使用keras做图像分割

偏执的太偏执、 2022-12-10 10:27 130阅读 0赞

先 看一下效果 ，虽然 算不上很好

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3pob3VfNDM4_size_16_color_FFFFFF_t_70][]

直接上代码:

import tensorflow as tf
    import matplotlib.pyplot as plt
    import  os
    import time
    import numpy as np
    import io
    import PIL
    from IPython.display import clear_output
    import cv2
    import sys
    sys.path.append("/opt/LIP/examples")
    from tensorflow_examples.models.pix2pix import pix2pix
    
    IMG_WIDTH = 128
    IMG_WIDTH = 128
    IM_PATH='/opt/LIP/images/'
    MS_PATH='/opt/LIP/masks/'
    OUTPUT_CHANNELS = 20
    EPOCHS = 20
    BATCH_SIZE=256
    
    def display(display_list):
        plt.figure(figsize=(15, 15))
        title = ['Input Image', 'True Mask', 'Predicted Mask']
        for i in range(len(display_list)):
            plt.subplot(1, len(display_list), i+1)
            plt.title(title[i])
            plt.imshow(tf.keras.preprocessing.image.array_to_img(display_list[i]))
            plt.axis('off')
        plt.show()
    
    
    def load_input(image_file):
        print(image_file)
        #print(str(image_file))
        img=tf.io.read_file(image_file)
        img=tf.image.decode_jpeg(img, channels=3)
        image=tf.image.resize(img, [IMG_WIDTH, IMG_WIDTH])
        image=(image / 127.5) - 1#normalizing the images to [-1, 1]
        #image=image /255.0
        #image=image.reshape()
        #image=tf.reshape(image,[1,IMG_WIDTH,IMG_WIDTH,3])
        return image
    def load_mask(image_file):
        img=tf.io.read_file(image_file)
        img=tf.image.decode_png(img, channels=1)
        image=tf.image.resize(img, [IMG_WIDTH, IMG_WIDTH])
        #image -= 1
        #image=image.reshape(1,IMG_WIDTH,IMG_WIDTH,3)
        #image=tf.reshape(image,[1,IMG_WIDTH,IMG_WIDTH,3])
        return image
    def load(image_file,mask_file):
        _in=load_input(image_file)
        _mask=load_mask(mask_file)
        return _in,_mask
    
    train_image_path = os.path.join(IM_PATH+'train/')
    train_mask_path = os.path.join(MS_PATH+'train/')
    train_images = os.listdir(train_image_path)
    train_masks = os.listdir(train_mask_path)
    train_images.sort()
    train_masks.sort()
    train_ls_images=[]
    train_ls_masks=[]
    for i in train_images:
        train_ls_images.append(IM_PATH+'train/'+i)
    for j in train_masks:
        train_ls_masks.append(MS_PATH+'train/'+j)
    train_images = tf.constant(train_ls_images)
    train_labels = tf.constant(train_ls_masks)
    train_data = tf.data.Dataset.from_tensor_slices((train_images, train_labels))
    train_data = train_data.map(load, num_parallel_calls=4)
    train_batched_data = train_data.batch(BATCH_SIZE)
    
    val_image_path = os.path.join(IM_PATH+'val/')
    val_mask_path = os.path.join(MS_PATH+'val/')
    val_images = os.listdir(val_image_path)
    val_masks = os.listdir(val_mask_path)
    val_images.sort()
    val_masks.sort()
    val_ls_images=[]
    val_ls_masks=[]
    for i in val_images:
        val_ls_images.append(IM_PATH+'val/'+i)
    for j in val_masks:
        val_ls_masks.append(MS_PATH+'val/'+j)
    val_images = tf.constant(val_ls_images)
    val_labels = tf.constant(val_ls_masks)
    val_data = tf.data.Dataset.from_tensor_slices((val_images, val_labels))
    val_data = val_data.map(load, num_parallel_calls=4)
    val_batched_data = val_data.batch(BATCH_SIZE)
    
    
    base_model = tf.keras.applications.MobileNetV2(input_shape=[128, 128, 3], include_top=False)
    # Use the activations of these layers
    layer_names = [
        'block_1_expand_relu',   # 64x64
        'block_3_expand_relu',   # 32x32
        'block_6_expand_relu',   # 16x16
        'block_13_expand_relu',  # 8x8
        'block_16_project',      # 4x4
    ]
    layers = [base_model.get_layer(name).output for name in layer_names]
    # Create the feature extraction model
    down_stack = tf.keras.Model(inputs=base_model.input, outputs=layers)
    down_stack.trainable = False
    up_stack = [
        pix2pix.upsample(512, 3),  # 4x4 -> 8x8
        pix2pix.upsample(256, 3),  # 8x8 -> 16x16
        pix2pix.upsample(128, 3),  # 16x16 -> 32x32
        pix2pix.upsample(64, 3),   # 32x32 -> 64x64
    ]
    
    def unet_model(output_channels):
        inputs = tf.keras.layers.Input(shape=[128, 128, 3])
        x = inputs
        # Downsampling through the model
        skips = down_stack(x)
        x = skips[-1]
        skips = reversed(skips[:-1])
        for up, skip in zip(up_stack, skips):
            x = up(x)
            concat = tf.keras.layers.Concatenate()
            x = concat([x, skip])
        last = tf.keras.layers.Conv2DTranspose(
            output_channels, 3, strides=2,
            padding='same')  #64x64 -> 128x128
        x = last(x)
        return tf.keras.Model(inputs=inputs, outputs=x)
    
    model = unet_model(OUTPUT_CHANNELS)
    model.compile(optimizer='adam',
                  loss=tf.keras.losses.SparseCategoricalCrossentropy(from_logits=True),
                  metrics=['accuracy'])
    tf.keras.utils.plot_model(model, show_shapes=True)
    
    
    for image, mask in train_data.take(1):
        sample_image, sample_mask = image, mask
    display([sample_image, sample_mask])
    
    def create_mask(pred_mask):
        pred_mask = tf.argmax(pred_mask, axis=-1)
        pred_mask = pred_mask[..., tf.newaxis]
        return pred_mask[0]
    
    def show_predictions(dataset=None, num=1):
        if dataset:
            for image, mask in dataset.take(num):
                pred_mask = model.predict(image)
                display([image[0], mask[0], create_mask(pred_mask)])
        else:
            display([sample_image, sample_mask,
                 create_mask(model.predict(sample_image[tf.newaxis, ...]))])
    
    show_predictions()
    
    
    class DisplayCallback(tf.keras.callbacks.Callback):
        def on_epoch_end(self, epoch, logs=None):
            clear_output(wait=True)
            show_predictions()
            print ('\nSample Prediction after epoch {}\n'.format(epoch+1))
    
    model_history = model.fit(train_batched_data, epochs=EPOCHS,
                              #validation_data=val_batched_data,
                              callbacks=[DisplayCallback()]
                             )

说明：

执行这个代码之前需要的准备工作：

（1）下载数据集，此次数据集使用的是LIP数据集，不过此次我对数据集的下载好的数据位置进行了调整，方便数据读取

（2）下载[tensorflow\_examples][tensorflow_examples]的文件放置在指定的路径（我是放置在/opt/LIP/examples）

（3）一定要使用tf-2.3版本，以下的版本很容易出错，特别的低于2.0的

最终保存了模型文件 ，大小在60兆左右

本次代码主要参考：[https://tensorflow.google.cn/tutorials/images/segmentation][https_tensorflow.google.cn_tutorials_images_segmentation]

准确率：

![20200925183321813.png][]

效果不是很好，但是也还可以使用了 ，毕竟也就训练了20轮

对于模型文件MobileNetV2，如果代码拉取下载很慢可以提前下好放在这个路径下面就行：/root/.keras/ models/

可以看一下：

![20200925184141313.png][]

因为这个自动下载的路径 就是下载到/root/.keras/ models/这里

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3pob3VfNDM4_size_16_color_FFFFFF_t_70]: /images/20221123/ecd93982d39f4753bb87eb64ad127ca2.png
[tensorflow_examples]: https://github.com/tensorflow/examples.git
[https_tensorflow.google.cn_tutorials_images_segmentation]: https://tensorflow.google.cn/tutorials/images/segmentation
[20200925183321813.png]: /images/20221123/5addb05d37f14216afd23c8e21b32c0f.png
[20200925184141313.png]: /images/20221123/e85606ccdbb1440ca22851056e084346.png