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A dataset and open-ended challenge for music recommendation research
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AI Blitz 5 β‘
Solution to TXTOCR
Almost 4 years agoFirst, I did some preprocessing to get binary (black and white) images. For that I first converted images to grayscale using rgb2gray and then to binary using imbinarize in MATLAB.
Now that I have binary images, I just tweaked the following code to train my data:
The code is provided below. I also did some post-processing. It actually improved the result a lot. I took the predictions and calculated the Levenshtein distance between the predicted word and each word in the dictionary of the words in training set, and the replaced the predicted word with the word in the dictionary of the words in the training set with whom it has the smallest Levenshtein distance.
Code for postprocessing:
import pandas as pd
from Levenshtein import distance as levenshtein_distance
import numpy as np
xx=pd.read_csv(βpredictions.csvβ)
ocr_list=[]
for i in range(10000):
etwas=xx.iloc[i][βlabelβ]
etwas=str(etwas)
metwas=etwas.split()
ocr_list.append(metwas)
yy=pd.read_csv(βtrain.csvβ)
list2=[]
for i in range(40000):
z=yy.iloc[i][βlabelβ]
z=str(z)
zlist=z.split()
for j in zlist:
list2.append(j)
def distancer(x,y):
index=0
mymin=levenshtein_distance(x,y[0])
for i in range(len(y)):
m=levenshtein_distance(y[i],x)
if m < mymin:
mymin=m
index=i
return y[index]
for i in range(len(ocr_list)):
if len(ocr_list[i])==1:
ocr_list[i][0]=distancer(ocr_list[i][0],list2)
if len(ocr_list[i])==2:
ocr_list[i][0]=distancer(ocr_list[i][0],list2)
ocr_list[i][1]=distancer(ocr_list[i][1],list2)
for i in range(10000):
if xx.iloc[i][βlabelβ]==βnanβ:
xx.at[i, βlabelβ]=""
else:
xx.at[i,βlabelβ]=" ".join(ocr_list[i])
xx.to_csv(βsubmission.csvβ, index=False)
Training code: From https://github.com/keras-team/keras-io/blob/master/examples/vision/captcha_ocr.py
#!/usr/bin/env python
coding: utf-8
In[28]:
import pandas as pd
import numpy as np
import matplotlib.pyplot as plt
from pathlib import Path
from collections import Counter
import tensorflow as tf
from tensorflow import keras
from tensorflow.keras import layers
import os
import re
def atoi(text):
return int(text) if text.isdigit() else text
def natural_keys(text):
return [ atoiΒ© for c in re.split(β(\d+)β,text) ]
In[29]:
train_data_dir=os.listdir("./bwtrain")
train_data_dir.sort(key=natural_keys)
x_train=train_data_dir
In[30]:
y_train=pd.read_csv(βtrain.csvβ)[βlabelβ].tolist()
for i in range(len(y_train)):
y_train[i]=str(y_train[i])
characters=set(βabcdefghijklmnopqrstuvwxyzβ)
characters.add(β β)
characters.add(β.β)
In[31]:
val_data_dir=os.listdir("./bwval")
val_data_dir.sort(key=natural_keys)
x_val=val_data_dir
In[32]:
y_val=pd.read_csv(βval.csvβ)[βlabelβ].tolist()
for i in range(len(y_val)):
y_val[i]=str(y_val[i])
In[33]:
batch_size = 1
img_width = 256
img_height=256
downsample_factor = 4
max_length = max([len(label) for label in y_train])
In[34]:
for i in range(len(x_train)):
x_train[i]=f"./bwtrain/{i}.png"
for i in range(len(x_val)):
x_val[i]=f"./bwval/{i}.png"
x_train, y_train, x_val, y_val= np.array(x_train), np.array(y_train), np.array(x_val), np.array(y_val)
In[35]:
Mapping characters to integers
char_to_num = layers.experimental.preprocessing.StringLookup(
vocabulary=list(characters), num_oov_indices=0, mask_token=None
)
Mapping integers back to original characters
num_to_char = layers.experimental.preprocessing.StringLookup(
vocabulary=char_to_num.get_vocabulary(), mask_token=None, invert=True
)
In[36]:
def encode_single_sample(img_path,label):
# 1. Read image
img = tf.io.read_file(img_path)
# 2. Decode and convert to grayscale
img = tf.io.decode_png(img, channels=0)
# 3. Convert to float32 in [0, 1] range
img = tf.image.convert_image_dtype(img, tf.float32)
# 4. Resize to the desired size
img = tf.image.resize(img, [img_height, img_width])
# 5. Transpose the image because we want the time
# dimension to correspond to the width of the image.
img = tf.transpose(img, perm=[1, 0, 2])
# 6. Map the characters in label to numbers
label = char_to_num(tf.strings.unicode_split(label, input_encoding=βUTF-8β))
# 7. Return a dict as our model is expecting two inputs
return {βimageβ: img, βlabelβ: label}
In[37]:
train_dataset = tf.data.Dataset.from_tensor_slices((x_train, y_train))
train_dataset = (
train_dataset.map(
encode_single_sample, num_parallel_calls=tf.data.experimental.AUTOTUNE
)
.batch(batch_size)
.prefetch(buffer_size=tf.data.experimental.AUTOTUNE)
)
validation_dataset = tf.data.Dataset.from_tensor_slices((x_val, y_val))
validation_dataset = (
validation_dataset.map(
encode_single_sample, num_parallel_calls=tf.data.experimental.AUTOTUNE
)
.batch(batch_size)
.prefetch(buffer_size=tf.data.experimental.AUTOTUNE)
)
#print(list(train_dataset.as_numpy_iterator()))
In[38]:
class CTCLayer(layers.Layer):
def init(self, name=None):
super().init(name=name)
self.loss_fn = keras.backend.ctc_batch_cost
def call(self, y_true, y_pred):
# Compute the training-time loss value and add it
# to the layer using `self.add_loss()`.
batch_len = tf.cast(tf.shape(y_true)[0], dtype="int64")
input_length = tf.cast(tf.shape(y_pred)[1], dtype="int64")
label_length = tf.cast(tf.shape(y_true)[1], dtype="int64")
input_length = input_length * tf.ones(shape=(batch_len, 1), dtype="int64")
label_length = label_length * tf.ones(shape=(batch_len, 1), dtype="int64")
loss = self.loss_fn(y_true, y_pred, input_length, label_length)
self.add_loss(loss)
# At test time, just return the computed predictions
return y_pred
In[39]:
def build_model():
# Inputs to the model
input_img = layers.Input(
shape=(img_width, img_height, 1), name=βimageβ, dtype=βfloat32β
)
labels = layers.Input(name=βlabelβ, shape=(None,), dtype=βfloat32β)
# First conv block
x = layers.Conv2D(
32,
(3, 3),
activation="relu",
kernel_initializer="he_normal",
padding="same",
name="Conv1",
)(input_img)
x = layers.MaxPooling2D((2, 2), name="pool1")(x)
# Second conv block
x = layers.Conv2D(
64,
(3, 3),
activation="relu",
kernel_initializer="he_normal",
padding="same",
name="Conv2",
)(x)
x = layers.MaxPooling2D((2, 2), name="pool2")(x)
# We have used two max pool with pool size and strides 2.
# Hence, downsampled feature maps are 4x smaller. The number of
# filters in the last layer is 64. Reshape accordingly before
# passing the output to the RNN part of the model
new_shape = ((img_width // 4), (img_height // 4) * 64)
x = layers.Reshape(target_shape=new_shape, name="reshape")(x)
x = layers.Dense(64, activation="relu", name="dense1")(x)
x = layers.Dropout(0.2)(x)
# RNNs
x = layers.Bidirectional(layers.LSTM(128, return_sequences=True, dropout=0.25))(x)
x = layers.Bidirectional(layers.LSTM(64, return_sequences=True, dropout=0.25))(x)
# Output layer
x = layers.Dense(len(characters) + 1, activation="softmax", name="dense2")(x)
# Add CTC layer for calculating CTC loss at each step
output = CTCLayer(name="ctc_loss")(labels, x)
# Define the model
model = keras.models.Model(
inputs=[input_img, labels], outputs=output, name="ocr_model_v1"
)
# Optimizer
opt = keras.optimizers.Adam()
# Compile the model and return
model.compile(optimizer=opt)
return model
In[ ]:
Get the model
#model = build_model()
model=keras.models.load_model(β./OCRMβ)
model.summary()
ββ"
Training
ββ"
epochs = 100
early_stopping_patience = 10
Add early stopping
early_stopping = keras.callbacks.EarlyStopping(
monitor=βval_lossβ, patience=early_stopping_patience, restore_best_weights=True
)
checkpoint_filepath = β./checkpointβ
model_checkpoint_callback = tf.keras.callbacks.ModelCheckpoint(
filepath=checkpoint_filepath,
monitor=βval_lossβ,
mode=βmaxβ,
save_best_only=True)
Train the model
history = model.fit(
train_dataset,
validation_data=validation_dataset,
epochs=epochs,
callbacks=[early_stopping,model_checkpoint_callback],
)
In[ ]:
prediction_model = keras.models.Model(
model.get_layer(name=βimageβ).input, model.get_layer(name=βdense2β).output
)
prediction_model.summary()
In[ ]:
A utility function to decode the output of the network
def decode_batch_predictions(pred):
input_len = np.ones(pred.shape[0]) * pred.shape[1]
# Use greedy search. For complex tasks, you can use beam search
results = keras.backend.ctc_decode(pred, input_length=input_len, greedy=True)[0][0][
:, :max_length
]
# Iterate over the results and get back the text
output_text = []
for res in results:
res = tf.strings.reduce_join(num_to_char(res)).numpy().decode(βutf-8β)
output_text.append(res)
return output_text
In[ ]:
test_data_dir=os.listdir("./bwtest")
test_data_dir.sort(key=natural_keys)
x_test=test_data_dir
y_test=y_train[0:10000]
for i in range(len(x_test)):
x_test[i]=f"./bwtest/{i}.png"
x_test=np.array(x_test)
y_test=np.array(y_test)
test_dataset = tf.data.Dataset.from_tensor_slices((x_test, y_test))
test_dataset = (
test_dataset.map(
encode_single_sample, num_parallel_calls=tf.data.experimental.AUTOTUNE
)
.batch(batch_size)
.prefetch(buffer_size=tf.data.experimental.AUTOTUNE)
)
my_list=[]
for batch in test_dataset:
batch_images = batch[βimageβ]
batch_labels = batch[βlabelβ]
preds = prediction_model.predict(batch_images)
pred_texts = decode_batch_predictions(preds)
my_list.append(pred_texts)
print(pred_texts)
with open(βpredictions.txtβ, βaβ) as f:
for item in my_list:
f.write("%s\n" % item)
In[ ]:
#m=os.listdir("./bwtrain_copy")
#m.sort(key=natural_keys)
In[ ]:
for batch in validation_dataset.take(1):
batch_images = batch[βimageβ]
batch_labels = batch[βlabelβ]
preds = prediction_model.predict(batch_images)
pred_texts = decode_batch_predictions(preds)
orig_texts = []
for label in batch_labels:
label = tf.strings.reduce_join(num_to_char(label)).numpy().decode("utf-8")
orig_texts.append(label)
_, ax = plt.subplots(4, 4, figsize=(15, 5))
for i in range(len(pred_texts)):
img = (batch_images[i, :, :, 0] * 255).numpy().astype(np.uint8)
img = img.T
title = f"Prediction: {pred_texts[i]}"
ax[i // 4, i % 4].imshow(img, cmap="gray")
ax[i // 4, i % 4].set_title(title)
ax[i // 4, i % 4].axis("off")
plt.show()
Solution to TIMSER
Almost 4 years agoIt is just simple linear regression with log transformation (Here I did log log transformation but log transformation alone gives pretty much the same results). More importantly, I ignored training data completely as it is too much in the past and just introduces noise (most of the training data are from before the 2007 crisis, so it is to be expected that it is not very informative post-2007). I used only validation data for regression.
import pandas as pd
import numpy as np
import matplotlib.pyplot as plt
from sklearn.linear_model import LinearRegression
In[68]:
val_df=pd.read_csv(βval.csvβ)
subm=pd.read_csv(βsample_submission_copy.csvβ)
In[69]:
X=np.arange(len(val_df)).reshape(-1,1)
Y=val_df.iloc[:,1].values.reshape(-1,1)
Y=np.log(Y)
Y=np.log(Y)
In[70]:
linear_regressor=LinearRegression(normalize=True)
In[71]:
linear_regressor.fit(X,Y)
In[72]:
test_X=np.arange(len(val_df),len(val_df)+1904).reshape(-1,1)
In[73]:
Y_pred=linear_regressor.predict(test_X)
In[74]:
plt.scatter(X,Y)
plt.plot(test_X, Y_pred, color=βredβ)
plt.show()
In[75]:
Y_pred= np.exp(np.exp(Y_pred))
In[76]:
Y_pred=pd.DataFrame(data=Y_pred, index=np.array(range(1904)), columns=np.array(range(1)))
In[77]:
subm[βvalueβ]=Y_pred
In[78]:
subma=subm.to_csv(βsubmission.csvβ)
Solutions to SOUSEN and IMGCOL (and OBJDE)
Almost 4 years agoUnfortunately submitting just β2β to SOUSEN produces decent results, as everyone knows at this point. So I did that. Also submitting baseline to OBJDE gave a decent ranking
For IMGCOL, DeOldify produces very good results. Link:
The script I used to run DeOldify:
from deoldify import device
from deoldify.device_id import DeviceId
#choices: CPU, GPU0β¦GPU7
device.set(device=DeviceId.GPU0)
from deoldify.visualize import *
plt.style.use(βdark_backgroundβ)
torch.backends.cudnn.benchmark=True
import warnings
warnings.filterwarnings(βignoreβ, category=UserWarning, message=".?Your .? set is empty.*?")
colorizer = get_image_colorizer(artistic=True)
render_factor=45
m=os.listdir(β./test_back_white_imagesβ)
for file in m:
source_path = f"./test_back_white_images/{file}"
result_path = f"./test_color_images/{file}"
source_url=None
if source_url is not None:
result_path = colorizer.plot_transformed_image_from_url(url=source_url, path=source_path, render_factor=render_factor, compare=True)
else:
result_path = colorizer.plot_transformed_image(path=source_path, render_factor=render_factor, compare=True)
plt.close(βallβ)