PhilHolst's picture
Duplicate from MandyH/image-captioning-v4
36f23eb
# Databricks notebook source
import tensorflow as tf
import matplotlib.pyplot as plt
import numpy as np
from PIL import Image
#from turtle import width
import streamlit as st
# COMMAND ----------
def load_image_initial(image_file):
img = Image.open(image_file)
return img
#streamlit
header = st.container()
image = st.container()
caption = st.container()
with header:
st.title('Image Captioning')
st.text('Generate captions for your images!')
with image:
# st.markdown("**upload your image here:**")
image_file = st.file_uploader("upload your image here:", type = ["png", "jpg", 'jpeg'])
if image_file is not None:
#st.write(type(image_file))
# st.write(dir(image_file))
# file_details = {"filename": image_file.name, "filetype":image_file.type, "filesize":image_file.size}
# st.write(file_details)
st.image(load_image_initial(image_file), width=299)
################################model 14
num_predictions = 3
feature_extraction_model = 'ResNet50'
tokenizer_path = 'tokenizer.pkl'
# checkpoint_path = "/dbfs/FileStore/shared_uploads/mhajiza@gap.com/computer_vision/models/image_captioning_tf_14/ckpt-10"
# checkpoint_path = "/dbfs/FileStore/shared_uploads/mhajiza@gap.com/computer_vision/models/image_captioning_tf_14/manually_saved_model-11"
# checkpoint_path = "/Users/mhajiza/Documents/Computer_Vison/Image_captioning/image_captioning_tf_model/ckpt-10"
checkpoint_path = "ckpt-10"
weights= "checkpoint"
# checkpoint_path = "/Users/mhajiza/Documents/Computer_Vison/Image_captioning/image_captioning_tf_model/manually_saved_model-11"
# COMMAND ----------
def load_image(image_file):
img = Image.open(image_file).convert('RGB')
img = tf.keras.preprocessing.image.img_to_array(img)
img = tf.keras.layers.Resizing(299, 299)(img)
if feature_extraction_model == 'InceptionV3':
img = tf.keras.applications.inception_v3.preprocess_input(img)
if (feature_extraction_model == 'ResNet50') or (feature_extraction_model == 'ResNet101') or (feature_extraction_model == 'ResNet152'):
img = tf.keras.applications.resnet.preprocess_input(img)
return img, image_file
# COMMAND ----------
#Initialize ResNet and load the pretrained Imagenet weights
if feature_extraction_model == 'ResNet152':
image_model = tf.keras.applications.ResNet152(include_top=False, weights=weights)
new_input = image_model.input
hidden_layer = image_model.layers[-1].output
image_features_extract_model = tf.keras.Model(new_input, hidden_layer)
if feature_extraction_model == 'ResNet50':
image_model = tf.keras.applications.ResNet50(include_top=False, weights=weights)
new_input = image_model.input
hidden_layer = image_model.layers[-1].output
image_features_extract_model = tf.keras.Model(new_input, hidden_layer)
if feature_extraction_model == 'ResNet101':
image_model = tf.keras.applications.ResNet101(include_top=False, weights=weights)
new_input = image_model.input
hidden_layer = image_model.layers[-1].output
image_features_extract_model = tf.keras.Model(new_input, hidden_layer)
if feature_extraction_model == 'InceptionV3':
image_model = tf.keras.applications.InceptionV3(include_top=False, weights=weights)
new_input = image_model.input
hidden_layer = image_model.layers[-1].output
image_features_extract_model = tf.keras.Model(new_input, hidden_layer)
# COMMAND ----------
def standardize(inputs):
inputs = tf.strings.lower(inputs)
return tf.strings.regex_replace(inputs, r"!\"#$%&\(\)\*\+.,-/:;=?@\[\\\]^_`{|}~", "")
import pickle
from tensorflow.keras.layers.experimental.preprocessing import TextVectorization
from_disk = pickle.load(open(tokenizer_path, "rb"))
tokenizer = TextVectorization.from_config(from_disk['config'])
tokenizer.adapt(["this is a test"])
tokenizer.set_weights(from_disk['weights'])
# COMMAND ----------
vocabulary_size = tokenizer.get_config()['max_tokens']
max_length = tokenizer.get_config()['output_sequence_length']
# COMMAND ----------
# Create mappings for words to indices and indices to words.
word_to_index = tf.keras.layers.StringLookup(mask_token="", vocabulary=tokenizer.get_vocabulary())
index_to_word = tf.keras.layers.StringLookup( mask_token="", vocabulary=tokenizer.get_vocabulary(), invert=True)
# COMMAND ----------
# max_length = 95 ##100
embedding_dim = 256
units = 512
# Shape of the vector extracted from InceptionV3 is (64, 2048)
# These two variables represent that vector shape
features_shape = 2048
attention_features_shape = 64
# COMMAND ----------
class BahdanauAttention(tf.keras.Model): #####Attention mechanism
def __init__(self, units):
super(BahdanauAttention, self).__init__()
self.W1 = tf.keras.layers.Dense(units)
self.W2 = tf.keras.layers.Dense(units)
self.V = tf.keras.layers.Dense(1)
def call(self, features, hidden):
# features(CNN_encoder output) shape == (batch_size, 64, embedding_dim) ######(batch_size, 64, 2048)
# hidden shape == (batch_size, hidden_size)
# hidden_with_time_axis shape == (batch_size, 1, hidden_size) ##### this is after expanding with axis =1
hidden_with_time_axis = tf.expand_dims(hidden, 1)
# attention_hidden_layer shape == (batch_size, 64, units)
attention_hidden_layer = (tf.nn.tanh(self.W1(features) +
self.W2(hidden_with_time_axis)))
# score shape == (batch_size, 64, 1)
# This gives you an unnormalized score for each image feature.
score = self.V(attention_hidden_layer)
# attention_weights shape == (batch_size, 64, 1)
attention_weights = tf.nn.softmax(score, axis=1)
# context_vector shape after sum == (batch_size, hidden_size)
context_vector = attention_weights * features
context_vector = tf.reduce_sum(context_vector, axis=1)
return context_vector, attention_weights
# COMMAND ----------
class CNN_Encoder(tf.keras.Model):
# Since you have already extracted the features and dumped it
# This encoder passes those features through a Fully connected layer
def __init__(self, embedding_dim):
super(CNN_Encoder, self).__init__()
# shape after fc == (batch_size, 64, embedding_dim)
self.fc = tf.keras.layers.Dense(embedding_dim)
def call(self, x):
x = self.fc(x)
x = tf.nn.relu(x)
return x
# COMMAND ----------
class RNN_Decoder(tf.keras.Model):
def __init__(self, embedding_dim, units, vocab_size):
super(RNN_Decoder, self).__init__()
self.units = units
self.embedding = tf.keras.layers.Embedding(vocab_size, embedding_dim)
self.gru = tf.keras.layers.GRU(self.units,
return_sequences=True,
return_state=True,
recurrent_initializer='glorot_uniform')
self.fc1 = tf.keras.layers.Dense(self.units)
self.fc2 = tf.keras.layers.Dense(vocab_size)
self.attention = BahdanauAttention(self.units)
def call(self, x, features, hidden):
# defining attention as a separate model
context_vector, attention_weights = self.attention(features, hidden)
# x shape after passing through embedding == (batch_size, 1, embedding_dim)
x = self.embedding(x)
# x shape after concatenation == (batch_size, 1, embedding_dim + hidden_size)
x = tf.concat([tf.expand_dims(context_vector, 1), x], axis=-1)
# passing the concatenated vector to the GRU
output, state = self.gru(x)
# shape == (batch_size, max_length, hidden_size)
x = self.fc1(output)
# x shape == (batch_size * max_length, hidden_size)
x = tf.reshape(x, (-1, x.shape[2]))
# output shape == (batch_size * max_length, vocab)
x = self.fc2(x)
return x, state, attention_weights
def reset_state(self, batch_size):
return tf.zeros((batch_size, self.units))
# COMMAND ----------
encoder = CNN_Encoder(embedding_dim)
decoder = RNN_Decoder(embedding_dim, units, tokenizer.vocabulary_size())
# COMMAND ----------
optimizer = tf.keras.optimizers.Adam()
loss_object = tf.keras.losses.SparseCategoricalCrossentropy(
from_logits=True, reduction='none')
def loss_function(real, pred):
mask = tf.math.logical_not(tf.math.equal(real, 0))
loss_ = loss_object(real, pred)
mask = tf.cast(mask, dtype=loss_.dtype)
loss_ *= mask
return tf.reduce_mean(loss_)
# COMMAND ----------
ckpt = tf.train.Checkpoint(encoder=encoder,
decoder=decoder,
optimizer=optimizer)
ckpt_manager = tf.train.CheckpointManager(ckpt, checkpoint_path, max_to_keep=2)
# ckpt.restore(ckpt_manager.latest_checkpoint)
# COMMAND ----------
ckpt.restore(checkpoint_path)
# COMMAND ----------
def evaluate(image):
# attention_plot = np.zeros((max_length, attention_features_shape))
attention_plot = np.zeros((max_length, 100))
hidden = decoder.reset_state(batch_size=1)
temp_input = tf.expand_dims(load_image(image)[0], 0)
img_tensor_val = image_features_extract_model(temp_input)
# print(img_tensor_val.shape)
img_tensor_val = tf.reshape(img_tensor_val, (img_tensor_val.shape[0],
-1,
img_tensor_val.shape[3]))
# print(img_tensor_val.shape)
features = encoder(img_tensor_val)
# print(features.shape)
dec_input = tf.expand_dims([word_to_index('<start>')], 0)
result = []
for i in range(max_length):
predictions, hidden, attention_weights = decoder(dec_input,
features,
hidden)
attention_plot[i] = tf.reshape(attention_weights, (-1, )).numpy()
predicted_id = tf.random.categorical(predictions, 1)[0][0].numpy()
predicted_word = tf.compat.as_text(index_to_word(predicted_id).numpy())
result.append(predicted_word)
if predicted_word == '<end>':
return result, attention_plot
dec_input = tf.expand_dims([predicted_id], 0)
attention_plot = attention_plot[:len(result), :]
return result, attention_plot
# COMMAND ----------
def plot_attention(image, result, attention_plot):
temp_image = np.array(Image.open(image))
fig = plt.figure(figsize=(30, 30))
len_result = len(result)
for i in range(len_result):
temp_att = np.resize(attention_plot[i], (8, 8))
grid_size = max(int(np.ceil(len_result/2)), 2)
ax = fig.add_subplot(grid_size, grid_size, i+1)
ax.set_title(result[i])
img = ax.imshow(temp_image)
ax.imshow(temp_att, cmap='gray', alpha=0.6, extent=img.get_extent())
plt.tight_layout()
plt.show()
# COMMAND ----------
if image_file is not None:
with caption:
st.header("generated captions by model:")
for i in range(1, num_predictions+1):
p = st.empty()
result, _ = evaluate(image_file)
pred = ' '.join(result)
p.write(f"**caption {i}**: {pred}")
# st.header("**caption**")
# st.text(pred)