Fisheries competition

In this notebook we're going to investigate a range of different architectures for the Kaggle fisheries competition. The video states that vgg.py and vgg_ft() from utils.py have been updated to include VGG with batch normalization, but this is not the case. We've instead created a new file vgg_bn.py and an additional method vgg_ft_bn() (which is already in utils.py) which we use in this notebook.


In [2]:
from theano.sandbox import cuda

In [3]:
%matplotlib inline
import utils; reload(utils)
from utils import *
from __future__ import division, print_function

In [4]:
#path = "data/fish/sample/"
path = "data/fish/"
batch_size=64

In [5]:
batches = get_batches(path+'train', batch_size=batch_size)
val_batches = get_batches(path+'valid', batch_size=batch_size*2, shuffle=False)

(val_classes, trn_classes, val_labels, trn_labels, 
    val_filenames, filenames, test_filenames) = get_classes(path)


Found 3277 images belonging to 8 classes.
Found 500 images belonging to 8 classes.
Found 3277 images belonging to 8 classes.
Found 500 images belonging to 8 classes.
Found 1000 images belonging to 1 classes.

Sometimes it's helpful to have just the filenames, without the path.


In [6]:
raw_filenames = [f.split('/')[-1] for f in filenames]
raw_test_filenames = [f.split('/')[-1] for f in test_filenames]
raw_val_filenames = [f.split('/')[-1] for f in val_filenames]

Setup dirs

We create the validation and sample sets in the usual way.


In [ ]:
%cd data/fish
%cd train
%mkdir ../valid

In [ ]:
g = glob('*')
for d in g: os.mkdir('../valid/'+d)

g = glob('*/*.jpg')
shuf = np.random.permutation(g)
for i in range(500): os.rename(shuf[i], '../valid/' + shuf[i])

In [ ]:
%mkdir ../sample
%mkdir ../sample/train
%mkdir ../sample/valid

In [ ]:
from shutil import copyfile

g = glob('*')
for d in g: 
    os.mkdir('../sample/train/'+d)
    os.mkdir('../sample/valid/'+d)

In [ ]:
g = glob('*/*.jpg')
shuf = np.random.permutation(g)
for i in range(400): copyfile(shuf[i], '../sample/train/' + shuf[i])

%cd ../valid

g = glob('*/*.jpg')
shuf = np.random.permutation(g)
for i in range(200): copyfile(shuf[i], '../sample/valid/' + shuf[i])

%cd ..

In [6]:
%mkdir results
%mkdir sample/results
%cd ../..


/data/jhoward/fast-image/nbs/data/fish

Basic VGG

We start with our usual VGG approach. We will be using VGG with batch normalization. We explained how to add batch normalization to VGG in the imagenet_batchnorm notebook. VGG with batch normalization is implemented in vgg_bn.py, and there is a version of vgg_ft (our fine tuning function) with batch norm called vgg_ft_bn in utils.py.

Initial model

First we create a simple fine-tuned VGG model to be our starting point.


In [7]:
from vgg16bn import Vgg16BN
model = vgg_ft_bn(8)

In [8]:
trn = get_data(path+'train')
val = get_data(path+'valid')


Found 3277 images belonging to 8 classes.
Found 500 images belonging to 8 classes.

In [9]:
test = get_data(path+'test')


Found 1000 images belonging to 1 classes.

In [10]:
save_array(path+'results/trn.dat', trn)
save_array(path+'results/val.dat', val)

In [11]:
save_array(path+'results/test.dat', test)

In [45]:
trn = load_array(path+'results/trn.dat')
val = load_array(path+'results/val.dat')

In [54]:
test = load_array(path+'results/test.dat')

In [12]:
gen = image.ImageDataGenerator()

In [13]:
model.compile(optimizer=Adam(1e-3),
       loss='categorical_crossentropy', metrics=['accuracy'])

In [14]:
model.fit(trn, trn_labels, batch_size=batch_size, nb_epoch=3, validation_data=(val, val_labels))


Train on 3277 samples, validate on 500 samples
Epoch 1/3
3277/3277 [==============================] - 87s - loss: 2.8985 - acc: 0.4596 - val_loss: 1.0387 - val_acc: 0.7220
Epoch 2/3
3277/3277 [==============================] - 87s - loss: 1.6575 - acc: 0.6301 - val_loss: 0.6592 - val_acc: 0.8260
Epoch 3/3
3277/3277 [==============================] - 87s - loss: 1.2879 - acc: 0.6951 - val_loss: 0.4562 - val_acc: 0.8620
Out[14]:
<keras.callbacks.History at 0x7fb6d3d5e810>

In [15]:
model.save_weights(path+'results/ft1.h5')

Precompute convolutional output

We pre-compute the output of the last convolution layer of VGG, since we're unlikely to need to fine-tune those layers. (All following analysis will be done on just the pre-computed convolutional features.)


In [50]:
model.load_weights(path+'results/ft1.h5')

In [16]:
conv_layers,fc_layers = split_at(model, Convolution2D)

In [17]:
conv_model = Sequential(conv_layers)

In [18]:
conv_feat = conv_model.predict(trn)
conv_val_feat = conv_model.predict(val)

In [19]:
conv_test_feat = conv_model.predict(test)

In [20]:
save_array(path+'results/conv_val_feat.dat', conv_val_feat)
save_array(path+'results/conv_feat.dat', conv_feat)

In [21]:
save_array(path+'results/conv_test_feat.dat', conv_test_feat)

In [53]:
conv_feat = load_array(path+'results/conv_feat.dat')
conv_val_feat = load_array(path+'results/conv_val_feat.dat')

In [829]:
conv_test_feat = load_array(path+'results/conv_test_feat.dat')

In [22]:
conv_val_feat.shape


Out[22]:
(500, 512, 14, 14)

Train model

We can now create our first baseline model - a simple 3-layer FC net.


In [23]:
def get_bn_layers(p):
    return [
        MaxPooling2D(input_shape=conv_layers[-1].output_shape[1:]),
        BatchNormalization(axis=1),
        Dropout(p/4),
        Flatten(),
        Dense(512, activation='relu'),
        BatchNormalization(),
        Dropout(p),
        Dense(512, activation='relu'),
        BatchNormalization(),
        Dropout(p/2),
        Dense(8, activation='softmax')
    ]

In [24]:
p=0.6

In [25]:
bn_model = Sequential(get_bn_layers(p))
bn_model.compile(Adam(lr=0.001), loss='categorical_crossentropy', metrics=['accuracy'])

In [26]:
bn_model.fit(conv_feat, trn_labels, batch_size=batch_size, nb_epoch=3, 
             validation_data=(conv_val_feat, val_labels))


Train on 3277 samples, validate on 500 samples
Epoch 1/3
3277/3277 [==============================] - 2s - loss: 1.1471 - acc: 0.6570 - val_loss: 0.6800 - val_acc: 0.8720
Epoch 2/3
3277/3277 [==============================] - 1s - loss: 0.3055 - acc: 0.9057 - val_loss: 0.1853 - val_acc: 0.9480
Epoch 3/3
3277/3277 [==============================] - 1s - loss: 0.1909 - acc: 0.9439 - val_loss: 0.1124 - val_acc: 0.9740
Out[26]:
<keras.callbacks.History at 0x7fb67bedc190>

In [27]:
bn_model.optimizer.lr = 1e-4

In [28]:
bn_model.fit(conv_feat, trn_labels, batch_size=batch_size, nb_epoch=7, 
             validation_data=(conv_val_feat, val_labels))


Train on 3277 samples, validate on 500 samples
Epoch 1/7
3277/3277 [==============================] - 1s - loss: 0.1002 - acc: 0.9695 - val_loss: 0.1023 - val_acc: 0.9840
Epoch 2/7
3277/3277 [==============================] - 1s - loss: 0.0666 - acc: 0.9826 - val_loss: 0.0974 - val_acc: 0.9840
Epoch 3/7
3277/3277 [==============================] - 1s - loss: 0.0633 - acc: 0.9814 - val_loss: 0.1327 - val_acc: 0.9780
Epoch 4/7
3277/3277 [==============================] - 1s - loss: 0.0443 - acc: 0.9875 - val_loss: 0.1313 - val_acc: 0.9820
Epoch 5/7
3277/3277 [==============================] - 1s - loss: 0.0393 - acc: 0.9866 - val_loss: 0.1056 - val_acc: 0.9880
Epoch 6/7
3277/3277 [==============================] - 1s - loss: 0.0475 - acc: 0.9850 - val_loss: 0.1051 - val_acc: 0.9880
Epoch 7/7
3277/3277 [==============================] - 1s - loss: 0.0383 - acc: 0.9884 - val_loss: 0.1047 - val_acc: 0.9880
Out[28]:
<keras.callbacks.History at 0x7fb67bedc690>

In [30]:
bn_model.save_weights(path+'models/conv_512_6.h5')

In [31]:
bn_model.evaluate(conv_val_feat, val_labels)


500/500 [==============================] - 0s     
Out[31]:
[0.10466163465986028, 0.98799999952316286]

In [774]:
bn_model.load_weights(path+'models/conv_512_6.h5')

Multi-input

The images are of different sizes, which are likely to represent the boat they came from (since different boats will use different cameras). Perhaps this creates some data leakage that we can take advantage of to get a better Kaggle leaderboard position? To find out, first we create arrays of the file sizes for each image:


In [32]:
sizes = [PIL.Image.open(path+'train/'+f).size for f in filenames]
id2size = list(set(sizes))
size2id = {o:i for i,o in enumerate(id2size)}

In [33]:
import collections
collections.Counter(sizes)


Out[33]:
Counter({(1192, 670): 169,
         (1244, 700): 23,
         (1276, 718): 192,
         (1280, 720): 1880,
         (1280, 750): 520,
         (1280, 924): 51,
         (1280, 974): 344,
         (1334, 750): 28,
         (1518, 854): 37,
         (1732, 974): 33})

Then we one-hot encode them (since we want to treat them as categorical) and normalize the data.


In [34]:
trn_sizes_orig = to_categorical([size2id[o] for o in sizes], len(id2size))

In [35]:
raw_val_sizes = [PIL.Image.open(path+'valid/'+f).size for f in val_filenames]
val_sizes = to_categorical([size2id[o] for o in raw_val_sizes], len(id2size))

In [36]:
trn_sizes = trn_sizes_orig-trn_sizes_orig.mean(axis=0)/trn_sizes_orig.std(axis=0)
val_sizes = val_sizes-trn_sizes_orig.mean(axis=0)/trn_sizes_orig.std(axis=0)

To use this additional "meta-data", we create a model with multiple input layers - sz_inp will be our input for the size information.


In [37]:
p=0.6

In [38]:
inp = Input(conv_layers[-1].output_shape[1:])
sz_inp = Input((len(id2size),))
bn_inp = BatchNormalization()(sz_inp)

x = MaxPooling2D()(inp)
x = BatchNormalization(axis=1)(x)
x = Dropout(p/4)(x)
x = Flatten()(x)
x = Dense(512, activation='relu')(x)
x = BatchNormalization()(x)
x = Dropout(p)(x)
x = Dense(512, activation='relu')(x)
x = BatchNormalization()(x)
x = Dropout(p/2)(x)
x = merge([x,bn_inp], 'concat')
x = Dense(8, activation='softmax')(x)

When we compile the model, we have to specify all the input layers in an array.


In [39]:
model = Model([inp, sz_inp], x)
model.compile(Adam(lr=0.001), loss='categorical_crossentropy', metrics=['accuracy'])

And when we train the model, we have to provide all the input layers' data in an array.


In [40]:
model.fit([conv_feat, trn_sizes], trn_labels, batch_size=batch_size, nb_epoch=3, 
             validation_data=([conv_val_feat, val_sizes], val_labels))


Train on 3277 samples, validate on 500 samples
Epoch 1/3
3277/3277 [==============================] - 2s - loss: 1.1621 - acc: 0.6613 - val_loss: 0.6370 - val_acc: 0.8860
Epoch 2/3
3277/3277 [==============================] - 2s - loss: 0.3222 - acc: 0.8993 - val_loss: 0.2118 - val_acc: 0.9600
Epoch 3/3
3277/3277 [==============================] - 2s - loss: 0.1668 - acc: 0.9542 - val_loss: 0.1140 - val_acc: 0.9740
Out[40]:
<keras.callbacks.History at 0x7fb673834b50>

In [41]:
bn_model.optimizer.lr = 1e-4

In [42]:
bn_model.fit(conv_feat, trn_labels, batch_size=batch_size, nb_epoch=8, 
             validation_data=(conv_val_feat, val_labels))


Train on 3277 samples, validate on 500 samples
Epoch 1/8
3277/3277 [==============================] - 1s - loss: 0.0666 - acc: 0.9774 - val_loss: 0.0928 - val_acc: 0.9900
Epoch 2/8
3277/3277 [==============================] - 1s - loss: 0.0363 - acc: 0.9905 - val_loss: 0.0997 - val_acc: 0.9840
Epoch 3/8
3277/3277 [==============================] - 1s - loss: 0.0292 - acc: 0.9924 - val_loss: 0.0840 - val_acc: 0.9900
Epoch 4/8
3277/3277 [==============================] - 1s - loss: 0.0375 - acc: 0.9905 - val_loss: 0.0862 - val_acc: 0.9900
Epoch 5/8
3277/3277 [==============================] - 1s - loss: 0.0218 - acc: 0.9939 - val_loss: 0.1155 - val_acc: 0.9880
Epoch 6/8
3277/3277 [==============================] - 1s - loss: 0.0292 - acc: 0.9905 - val_loss: 0.1033 - val_acc: 0.9900
Epoch 7/8
3277/3277 [==============================] - 1s - loss: 0.0173 - acc: 0.9921 - val_loss: 0.1030 - val_acc: 0.9900
Epoch 8/8
3277/3277 [==============================] - 1s - loss: 0.0186 - acc: 0.9936 - val_loss: 0.1058 - val_acc: 0.9900
Out[42]:
<keras.callbacks.History at 0x7fb6738b0310>

The model did not show an improvement by using the leakage, other than in the early epochs. This is most likely because the information about what boat the picture came from is readily identified from the image itself, so the meta-data turned out not to add any additional information.

Bounding boxes & multi output

Import / view bounding boxes

A kaggle user has created bounding box annotations for each fish in each training set image. You can download them from here. We will see if we can utilize this additional information. First, we'll load in the data, and keep just the largest bounding box for each image.


In [44]:
import ujson as json

In [45]:
anno_classes = ['alb', 'bet', 'dol', 'lag', 'other', 'shark', 'yft']

In [48]:
bb_json = {}
for c in anno_classes:
    j = json.load(open('{}annos/{}_labels.json'.format(path, c), 'r'))
    for l in j:
        if 'annotations' in l.keys() and len(l['annotations'])>0:
            bb_json[l['filename'].split('/')[-1]] = sorted(
                l['annotations'], key=lambda x: x['height']*x['width'])[-1]

In [49]:
bb_json['img_04908.jpg']


Out[49]:
{u'class': u'rect',
 u'height': 246.75000000000074,
 u'width': 432.8700000000013,
 u'x': 465.3000000000014,
 u'y': 496.32000000000147}

In [50]:
file2idx = {o:i for i,o in enumerate(raw_filenames)}
val_file2idx = {o:i for i,o in enumerate(raw_val_filenames)}

For any images that have no annotations, we'll create an empty bounding box.


In [51]:
empty_bbox = {'height': 0., 'width': 0., 'x': 0., 'y': 0.}

In [52]:
for f in raw_filenames:
    if not f in bb_json.keys(): bb_json[f] = empty_bbox
for f in raw_val_filenames:
    if not f in bb_json.keys(): bb_json[f] = empty_bbox

Finally, we convert the dictionary into an array, and convert the coordinates to our resized 224x224 images.


In [53]:
bb_params = ['height', 'width', 'x', 'y']
def convert_bb(bb, size):
    bb = [bb[p] for p in bb_params]
    conv_x = (224. / size[0])
    conv_y = (224. / size[1])
    bb[0] = bb[0]*conv_y
    bb[1] = bb[1]*conv_x
    bb[2] = max(bb[2]*conv_x, 0)
    bb[3] = max(bb[3]*conv_y, 0)
    return bb

In [54]:
trn_bbox = np.stack([convert_bb(bb_json[f], s) for f,s in zip(raw_filenames, sizes)], 
                   ).astype(np.float32)
val_bbox = np.stack([convert_bb(bb_json[f], s) 
                   for f,s in zip(raw_val_filenames, raw_val_sizes)]).astype(np.float32)

Now we can check our work by drawing one of the annotations.


In [55]:
def create_rect(bb, color='red'):
    return plt.Rectangle((bb[2], bb[3]), bb[1], bb[0], color=color, fill=False, lw=3)

def show_bb(i):
    bb = val_bbox[i]
    plot(val[i])
    plt.gca().add_patch(create_rect(bb))

In [56]:
show_bb(0)


Create & train model

Since we're not allowed (by the kaggle rules) to manually annotate the test set, we'll need to create a model that predicts the locations of the bounding box on each image. To do so, we create a model with multiple outputs: it will predict both the type of fish (the 'class'), and the 4 bounding box coordinates. We prefer this approach to only predicting the bounding box coordinates, since we hope that giving the model more context about what it's looking for will help it with both tasks.


In [57]:
p=0.6

In [58]:
inp = Input(conv_layers[-1].output_shape[1:])
x = MaxPooling2D()(inp)
x = BatchNormalization(axis=1)(x)
x = Dropout(p/4)(x)
x = Flatten()(x)
x = Dense(512, activation='relu')(x)
x = BatchNormalization()(x)
x = Dropout(p)(x)
x = Dense(512, activation='relu')(x)
x = BatchNormalization()(x)
x = Dropout(p/2)(x)
x_bb = Dense(4, name='bb')(x)
x_class = Dense(8, activation='softmax', name='class')(x)

Since we have multiple outputs, we need to provide them to the model constructor in an array, and we also need to say what loss function to use for each. We also weight the bounding box loss function down by 1000x since the scale of the cross-entropy loss and the MSE is very different.


In [59]:
model = Model([inp], [x_bb, x_class])
model.compile(Adam(lr=0.001), loss=['mse', 'categorical_crossentropy'], metrics=['accuracy'],
             loss_weights=[.001, 1.])

In [60]:
model.fit(conv_feat, [trn_bbox, trn_labels], batch_size=batch_size, nb_epoch=3, 
             validation_data=(conv_val_feat, [val_bbox, val_labels]))


Train on 3277 samples, validate on 500 samples
Epoch 1/3
3277/3277 [==============================] - 2s - loss: 6.1604 - bb_loss: 5030.2780 - class_loss: 1.1302 - bb_acc: 0.4007 - class_acc: 0.6710 - val_loss: 4.8844 - val_bb_loss: 4078.7171 - val_class_loss: 0.8057 - val_bb_acc: 0.4500 - val_class_acc: 0.8400
Epoch 2/3
3277/3277 [==============================] - 1s - loss: 5.0668 - bb_loss: 4743.1687 - class_loss: 0.3237 - bb_acc: 0.4809 - class_acc: 0.9057 - val_loss: 4.1392 - val_bb_loss: 3909.2589 - val_class_loss: 0.2300 - val_bb_acc: 0.5020 - val_class_acc: 0.9500
Epoch 3/3
3277/3277 [==============================] - 1s - loss: 4.4301 - bb_loss: 4272.6528 - class_loss: 0.1574 - bb_acc: 0.5362 - class_acc: 0.9503 - val_loss: 3.5525 - val_bb_loss: 3419.4472 - val_class_loss: 0.1331 - val_bb_acc: 0.5960 - val_class_acc: 0.9800
Out[60]:
<keras.callbacks.History at 0x7fb666146050>

In [61]:
model.optimizer.lr = 1e-5

In [62]:
model.fit(conv_feat, [trn_bbox, trn_labels], batch_size=batch_size, nb_epoch=10, 
             validation_data=(conv_val_feat, [val_bbox, val_labels]))


Train on 3277 samples, validate on 500 samples
Epoch 1/10
3277/3277 [==============================] - 1s - loss: 3.7350 - bb_loss: 3629.4665 - class_loss: 0.1055 - bb_acc: 0.5795 - class_acc: 0.9716 - val_loss: 3.0999 - val_bb_loss: 2971.5778 - val_class_loss: 0.1283 - val_bb_acc: 0.6280 - val_class_acc: 0.9800
Epoch 2/10
3277/3277 [==============================] - 1s - loss: 2.9639 - bb_loss: 2878.7579 - class_loss: 0.0851 - bb_acc: 0.6128 - class_acc: 0.9768 - val_loss: 2.4759 - val_bb_loss: 2343.8384 - val_class_loss: 0.1321 - val_bb_acc: 0.6140 - val_class_acc: 0.9800
Epoch 3/10
3277/3277 [==============================] - 1s - loss: 2.0806 - bb_loss: 2034.5301 - class_loss: 0.0461 - bb_acc: 0.6536 - class_acc: 0.9884 - val_loss: 1.8290 - val_bb_loss: 1723.2244 - val_class_loss: 0.1057 - val_bb_acc: 0.6600 - val_class_acc: 0.9800
Epoch 4/10
3277/3277 [==============================] - 1s - loss: 1.3482 - bb_loss: 1292.2710 - class_loss: 0.0559 - bb_acc: 0.6945 - class_acc: 0.9869 - val_loss: 1.1265 - val_bb_loss: 1000.0838 - val_class_loss: 0.1264 - val_bb_acc: 0.7420 - val_class_acc: 0.9760
Epoch 5/10
3277/3277 [==============================] - 1s - loss: 0.7963 - bb_loss: 738.2009 - class_loss: 0.0581 - bb_acc: 0.7592 - class_acc: 0.9835 - val_loss: 0.6311 - val_bb_loss: 510.5506 - val_class_loss: 0.1205 - val_bb_acc: 0.8040 - val_class_acc: 0.9760
Epoch 6/10
3277/3277 [==============================] - 1s - loss: 0.4994 - bb_loss: 458.9412 - class_loss: 0.0404 - bb_acc: 0.8071 - class_acc: 0.9899 - val_loss: 0.4939 - val_bb_loss: 378.9873 - val_class_loss: 0.1149 - val_bb_acc: 0.8460 - val_class_acc: 0.9820
Epoch 7/10
3277/3277 [==============================] - 1s - loss: 0.3590 - bb_loss: 325.8812 - class_loss: 0.0331 - bb_acc: 0.8142 - class_acc: 0.9918 - val_loss: 0.4052 - val_bb_loss: 301.7754 - val_class_loss: 0.1035 - val_bb_acc: 0.8580 - val_class_acc: 0.9840
Epoch 8/10
3277/3277 [==============================] - 1s - loss: 0.2903 - bb_loss: 268.2826 - class_loss: 0.0220 - bb_acc: 0.8166 - class_acc: 0.9945 - val_loss: 0.3705 - val_bb_loss: 279.8890 - val_class_loss: 0.0907 - val_bb_acc: 0.8620 - val_class_acc: 0.9860
Epoch 9/10
3277/3277 [==============================] - 1s - loss: 0.2753 - bb_loss: 250.3531 - class_loss: 0.0250 - bb_acc: 0.8053 - class_acc: 0.9927 - val_loss: 0.3722 - val_bb_loss: 260.1041 - val_class_loss: 0.1121 - val_bb_acc: 0.8600 - val_class_acc: 0.9820
Epoch 10/10
3277/3277 [==============================] - 1s - loss: 0.2570 - bb_loss: 231.1665 - class_loss: 0.0259 - bb_acc: 0.7943 - class_acc: 0.9930 - val_loss: 0.3726 - val_bb_loss: 249.7608 - val_class_loss: 0.1228 - val_bb_acc: 0.8460 - val_class_acc: 0.9780
Out[62]:
<keras.callbacks.History at 0x7fb66f083990>

Excitingly, it turned out that the classification model is much improved by giving it this additional task. Let's see how well the bounding box model did by taking a look at its output.


In [63]:
pred = model.predict(conv_val_feat[0:10])

In [64]:
def show_bb_pred(i):
    bb = val_bbox[i]
    bb_pred = pred[0][i]
    plt.figure(figsize=(6,6))
    plot(val[i])
    ax=plt.gca()
    ax.add_patch(create_rect(bb_pred, 'yellow'))
    ax.add_patch(create_rect(bb))

The image shows that it can find fish that are tricky for us to see!


In [65]:
show_bb_pred(6)



In [66]:
model.evaluate(conv_val_feat, [val_bbox, val_labels])


480/500 [===========================>..] - ETA: 0s
Out[66]:
[0.37256381034851072,
 249.76081030273437,
 0.12280298530682922,
 0.84599999999999997,
 0.97799999952316286]

In [67]:
model.save_weights(path+'models/bn_anno.h5')

In [57]:
model.load_weights(path+'models/bn_anno.h5')

Larger size

Set up data

Let's see if we get better results if we use larger images. We'll use 640x360, since it's the same shape as the most common size we saw earlier (1280x720), without being too big.


In [68]:
trn = get_data(path+'train', (360,640))
val = get_data(path+'valid', (360,640))


Found 3277 images belonging to 8 classes.
Found 500 images belonging to 8 classes.

The image shows that things are much clearer at this size.


In [70]:
plot(trn[0])



In [71]:
test = get_data(path+'test', (360,640))


Found 1000 images belonging to 1 classes.

In [72]:
save_array(path+'results/trn_640.dat', trn)
save_array(path+'results/val_640.dat', val)

In [73]:
save_array(path+'results/test_640.dat', test)

In [6]:
trn = load_array(path+'results/trn_640.dat')
val = load_array(path+'results/val_640.dat')

We can now create our VGG model - we'll need to tell it we're not using the normal 224x224 images, which also means it won't include the fully connected layers (since they don't make sense for non-default sizes). We will also remove the last max pooling layer, since we don't want to throw away information yet.


In [74]:
vgg640 = Vgg16BN((360, 640)).model
vgg640.pop()
vgg640.input_shape, vgg640.output_shape
vgg640.compile(Adam(), 'categorical_crossentropy', metrics=['accuracy'])

We can now pre-compute the output of the convolutional part of VGG.


In [75]:
conv_val_feat = vgg640.predict(val, batch_size=32, verbose=1)
conv_trn_feat = vgg640.predict(trn, batch_size=32, verbose=1)


500/500 [==============================] - 57s    
3277/3277 [==============================] - 390s   

In [76]:
save_array(path+'results/conv_val_640.dat', conv_val_feat)
save_array(path+'results/conv_trn_640.dat', conv_trn_feat)

In [77]:
conv_test_feat = vgg640.predict(test, batch_size=32, verbose=1)


1000/1000 [==============================] - 115s   

In [83]:
save_array(path+'results/conv_test_640.dat', conv_test_feat)

In [10]:
conv_val_feat = load_array(path+'results/conv_val_640.dat')
conv_trn_feat = load_array(path+'results/conv_trn_640.dat')

In [868]:
conv_test_feat = load_array(path+'results/conv_test_640.dat')

Fully convolutional net (FCN)

Since we're using a larger input, the output of the final convolutional layer is also larger. So we probably don't want to put a dense layer there - that would be a lot of parameters! Instead, let's use a fully convolutional net (FCN); this also has the benefit that they tend to generalize well, and also seems like a good fit for our problem (since the fish are a small part of the image).


In [78]:
conv_layers,_ = split_at(vgg640, Convolution2D)

I'm not using any dropout, since I found I got better results without it.


In [79]:
nf=128; p=0.

In [80]:
def get_lrg_layers():
    return [
        BatchNormalization(axis=1, input_shape=conv_layers[-1].output_shape[1:]),
        Convolution2D(nf,3,3, activation='relu', border_mode='same'),
        BatchNormalization(axis=1),
        MaxPooling2D(),
        Convolution2D(nf,3,3, activation='relu', border_mode='same'),
        BatchNormalization(axis=1),
        MaxPooling2D(),
        Convolution2D(nf,3,3, activation='relu', border_mode='same'),
        BatchNormalization(axis=1),
        MaxPooling2D((1,2)),
        Convolution2D(8,3,3, border_mode='same'),
        Dropout(p),
        GlobalAveragePooling2D(),
        Activation('softmax')
    ]

In [81]:
lrg_model = Sequential(get_lrg_layers())

In [ ]:
lrg_model.summary()

In [84]:
lrg_model.compile(Adam(lr=0.001), loss='categorical_crossentropy', metrics=['accuracy'])

In [ ]:
lrg_model.fit(conv_trn_feat, trn_labels, batch_size=batch_size, nb_epoch=2, 
             validation_data=(conv_val_feat, val_labels))

In [86]:
lrg_model.optimizer.lr=1e-5

In [365]:
lrg_model.fit(conv_trn_feat, trn_labels, batch_size=batch_size, nb_epoch=6, 
             validation_data=(conv_val_feat, val_labels))


Train on 3277 samples, validate on 500 samples
Epoch 1/6
3277/3277 [==============================] - 6s - loss: 0.0417 - acc: 0.9896 - val_loss: 0.2282 - val_acc: 0.9440
Epoch 2/6
3277/3277 [==============================] - 6s - loss: 0.0346 - acc: 0.9921 - val_loss: 0.1377 - val_acc: 0.9520
Epoch 3/6
3277/3277 [==============================] - 6s - loss: 0.0090 - acc: 0.9979 - val_loss: 0.1374 - val_acc: 0.9620
Epoch 4/6
3277/3277 [==============================] - 6s - loss: 0.0097 - acc: 0.9988 - val_loss: 0.1127 - val_acc: 0.9680
Epoch 5/6
3277/3277 [==============================] - 6s - loss: 0.0041 - acc: 0.9994 - val_loss: 0.0969 - val_acc: 0.9740
Epoch 6/6
3277/3277 [==============================] - 6s - loss: 8.9966e-04 - acc: 1.0000 - val_loss: 0.0976 - val_acc: 0.9760
Out[365]:
<keras.callbacks.History at 0x7fb564eadf90>

When I submitted the results of this model to Kaggle, I got the best single model results of any shown here (ranked 22nd on the leaderboard as at Dec-6-2016.)


In [366]:
lrg_model.save_weights(path+'models/lrg_nmp.h5')

In [870]:
lrg_model.load_weights(path+'models/lrg_nmp.h5')

In [871]:
lrg_model.evaluate(conv_val_feat, val_labels)


500/500 [==============================] - 0s     
Out[871]:
[0.097560357421636587, 0.97599999999999998]

Another benefit of this kind of model is that the last convolutional layer has to learn to classify each part of the image (since there's only an average pooling layer after). Let's create a function that grabs the output of this layer (which is the 4th-last layer of our model).


In [872]:
l = lrg_model.layers
conv_fn = K.function([l[0].input, K.learning_phase()], l[-4].output)

In [881]:
def get_cm(imp, label):
    conv = conv_fn([inp,0])[0, label]
    return scipy.misc.imresize(conv, (360,640), interp='nearest')

We have to add an extra dimension to our input since the CNN expects a 'batch' (even if it's just a batch of one).


In [882]:
inp = np.expand_dims(conv_val_feat[0], 0)
np.round(lrg_model.predict(inp)[0],2)


Out[882]:
array([ 0.82,  0.  ,  0.  ,  0.  ,  0.17,  0.  ,  0.  ,  0.  ], dtype=float32)

In [883]:
plt.imshow(to_plot(val[0]))


Out[883]:
<matplotlib.image.AxesImage at 0x7faba62ae650>

In [885]:
cm = get_cm(inp, 0)

The heatmap shows that (at very low resolution) the model is finding the fish!


In [886]:
plt.imshow(cm, cmap="cool")


Out[886]:
<matplotlib.image.AxesImage at 0x7faba61f8210>

All convolutional net heatmap

To create a higher resolution heatmap, we'll remove all the max pooling layers, and repeat the previous steps.


In [14]:
def get_lrg_layers():
    return [
        BatchNormalization(axis=1, input_shape=conv_layers[-1].output_shape[1:]),
        Convolution2D(nf,3,3, activation='relu', border_mode='same'),
        BatchNormalization(axis=1),
        Convolution2D(nf,3,3, activation='relu', border_mode='same'),
        BatchNormalization(axis=1),
        Convolution2D(nf,3,3, activation='relu', border_mode='same'),
        BatchNormalization(axis=1),
        Convolution2D(8,3,3, border_mode='same'),
        GlobalAveragePooling2D(),
        Activation('softmax')
    ]

In [17]:
lrg_model = Sequential(get_lrg_layers())

In [18]:
lrg_model.summary()


____________________________________________________________________________________________________
Layer (type)                     Output Shape          Param #     Connected to                     
====================================================================================================
batchnormalization_2 (BatchNorma (None, 512, 22, 40)   1024        batchnormalization_input_1[0][0] 
____________________________________________________________________________________________________
convolution2d_14 (Convolution2D) (None, 128, 22, 40)   589952      batchnormalization_2[0][0]       
____________________________________________________________________________________________________
batchnormalization_3 (BatchNorma (None, 128, 22, 40)   256         convolution2d_14[0][0]           
____________________________________________________________________________________________________
convolution2d_15 (Convolution2D) (None, 128, 22, 40)   147584      batchnormalization_3[0][0]       
____________________________________________________________________________________________________
batchnormalization_4 (BatchNorma (None, 128, 22, 40)   256         convolution2d_15[0][0]           
____________________________________________________________________________________________________
convolution2d_16 (Convolution2D) (None, 128, 22, 40)   147584      batchnormalization_4[0][0]       
____________________________________________________________________________________________________
batchnormalization_5 (BatchNorma (None, 128, 22, 40)   256         convolution2d_16[0][0]           
____________________________________________________________________________________________________
convolution2d_17 (Convolution2D) (None, 8, 22, 40)     9224        batchnormalization_5[0][0]       
____________________________________________________________________________________________________
globalaveragepooling2d_1 (Global (None, 8)             0           convolution2d_17[0][0]           
____________________________________________________________________________________________________
activation_1 (Activation)        (None, 8)             0           globalaveragepooling2d_1[0][0]   
====================================================================================================
Total params: 896136
____________________________________________________________________________________________________

In [19]:
lrg_model.compile(Adam(lr=0.001), loss='categorical_crossentropy', metrics=['accuracy'])

In [891]:
lrg_model.fit(conv_trn_feat, trn_labels, batch_size=batch_size, nb_epoch=2, 
             validation_data=(conv_val_feat, val_labels))


Train on 3277 samples, validate on 500 samples
Epoch 1/2
3277/3277 [==============================] - 11s - loss: 0.9377 - acc: 0.7128 - val_loss: 2.7022 - val_acc: 0.6260
Epoch 2/2
3277/3277 [==============================] - 10s - loss: 0.2603 - acc: 0.9271 - val_loss: 0.4385 - val_acc: 0.9080
Out[891]:
<keras.callbacks.History at 0x7faba24a3b90>

In [892]:
lrg_model.optimizer.lr=1e-5

In [893]:
lrg_model.fit(conv_trn_feat, trn_labels, batch_size=batch_size, nb_epoch=6, 
             validation_data=(conv_val_feat, val_labels))


Train on 3277 samples, validate on 500 samples
Epoch 1/6
3277/3277 [==============================] - 11s - loss: 0.1027 - acc: 0.9747 - val_loss: 0.3641 - val_acc: 0.9060
Epoch 2/6
3277/3277 [==============================] - 10s - loss: 0.0498 - acc: 0.9844 - val_loss: 0.2743 - val_acc: 0.9200
Epoch 3/6
3277/3277 [==============================] - 10s - loss: 0.0359 - acc: 0.9918 - val_loss: 0.2262 - val_acc: 0.9520
Epoch 4/6
3277/3277 [==============================] - 11s - loss: 0.0339 - acc: 0.9912 - val_loss: 0.1877 - val_acc: 0.9540
Epoch 5/6
3277/3277 [==============================] - 10s - loss: 0.0242 - acc: 0.9945 - val_loss: 0.2320 - val_acc: 0.9460
Epoch 6/6
3277/3277 [==============================] - 10s - loss: 0.0211 - acc: 0.9930 - val_loss: 0.1813 - val_acc: 0.9520
Out[893]:
<keras.callbacks.History at 0x7faba24a8450>

In [894]:
lrg_model.save_weights(path+'models/lrg_0mp.h5')

In [20]:
lrg_model.load_weights(path+'models/lrg_0mp.h5')

Create heatmap


In [21]:
l = lrg_model.layers
conv_fn = K.function([l[0].input, K.learning_phase()], l[-3].output)

In [22]:
def get_cm2(imp, label):
    conv = conv_fn([inp,0])[0, label]
    return scipy.misc.imresize(conv, (360,640))

In [23]:
inp = np.expand_dims(conv_val_feat[0], 0)

In [900]:
plt.imshow(to_plot(val[0]))


Out[900]:
<matplotlib.image.AxesImage at 0x7faba0f47390>

In [912]:
cm = get_cm2(inp, 0)

In [24]:
cm = get_cm2(inp, 4)

In [913]:
plt.imshow(cm, cmap="cool")


Out[913]:
<matplotlib.image.AxesImage at 0x7faba09bd350>

In [903]:
plt.figure(figsize=(10,10))
plot(val[0])
plt.imshow(cm, cmap="cool", alpha=0.5)


Out[903]:
<matplotlib.image.AxesImage at 0x7faba24a3c50>

Inception mini-net

Here's an example of how to create and use "inception blocks" - as you see, they use multiple different convolution filter sizes and concatenate the results together. We'll talk more about these next year.


In [198]:
def conv2d_bn(x, nb_filter, nb_row, nb_col, subsample=(1, 1)):
    x = Convolution2D(nb_filter, nb_row, nb_col,
                      subsample=subsample, activation='relu', border_mode='same')(x)
    return BatchNormalization(axis=1)(x)

In [208]:
def incep_block(x):
    branch1x1 = conv2d_bn(x, 32, 1, 1, subsample=(2, 2))
    branch5x5 = conv2d_bn(x, 24, 1, 1)
    branch5x5 = conv2d_bn(branch5x5, 32, 5, 5, subsample=(2, 2))

    branch3x3dbl = conv2d_bn(x, 32, 1, 1)
    branch3x3dbl = conv2d_bn(branch3x3dbl, 48, 3, 3)
    branch3x3dbl = conv2d_bn(branch3x3dbl, 48, 3, 3, subsample=(2, 2))

    branch_pool = AveragePooling2D(
        (3, 3), strides=(2, 2), border_mode='same')(x)
    branch_pool = conv2d_bn(branch_pool, 16, 1, 1)
    return merge([branch1x1, branch5x5, branch3x3dbl, branch_pool],
              mode='concat', concat_axis=1)

In [271]:
inp = Input(vgg640.layers[-1].output_shape[1:]) 
x = BatchNormalization(axis=1)(inp)
x = incep_block(x)
x = incep_block(x)
x = incep_block(x)
x = Dropout(0.75)(x)
x = Convolution2D(8,3,3, border_mode='same')(x)
x = GlobalAveragePooling2D()(x)
outp = Activation('softmax')(x)

In [272]:
lrg_model = Model([inp], outp)

In [273]:
lrg_model.compile(Adam(lr=0.001), loss='categorical_crossentropy', metrics=['accuracy'])

In [274]:
lrg_model.fit(conv_trn_feat, trn_labels, batch_size=batch_size, nb_epoch=2, 
             validation_data=(conv_val_feat, val_labels))


Train on 3277 samples, validate on 500 samples
Epoch 1/2
3277/3277 [==============================] - 6s - loss: 1.3251 - acc: 0.5536 - val_loss: 1.4769 - val_acc: 0.5080
Epoch 2/2
3277/3277 [==============================] - 6s - loss: 0.4601 - acc: 0.8691 - val_loss: 0.9860 - val_acc: 0.7460
Out[274]:
<keras.callbacks.History at 0x7fb61d3f30d0>

In [275]:
lrg_model.optimizer.lr=1e-5

In [277]:
lrg_model.fit(conv_trn_feat, trn_labels, batch_size=batch_size, nb_epoch=6, 
             validation_data=(conv_val_feat, val_labels))


Train on 3277 samples, validate on 500 samples
Epoch 1/6
3277/3277 [==============================] - 6s - loss: 0.0260 - acc: 0.9945 - val_loss: 0.2117 - val_acc: 0.9480
Epoch 2/6
3277/3277 [==============================] - 6s - loss: 0.0240 - acc: 0.9957 - val_loss: 0.3007 - val_acc: 0.9280
Epoch 3/6
3277/3277 [==============================] - 6s - loss: 0.0120 - acc: 0.9976 - val_loss: 0.2506 - val_acc: 0.9500
Epoch 4/6
3277/3277 [==============================] - 6s - loss: 0.0060 - acc: 0.9991 - val_loss: 0.2389 - val_acc: 0.9480
Epoch 5/6
3277/3277 [==============================] - 6s - loss: 0.0029 - acc: 1.0000 - val_loss: 0.2160 - val_acc: 0.9580
Epoch 6/6
3277/3277 [==============================] - 6s - loss: 0.0028 - acc: 0.9991 - val_loss: 0.2116 - val_acc: 0.9580
Out[277]:
<keras.callbacks.History at 0x7fb62b9ffe10>

In [262]:
lrg_model.fit(conv_trn_feat, trn_labels, batch_size=batch_size, nb_epoch=10, 
             validation_data=(conv_val_feat, val_labels))


Train on 3277 samples, validate on 500 samples
Epoch 1/10
3277/3277 [==============================] - 6s - loss: 0.0029 - acc: 1.0000 - val_loss: 0.1610 - val_acc: 0.9540
Epoch 2/10
3277/3277 [==============================] - 6s - loss: 0.0016 - acc: 1.0000 - val_loss: 0.1313 - val_acc: 0.9540
Epoch 3/10
3277/3277 [==============================] - 6s - loss: 0.0995 - acc: 0.9707 - val_loss: 0.4845 - val_acc: 0.8760
Epoch 4/10
3277/3277 [==============================] - 6s - loss: 0.1335 - acc: 0.9551 - val_loss: 0.3103 - val_acc: 0.9300
Epoch 5/10
3277/3277 [==============================] - 6s - loss: 0.0634 - acc: 0.9780 - val_loss: 0.2923 - val_acc: 0.9340
Epoch 6/10
3277/3277 [==============================] - 6s - loss: 0.0205 - acc: 0.9930 - val_loss: 0.2316 - val_acc: 0.9500
Epoch 7/10
3277/3277 [==============================] - 6s - loss: 0.0049 - acc: 0.9997 - val_loss: 0.2048 - val_acc: 0.9660
Epoch 8/10
3277/3277 [==============================] - 6s - loss: 0.0016 - acc: 1.0000 - val_loss: 0.1842 - val_acc: 0.9680
Epoch 9/10
3277/3277 [==============================] - 6s - loss: 0.0011 - acc: 1.0000 - val_loss: 0.1799 - val_acc: 0.9660
Epoch 10/10
3277/3277 [==============================] - 6s - loss: 7.4032e-04 - acc: 1.0000 - val_loss: 0.1740 - val_acc: 0.9640
Out[262]:
<keras.callbacks.History at 0x7fb654a67650>

In [110]:
lrg_model.save_weights(path+'models/lrg_nmp.h5')

In [153]:
lrg_model.load_weights(path+'models/lrg_nmp.h5')

Pseudo-labeling


In [210]:
preds = model.predict([conv_test_feat, test_sizes], batch_size=batch_size*2)

In [212]:
gen = image.ImageDataGenerator()

In [214]:
test_batches = gen.flow(conv_test_feat, preds, batch_size=16)

In [215]:
val_batches = gen.flow(conv_val_feat, val_labels, batch_size=4)

In [217]:
batches = gen.flow(conv_feat, trn_labels, batch_size=44)

In [292]:
mi = MixIterator([batches, test_batches, val_batches)

In [220]:
bn_model.fit_generator(mi, mi.N, nb_epoch=8, validation_data=(conv_val_feat, val_labels))


Epoch 1/8
4833/4777 [==============================] - 4s - loss: 0.2538 - acc: 0.9462 - val_loss: 0.1313 - val_acc: 0.9700
Epoch 2/8
 192/4777 [>.............................] - ETA: 2s - loss: 0.1972 - acc: 0.9635
/usr/local/lib/python2.7/dist-packages/keras/engine/training.py:1494: UserWarning: Epoch comprised more than `samples_per_epoch` samples, which might affect learning results. Set `samples_per_epoch` correctly to avoid this warning.
  warnings.warn('Epoch comprised more than '
4833/4777 [==============================] - 4s - loss: 0.2231 - acc: 0.9491 - val_loss: 0.0820 - val_acc: 0.9820
Epoch 3/8
4833/4777 [==============================] - 3s - loss: 0.1860 - acc: 0.9545 - val_loss: 0.0580 - val_acc: 0.9840
Epoch 4/8
4833/4777 [==============================] - 3s - loss: 0.1559 - acc: 0.9663 - val_loss: 0.0521 - val_acc: 0.9840
Epoch 5/8
4825/4777 [==============================] - 3s - loss: 0.1366 - acc: 0.9693 - val_loss: 0.0422 - val_acc: 0.9840
Epoch 6/8
4833/4777 [==============================] - 3s - loss: 0.1303 - acc: 0.9704 - val_loss: 0.0195 - val_acc: 0.9940
Epoch 7/8
4833/4777 [==============================] - 3s - loss: 0.1283 - acc: 0.9708 - val_loss: 0.0133 - val_acc: 0.9940
Epoch 8/8
4833/4777 [==============================] - 4s - loss: 0.1199 - acc: 0.9752 - val_loss: 0.0247 - val_acc: 0.9900
Out[220]:
<keras.callbacks.History at 0x7f8a38b07e50>

Submit


In [821]:
def do_clip(arr, mx): return np.clip(arr, (1-mx)/7, mx)

In [829]:
lrg_model.evaluate(conv_val_feat, val_labels, batch_size*2)


500/500 [==============================] - 0s     
Out[829]:
[0.11417267167568207, 0.97199999332427978]

In [851]:
preds = model.predict(conv_test_feat, batch_size=batch_size)

In [852]:
preds = preds[1]

In [25]:
test = load_array(path+'results/test_640.dat')

In [5]:
test = load_array(path+'results/test.dat')

In [26]:
preds = conv_model.predict(test, batch_size=32)

In [853]:
subm = do_clip(preds,0.82)

In [854]:
subm_name = path+'results/subm_bb.gz'

In [855]:
# classes = sorted(batches.class_indices, key=batches.class_indices.get)
classes = ['ALB', 'BET', 'DOL', 'LAG', 'NoF', 'OTHER', 'SHARK', 'YFT']

In [856]:
submission = pd.DataFrame(subm, columns=classes)
submission.insert(0, 'image', raw_test_filenames)
submission.head()


Out[856]:
image ALB BET DOL LAG NoF OTHER SHARK YFT
0 img_00005.jpg 0.025714 0.025714 0.025714 0.025714 0.820000 0.025714 0.025714 0.025714
1 img_00007.jpg 0.820000 0.025714 0.025714 0.025714 0.025714 0.025714 0.025714 0.025714
2 img_00009.jpg 0.820000 0.025714 0.025714 0.025714 0.025714 0.025714 0.025714 0.025714
3 img_00018.jpg 0.457916 0.025714 0.025714 0.025714 0.025714 0.539635 0.025714 0.025714
4 img_00027.jpg 0.820000 0.025714 0.025714 0.025714 0.025714 0.025714 0.025714 0.102664

In [857]:
submission.to_csv(subm_name, index=False, compression='gzip')

In [858]:
FileLink(subm_name)





In [ ]: