我正在运行MNIST示例,并对图层进行了一些手动更改 . 虽然训练一切都很好,但最终测试精度达到了99% . 我现在正在尝试使用pycaffe在python中使用生成的模型,并按照给定here的步骤操作 . 我想计算混淆矩阵,所以我从LMDB逐个循环测试图像,然后运行网络 . 这是代码:

net = caffe.Net(args.proto, args.model, caffe.TEST)
...
datum = caffe.proto.caffe_pb2.Datum()
datum.ParseFromString(value)
label = int(datum.label)
image = caffe.io.datum_to_array(datum).astype(np.uint8)
...
net.blobs['data'].reshape(1, 1, 28, 28) # Greyscale 28x28 images
net.blobs['data'].data[...] = image
net.forward()
# Get predicted label
print net.blobs['label'].data[0] # use this later for confusion matrix

这是我的网络定义原型

name: "MNISTNet"
layer {
  name: "mnist"
  type: "Data"
  top: "data"
  top: "label"
  include {
    phase: TRAIN
  }
  transform_param {
    scale: 0.00390625
  }
  data_param {
    source: "train_lmdb"
    batch_size: 64
    backend: LMDB
  }
}
layer {
  name: "mnist"
  type: "Data"
  top: "data"
  top: "label"
  include {
    phase: TEST
  }
  transform_param {
    scale: 0.00390625
  }
  data_param {
    source: "test_lmdb"
    batch_size: 100
    backend: LMDB
  }
}
layer {
  name: "conv1"
  type: "Convolution"
  bottom: "data"
  top: "conv1"
  param {
    lr_mult: 1
  }
  param {
    lr_mult: 2
  }
  convolution_param {
    num_output: 20
    kernel_size: 5
    stride: 1
    weight_filler {
      type: "xavier"
    }
    bias_filler {
      type: "constant"
    }
  }
}
layer {
  name: "relu1"
  type: "ReLU"
  bottom: "conv1"
  top: "conv1"
}
layer {
  name: "pool1"
  type: "Pooling"
  bottom: "conv1"
  top: "pool1"
  pooling_param {
    pool: MAX
    kernel_size: 2
    stride: 2
  }
}
layer {
  name: "conv2"
  type: "Convolution"
  bottom: "pool1"
  top: "conv2"
  param {
    lr_mult: 1
  }
  param {
    lr_mult: 2
  }
  convolution_param {
    num_output: 50
    kernel_size: 5
    stride: 1
    weight_filler {
      type: "xavier"
    }
    bias_filler {
      type: "constant"
    }
  }
}
layer {
  name: "relu2"
  type: "ReLU"
  bottom: "conv2"
  top: "conv2"
}
layer {
  name: "pool2"
  type: "Pooling"
  bottom: "conv2"
  top: "pool2"
  pooling_param {
    pool: MAX
    kernel_size: 2
    stride: 2
  }
}
layer {
  name: "fc1"
  type: "InnerProduct"
  bottom: "pool2"
  top: "fc1"
  param {
    lr_mult: 1
  }
  param {
    lr_mult: 2
  }
  inner_product_param {
    num_output: 500
    weight_filler {
      type: "xavier"
    }
    bias_filler {
      type: "constant"
    }
  }
}
layer {
  name: "relu3"
  type: "ReLU"
  bottom: "fc1"
  top: "fc1"
}
layer {
  name: "fc2"
  type: "InnerProduct"
  bottom: "fc1"
  top: "fc2"
  param {
    lr_mult: 1
  }
  param {
    lr_mult: 2
  }
  inner_product_param {
    num_output: 10
    weight_filler {
      type: "xavier"
    }
    bias_filler {
      type: "constant"
    }
  }
}
layer {
  name: "loss"
  type: "SoftmaxWithLoss"
  bottom: "fc2"
  bottom: "label"
}
layer {
  name: "accuracy"
  type: "Accuracy"
  bottom: "fc2"
  bottom: "label"
  top: "accuracy"
  include {
    phase: TEST
  }
}

请注意,测试批量大小为100,这就是我需要在python代码中重新整形的原因 . 现在,假设我将测试批量大小更改为1,完全相同的python代码打印出不同的(并且大多数是正确的)预测类标签 . 因此,以批量大小1运行的代码产生预期结果,准确度大约为99%,而批量大小100则非常糟糕 . 但是,基于Imagenet pycaffe教程,我看不出我做错了什么 . 作为最后的手段,我可以创建一个批量大小为1的原型文本的副本进行测试,并在我的python代码中使用,并在训练时使用原始的,但这并不理想 .

此外,我不认为它应该是预处理的问题,因为它不能解释为什么它适用于批量大小1 .

任何指针赞赏!