11 files changed, 820 insertions, 0 deletions
diff --git a/cv/holiday_similarity/__init__.py b/cv/holiday_similarity/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/cv/holiday_similarity/__init__.py
diff --git a/cv/holiday_similarity/data_utils.py b/cv/holiday_similarity/data_utils.py
new file mode 100644
index 0000000..1601706
--- /dev/null
+++ b/cv/holiday_similarity/data_utils.py
@@ -0,0 +1,183 @@
+import matplotlib.pyplot as plt
+import numpy as np
+import os
+from PIL import Image
+import itertools
+from random import shuffle
+from keras.utils import np_utils
+from keras.applications import imagenet_utils
+import itertools
+import os
+from random import shuffle
+
+import matplotlib.pyplot as plt
+import numpy as np
+from PIL import Image
+from keras.applications import imagenet_utils
+from keras.utils import np_utils
+
+IMAGE_DIR = '/Users/chunhuizhang/workspaces/00_datasets/images/INRIA Holidays dataset /jpg'
+# IMAGE_DIR = os.path.join(DATA_DIR, "holiday-photos")
+
+image_cache = {}
+
+
+def pair_generator(triples, image_cache, datagens, batch_size=32):
+    while True:
+        # shuffle once per batch
+        indices = np.random.permutation(np.arange(len(triples)))
+        num_batches = len(triples) // batch_size
+        for bid in range(num_batches):
+            batch_indices = indices[bid * batch_size: (bid + 1) * batch_size]
+            batch = [triples[i] for i in batch_indices]
+            X1 = np.zeros((batch_size, 224, 224, 3))
+            X2 = np.zeros((batch_size, 224, 224, 3))
+            Y = np.zeros((batch_size, 2))
+            for i, (image_filename_l, image_filename_r, label) in enumerate(batch):
+                if datagens is None or len(datagens) == 0:
+                    X1[i] = image_cache[image_filename_l]
+                    X2[i] = image_cache[image_filename_r]
+                else:
+                    X1[i] = datagens[0].random_transform(image_cache[image_filename_l])
+                    X2[i] = datagens[1].random_transform(image_cache[image_filename_r])
+                Y[i] = [1, 0] if label == 0 else [0, 1]
+            yield [X1, X2], Y
+
+
+def image_batch_generator(image_names, batch_size):
+    num_batches = len(image_names) // batch_size
+    for i in range(num_batches):
+        batch = image_names[i * batch_size: (i + 1) * batch_size]
+        yield batch
+    batch = image_names[(i + 1) * batch_size:]
+    yield batch
+
+
+def show_img(sid, img_file, img_title):
+    plt.subplot(sid)
+    plt.title(img_title)
+    plt.xticks([])
+    plt.yticks([])
+    img = np.asarray(Image.fromarray(plt.imread(img_file)).resize((512, 512)))
+    plt.imshow(img)
+
+
+def get_random_image(img_groups, group_names, gid):
+    gname = group_names[gid]
+    photos = img_groups[gname]
+    pid = np.random.choice(np.arange(len(photos)), size=1)[0]
+    pname = photos[pid]
+    return gname + pname + ".jpg"
+
+
+def create_triples(image_dir):
+    img_groups = {}
+    for img_file in os.listdir(image_dir):
+        prefix, suffix = img_file.split(".")
+        gid, pid = prefix[0:4], prefix[4:]
+        if gid in img_groups:
+            img_groups[gid].append(pid)
+        else:
+            img_groups[gid] = [pid]
+    pos_triples, neg_triples = [], []
+    # positive pairs are any combination of images in same group
+    for key in img_groups.keys():
+        triples = [(key + x[0] + ".jpg", key + x[1] + ".jpg", 1)
+                   for x in itertools.combinations(img_groups[key], 2)]
+        pos_triples.extend(triples)
+    # need equal number of negative examples
+    group_names = list(img_groups.keys())
+    # pos:neg == 1:1
+    for i in range(len(pos_triples)):
+        g1, g2 = np.random.choice(np.arange(len(group_names)), size=2, replace=False)
+        left = get_random_image(img_groups, group_names, g1)
+        right = get_random_image(img_groups, group_names, g2)
+        neg_triples.append((left, right, 0))
+    pos_triples.extend(neg_triples)
+    shuffle(pos_triples)
+    return pos_triples
+
+
+def load_image(image_name, imagenet=False):
+    if image_name not in image_cache:
+        image = plt.imread(os.path.join(IMAGE_DIR, image_name)).astype(np.float32)
+        image = image.astype(np.uint8)
+        image = np.asarray(Image.fromarray(image).resize((224, 224)))
+        if imagenet:
+            image = imagenet_utils.preprocess_input(image)
+        else:
+            image = np.divide(image, 256)
+        image_cache[image_name] = image
+    return image_cache[image_name]
+
+
+def generate_image_triples_batch(image_triples, batch_size, shuffle=False):
+    while True:
+        # loop once per epoch
+        if shuffle:
+            indices = np.random.permutation(np.arange(len(image_triples)))
+        else:
+            indices = np.arange(len(image_triples))
+        shuffled_triples = [image_triples[ix] for ix in indices]
+        num_batches = len(shuffled_triples) // batch_size
+        for bid in range(num_batches):
+            # loop once per batch
+            images_left, images_right, labels = [], [], []
+            batch = shuffled_triples[bid * batch_size: (bid + 1) * batch_size]
+            for i in range(batch_size):
+                lhs, rhs, label = batch[i]
+                images_left.append(load_image(lhs, imagenet=True))
+                images_right.append(load_image(rhs))
+                labels.append(label)
+            Xlhs = np.array(images_left)
+            Xrhs = np.array(images_right)
+            Y = np_utils.to_categorical(np.array(labels), num_classes=2)
+            yield ([Xlhs, Xrhs], Y)
+
+
+def train_test_split(triples, splits):
+    assert sum(splits) == 1.0
+    split_pts = np.cumsum(np.array([0.] + splits))
+    indices = np.random.permutation(np.arange(len(triples)))
+    shuffled_triples = [triples[i] for i in indices]
+    data_splits = []
+    for sid in range(len(splits)):
+        start = int(split_pts[sid] * len(triples))
+        end = int(split_pts[sid + 1] * len(triples))
+        data_splits.append(shuffled_triples[start:end])
+    return data_splits
+
+
+def batch_to_vectors(batch, vec_size, vec_dict):
+    X1 = np.zeros((len(batch), vec_size))
+    X2 = np.zeros((len(batch), vec_size))
+    Y = np.zeros((len(batch), 2))
+    for tid in range(len(batch)):
+        X1[tid] = vec_dict[batch[tid][0]]
+        X2[tid] = vec_dict[batch[tid][1]]
+        Y[tid] = [1, 0] if batch[tid][2] == 0 else [0, 1]
+    return ([X1, X2], Y)
+
+
+def data_generator(triples, vec_size, vec_dict, batch_size=32):
+    while True:
+        # shuffle once per batch
+        indices = np.random.permutation(np.arange(len(triples)))
+        num_batches = len(triples) // batch_size
+        for bid in range(num_batches):
+            batch_indices = indices[bid * batch_size: (bid + 1) * batch_size]
+            batch = [triples[i] for i in batch_indices]
+            yield batch_to_vectors(batch, vec_size, vec_dict)
+
+
+if __name__ == '__main__':
+    show_img(131, os.path.join(IMAGE_DIR, "115200.jpg"), "original")
+    show_img(132, os.path.join(IMAGE_DIR, "115201.jpg"), "similar")
+    show_img(133, os.path.join(IMAGE_DIR, "123700.jpg"), "different")
+    plt.tight_layout()
+    plt.show()
+
+    triples_data = create_triples(IMAGE_DIR)
+
+    print("# image triples:", len(triples_data))
+    print([x for x in triples_data[0:5]])
diff --git a/cv/holiday_similarity/eval_utils.py b/cv/holiday_similarity/eval_utils.py
new file mode 100644
index 0000000..b83125e
--- /dev/null
+++ b/cv/holiday_similarity/eval_utils.py
@@ -0,0 +1,24 @@
+import numpy as np
+from sklearn.metrics import accuracy_score, confusion_matrix, classification_report
+
+
+def evaluate_model(model, test_gen, test_triples, batch_size):
+    # model_name = os.path.basename(model_file)
+    # model = load_model(model_file)
+    # print("=== Evaluating model: {:s} ===".format(model_name))
+    print("=== Evaluating model")
+    ytrue, ypred = [], []
+    num_test_steps = len(test_triples) // batch_size
+    for i in range(num_test_steps):
+        # (X1, X2), Y = test_gen.next()
+        (X1, X2), Y = next(test_gen)
+        Y_ = model.predict([X1, X2])
+        ytrue.extend(np.argmax(Y, axis=1).tolist())
+        ypred.extend(np.argmax(Y_, axis=1).tolist())
+    accuracy = accuracy_score(ytrue, ypred)
+    print("\nAccuracy: {:.3f}".format(accuracy))
+    print("\nConfusion Matrix")
+    print(confusion_matrix(ytrue, ypred))
+    print("\nClassification Report")
+    print(classification_report(ytrue, ypred))
+    return accuracy
diff --git a/cv/holiday_similarity/generate_image_features.py b/cv/holiday_similarity/generate_image_features.py
new file mode 100644
index 0000000..6c26995
--- /dev/null
+++ b/cv/holiday_similarity/generate_image_features.py
@@ -0,0 +1,65 @@
+import os
+
+import matplotlib.pyplot as plt
+import numpy as np
+from PIL import Image
+from keras.applications import imagenet_utils
+from keras.applications import resnet50
+from keras.models import Model
+
+IMAGE_DIR = '/Users/chunhuizhang/workspaces/00_datasets/images/INRIA Holidays dataset /jpg'
+DATA_DIR = './data'
+
+
+def image_batch_generator(image_names, batch_size):
+    num_batches = len(image_names) // batch_size
+    for i in range(num_batches):
+        batch = image_names[i * batch_size: (i + 1) * batch_size]
+        yield batch
+    batch = image_names[(i + 1) * batch_size:]
+    yield batch
+
+
+def vectorize_images(image_dir, image_size, preprocessor,
+                     model, vector_file, batch_size=32):
+    image_names = os.listdir(image_dir)
+    num_vecs = 0
+    fvec = open(vector_file, "w")
+    for image_batch in image_batch_generator(image_names, batch_size):
+        batched_images = []
+        for image_name in image_batch:
+            image = plt.imread(os.path.join(image_dir, image_name))
+            # image = imresize(image, (image_size, image_size))
+            image = np.asarray(Image.fromarray(image).resize((image_size, image_size)))
+            batched_images.append(image)
+        X = preprocessor(np.array(batched_images, dtype="float32"))
+        vectors = model.predict(X)
+        for i in range(vectors.shape[0]):
+            if num_vecs % 100 == 0:
+                print("{:d}/{:d} vectors generated".format(num_vecs, vectors.shape[0]))
+            image_vector = ",".join(["{:.5e}".format(v) for v in vectors[i].tolist()])
+            # print(image_batch[i], image_vector)
+            # print(type(image_batch[i]), type(image_vector))
+            fvec.write("{:s}\t{:s}\n".format(image_batch[i], image_vector))
+            num_vecs += 1
+    print("{:d} vectors generated".format(num_vecs))
+    fvec.close()
+
+
+def generate_features(model, image_size, vector_file):
+    model = Model(input=model.input,
+                  output=model.get_layer("avg_pool").output)
+    preprocessor = imagenet_utils.preprocess_input
+
+    vectorize_images(IMAGE_DIR, image_size, preprocessor, model, vector_file)
+
+
+if __name__ == '__main__':
+    IMAGE_SIZE = 224
+    # vgg16_model = vgg16.VGG16(weights="imagenet", include_top=True)
+    # VECTOR_FILE = os.path.join(DATA_DIR, "vgg19-vectors.tsv")
+    # generate_features(vgg16_model, IMAGE_SIZE, VECTOR_FILE)
+
+    VECTOR_FILE = os.path.join(DATA_DIR, "resnet-vectors.tsv")
+    resnet_model = resnet50.ResNet50(weights="imagenet", include_top=True)
+    generate_features(resnet_model, IMAGE_SIZE, VECTOR_FILE)
diff --git a/cv/holiday_similarity/image_vectors_utils.py b/cv/holiday_similarity/image_vectors_utils.py
new file mode 100644
index 0000000..1883ac0
--- /dev/null
+++ b/cv/holiday_similarity/image_vectors_utils.py
@@ -0,0 +1,125 @@
+from sklearn.externals import joblib
+import itertools
+import os
+
+import numpy as np
+from sklearn import model_selection
+from sklearn.externals import joblib
+from sklearn.metrics import accuracy_score, confusion_matrix, classification_report
+from sklearn.model_selection import KFold
+
+DATA_DIR = './data'
+IMAGE_DIR = '/Users/chunhuizhang/workspaces/00_datasets/images/INRIA Holidays dataset /jpg'
+
+
+def get_holiday_triples(image_dir):
+    image_groups = {}
+    for image_name in os.listdir(image_dir):
+        base_name = image_name[0:-4]
+        group_name = base_name[0:4]
+        if group_name in image_groups:
+            image_groups[group_name].append(image_name)
+        else:
+            image_groups[group_name] = [image_name]
+    num_sims = 0
+    image_triples = []
+    group_list = sorted(list(image_groups.keys()))
+    for i, g in enumerate(group_list):
+        if num_sims % 100 == 0:
+            print("Generated {:d} pos + {:d} neg = {:d} total image triples"
+                  .format(num_sims, num_sims, 2 * num_sims))
+        images_in_group = image_groups[g]
+        sim_pairs_it = itertools.combinations(images_in_group, 2)
+        # for each similar pair, generate a corresponding different pair
+        for ref_image, sim_image in sim_pairs_it:
+            image_triples.append((ref_image, sim_image, 1))
+            num_sims += 1
+            while True:
+                j = np.random.randint(low=0, high=len(group_list), size=1)[0]
+                if j != i:
+                    break
+            dif_image_candidates = image_groups[group_list[j]]
+            k = np.random.randint(low=0, high=len(dif_image_candidates), size=1)[0]
+            dif_image = dif_image_candidates[k]
+            image_triples.append((ref_image, dif_image, 0))
+    print("Generated {:d} pos + {:d} neg = {:d} total image triples"
+          .format(num_sims, num_sims, 2 * num_sims))
+    return image_triples
+
+
+def load_vectors(vector_file):
+    vec_dict = {}
+    fvec = open(vector_file, "r")
+    for line in fvec:
+        image_name, image_vec = line.strip().split("\t")
+        vec = np.array([float(v) for v in image_vec.split(",")])
+        vec_dict[image_name] = vec
+    fvec.close()
+    return vec_dict
+
+
+def preprocess_data(vector_file, train_size=0.7):
+    xdata, ydata = [], []
+    vec_dict = load_vectors(vector_file)
+    for image_triple in image_triples:
+        X1 = vec_dict[image_triple[0]]
+        X2 = vec_dict[image_triple[1]]
+        # xdata.append(np.multiply(X1, X2) / (np.linalg.norm(X1, 2) * np.linalg.norm(X2, 2)))
+        # xdata.append(np.power(np.subtract(X1, X2), 2))
+        xdata.append(np.abs(np.subtract(X1, X2)))
+        ydata.append(image_triple[2])
+    X, y = np.array(xdata), np.array(ydata)
+    Xtrain, Xtest, ytrain, ytest = model_selection.train_test_split(X, y, train_size=train_size)
+    return Xtrain, Xtest, ytrain, ytest
+
+
+def cross_validate(X, y, clf, k=10):
+    best_score, best_clf = 0.0, None
+    kfold = KFold(k)
+    for kid, (train, test) in enumerate(kfold.split(X, y)):
+        Xtrain, Xtest, ytrain, ytest = X[train], X[test], y[train], y[test]
+        clf.fit(Xtrain, ytrain)
+        ytest_ = clf.predict(Xtest)
+        score = accuracy_score(ytest_, ytest)
+        print("fold {:d}, score: {:.3f}".format(kid, score))
+        if score > best_score:
+            best_score = score
+            best_clf = clf
+    return best_clf, best_score
+
+
+def test_report(clf, Xtest, ytest):
+    ytest_ = clf.predict(Xtest)
+    print("\nAccuracy Score: {:.3f}".format(accuracy_score(ytest_, ytest)))
+    print("\nConfusion Matrix")
+    print(confusion_matrix(ytest_, ytest))
+    print("\nClassification Report")
+    print(classification_report(ytest_, ytest))
+
+
+# def get_model_file(data_dir, vec_name, clf_name):
+#     return os.path.join(data_dir, "models", "{:s}-{:s}-dot.pkl"
+#                         .format(vec_name, clf_name))
+
+def get_model_file(data_dir, vector_name, merge_mode, borf):
+    return os.path.join(data_dir, "models", "{:s}-{:s}-{:s}.h5"
+                        .format(vector_name, merge_mode, borf))
+
+
+def save_model(model, model_file):
+    joblib.dump(model, model_file)
+
+# image_triples = get_holiday_triples(IMAGE_DIR)
+#
+# NUM_VECTORIZERS = 5
+# NUM_CLASSIFIERS = 4
+# scores = np.zeros((NUM_VECTORIZERS, NUM_CLASSIFIERS))
+#
+# VECTOR_FILE = os.path.join(DATA_DIR, "vgg19-vectors.tsv")
+# Xtrain, Xtest, ytrain, ytest = preprocess_data(VECTOR_FILE)
+# print(Xtrain.shape, Xtest.shape, ytrain.shape, ytest.shape)
+# clf = XGBClassifier()
+# best_clf, best_score = cross_validate(Xtrain, ytrain, clf)
+# scores[0, 2] = best_score
+# test_report(best_clf, Xtest, ytest)
+# save_model(best_clf, get_model_file(DATA_DIR, "vgg19", "xgb"))
diff --git a/cv/holiday_similarity/main.py b/cv/holiday_similarity/main.py
new file mode 100644
index 0000000..a292aab
--- /dev/null
+++ b/cv/holiday_similarity/main.py
@@ -0,0 +1,28 @@
+from cv.holiday_similarity import vis_utils
+from cv.holiday_similarity.data_utils import *
+from cv.holiday_similarity.prepare_models import e2e_pretrained_network
+
+BATCH_SIZE = 64
+
+triples_data = create_triples(IMAGE_DIR)
+split_point = int(len(triples_data) * 0.7)
+triples_train, triples_test = triples_data[0:split_point], triples_data[split_point:]
+
+NUM_EPOCHS = 10
+
+image_cache = {}
+train_gen = generate_image_triples_batch(triples_train, BATCH_SIZE, shuffle=True)
+val_gen = generate_image_triples_batch(triples_test, BATCH_SIZE, shuffle=False)
+
+num_train_steps = len(triples_train) // BATCH_SIZE
+num_val_steps = len(triples_test) // BATCH_SIZE
+
+# nn = e2e_network()
+nn = e2e_pretrained_network()
+history = nn.fit_generator(train_gen,
+                           steps_per_epoch=num_train_steps,
+                           epochs=NUM_EPOCHS,
+                           validation_data=val_gen,
+                           validation_steps=num_val_steps)
+
+vis_utils.plot_training_curve(history)
diff --git a/cv/holiday_similarity/model_utils.py b/cv/holiday_similarity/model_utils.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/cv/holiday_similarity/model_utils.py
diff --git a/cv/holiday_similarity/prepare_models.py b/cv/holiday_similarity/prepare_models.py
new file mode 100644
index 0000000..22f4958
--- /dev/null
+++ b/cv/holiday_similarity/prepare_models.py
@@ -0,0 +1,107 @@
+import keras.backend as K
+from keras import layers, models
+from keras.applications import vgg16, vgg19, inception_v3
+from keras.models import Sequential
+from keras.utils import plot_model
+
+
+def create_base_network(input_shape):
+    seq = Sequential()
+    # CONV => RELU => POOL
+    # 224, ==> ceil(224/1) == 224
+    seq.add(layers.Conv2D(20, kernel_size=5, padding="same", input_shape=input_shape))
+    seq.add(layers.Activation("relu"))
+    # 45 ==> ceil((224-(2-1))/2) ==> 112
+    seq.add(layers.MaxPooling2D(pool_size=(2, 2), strides=(2, 2)))
+    # CONV => RELU => POOL
+    seq.add(layers.Conv2D(50, kernel_size=5, padding="same"))
+    seq.add(layers.Activation("relu"))
+    # (112-(2-1))/2 ==> 56
+    seq.add(layers.MaxPooling2D(pool_size=(2, 2), strides=(2, 2)))
+    # Flatten => RELU
+    seq.add(layers.Flatten())
+    # (None, 500)
+    seq.add(layers.Dense(500))
+
+    return seq
+
+
+def pretrained_network():
+    pass
+
+
+def cosine_distance(vecs, normalize=False):
+    x, y = vecs
+    if normalize:
+        x = K.l2_normalize(x, axis=0)
+        y = K.l2_normalize(y, axis=0)
+    return K.prod(K.stack([x, y], axis=1), axis=1)
+
+
+def cosine_distance_output_shape(shapes):
+    return shapes[0]
+
+
+def e2e_network(nn=create_base_network):
+    input_shape = (224, 224, 3)
+    base_network = nn(input_shape)
+
+    image_left = layers.Input(shape=input_shape)
+    image_right = layers.Input(shape=input_shape)
+
+    left_vec = base_network(image_left)
+    right_vec = base_network(image_right)
+
+    dist = layers.Lambda(cosine_distance, output_shape=cosine_distance_output_shape)([left_vec, right_vec])
+
+    fc1 = layers.Dense(128, kernel_initializer="glorot_uniform")(dist)
+    fc1 = layers.Dropout(0.2)(fc1)
+    fc1 = layers.Activation("relu")(fc1)
+
+    pred = layers.Dense(2, kernel_initializer="glorot_uniform")(fc1)
+    pred = layers.Activation("softmax")(pred)
+
+    model = models.Model(inputs=[image_left, image_right], outputs=pred)
+
+    model.compile(loss="categorical_crossentropy", optimizer="adam", metrics=["accuracy"])
+    return model
+
+
+def e2e_pretrained_network():
+    vgg16_model = vgg16.VGG16(weights="imagenet", include_top=True)
+
+    # vgg19_model = vgg19.VGG19(weights="imagenet", include_top=True)
+    inception_model = inception_v3.InceptionV3(weights="imagenet", include_top=True)
+
+    input_shape = (224, 224, 3)
+    image_left = layers.Input(shape=input_shape)
+    image_right = layers.Input(shape=input_shape)
+
+    base_model = models.Model(input=vgg16_model.input, output=vgg16_model.get_layer('fc2').output)
+    left_vec = base_model(image_left)
+    right_vec = base_model(image_right)
+    dist = layers.Lambda(cosine_distance, output_shape=cosine_distance_output_shape)([left_vec, right_vec])
+    fc1 = layers.Dense(128, kernel_initializer="glorot_uniform")(dist)
+    fc1 = layers.Dropout(0.2)(fc1)
+    fc1 = layers.Activation("relu")(fc1)
+
+    pred = layers.Dense(2, kernel_initializer="glorot_uniform")(fc1)
+    pred = layers.Activation("softmax")(pred)
+
+    model = models.Model(inputs=[image_left, image_right], outputs=pred)
+
+    model.compile(loss="categorical_crossentropy", optimizer="adam", metrics=["accuracy"])
+    return model
+
+
+def concat_vectors(vector_size, ):
+    input_1 = layers.Input(shape=(vector_size,))
+    input_2 = layers.Input(shape=(vector_size,))
+    layers.merge.Concatenate(input_1)
+
+
+if __name__ == '__main__':
+    vgg19_model = vgg19.VGG19(weights="imagenet", include_top=True)
+    inception_model = inception_v3.InceptionV3(weights="imagenet", include_top=True)
+    model = e2e_network()
+    plot_model(inception_model, to_file='inception_model.png', show_layer_names=True, show_shapes=True)
diff --git a/cv/holiday_similarity/pretrained-vec-nn-classifier.py b/cv/holiday_similarity/pretrained-vec-nn-classifier.py
new file mode 100644
index 0000000..e8fff09
--- /dev/null
+++ b/cv/holiday_similarity/pretrained-vec-nn-classifier.py
@@ -0,0 +1,171 @@
+from keras import backend as K
+from keras import layers, models, callbacks, utils
+
+from cv.holiday_similarity.data_utils import *
+from cv.holiday_similarity.image_vectors_utils import *
+
+DATA_DIR = "./data"
+IMAGE_DIR = '/Users/chunhuizhang/workspaces/00_datasets/images/INRIA Holidays dataset /jpg'
+
+BATCH_SIZE = 32
+NUM_EPOCHS = 10
+
+
+def e2e_model_concat(vec_size):
+    input_1 = layers.Input(shape=(vec_size,))
+    input_2 = layers.Input(shape=(vec_size,))
+
+    merged = layers.merge.Concatenate(axis=-1)([input_1, input_2])
+
+    fc1 = layers.Dense(512, kernel_initializer="glorot_uniform")(merged)
+    fc1 = layers.Dropout(0.2)(fc1)
+    fc1 = layers.Activation("relu")(fc1)
+
+    fc2 = layers.Dense(128, kernel_initializer="glorot_uniform")(fc1)
+    fc2 = layers.Dropout(0.2)(fc2)
+    fc2 = layers.Activation("relu")(fc2)
+
+    pred = layers.Dense(2, kernel_initializer="glorot_uniform")(fc2)
+    pred = layers.Activation("softmax")(pred)
+    model = models.Model(inputs=[input_1, input_2], outputs=pred)
+    model.compile(optimizer="adam", loss="categorical_crossentropy", metrics=["accuracy"])
+    utils.plot_model(model, to_file='./data/images/concat.png', show_shapes=True, show_layer_names=True)
+    return model
+
+
+def e2e_model_dot(vec_size):
+    def cosine_distance(vecs, normalize=False):
+        x, y = vecs
+        if normalize:
+            x = K.l2_normalize(x, axis=0)
+            y = K.l2_normalize(x, axis=0)
+        return K.prod(K.stack([x, y], axis=1), axis=1)
+
+    def cosine_distance_output_shape(shapes):
+        return shapes[0]
+
+    input_1 = layers.Input(shape=(vec_size,))
+    input_2 = layers.Input(shape=(vec_size,))
+
+    merged = layers.Lambda(cosine_distance,
+                           output_shape=cosine_distance_output_shape)([input_1, input_2])
+
+    fc1 = layers.Dense(512, kernel_initializer="glorot_uniform")(merged)
+    fc1 = layers.Dropout(0.2)(fc1)
+    fc1 = layers.Activation("relu")(fc1)
+
+    fc2 = layers.Dense(128, kernel_initializer="glorot_uniform")(fc1)
+    fc2 = layers.Dropout(0.2)(fc2)
+    fc2 = layers.Activation("relu")(fc2)
+
+    pred = layers.Dense(2, kernel_initializer="glorot_uniform")(fc2)
+    pred = layers.Activation("softmax")(pred)
+    model = models.Model(inputs=[input_1, input_2], outputs=pred)
+    model.compile(optimizer="adam", loss="categorical_crossentropy", metrics=["accuracy"])
+    utils.plot_model(model, to_file='./data/images/dot.png', show_shapes=True, show_layer_names=True)
+    return model
+
+
+def e2e_model_l1(vec_size):
+    def absdiff(vecs):
+        x, y = vecs
+        return K.abs(K.sum(K.stack([x, -y], axis=1), axis=1))
+
+    def absdiff_output_shape(shapes):
+        return shapes[0]
+
+    input_1 = layers.Input(shape=(vec_size,))
+    input_2 = layers.Input(shape=(vec_size,))
+    merged = layers.Lambda(absdiff, output_shape=absdiff_output_shape)([input_1, input_2])
+
+    fc1 = layers.Dense(512, kernel_initializer="glorot_uniform")(merged)
+    fc1 = layers.Dropout(0.2)(fc1)
+    fc1 = layers.Activation("relu")(fc1)
+
+    fc2 = layers.Dense(128, kernel_initializer="glorot_uniform")(fc1)
+    fc2 = layers.Dropout(0.2)(fc2)
+    fc2 = layers.Activation("relu")(fc2)
+
+    pred = layers.Dense(2, kernel_initializer="glorot_uniform")(fc2)
+    pred = layers.Activation("softmax")(pred)
+    model = models.Model(inputs=[input_1, input_2], outputs=pred)
+    model.compile(optimizer="adam", loss="categorical_crossentropy", metrics=["accuracy"])
+    utils.plot_model(model, to_file='./data/images/l1.png', show_shapes=True, show_layer_names=True)
+    return model
+
+
+def e2e_model_l2(vec_size):
+    def euclidean_distance(vecs):
+        x, y = vecs
+        return K.sqrt(K.sum(K.stack([K.square(x), -K.square(y)], axis=1), axis=1))
+
+    def euclidean_distance_output_shape(shapes):
+        xshape, yshape = shapes
+        return xshape
+
+    input_1 = layers.Input(shape=(vec_size,))
+    input_2 = layers.Input(shape=(vec_size,))
+    merged = layers.Lambda(euclidean_distance,
+                           output_shape=euclidean_distance_output_shape)([input_1, input_2])
+
+    fc1 = layers.Dense(512, kernel_initializer="glorot_uniform")(merged)
+    fc1 = layers.Dropout(0.2)(fc1)
+    fc1 = layers.Activation("relu")(fc1)
+
+    fc2 = layers.Dense(128, kernel_initializer="glorot_uniform")(fc1)
+    fc2 = layers.Dropout(0.2)(fc2)
+    fc2 = layers.Activation("relu")(fc2)
+
+    pred = layers.Dense(2, kernel_initializer="glorot_uniform")(fc2)
+    pred = layers.Activation("softmax")(pred)
+
+    model = models.Model(inputs=[input_1, input_2], outputs=pred)
+    model.compile(optimizer="adam", loss="categorical_crossentropy", metrics=["accuracy"])
+    utils.plot_model(model, to_file='./data/images/l2.png', show_shapes=True, show_layer_names=True)
+    return model
+
+
+if __name__ == '__main__':
+    image_triples = get_holiday_triples(IMAGE_DIR)
+    train_triples, val_triples, test_triples = train_test_split(image_triples,
+                                                                splits=[0.7, 0.1, 0.2])
+    print(len(train_triples), len(val_triples), len(test_triples))
+
+    VECTOR_SIZE = 2048
+    VECTOR_FILE = os.path.join(DATA_DIR, "resnet-vectors.tsv")
+
+    vec_dict = load_vectors(VECTOR_FILE)
+
+    train_gen = data_generator(train_triples, VECTOR_SIZE, vec_dict, BATCH_SIZE)
+    val_gen = data_generator(val_triples, VECTOR_SIZE, vec_dict, BATCH_SIZE)
+
+    # model_name = get_model_file(DATA_DIR, 'resnet', 'dot', 'best')
+    # model_name = get_model_file(DATA_DIR, 'resnet', 'concat', 'best')
+    model_name = get_model_file(DATA_DIR, 'resnet', 'l2', 'best')
+
+    checkpoint = callbacks.ModelCheckpoint(model_name, save_best_only=True)
+    train_steps_per_epoch = len(train_triples) // BATCH_SIZE
+    val_steps_per_epoch = len(val_triples) // BATCH_SIZE
+
+    # model = e2e_model_concat(VECTOR_SIZE)
+    # model = e2e_model_dot(VECTOR_SIZE)
+    # model = e2e_model_l1(VECTOR_SIZE)
+    e2e_model_l2(VECTOR_SIZE)
+
+    # history = model.fit_generator(train_gen, steps_per_epoch=train_steps_per_epoch,
+    #                               epochs=NUM_EPOCHS,
+    #                               validation_data=val_gen, validation_steps=val_steps_per_epoch,
+    #                               callbacks=[checkpoint])
+    #
+    # plot_training_curve(history)
+    #
+    # final_model_name = get_model_file(DATA_DIR, "resnet", "l2", 'final')
+    # model.save(final_model_name)
+    #
+    # test_gen = data_generator(test_triples, VECTOR_SIZE, vec_dict, BATCH_SIZE)
+    # final_accuracy = evaluate_model(models.load_model(final_model_name), test_gen, test_triples, BATCH_SIZE)
+    #
+    # test_gen = data_generator(test_triples, VECTOR_SIZE, vec_dict, BATCH_SIZE)
+    # best_accuracy = evaluate_model(models.load_model(model_name), test_gen, test_triples, BATCH_SIZE)
+    #
+    # scores = best_accuracy if best_accuracy > final_accuracy else final_accuracy
diff --git a/cv/holiday_similarity/siamese-finetune.py b/cv/holiday_similarity/siamese-finetune.py
new file mode 100644
index 0000000..9cd3dbb
--- /dev/null
+++ b/cv/holiday_similarity/siamese-finetune.py
@@ -0,0 +1,98 @@
+from keras.applications import resnet50
+from PIL import Image
+from keras import models, callbacks
+from keras.applications import imagenet_utils
+from keras.applications import resnet50
+from keras.preprocessing.image import ImageDataGenerator
+from sklearn import model_selection
+
+from cv.holiday_similarity.data_utils import *
+from cv.holiday_similarity.vis_utils import *
+
+
+def e2e_network():
+    inception_1 = resnet50.ResNet50(weights="imagenet", include_top=True)
+    inception_2 = resnet50.ResNet50(weights="imagenet", include_top=True)
+
+    for layer in inception_1.layers:
+        layer.trainable = False
+        layer.name = layer.name + "_1"
+    for layer in inception_2.layers:
+        layer.trainable = False
+        layer.name = layer.name + "_2"
+
+    vector_1 = inception_1.get_layer("avg_pool_1").output
+    vector_2 = inception_2.get_layer("avg_pool_2").output
+
+    sim_head = models.load_model(os.path.join(DATA_DIR, "models", "resnet-dot-best.h5"))
+    for layer in sim_head.layers:
+        print(layer.name, layer.input_shape, layer.output_shape)
+
+    prediction = sim_head([vector_1, vector_2])
+
+    model = models.Model(inputs=[inception_1.input, inception_2.input], outputs=prediction)
+    model.compile(optimizer="adam", loss="categorical_crossentropy", metrics=["accuracy"])
+
+    return model
+
+
+def load_image_cache(image_cache, image_filename):
+    image = plt.imread(os.path.join(IMAGE_DIR, image_filename))
+    image = np.asarray(Image.fromarray(image).resize((224, 224)))
+    image = image.astype("float32")
+    image = imagenet_utils.preprocess_input(image)
+    image_cache[image_filename] = image
+
+
+def generate_image_cache(triples_data):
+    image_cache = {}
+    num_pairs = len(triples_data)
+    for i, (image_filename_l, image_filename_r, _) in enumerate(triples_data):
+        if i % 1000 == 0:
+            print("images from {:d}/{:d} pairs loaded to cache".format(i, num_pairs))
+        if image_filename_l not in image_cache:
+            load_image_cache(image_cache, image_filename_l)
+        if image_filename_r not in image_cache:
+            load_image_cache(image_cache, image_filename_r)
+    return image_cache
+
+
+if __name__ == '__main__':
+    DATA_DIR = './data'
+    IMAGE_DIR = '/Users/chunhuizhang/workspaces/00_datasets/images/INRIA Holidays dataset /jpg'
+
+    BATCH_SIZE = 32
+    NUM_EPOCHS = 5
+    BEST_MODEL_FILE = os.path.join(DATA_DIR, "models", "resnet-ft-best.h5")
+    FINAL_MODEL_FILE = os.path.join(DATA_DIR, "models", "resnet-ft-final.h5")
+
+    triples_data = create_triples(IMAGE_DIR)
+    triples_data_trainval, triples_data_test = model_selection.train_test_split(triples_data, train_size=0.8)
+    triples_data_train, triples_data_val = model_selection.train_test_split(triples_data_trainval, train_size=0.9)
+    print(len(triples_data_train), len(triples_data_val), len(triples_data_test))
+
+    datagen_args = dict(rotation_range=10,
+                        width_shift_range=0.2,
+                        height_shift_range=0.2,
+                        zoom_range=0.2)
+    datagens = [ImageDataGenerator(**datagen_args),
+                ImageDataGenerator(**datagen_args)]
+
+    image_cache = generate_image_cache(triples_data)
+
+    train_pair_gen = pair_generator(triples_data_train, image_cache, datagens, BATCH_SIZE)
+    val_pair_gen = pair_generator(triples_data_val, image_cache, None, BATCH_SIZE)
+
+    num_train_steps = len(triples_data_train) // BATCH_SIZE
+    num_val_steps = len(triples_data_val) // BATCH_SIZE
+
+    model = e2e_network()
+    checkpoint = callbacks.ModelCheckpoint(filepath=BEST_MODEL_FILE, save_best_only=True)
+    history = model.fit_generator(train_pair_gen,
+                                  steps_per_epoch=num_train_steps,
+                                  epochs=NUM_EPOCHS,
+                                  validation_data=val_pair_gen,
+                                  validation_steps=num_val_steps,
+                                  callbacks=[checkpoint])
+
+    plot_training_curve(history)
diff --git a/cv/holiday_similarity/vis_utils.py b/cv/holiday_similarity/vis_utils.py
new file mode 100644
index 0000000..0910364
--- /dev/null
+++ b/cv/holiday_similarity/vis_utils.py
@@ -0,0 +1,19 @@
+import matplotlib.pyplot as plt
+
+
+def plot_training_curve(history):
+    # print(history.history.keys())
+    plt.subplot(211)
+    plt.title("Loss")
+    plt.plot(history.history["loss"], color="r", label="train")
+    plt.plot(history.history["val_loss"], color="b", label="validation")
+    plt.legend(loc="best")
+
+    plt.subplot(212)
+    plt.title("Accuracy")
+    plt.plot(history.history["accuracy"], color="r", label="train")
+    plt.plot(history.history["val_accuracy"], color="b", label="validation")
+    plt.legend(loc="best")
+
+    plt.tight_layout()
+    plt.show()