es_patience=10, 
        resume_from=None, net='resnet50', load_val_ram=False, 
        load_train_ram=False, no_pos_skip=0., balance_classes=0.,
        pred_img_per_batch=1, pred_roi_per_img=32,
        exam_tsv='./metadata/exams_metadata.tsv',
        img_tsv='./metadata/images_crosswalk.tsv',
        best_model='./modelState/dm_candidROI_best_model.h5',
        final_model="NOSAVE",
        pred_trainval=False, pred_out="dl_pred_out.pkl"):
    '''Run ResNet training on candidate ROIs from mammograms
    Args:
        norm_fit_size ([int]): the number of patients used to calculate 
                feature-wise mean and std.
    '''

    # Read some env variables.
    random_seed = int(os.getenv('RANDOM_SEED', 12345))
    # Use of multiple CPU cores is not working!
    # When nb_worker>1 and pickle_safe=True, this error is encountered:
    # "failed to enqueue async memcpy from host to device: CUDA_ERROR_NOT_INITIALIZED"
    # To avoid the error, only this combination worked: 
    # nb_worker=1 and pickle_safe=False.
    nb_worker = int(os.getenv('NUM_CPU_CORES', 4))
    gpu_count = int(os.getenv('NUM_GPU_DEVICES', 1))
    
    # Setup training and validation data.
    # Load image or exam lists and split them into train and val sets.
    meta_man = DMMetaManager(exam_tsv=exam_tsv, 
                             img_tsv=img_tsv, 
                             img_folder=img_folder, 
                             img_extension=img_extension)
    # Split data based on subjects.
    subj_list, subj_labs = meta_man.get_subj_labs()
    subj_train, subj_test, slab_train, slab_test = train_test_split(
        subj_list, subj_labs, test_size=test_size, random_state=random_seed, 
        stratify=subj_labs)
    if val_size > 0:  # train/val split.
        subj_train, subj_val, slab_train, slab_val = train_test_split(
            subj_train, slab_train, test_size=val_size, 
            random_state=random_seed, stratify=slab_train)
    else:  # use test as val. make a copy of the test list.
        subj_val = list(subj_test)
        slab_val = list(slab_test)
    # import pdb; pdb.set_trace()
    # Subset subject lists to desired ratio.
    if neg_vs_pos_ratio is not None:
        subj_train, slab_train = DMMetaManager.subset_subj_list(
            subj_train, slab_train, neg_vs_pos_ratio, random_seed)
        subj_val, slab_val = DMMetaManager.subset_subj_list(
            subj_val, slab_val, neg_vs_pos_ratio, random_seed)
    print "After sampling, Nb of subjects for train=%d, val=%d, test=%d" \
            % (len(subj_train), len(subj_val), len(subj_test))
    # Get image and label lists.
    img_train, lab_train = meta_man.get_flatten_img_list(subj_train)
    img_val, lab_val = meta_man.get_flatten_img_list(subj_val)

    # Create image generators for train, fit and val.
    imgen_trainval = DMImageDataGenerator()
    if data_augmentation:
        imgen_trainval.horizontal_flip=True 
        imgen_trainval.vertical_flip=True
        imgen_trainval.rotation_range = 45.
        imgen_trainval.shear_range = np.pi/8.
        # imgen_trainval.width_shift_range = .05
        # imgen_trainval.height_shift_range = .05
        # imgen_trainval.zoom_range = [.95, 1.05]

    if do_featurewise_norm:
        imgen_trainval.featurewise_center = True
        imgen_trainval.featurewise_std_normalization = True
        # Fit feature-wise mean and std.
        img_fit,_ = meta_man.get_flatten_img_list(
            subj_train[:norm_fit_size])  # fit on a subset.
        print ">>> Fit image generator <<<"; sys.stdout.flush()
        fit_generator = imgen_trainval.flow_from_candid_roi(
            img_fit,
            target_height=img_height, target_scale=img_scale,
            class_mode=None, validation_mode=True, 
            img_per_batch=len(img_fit), roi_per_img=roi_per_img, 
            roi_size=roi_size,
            low_int_threshold=low_int_threshold, blob_min_area=blob_min_area, 
            blob_min_int=blob_min_int, blob_max_int=blob_max_int, 
            blob_th_step=blob_th_step,
            roi_clf=None, return_sample_weight=False, seed=random_seed)
        imgen_trainval.fit(fit_generator.next())
        print "Estimates from %d images: mean=%.1f, std=%.1f." % \
            (len(img_fit), imgen_trainval.mean, imgen_trainval.std)
        sys.stdout.flush()
    else:
        imgen_trainval.samplewise_center = True
        imgen_trainval.samplewise_std_normalization = True

    # Load ROI classifier.
    if roi_state is not None:
        roi_clf = load_model(
            roi_state, 
            custom_objects={
                'sensitivity': DMMetrics.sensitivity, 
                'specificity': DMMetrics.specificity
            }
        )
        graph = tf.get_default_graph()
    else:
        roi_clf = None
        graph = None

    # Set some DL training related parameters.
    if one_patch_mode:
        class_mode = 'binary'
        loss = 'binary_crossentropy'
        metrics = [DMMetrics.sensitivity, DMMetrics.specificity]
    else:
        class_mode = 'categorical'
        loss = 'categorical_crossentropy'
        metrics = ['accuracy', 'precision', 'recall']
    if load_train_ram:
        validation_mode = True
        return_raw_img = True
    else:
        validation_mode = False
        return_raw_img = False

    # Create train and val generators.
    print ">>> Train image generator <<<"; sys.stdout.flush()
    train_generator = imgen_trainval.flow_from_candid_roi(
        img_train, lab_train, 
        target_height=img_height, target_scale=img_scale,
        class_mode=class_mode, validation_mode=validation_mode, 
        img_per_batch=img_per_batch, roi_per_img=roi_per_img, 
        roi_size=roi_size, one_patch_mode=one_patch_mode,
        low_int_threshold=low_int_threshold, blob_min_area=blob_min_area, 
        blob_min_int=blob_min_int, blob_max_int=blob_max_int, 
        blob_th_step=blob_th_step,
        tf_graph=graph, roi_clf=roi_clf, clf_bs=clf_bs, cutpoint=cutpoint,
        amp_factor=amp_factor, return_sample_weight=return_sample_weight,
        auto_batch_balance=auto_batch_balance,
        all_neg_skip=all_neg_skip, shuffle=True, seed=random_seed,
        return_raw_img=return_raw_img)

    print ">>> Validation image generator <<<"; sys.stdout.flush()
    val_generator = imgen_trainval.flow_from_candid_roi(
        img_val, lab_val, 
        target_height=img_height, target_scale=img_scale,
        class_mode=class_mode, validation_mode=True, 
        img_per_batch=img_per_batch, roi_per_img=roi_per_img, 
        roi_size=roi_size, one_patch_mode=one_patch_mode,
        low_int_threshold=low_int_threshold, blob_min_area=blob_min_area, 
        blob_min_int=blob_min_int, blob_max_int=blob_max_int, 
        blob_th_step=blob_th_step,
        tf_graph=graph, roi_clf=roi_clf, clf_bs=clf_bs, cutpoint=cutpoint,
        amp_factor=amp_factor, return_sample_weight=False, 
        auto_batch_balance=False,
        seed=random_seed)

    # Load train and validation set into RAM.
    if one_patch_mode:
        nb_train_samples = len(img_train)
        nb_val_samples = len(img_val)
    else:
        nb_train_samples = len(img_train)*roi_per_img
        nb_val_samples = len(img_val)*roi_per_img
    if load_val_ram:
        print "Loading validation data into RAM.",
        sys.stdout.flush()
        validation_set = load_dat_ram(val_generator, nb_val_samples)
        print "Done."; sys.stdout.flush()
        sparse_y = to_sparse(validation_set[1])
        for uy in np.unique(sparse_y):
            print "Nb of samples for class:%d = %d" % \
                    (uy, (sparse_y==uy).sum())
        sys.stdout.flush()
    if load_train_ram:
        print "Loading train data into RAM.",
        sys.stdout.flush()
        train_set = load_dat_ram(train_generator, nb_train_samples)
        print "Done."; sys.stdout.flush()
        sparse_y = to_sparse(train_set[1])
        for uy in np.unique(sparse_y):
            print "Nb of samples for class:%d = %d" % \
                    (uy, (sparse_y==uy).sum())
        sys.stdout.flush()
        train_generator = imgen_trainval.flow(
            train_set[0], train_set[1], batch_size=clf_bs, 
            auto_batch_balance=auto_batch_balance, no_pos_skip=no_pos_skip,
            balance_classes=balance_classes, shuffle=True, seed=random_seed)

    # Load or create model.
    if resume_from is not None:
        model = load_model(
            resume_from,
            custom_objects={
                'sensitivity': DMMetrics.sensitivity, 
                'specificity': DMMetrics.specificity
            }
        )
    else:
        builder = ResNetBuilder
        if net == 'resnet18':
            model = builder.build_resnet_18(
                (1, roi_size[0], roi_size[1]), 3, nb_init_filter, init_filter_size, 
                init_conv_stride, pool_size, pool_stride, weight_decay, alpha, l1_ratio, 
                inp_dropout, hidden_dropout)
        elif net == 'resnet34':
            model = builder.build_resnet_34(
                (1, roi_size[0], roi_size[1]), 3, nb_init_filter, init_filter_size, 
                init_conv_stride, pool_size, pool_stride, weight_decay, alpha, l1_ratio, 
                inp_dropout, hidden_dropout)
        elif net == 'resnet50':
            model = builder.build_resnet_50(
                (1, roi_size[0], roi_size[1]), 3, nb_init_filter, init_filter_size, 
                init_conv_stride, pool_size, pool_stride, weight_decay, alpha, l1_ratio, 
                inp_dropout, hidden_dropout)
        elif net == 'resnet101':
            model = builder.build_resnet_101(
                (1, roi_size[0], roi_size[1]), 3, nb_init_filter, init_filter_size, 
                init_conv_stride, pool_size, pool_stride, weight_decay, alpha, l1_ratio, 
                inp_dropout, hidden_dropout)
        elif net == 'resnet152':
            model = builder.build_resnet_152(
                (1, roi_size[0], roi_size[1]), 3, nb_init_filter, init_filter_size, 
                init_conv_stride, pool_size, pool_stride, weight_decay, alpha, l1_ratio, 
                inp_dropout, hidden_dropout)
    
    if gpu_count > 1:
        model = make_parallel(model, gpu_count)

    # Model training.
    sgd = SGD(lr=init_lr, momentum=0.9, decay=0.0, nesterov=True)
    model.compile(optimizer=sgd, loss=loss, metrics=metrics)
    reduce_lr = ReduceLROnPlateau(monitor='val_loss', factor=0.5, 
                                  patience=lr_patience, verbose=1)
    early_stopping = EarlyStopping(monitor='val_loss', patience=es_patience, 
                                   verbose=1)
    if load_val_ram:
        auc_checkpointer = DMAucModelCheckpoint(
            best_model, validation_set, batch_size=clf_bs)
    else:
        auc_checkpointer = DMAucModelCheckpoint(
            best_model, val_generator, nb_test_samples=nb_val_samples)
    hist = model.fit_generator(
        train_generator, 
        samples_per_epoch=patches_per_epoch, 
        nb_epoch=nb_epoch,
        validation_data=validation_set if load_val_ram else val_generator, 
        nb_val_samples=nb_val_samples, 
        callbacks=[reduce_lr, early_stopping, auc_checkpointer],
        # nb_worker=1, pickle_safe=False,
        nb_worker=nb_worker if load_train_ram else 1,
        pickle_safe=True if load_train_ram else False,
        verbose=2)

    if final_model != "NOSAVE":
        print "Saving final model to:", final_model; sys.stdout.flush()
        model.save(final_model)
    
    # Training report.
    min_loss_locs, = np.where(hist.history['val_loss'] == min(hist.history['val_loss']))
    best_val_loss = hist.history['val_loss'][min_loss_locs[0]]
    if one_patch_mode:
        best_val_sensitivity = hist.history['val_sensitivity'][min_loss_locs[0]]
        best_val_specificity = hist.history['val_specificity'][min_loss_locs[0]]
    else:
        best_val_precision = hist.history['val_precision'][min_loss_locs[0]]
        best_val_recall = hist.history['val_recall'][min_loss_locs[0]]
        best_val_accuracy = hist.history['val_acc'][min_loss_locs[0]]
    print "\n==== Training summary ===="
    print "Minimum val loss achieved at epoch:", min_loss_locs[0] + 1
    print "Best val loss:", best_val_loss
    if one_patch_mode:
        print "Best val sensitivity:", best_val_sensitivity
        print "Best val specificity:", best_val_specificity
    else:
        print "Best val precision:", best_val_precision
        print "Best val recall:", best_val_recall
        print "Best val accuracy:", best_val_accuracy

    # Make predictions on train, val, test exam lists.
    if best_model != 'NOSAVE':
        print "\n==== Making predictions ===="
        print "Load best model for prediction:", best_model
        sys.stdout.flush()
        pred_model = load_model(best_model)
        if gpu_count > 1:
            pred_model = make_parallel(pred_model, gpu_count)
        
        if pred_trainval:
            print "Load exam lists for train, val sets"; sys.stdout.flush()
            exam_train = meta_man.get_flatten_exam_list(
                subj_train, flatten_img_list=True)
            print "Train exam list length=", len(exam_train); sys.stdout.flush()
            exam_val = meta_man.get_flatten_exam_list(
                subj_val, flatten_img_list=True)
            print "Val exam list length=", len(exam_val); sys.stdout.flush()
        print "Load exam list for test set"; sys.stdout.flush()
        exam_test = meta_man.get_flatten_exam_list(
            subj_test, flatten_img_list=True)
        print "Test exam list length=", len(exam_test); sys.stdout.flush()
        
        if do_featurewise_norm:
            imgen_pred = DMImageDataGenerator()
            imgen_pred.featurewise_center = True
            imgen_pred.featurewise_std_normalization = True
            imgen_pred.mean = imgen_trainval.mean
            imgen_pred.std = imgen_trainval.std
        else:
            imgen_pred.samplewise_center = True
            imgen_pred.samplewise_std_normalization = True
        
        if pred_trainval:
            print "Make predictions on train exam list"; sys.stdout.flush()
            meta_prob_train = get_exam_pred(
                exam_train, pred_roi_per_img, imgen_pred, 
                target_height=img_height, target_scale=img_scale,
                img_per_batch=pred_img_per_batch, roi_size=roi_size,
                low_int_threshold=low_int_threshold, blob_min_area=blob_min_area, 
                blob_min_int=blob_min_int, blob_max_int=blob_max_int, 
                blob_th_step=blob_th_step, seed=random_seed, 
                dl_model=pred_model)
            print "Train prediction list length=", len(meta_prob_train)
            
            print "Make predictions on val exam list"; sys.stdout.flush()
            meta_prob_val = get_exam_pred(
                exam_val, pred_roi_per_img, imgen_pred, 
                target_height=img_height, target_scale=img_scale,
                img_per_batch=pred_img_per_batch, roi_size=roi_size,
                low_int_threshold=low_int_threshold, blob_min_area=blob_min_area, 
                blob_min_int=blob_min_int, blob_max_int=blob_max_int, 
                blob_th_step=blob_th_step, seed=random_seed, 
                dl_model=pred_model)
            print "Val prediction list length=", len(meta_prob_val)
        
        print "Make predictions on test exam list"; sys.stdout.flush()
        meta_prob_test = get_exam_pred(
            exam_test, pred_roi_per_img, imgen_pred, 
            target_height=img_height, target_scale=img_scale,
            img_per_batch=pred_img_per_batch, roi_size=roi_size,
            low_int_threshold=low_int_threshold, blob_min_area=blob_min_area, 
            blob_min_int=blob_min_int, blob_max_int=blob_max_int, 
            blob_th_step=blob_th_step, seed=random_seed, 
            dl_model=pred_model)
        print "Test prediction list length=", len(meta_prob_test)
        
        if pred_trainval:
            pickle.dump((meta_prob_train, meta_prob_val, meta_prob_test), 
                        open(pred_out, 'w'))
        else:
            pickle.dump(meta_prob_test, open(pred_out, 'w'))

    return hist
コード例 #3
0
def run(img_folder,
        dl_state,
        best_model,
        img_extension='dcm',
        img_height=1024,
        img_scale=255.,
        equalize_hist=False,
        featurewise_center=False,
        featurewise_mean=91.6,
        neg_vs_pos_ratio=1.,
        val_size=.1,
        test_size=.15,
        net='vgg19',
        batch_size=128,
        train_bs_multiplier=.5,
        patch_size=256,
        stride=8,
        roi_cutoff=.9,
        bkg_cutoff=[.5, 1.],
        sample_bkg=True,
        train_out='./scratch/train',
        val_out='./scratch/val',
        test_out='./scratch/test',
        out_img_ext='png',
        neg_name='benign',
        pos_name='malignant',
        bkg_name='background',
        augmentation=True,
        load_train_ram=False,
        load_val_ram=False,
        top_layer_nb=None,
        nb_epoch=10,
        top_layer_epochs=0,
        all_layer_epochs=0,
        optim='sgd',
        init_lr=.01,
        top_layer_multiplier=.01,
        all_layer_multiplier=.0001,
        es_patience=5,
        lr_patience=2,
        weight_decay2=.01,
        bias_multiplier=.1,
        hidden_dropout2=.0,
        exam_tsv='./metadata/exams_metadata.tsv',
        img_tsv='./metadata/images_crosswalk.tsv',
        out='./modelState/subj_lists.pkl'):
    '''Finetune a trained DL model on a different dataset
    '''
    # Read some env variables.
    random_seed = int(os.getenv('RANDOM_SEED', 12345))
    rng = RandomState(random_seed)  # an rng used across board.
    nb_worker = int(os.getenv('NUM_CPU_CORES', 4))
    gpu_count = int(os.getenv('NUM_GPU_DEVICES', 1))

    # Load and split image and label lists.
    meta_man = DMMetaManager(exam_tsv=exam_tsv,
                             img_tsv=img_tsv,
                             img_folder=img_folder,
                             img_extension=img_extension)
    subj_list, subj_labs = meta_man.get_subj_labs()
    subj_labs = np.array(subj_labs)
    print "Found %d subjests" % (len(subj_list))
    print "cancer patients=%d, normal patients=%d" \
            % ((subj_labs==1).sum(), (subj_labs==0).sum())
    if neg_vs_pos_ratio is not None:
        subj_list, subj_labs = DMMetaManager.subset_subj_list(
            subj_list, subj_labs, neg_vs_pos_ratio, random_seed)
        subj_labs = np.array(subj_labs)
        print "After subsetting, there are %d subjects" % (len(subj_list))
        print "cancer patients=%d, normal patients=%d" \
                % ((subj_labs==1).sum(), (subj_labs==0).sum())
    subj_train, subj_test, labs_train, labs_test = train_test_split(
        subj_list,
        subj_labs,
        test_size=test_size,
        stratify=subj_labs,
        random_state=random_seed)
    subj_train, subj_val, labs_train, labs_val = train_test_split(
        subj_train,
        labs_train,
        test_size=val_size,
        stratify=labs_train,
        random_state=random_seed)

    # Get image lists.
    # >>>> Debug <<<< #
    # subj_train = subj_train[:5]
    # subj_val = subj_val[:5]
    # subj_test = subj_test[:5]
    # >>>> Debug <<<< #
    print "Get flattened image lists"
    img_train, ilab_train = meta_man.get_flatten_img_list(subj_train)
    img_val, ilab_val = meta_man.get_flatten_img_list(subj_val)
    img_test, ilab_test = meta_man.get_flatten_img_list(subj_test)
    ilab_train = np.array(ilab_train)
    ilab_val = np.array(ilab_val)
    ilab_test = np.array(ilab_test)
    print "On train set, positive img=%d, negative img=%d" \
            % ((ilab_train==1).sum(), (ilab_train==0).sum())
    print "On val set, positive img=%d, negative img=%d" \
            % ((ilab_val==1).sum(), (ilab_val==0).sum())
    print "On test set, positive img=%d, negative img=%d" \
            % ((ilab_test==1).sum(), (ilab_test==0).sum())
    sys.stdout.flush()

    # Save the subj lists.
    print "Saving subject lists to external files.",
    sys.stdout.flush()
    pickle.dump((subj_train, subj_val, subj_test), open(out, 'w'))
    print "Done."

    # Load DL model, preprocess function.
    print "Load patch classifier:", dl_state
    sys.stdout.flush()
    dl_model, preprocess_input, top_layer_nb = get_dl_model(
        net,
        use_pretrained=True,
        resume_from=dl_state,
        top_layer_nb=top_layer_nb)
    if featurewise_center:
        preprocess_input = None
    if gpu_count > 1:
        print "Make the model parallel on %d GPUs" % (gpu_count)
        sys.stdout.flush()
        dl_model, org_model = make_parallel(dl_model, gpu_count)
        parallelized = True
    else:
        org_model = dl_model
        parallelized = False

    # Sweep the whole images and classify patches.
    print "Score image patches and write them to:", train_out
    sys.stdout.flush()
    nb_roi_train, nb_bkg_train = score_write_patches(
        img_train,
        ilab_train,
        img_height,
        img_scale,
        patch_size,
        stride,
        dl_model,
        batch_size,
        neg_out=os.path.join(train_out, neg_name),
        pos_out=os.path.join(train_out, pos_name),
        bkg_out=os.path.join(train_out, bkg_name),
        preprocess=preprocess_input,
        equalize_hist=equalize_hist,
        featurewise_center=featurewise_center,
        featurewise_mean=featurewise_mean,
        roi_cutoff=roi_cutoff,
        bkg_cutoff=bkg_cutoff,
        sample_bkg=sample_bkg,
        img_ext=out_img_ext,
        random_seed=random_seed,
        parallelized=parallelized)
    print "Wrote %d ROI and %d bkg patches" % (nb_roi_train, nb_bkg_train)
    ####
    print "Score image patches and write them to:", val_out
    sys.stdout.flush()
    nb_roi_val, nb_bkg_val = score_write_patches(
        img_val,
        ilab_val,
        img_height,
        img_scale,
        patch_size,
        stride,
        dl_model,
        batch_size,
        neg_out=os.path.join(val_out, neg_name),
        pos_out=os.path.join(val_out, pos_name),
        bkg_out=os.path.join(val_out, bkg_name),
        preprocess=preprocess_input,
        equalize_hist=equalize_hist,
        featurewise_center=featurewise_center,
        featurewise_mean=featurewise_mean,
        roi_cutoff=roi_cutoff,
        bkg_cutoff=bkg_cutoff,
        sample_bkg=sample_bkg,
        img_ext=out_img_ext,
        random_seed=random_seed,
        parallelized=parallelized)
    print "Wrote %d ROI and %d bkg patches" % (nb_roi_val, nb_bkg_val)
    ####
    print "Score image patches and write them to:", test_out
    sys.stdout.flush()
    nb_roi_test, nb_bkg_test = score_write_patches(
        img_test,
        ilab_test,
        img_height,
        img_scale,
        patch_size,
        stride,
        dl_model,
        batch_size,
        neg_out=os.path.join(test_out, neg_name),
        pos_out=os.path.join(test_out, pos_name),
        bkg_out=os.path.join(test_out, bkg_name),
        preprocess=preprocess_input,
        equalize_hist=equalize_hist,
        featurewise_center=featurewise_center,
        featurewise_mean=featurewise_mean,
        roi_cutoff=roi_cutoff,
        bkg_cutoff=bkg_cutoff,
        sample_bkg=sample_bkg,
        img_ext=out_img_ext,
        random_seed=random_seed,
        parallelized=parallelized)
    print "Wrote %d ROI and %d bkg patches" % (nb_roi_test, nb_bkg_test)
    sys.stdout.flush()

    # ==== Image generators ==== #
    if featurewise_center:
        train_imgen = DMImageDataGenerator(featurewise_center=True)
        val_imgen = DMImageDataGenerator(featurewise_center=True)
        test_imgen = DMImageDataGenerator(featurewise_center=True)
        train_imgen.mean = featurewise_mean
        val_imgen.mean = featurewise_mean
        test_imgen.mean = featurewise_mean
    else:
        train_imgen = DMImageDataGenerator()
        val_imgen = DMImageDataGenerator()
        test_imgen = DMImageDataGenerator()
    if augmentation:
        train_imgen.horizontal_flip = True
        train_imgen.vertical_flip = True
        train_imgen.rotation_range = 45.
        train_imgen.shear_range = np.pi / 8.

    # ==== Train & val set ==== #
    # Note: the images are histogram equalized before they were written to
    # external folders.
    train_bs = int(batch_size * train_bs_multiplier)
    if load_train_ram:
        raw_imgen = DMImageDataGenerator()
        print "Create generator for raw train set"
        raw_generator = raw_imgen.flow_from_directory(
            train_out,
            target_size=(patch_size, patch_size),
            target_scale=img_scale,
            equalize_hist=False,
            dup_3_channels=True,
            classes=[bkg_name, pos_name, neg_name],
            class_mode='categorical',
            batch_size=train_bs,
            shuffle=False)
        print "Loading raw train set into RAM.",
        sys.stdout.flush()
        raw_set = load_dat_ram(raw_generator, raw_generator.nb_sample)
        print "Done."
        sys.stdout.flush()
        print "Create generator for train set"
        train_generator = train_imgen.flow(raw_set[0],
                                           raw_set[1],
                                           batch_size=train_bs,
                                           auto_batch_balance=True,
                                           preprocess=preprocess_input,
                                           shuffle=True,
                                           seed=random_seed)
    else:
        print "Create generator for train set"
        train_generator = train_imgen.flow_from_directory(
            train_out,
            target_size=(patch_size, patch_size),
            target_scale=img_scale,
            equalize_hist=False,
            dup_3_channels=True,
            classes=[bkg_name, pos_name, neg_name],
            class_mode='categorical',
            auto_batch_balance=True,
            batch_size=train_bs,
            preprocess=preprocess_input,
            shuffle=True,
            seed=random_seed)

    print "Create generator for val set"
    sys.stdout.flush()
    validation_set = val_imgen.flow_from_directory(
        val_out,
        target_size=(patch_size, patch_size),
        target_scale=img_scale,
        equalize_hist=False,
        dup_3_channels=True,
        classes=[bkg_name, pos_name, neg_name],
        class_mode='categorical',
        batch_size=batch_size,
        preprocess=preprocess_input,
        shuffle=False)
    val_samples = validation_set.nb_sample
    if parallelized and val_samples % batch_size != 0:
        val_samples -= val_samples % batch_size
    print "Validation samples =", val_samples
    sys.stdout.flush()
    if load_val_ram:
        print "Loading validation set into RAM.",
        sys.stdout.flush()
        validation_set = load_dat_ram(validation_set, val_samples)
        print "Done."
        print "Loaded %d val samples" % (len(validation_set[0]))
        sys.stdout.flush()

    # ==== Model finetuning ==== #
    train_batches = int(train_generator.nb_sample / train_bs) + 1
    samples_per_epoch = train_bs * train_batches
    # import pdb; pdb.set_trace()
    dl_model, loss_hist, acc_hist = do_3stage_training(
        dl_model,
        org_model,
        train_generator,
        validation_set,
        val_samples,
        best_model,
        samples_per_epoch,
        top_layer_nb,
        net,
        nb_epoch=nb_epoch,
        top_layer_epochs=top_layer_epochs,
        all_layer_epochs=all_layer_epochs,
        use_pretrained=True,
        optim=optim,
        init_lr=init_lr,
        top_layer_multiplier=top_layer_multiplier,
        all_layer_multiplier=all_layer_multiplier,
        es_patience=es_patience,
        lr_patience=lr_patience,
        auto_batch_balance=True,
        nb_worker=nb_worker,
        weight_decay2=weight_decay2,
        bias_multiplier=bias_multiplier,
        hidden_dropout2=hidden_dropout2)

    # Training report.
    min_loss_locs, = np.where(loss_hist == min(loss_hist))
    best_val_loss = loss_hist[min_loss_locs[0]]
    best_val_accuracy = acc_hist[min_loss_locs[0]]
    print "\n==== Training summary ===="
    print "Minimum val loss achieved at epoch:", min_loss_locs[0] + 1
    print "Best val loss:", best_val_loss
    print "Best val accuracy:", best_val_accuracy

    # ==== Predict on test set ==== #
    print "\n==== Predicting on test set ===="
    print "Create generator for test set"
    test_generator = test_imgen.flow_from_directory(
        test_out,
        target_size=(patch_size, patch_size),
        target_scale=img_scale,
        equalize_hist=False,
        dup_3_channels=True,
        classes=[bkg_name, pos_name, neg_name],
        class_mode='categorical',
        batch_size=batch_size,
        preprocess=preprocess_input,
        shuffle=False)
    test_samples = test_generator.nb_sample
    if parallelized and test_samples % batch_size != 0:
        test_samples -= test_samples % batch_size
    print "Test samples =", test_samples
    print "Load saved best model:", best_model + '.',
    sys.stdout.flush()
    org_model.load_weights(best_model)
    print "Done."
    test_res = dl_model.evaluate_generator(
        test_generator,
        test_samples,
        nb_worker=nb_worker,
        pickle_safe=True if nb_worker > 1 else False)
    print "Evaluation result on test set:", test_res
コード例 #4
0
def run(img_folder, dl_state, img_extension='dcm', 
        img_height=1024, img_scale=4095, val_size=.2, neg_vs_pos_ratio=10., 
        do_featurewise_norm=True, featurewise_mean=873.6, featurewise_std=739.3,
        img_per_batch=2, roi_per_img=32, roi_size=(256, 256), 
        low_int_threshold=.05, blob_min_area=3, 
        blob_min_int=.5, blob_max_int=.85, blob_th_step=10,
        exam_tsv='./metadata/exams_metadata.tsv',
        img_tsv='./metadata/images_crosswalk.tsv',
        train_out='./modelState/meta_prob_train.pkl',
        test_out='./modelState/meta_prob_test.pkl'):
    '''Calculate bag of deep visual words count matrix for all breasts
    '''

    # Read some env variables.
    random_seed = int(os.getenv('RANDOM_SEED', 12345))
    rng = RandomState(random_seed)  # an rng used across board.
    gpu_count = int(os.getenv('NUM_GPU_DEVICES', 1))

    # Load and split image and label lists.
    meta_man = DMMetaManager(exam_tsv=exam_tsv, 
                             img_tsv=img_tsv, 
                             img_folder=img_folder, 
                             img_extension=img_extension)
    subj_list, subj_labs = meta_man.get_subj_labs()
    subj_train, subj_test, labs_train, labs_test = train_test_split(
        subj_list, subj_labs, test_size=val_size, stratify=subj_labs, 
        random_state=random_seed)
    if neg_vs_pos_ratio is not None:
        def subset_subj(subj, labs):
            subj = np.array(subj)
            labs = np.array(labs)
            pos_idx = np.where(labs==1)[0]
            neg_idx = np.where(labs==0)[0]
            nb_neg_desired = int(len(pos_idx)*neg_vs_pos_ratio)
            if nb_neg_desired >= len(neg_idx):
                return subj.tolist()
            else:
                neg_chosen = rng.choice(neg_idx, nb_neg_desired, replace=False)
                subset_idx = np.concatenate([pos_idx, neg_chosen])
                return subj[subset_idx].tolist()

        subj_train = subset_subj(subj_train, labs_train)
        subj_test = subset_subj(subj_test, labs_test)

    # Create image generator for ROIs for representation extraction.
    print "Create an image generator for ROIs"; sys.stdout.flush()
    if do_featurewise_norm:
        imgen = DMImageDataGenerator(
            featurewise_center=True, 
            featurewise_std_normalization=True)
        imgen.mean = featurewise_mean
        imgen.std = featurewise_std
    else:
        imgen = DMImageDataGenerator(
            samplewise_center=True, 
            samplewise_std_normalization=True)

    # Load DL model.
    print "Load DL classification model:", dl_state; sys.stdout.flush()
    dl_model = load_model(
        dl_state, 
        custom_objects={
            'sensitivity': dmm.sensitivity, 
            'specificity': dmm.specificity
        }
    )
    if gpu_count > 1:
        print "Make the model parallel on %d GPUs" % (gpu_count)
        sys.stdout.flush()
        dl_model = make_parallel(dl_model, gpu_count)

    # Read exam lists.
    exam_train = meta_man.get_flatten_exam_list(
        subj_train, flatten_img_list=True)
    exam_test = meta_man.get_flatten_exam_list(
        subj_test, flatten_img_list=True)
    exam_labs_train = np.array(meta_man.exam_labs(exam_train))
    exam_labs_test = np.array(meta_man.exam_labs(exam_test))
    nb_pos_exams_train = (exam_labs_train==1).sum()
    nb_neg_exams_train = (exam_labs_train==0).sum()
    nb_pos_exams_test = (exam_labs_test==1).sum()
    nb_neg_exams_test = (exam_labs_test==0).sum()
    print "Train set - Nb of pos exams: %d, Nb of neg exams: %d" % \
            (nb_pos_exams_train, nb_neg_exams_train)
    print "Test set - Nb of pos exams: %d, Nb of neg exams: %d" % \
            (nb_pos_exams_test, nb_neg_exams_test)

    # Make predictions for exam lists.
    print "Predicting for train exam list"; sys.stdout.flush()
    meta_prob_train = get_exam_pred(
        exam_train, roi_per_img, imgen, 
        target_height=img_height, target_scale=img_scale,
        img_per_batch=img_per_batch, roi_size=roi_size,
        low_int_threshold=low_int_threshold, blob_min_area=blob_min_area, 
        blob_min_int=blob_min_int, blob_max_int=blob_max_int, 
        blob_th_step=blob_th_step, seed=random_seed, 
        dl_model=dl_model)
    print "Length of train prediction list:", len(meta_prob_train)
    sys.stdout.flush()

    print "Predicting for test exam list"; sys.stdout.flush()
    meta_prob_test = get_exam_pred(
        exam_test, roi_per_img, imgen, 
        target_height=img_height, target_scale=img_scale,
        img_per_batch=img_per_batch, roi_size=roi_size,
        low_int_threshold=low_int_threshold, blob_min_area=blob_min_area, 
        blob_min_int=blob_min_int, blob_max_int=blob_max_int, 
        blob_th_step=blob_th_step, seed=random_seed, 
        dl_model=dl_model)
    print "Length of test prediction list:", len(meta_prob_test)
    sys.stdout.flush()

    pickle.dump(meta_prob_train, open(train_out, 'w'))
    pickle.dump(meta_prob_test, open(test_out, 'w'))
    print "Done."
コード例 #5
0
def run(img_folder,
        dl_state,
        img_extension='dcm',
        img_height=1024,
        img_scale=255.,
        equalize_hist=False,
        featurewise_center=False,
        featurewise_mean=91.6,
        neg_vs_pos_ratio=1.,
        net='vgg19',
        batch_size=128,
        patch_size=256,
        stride=8,
        exam_tsv='./metadata/exams_metadata.tsv',
        img_tsv='./metadata/images_crosswalk.tsv',
        out='./modelState/prob_heatmap.pkl',
        predicted_subj_file=None,
        add_subjs=500):
    '''Sweep mammograms with trained DL model to create prob heatmaps
    '''
    # Read some env variables.
    random_seed = int(os.getenv('RANDOM_SEED', 12345))
    rng = RandomState(random_seed)  # an rng used across board.
    gpu_count = int(os.getenv('NUM_GPU_DEVICES', 1))

    # Load and split image and label lists.
    meta_man = DMMetaManager(exam_tsv=exam_tsv,
                             img_tsv=img_tsv,
                             img_folder=img_folder,
                             img_extension=img_extension)
    subj_list, subj_labs = meta_man.get_subj_labs()
    subj_labs = np.array(subj_labs)
    print "Found %d subjests" % (len(subj_list))
    print "cancer patients=%d, normal patients=%d" \
            % ((subj_labs==1).sum(), (subj_labs==0).sum())
    if predicted_subj_file is not None:
        predicted_subjs = np.load(predicted_subj_file)
        subj_list = np.setdiff1d(subj_list, predicted_subjs)
        subj_list = subj_list[:add_subjs]
        print "Will predict additional %d subjects" % (len(subj_list))
    elif neg_vs_pos_ratio is not None:
        subj_list, subj_labs = DMMetaManager.subset_subj_list(
            subj_list, subj_labs, neg_vs_pos_ratio, random_seed)
        subj_labs = np.array(subj_labs)
        print "After subsetting, there are %d subjects" % (len(subj_list))
        print "cancer patients=%d, normal patients=%d" \
                % ((subj_labs==1).sum(), (subj_labs==0).sum())

    # Get exam lists.
    # >>>> Debug <<<< #
    # subj_list = subj_list[:2]
    # >>>> Debug <<<< #
    print "Get flattened exam list"
    exam_list = meta_man.get_flatten_exam_list(subj_list, cc_mlo_only=True)
    exam_labs = meta_man.exam_labs(exam_list)
    exam_labs = np.array(exam_labs)
    print "positive exams=%d, negative exams=%d" \
            % ((exam_labs==1).sum(), (exam_labs==0).sum())
    sys.stdout.flush()

    # Load DL model.
    print "Load patch classifier:", dl_state
    sys.stdout.flush()
    dl_model = load_model(dl_state,
                          custom_objects={
                              'sensitivity': dmm.sensitivity,
                              'specificity': dmm.specificity
                          })

    if gpu_count > 1:
        print "Make the model parallel on %d GPUs" % (gpu_count)
        sys.stdout.flush()
        dl_model, _ = make_parallel(dl_model, gpu_count)
        parallelized = True
    else:
        parallelized = False

    # Load preprocess function.
    if featurewise_center:
        preprocess_input = None
    else:
        print "Load preprocess function for net:", net
        if net == 'resnet50':
            from keras.applications.resnet50 import preprocess_input
        elif net == 'vgg16':
            from keras.applications.vgg16 import preprocess_input
        elif net == 'vgg19':
            from keras.applications.vgg19 import preprocess_input
        elif net == 'xception':
            from keras.applications.xception import preprocess_input
        elif net == 'inception':
            from keras.applications.inception_v3 import preprocess_input
        else:
            raise Exception("Pretrained model is not available: " + net)

    # Sweep the whole images and classify patches.
    print "Generate prob heatmaps for exam list"
    sys.stdout.flush()
    heatmap_dat_list = []
    for i, e in enumerate(exam_list):
        dat = (e[0], e[1], {
            'L': {
                'cancer': e[2]['L']['cancer']
            },
            'R': {
                'cancer': e[2]['R']['cancer']
            }
        })
        dat[2]['L']['CC'] = get_prob_heatmap(
            e[2]['L']['CC'],
            img_height,
            img_scale,
            patch_size,
            stride,
            dl_model,
            batch_size,
            featurewise_center=featurewise_center,
            featurewise_mean=featurewise_mean,
            preprocess=preprocess_input,
            parallelized=parallelized,
            equalize_hist=equalize_hist)
        dat[2]['L']['MLO'] = get_prob_heatmap(
            e[2]['L']['MLO'],
            img_height,
            img_scale,
            patch_size,
            stride,
            dl_model,
            batch_size,
            featurewise_center=featurewise_center,
            featurewise_mean=featurewise_mean,
            preprocess=preprocess_input,
            parallelized=parallelized,
            equalize_hist=equalize_hist)
        dat[2]['R']['CC'] = get_prob_heatmap(
            e[2]['R']['CC'],
            img_height,
            img_scale,
            patch_size,
            stride,
            dl_model,
            batch_size,
            featurewise_center=featurewise_center,
            featurewise_mean=featurewise_mean,
            preprocess=preprocess_input,
            parallelized=parallelized,
            equalize_hist=equalize_hist)
        dat[2]['R']['MLO'] = get_prob_heatmap(
            e[2]['R']['MLO'],
            img_height,
            img_scale,
            patch_size,
            stride,
            dl_model,
            batch_size,
            featurewise_center=featurewise_center,
            featurewise_mean=featurewise_mean,
            preprocess=preprocess_input,
            parallelized=parallelized,
            equalize_hist=equalize_hist)
        heatmap_dat_list.append(dat)
        print "processed %d/%d exams" % (i + 1, len(exam_list))
        sys.stdout.flush()
        ### DEBUG ###
        # if i >= 1:
        #    break
        ### DEBUG ###
    print "Done."

    # Save the result.
    print "Saving result to external files.",
    sys.stdout.flush()
    pickle.dump(heatmap_dat_list, open(out, 'w'))
    print "Done."
コード例 #6
0
def run(img_folder,
        dl_state,
        img_extension='dcm',
        img_height=1024,
        img_scale=4095,
        val_size=.2,
        neg_vs_pos_ratio=10.,
        do_featurewise_norm=True,
        featurewise_mean=873.6,
        featurewise_std=739.3,
        img_per_batch=2,
        roi_per_img=32,
        roi_size=(256, 256),
        low_int_threshold=.05,
        blob_min_area=3,
        blob_min_int=.5,
        blob_max_int=.85,
        blob_th_step=10,
        layer_name=['flatten_1', 'dense_1'],
        layer_index=None,
        roi_state=None,
        roi_clf_bs=32,
        pc_components=.95,
        pc_whiten=True,
        nb_words=[512],
        km_max_iter=100,
        km_bs=1000,
        km_patience=20,
        km_init=10,
        exam_tsv='./metadata/exams_metadata.tsv',
        img_tsv='./metadata/images_crosswalk.tsv',
        pca_km_states='./modelState/dlrepr_pca_km_models.pkl',
        bow_train_out='./modelState/bow_dat_train.pkl',
        bow_test_out='./modelState/bow_dat_test.pkl'):
    '''Calculate bag of deep visual words count matrix for all breasts
    '''

    # Read some env variables.
    random_seed = int(os.getenv('RANDOM_SEED', 12345))
    rng = RandomState(random_seed)  # an rng used across board.

    # Load and split image and label lists.
    meta_man = DMMetaManager(exam_tsv=exam_tsv,
                             img_tsv=img_tsv,
                             img_folder=img_folder,
                             img_extension=img_extension)
    subj_list, subj_labs = meta_man.get_subj_labs()
    subj_train, subj_test, labs_train, labs_test = train_test_split(
        subj_list,
        subj_labs,
        test_size=val_size,
        stratify=subj_labs,
        random_state=random_seed)
    if neg_vs_pos_ratio is not None:

        def subset_subj(subj, labs):
            subj = np.array(subj)
            labs = np.array(labs)
            pos_idx = np.where(labs == 1)[0]
            neg_idx = np.where(labs == 0)[0]
            nb_neg_desired = int(len(pos_idx) * neg_vs_pos_ratio)
            if nb_neg_desired >= len(neg_idx):
                return subj.tolist()
            else:
                neg_chosen = rng.choice(neg_idx, nb_neg_desired, replace=False)
                subset_idx = np.concatenate([pos_idx, neg_chosen])
                return subj[subset_idx].tolist()

        subj_train = subset_subj(subj_train, labs_train)
        subj_test = subset_subj(subj_test, labs_test)

    img_list, lab_list = meta_man.get_flatten_img_list(subj_train)
    lab_list = np.array(lab_list)
    print "Train set - Nb of positive images: %d, Nb of negative images: %d" \
            % ( (lab_list==1).sum(), (lab_list==0).sum())
    sys.stdout.flush()

    # Create image generator for ROIs for representation extraction.
    print "Create an image generator for ROIs"
    sys.stdout.flush()
    if do_featurewise_norm:
        imgen = DMImageDataGenerator(featurewise_center=True,
                                     featurewise_std_normalization=True)
        imgen.mean = featurewise_mean
        imgen.std = featurewise_std
    else:
        imgen = DMImageDataGenerator(samplewise_center=True,
                                     samplewise_std_normalization=True)

    # Load ROI classifier.
    if roi_state is not None:
        print "Load ROI classifier"
        sys.stdout.flush()
        roi_clf = load_model(roi_state,
                             custom_objects={
                                 'sensitivity': dmm.sensitivity,
                                 'specificity': dmm.specificity
                             })
        graph = tf.get_default_graph()
    else:
        roi_clf = None
        graph = None

    # Create ROI generators for pos and neg images separately.
    print "Create ROI generators for pos and neg images"
    sys.stdout.flush()
    roi_generator = imgen.flow_from_candid_roi(
        img_list,
        target_height=img_height,
        target_scale=img_scale,
        class_mode=None,
        validation_mode=True,
        img_per_batch=img_per_batch,
        roi_per_img=roi_per_img,
        roi_size=roi_size,
        low_int_threshold=low_int_threshold,
        blob_min_area=blob_min_area,
        blob_min_int=blob_min_int,
        blob_max_int=blob_max_int,
        blob_th_step=blob_th_step,
        tf_graph=graph,
        roi_clf=roi_clf,
        clf_bs=roi_clf_bs,
        return_sample_weight=False,
        seed=random_seed)

    # Generate image patches and extract their DL representations.
    print "Load DL representation model"
    sys.stdout.flush()
    dlrepr_model = DLRepr(dl_state,
                          custom_objects={
                              'sensitivity': dmm.sensitivity,
                              'specificity': dmm.specificity
                          },
                          layer_name=layer_name,
                          layer_index=layer_index)
    last_output_size = dlrepr_model.get_output_shape()[-1][-1]
    if last_output_size != 3 and last_output_size != 1:
        raise Exception("The last output must be prob outputs (size=3 or 1)")

    nb_tot_samples = len(img_list) * roi_per_img
    print "Extract ROIs from pos and neg images"
    sys.stdout.flush()
    pred = dlrepr_model.predict_generator(roi_generator,
                                          val_samples=nb_tot_samples)
    for i, d in enumerate(pred):
        print "Shape of representation/output data %d:" % (i), d.shape
    sys.stdout.flush()

    # Flatten feature maps, e.g. an 8x8 feature map will become a 64-d vector.
    pred = [d.reshape((-1, d.shape[-1])) for d in pred]
    for i, d in enumerate(pred):
        print "Shape of flattened data %d:" % (i), d.shape
    sys.stdout.flush()

    # Split representations and prob outputs.
    dl_repr = pred[0]
    prob_out = pred[1]
    if prob_out.shape[1] == 3:
        prob_out = prob_out[:, 1]  # pos class.
    prob_out = prob_out.reshape((len(img_list), -1))
    print "Reshape prob output to:", prob_out.shape
    sys.stdout.flush()

    # Use PCA to reduce dimension of the representation data.
    if pc_components is not None:
        print "Start PCA dimension reduction on DL representation"
        sys.stdout.flush()
        pca = PCA(n_components=pc_components, whiten=pc_whiten)
        pca.fit(dl_repr)
        print "Nb of PCA components:", pca.n_components_
        print "Total explained variance ratio: %.4f" % \
                (pca.explained_variance_ratio_.sum())
        dl_repr_pca = pca.transform(dl_repr)
        print "Shape of transformed representation data:", dl_repr_pca.shape
        sys.stdout.flush()
    else:
        pca = None

    # Use K-means to create a codebook for deep visual words.
    print "Start K-means training on DL representation"
    sys.stdout.flush()
    clf_list = []
    clust_list = []
    # Shuffling indices for mini-batches learning.
    perm_idx = rng.permutation(len(dl_repr))
    for n in nb_words:
        print "Train K-means with %d cluster centers" % (n)
        sys.stdout.flush()
        clf = MiniBatchKMeans(n_clusters=n,
                              init='k-means++',
                              max_iter=km_max_iter,
                              batch_size=km_bs,
                              compute_labels=True,
                              random_state=random_seed,
                              tol=0.0,
                              max_no_improvement=km_patience,
                              init_size=None,
                              n_init=km_init,
                              reassignment_ratio=0.01,
                              verbose=0)
        clf.fit(dl_repr[perm_idx])
        clf_list.append(clf)
        clust = np.zeros_like(clf.labels_)
        clust[perm_idx] = clf.labels_
        clust = clust.reshape((len(img_list), -1))
        clust_list.append(clust)

    if pca is not None:
        print "Start K-means training on transformed representation"
        sys.stdout.flush()
        clf_list_pca = []
        clust_list_pca = []
        # Shuffling indices for mini-batches learning.
        perm_idx = rng.permutation(len(dl_repr_pca))
        for n in nb_words:
            print "Train K-means with %d cluster centers" % (n)
            sys.stdout.flush()
            clf = MiniBatchKMeans(n_clusters=n,
                                  init='k-means++',
                                  max_iter=km_max_iter,
                                  batch_size=km_bs,
                                  compute_labels=True,
                                  random_state=random_seed,
                                  tol=0.0,
                                  max_no_improvement=km_patience,
                                  init_size=None,
                                  n_init=km_init,
                                  reassignment_ratio=0.01,
                                  verbose=0)
            clf.fit(dl_repr_pca[perm_idx])
            clf_list_pca.append(clf)
            clust = np.zeros_like(clf.labels_)
            clust[perm_idx] = clf.labels_
            clust = clust.reshape((len(img_list), -1))
            clust_list_pca.append(clust)

    # Read exam lists.
    exam_train = meta_man.get_flatten_exam_list(subj_train,
                                                flatten_img_list=True)
    exam_test = meta_man.get_flatten_exam_list(subj_test,
                                               flatten_img_list=True)
    exam_labs_train = np.array(meta_man.exam_labs(exam_train))
    exam_labs_test = np.array(meta_man.exam_labs(exam_test))
    nb_pos_exams_train = (exam_labs_train == 1).sum()
    nb_neg_exams_train = (exam_labs_train == 0).sum()
    nb_pos_exams_test = (exam_labs_test == 1).sum()
    nb_neg_exams_test = (exam_labs_test == 0).sum()
    print "Train set - Nb of pos exams: %d, Nb of neg exams: %d" % \
            (nb_pos_exams_train, nb_neg_exams_train)
    print "Test set - Nb of pos exams: %d, Nb of neg exams: %d" % \
            (nb_pos_exams_test, nb_neg_exams_test)

    # Do BoW counts for each breast.
    print "BoW counting for train exam list"
    sys.stdout.flush()
    bow_dat_train = get_exam_bow_dat(exam_train,
                                     nb_words,
                                     roi_per_img,
                                     img_list=img_list,
                                     prob_out=prob_out,
                                     clust_list=clust_list)
    for i, d in enumerate(bow_dat_train[1]):
        print "Shape of train BoW matrix %d:" % (i), d.shape
    sys.stdout.flush()

    print "BoW counting for test exam list"
    sys.stdout.flush()
    bow_dat_test = get_exam_bow_dat(exam_test,
                                    nb_words,
                                    roi_per_img,
                                    imgen=imgen,
                                    clf_list=clf_list,
                                    transformer=None,
                                    target_height=img_height,
                                    target_scale=img_scale,
                                    img_per_batch=img_per_batch,
                                    roi_size=roi_size,
                                    low_int_threshold=low_int_threshold,
                                    blob_min_area=blob_min_area,
                                    blob_min_int=blob_min_int,
                                    blob_max_int=blob_max_int,
                                    blob_th_step=blob_th_step,
                                    seed=random_seed,
                                    dlrepr_model=dlrepr_model)
    for i, d in enumerate(bow_dat_test[1]):
        print "Shape of test BoW matrix %d:" % (i), d.shape
    sys.stdout.flush()

    if pca is not None:
        print "== Do same BoW counting on PCA transformed data =="
        print "BoW counting for train exam list"
        sys.stdout.flush()
        bow_dat_train_pca = get_exam_bow_dat(exam_train,
                                             nb_words,
                                             roi_per_img,
                                             img_list=img_list,
                                             prob_out=prob_out,
                                             clust_list=clust_list_pca)
        for i, d in enumerate(bow_dat_train_pca[1]):
            print "Shape of train BoW matrix %d:" % (i), d.shape
        sys.stdout.flush()

        print "BoW counting for test exam list"
        sys.stdout.flush()
        bow_dat_test_pca = get_exam_bow_dat(
            exam_test,
            nb_words,
            roi_per_img,
            imgen=imgen,
            clf_list=clf_list_pca,
            transformer=pca,
            target_height=img_height,
            target_scale=img_scale,
            img_per_batch=img_per_batch,
            roi_size=roi_size,
            low_int_threshold=low_int_threshold,
            blob_min_area=blob_min_area,
            blob_min_int=blob_min_int,
            blob_max_int=blob_max_int,
            blob_th_step=blob_th_step,
            seed=random_seed,
            dlrepr_model=dlrepr_model)
        for i, d in enumerate(bow_dat_test_pca[1]):
            print "Shape of test BoW matrix %d:" % (i), d.shape
        sys.stdout.flush()

    # Save K-means model and BoW count data.
    if pca is None:
        pickle.dump(clf_list, open(pca_km_states, 'w'))
        pickle.dump(bow_dat_train, open(bow_train_out, 'w'))
        pickle.dump(bow_dat_test, open(bow_test_out, 'w'))
    else:
        pickle.dump((pca, clf_list), open(pca_km_states, 'w'))
        pickle.dump((bow_dat_train, bow_dat_train_pca),
                    open(bow_train_out, 'w'))
        pickle.dump((bow_dat_test, bow_dat_test_pca), open(bow_test_out, 'w'))

    print "Done."