.py | 深度学习暑期学校知识点

MountAye

Aug 17, 2022


  • 电脑设置、python 入门
    • NoMachine, ssh, python, conda, jupyter
    • 文件夹操作 pathlib, 图片操作 skimage
    • 数据增强 (data augmentation): imgaug
    • TensorBoard
  • 机器学习简介
    • Linear Classifier
    • sklearn**.**model_selection**.**train_test_split()
    • Stochastic gradient descent
    • TensorFlow:
      • tensorflow_addons as tfa
      • tfa.image.rotate(), tf.image.random_flip_left_right()
      • **from** tensorflow.keras **import** Model, **from** tensorflow.keras.models **import** Sequential, **from** tensorflow.keras.layers **import** Input, Flatten, Dense, Activation, BatchNormalization, Conv2D, MaxPool2D, Softmax
      • tf**.**keras**.**losses**.**CategoricalCrossentropy(), tf**.**keras**.**optimizers**.**Adam(lr**=**1e-3, clipnorm**=**0.001)
      • linear_classifier **=**Model(...), linear_classifier.compile(), linear_classifier.fit(), linear_classifier.predict()
  • 深度学习简介
    • Perceptron
    • Perceptron-based XOR gate
    • decision boundary of your model: np.meshgrid
  • 图像恢复 (image restoration)
    • CARE network
    • Noise2Nosie, Noise2Void
  • 图像翻译 (image translation)
    • micro-DL: a tool to generate and train U-net from config files.
  • 图像语义分割 (image semantic segmentation): 比较详细,前两节有点水了。
    • **from** PIL **import** Image, **import** imageio, **from** torchvision **import** transforms
    • **from** torch.utils.data **import** Dataset, DataLoader, **import** torch.nn **as** nn, **from** torch.nn **import** functional **as** F, **from** torch.utils.tensorboard **import** SummaryWriter,
    • U-net on PyTorch
  • 图像实例分割 (instance segmentation)
    1. Foreground segmentation:
      • Receptive Field of View: The term is borrowed from biology where it describes the “portion of sensory space that can elicit neuronal responses when stimulated” (wikipedia). Each output pixel can look at/depends on an input patch with that diameter centered at its position. Based on this patch, the network has to be able to make a decision about the prediction for the respective pixel.
      • Early Stopping to avoid overfitting: define an EarlyStopping class
    2. Instance Segmentation:
      • Ideas:
        • Three-class model (foreground, background, boundary),
        • Distance transform (label for each pixel is the distance to the closest boundary),
        • Edge affinity (consider not just the pixel but also its direct neighbors, predicts the probability that there is an edge, this is called affinity.) 听的时候懂了,回来看的时候没太看懂
        • Metric learning (learns to predict an embedding vector for each pixel.)
    3. Tile and Stitch:
      • 当需要处理的图片过大时,将图片切分成多个小图,分别预测之后拼接在一起。
      • 文中说图片尺寸不是 某个参数的整数倍的时候拼贴结果会不连续,但是代码注释中说等于这个整数倍的时候会不连续,晕。
      • https://arxiv.org/pdf/2101.05846.pdf
    4. 一个实例,epithelia cells
  • 失败模式:极其之水,就是科普了一下训练参数错误的后果,以及一点对抗学习的内容
  • 追踪:比较水,因为机器学习追踪的运算量极大,且主讲人感觉就是来做广告的,所以就直接用 CoLab 体验了一下就完事了。(就这还加州理工呢~)
  • 知识提取:
    • 前面的基本上是从像素到像素的映射,这里的知识提取是从图片到标签的映射。
    • CycleGAN
    • Create a balanced Dataloader