有tensorflow1.12可以用的计算感知损失的代码(生成图片,风格图片,内容图片)吗
时间: 2024-02-11 10:04:42 浏览: 110
tensorflow 自定义损失函数示例代码
当然可以,以下是计算感知损失的代码示例:
```python
import tensorflow as tf
import numpy as np
import cv2
def gram_matrix(input_tensor):
# 将特征图展平为2D矩阵
input_shape = tf.shape(input_tensor)
h = input_shape[1]
w = input_shape[2]
c = input_shape[3]
features = tf.reshape(input_tensor, [-1, h * w, c])
# 计算Gram矩阵
gram = tf.matmul(features, features, transpose_a=True)
return gram
def compute_style_loss(style_features, generated_features):
# 计算风格损失
style_loss = 0.
for style_feature, generated_feature in zip(style_features, generated_features):
style_gram = gram_matrix(style_feature)
generated_gram = gram_matrix(generated_feature)
style_loss += tf.reduce_mean(tf.square(style_gram - generated_gram)) / (4. * tf.cast(tf.size(generated_feature), tf.float32) ** 2)
return style_loss
def compute_content_loss(content_features, generated_features):
# 计算内容损失
content_loss = tf.reduce_mean(tf.square(content_features - generated_features))
return content_loss
def compute_perceptual_loss(style_image_path, content_image_path, generated_image_path):
# 加载风格图片、内容图片和生成图片
style_image = tf.keras.preprocessing.image.load_img(style_image_path, target_size=(256, 256))
content_image = tf.keras.preprocessing.image.load_img(content_image_path, target_size=(256, 256))
generated_image = tf.keras.preprocessing.image.load_img(generated_image_path, target_size=(256, 256))
# 将图片转换为numpy数组,并扩展维度以匹配模型的输入形状
style_image_array = np.expand_dims(tf.keras.preprocessing.image.img_to_array(style_image), axis=0)
content_image_array = np.expand_dims(tf.keras.preprocessing.image.img_to_array(content_image), axis=0)
generated_image_array = np.expand_dims(tf.keras.preprocessing.image.img_to_array(generated_image), axis=0)
# 对图片进行归一化处理
style_image_array = tf.keras.applications.vgg19.preprocess_input(style_image_array)
content_image_array = tf.keras.applications.vgg19.preprocess_input(content_image_array)
generated_image_array = tf.keras.applications.vgg19.preprocess_input(generated_image_array)
# 加载VGG19模型,并指定需要输出的层
vgg19 = tf.keras.applications.VGG19(include_top=False, weights='imagenet')
style_layers = ['block1_conv1', 'block2_conv1', 'block3_conv1', 'block4_conv1']
content_layers = ['block5_conv2']
# 构建模型,用于获取风格图片、内容图片和生成图片在指定层的特征
outputs = [vgg19.get_layer(name).output for name in style_layers + content_layers]
model = tf.keras.models.Model(inputs=vgg19.inputs, outputs=outputs)
# 计算风格图片、内容图片和生成图片在指定层的特征
style_features = model(style_image_array)[:len(style_layers)]
content_features = model(content_image_array)[len(style_layers):]
generated_features = model(generated_image_array)[len(style_layers):]
# 计算损失
style_loss = compute_style_loss(style_features, generated_features[:len(style_layers)])
content_loss = compute_content_loss(content_features, generated_features[len(style_layers):])
perceptual_loss = style_loss + content_loss
return perceptual_loss.numpy()
```
其中,`style_image_path`、`content_image_path`和`generated_image_path`分别表示风格图片、内容图片和生成图片的路径。需要注意的是,该代码使用VGG19模型来计算特征,并计算风格损失和内容损失,最终得到感知损失(即风格损失和内容损失之和)。
阅读全文