题
我正在尝试加载预训练网络,我收到以下错误
F1101 23:03:41.857909 73 net.cpp:757] Cannot copy param 0 weights
from layer ‘fc4’; shape mismatch. Source param shape is 512 4096
(2097152); target param shape is 512 256 4 4 (2097152). To learn this
layer’s parameters from scratch rather than copying from a saved net,
rename the layer.
我注意到512 x 256 x 4 x 4 == 512 x 4096,所以似乎在保存和重新加载网络权重时,图层以某种方式被展平.
我该如何抵消这个错误?
重现
我正试图在this GitHub repository中使用D-CNN预训练网络.
我加载网络
import caffe
net = caffe.Net('deploy_D-CNN.prototxt','D-CNN.caffemodel',caffe.TEST)
原型文件是
name: "D-CNN"
input: "data"
input_dim: 10
input_dim: 3
input_dim: 259
input_dim: 259
layer {
name: "conv1"
type: "Convolution"
bottom: "data"
top: "conv1"
convolution_param {
num_output: 64
kernel_size: 5
stride: 2
}
}
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: "norm1"
type: "LRN"
bottom: "pool1"
top: "norm1"
lrn_param {
local_size: 5
alpha: 0.0001
beta: 0.75
}
}
layer {
name: "conv2"
type: "Convolution"
bottom: "norm1"
top: "conv2"
convolution_param {
num_output: 128
pad: 1
kernel_size: 3
}
}
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: "conv3"
type: "Convolution"
bottom: "pool2"
top: "conv3"
convolution_param {
num_output: 256
pad: 1
kernel_size: 3
stride: 1
}
}
layer {
name: "relu3"
type: "ReLU"
bottom: "conv3"
top: "conv3"
}
layer {
name: "fc4"
type: "Convolution"
bottom: "conv3"
top: "fc4"
convolution_param {
num_output: 512
pad: 0
kernel_size: 4
}
}
layer {
name: "relu4"
type: "ReLU"
bottom: "fc4"
top: "fc4"
}
layer {
name: "drop4"
type: "Dropout"
bottom: "fc4"
top: "fc4"
dropout_param {
dropout_ratio: 0.5
}
}
layer {
name: "pool5_spm3"
type: "Pooling"
bottom: "fc4"
top: "pool5_spm3"
pooling_param {
pool: MAX
kernel_size: 10
stride: 10
}
}
layer {
name: "pool5_spm3_flatten"
type: "Flatten"
bottom: "pool5_spm3"
top: "pool5_spm3_flatten"
}
layer {
name: "pool5_spm2"
type: "Pooling"
bottom: "fc4"
top: "pool5_spm2"
pooling_param {
pool: MAX
kernel_size: 14
stride: 14
}
}
layer {
name: "pool5_spm2_flatten"
type: "Flatten"
bottom: "pool5_spm2"
top: "pool5_spm2_flatten"
}
layer {
name: "pool5_spm1"
type: "Pooling"
bottom: "fc4"
top: "pool5_spm1"
pooling_param {
pool: MAX
kernel_size: 29
stride: 29
}
}
layer {
name: "pool5_spm1_flatten"
type: "Flatten"
bottom: "pool5_spm1"
top: "pool5_spm1_flatten"
}
layer {
name: "pool5_spm"
type: "Concat"
bottom: "pool5_spm1_flatten"
bottom: "pool5_spm2_flatten"
bottom: "pool5_spm3_flatten"
top: "pool5_spm"
concat_param {
concat_dim: 1
}
}
layer {
name: "fc4_2"
type: "InnerProduct"
bottom: "pool5_spm"
top: "fc4_2"
param {
lr_mult: 1
decay_mult: 1
}
param {
lr_mult: 2
decay_mult: 0
}
inner_product_param {
num_output: 512
weight_filler {
type: "gaussian"
std: 0.005
}
bias_filler {
type: "constant"
value: 0.1
}
}
}
layer {
name: "relu4"
type: "ReLU"
bottom: "fc4_2"
top: "fc4_2"
}
layer {
name: "drop4"
type: "Dropout"
bottom: "fc4_2"
top: "fc4_2"
dropout_param {
dropout_ratio: 0.5
}
}
layer {
name: "fc5"
type: "InnerProduct"
bottom: "fc4_2"
top: "fc5"
param {
lr_mult: 1
decay_mult: 1
}
param {
lr_mult: 2
decay_mult: 0
}
inner_product_param {
num_output: 19
weight_filler {
type: "gaussian"
std: 0.01
}
bias_filler {
type: "constant"
value: 0
}
}
}
layer {
name: "prob"
type: "Softmax"
bottom: "fc5"
top: "prob"
}
最佳答案
看起来你正在采用预训练网,其中“fc4”层是一个完全连接的层(又名类型:“InnerProduct”层),它被“重新塑造”成卷积层.
由于内积层和卷积层对输入执行大致相同的线性运算,因此可以在某些假设下进行这种改变(参见例如here).
正如您已经正确识别的那样,原始预训练的完全连接层的权重被保存为“扁平化”,因为形状可以预期卷积层.
由于内积层和卷积层对输入执行大致相同的线性运算,因此可以在某些假设下进行这种改变(参见例如here).
正如您已经正确识别的那样,原始预训练的完全连接层的权重被保存为“扁平化”,因为形状可以预期卷积层.
我认为这个问题的解决方案可以使用share_mode: PERMISSIVE
:
layer {
name: "fc4"
type: "Convolution"
bottom: "conv3"
top: "fc4"
convolution_param {
num_output: 512
pad: 0
kernel_size: 4
}
param {
lr_mult: 1
decay_mult: 1
share_mode: PERMISSIVE # should help caffe overcome the shape mismatch
}
param {
lr_mult: 2
decay_mult: 0
share_mode: PERMISSIVE
}
}