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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，我的最终测试准确率达到了 ~99%。我现在正在尝试使用 pycaffe 在 python 中使用生成的模型，并按照此处给出的步骤进行操作。我想计算混淆矩阵，所以我从 LMDB 中一张一张地循环测试图像，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prototxt

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，这就是为什么我需要在 python 代码中进行重塑。现在，假设我将测试批次大小更改为 1，完全相同的 python 代码会打印不同的（并且大部分是正确的）预测类标签。因此，批处理大小为 1 的代码会产生预期的结果，准确率约为 99%，而批处理大小为 100 则很糟糕。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 prototxt 副本进行测试，并在我的 python 代码中使用它，并在训练时使用原始的，但这并不理想。

另外，我认为这不应该是预处理的问题，因为它没有解释为什么它适用于批量大小 1。

任何指针表示赞赏！

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