一句一句解释class CSPStage(nn.Layer): def __init__(self, block_fn, ch_in, ch_out, n, act='swish', spp=False): super(CSPStage, self).__init__() ch_mid = int(ch_out // 2) self.conv1 = ConvBNLayer(ch_in, ch_mid, 1, act=act) self.conv2 = ConvBNLayer(ch_in, ch_mid, 1, act=act) self.convs = nn.Sequential() next_ch_in = ch_mid for i in range(n): self.convs.add_sublayer( str(i), eval(block_fn)(next_ch_in, ch_mid, act=act, shortcut=False)) if i == (n - 1) // 2 and spp: self.convs.add_sublayer( 'spp', SPP(ch_mid * 4, ch_mid, 1, [5, 9, 13], act=act)) next_ch_in = ch_mid self.conv3 = ConvBNLayer(ch_mid * 2, ch_out, 1, act=act) def forward(self, x): y1 = self.conv1(x) y2 = self.conv2(x) y2 = self.convs(y2) y = paddle.concat([y1, y2], axis=1) y = self.conv3(y) return y
时间: 2024-04-27 16:25:35 浏览: 20
这段代码定义了一个名为CSPStage的类,继承自paddle.nn.Layer类。它有四个输入参数:block_fn、ch_in、ch_out、n和act='swish'(默认为'swish')和spp=False(默认为False)。
在__init__函数中,它首先计算了中间通道数ch_mid(输出通道数的一半),然后定义了两个卷积层self.conv1和self.conv2,分别将输入的通道数ch_in分别减半,并使用指定的激活函数act。接下来,它定义了一个包含多个卷积层的序列self.convs,具体数量由输入的n决定,每个卷积层都是由block_fn指定的块函数,块函数的输入通道数为next_ch_in,输出通道数为ch_mid,同时将输入的通道数next_ch_in更新为ch_mid。如果输入的spp为True并且已经处理到了第(n-1)//2层,那么会在序列中添加一个SPP(Spatial Pyramid Pooling)层,这个层将输入的通道数翻倍并使用指定的池化核大小[5,9,13]进行金字塔池化,最后输出通道数为ch_mid。最后,它定义了一个卷积层self.conv3,将序列中所有卷积层的输出通道数concat起来,最终输出通道数为ch_out。
在forward函数中,它首先分别对输入x进行了两次卷积,得到了y1和y2。然后将y2输入到序列self.convs中,得到了y2的输出。接着,将y1和y2的输出在通道维度上concat起来,最后再通过卷积层self.conv3输出。
相关问题
补全以下代码class LeNet(paddle.nn.Layer): def __init__(self):
class LeNet(paddle.nn.Layer):
def __init__(self):
super(LeNet, self).__init__()
# 定义第一个卷积层,输入通道数为1,输出通道数为6,卷积核大小为5*5
self.conv1 = paddle.nn.Conv2D(in_channels=1, out_channels=6, kernel_size=5)
# 定义第二个卷积层,输入通道数为6,输出通道数为16,卷积核大小为5*5
self.conv2 = paddle.nn.Conv2D(in_channels=6, out_channels=16, kernel_size=5)
# 定义第三个全连接层,输入神经元个数为16*5*5,输出神经元个数为120
self.fc1 = paddle.nn.Linear(in_features=16*5*5, out_features=120)
# 定义第四个全连接层,输入神经元个数为120,输出神经元个数为84
self.fc2 = paddle.nn.Linear(in_features=120, out_features=84)
# 定义第五个全连接层,输入神经元个数为84,输出神经元个数为10
self.fc3 = paddle.nn.Linear(in_features=84, out_features=10)
def forward(self, x):
# 卷积层->激活函数->池化层
x = F.relu(self.conv1(x))
x = F.max_pool2d(x, kernel_size=2, stride=2)
# 卷积层->激活函数->池化层
x = F.relu(self.conv2(x))
x = F.max_pool2d(x, kernel_size=2, stride=2)
# 将tensor展开成一维的
x = paddle.flatten(x, start_axis=1, stop_axis=-1)
# 三个全连接层->激活函数
x = F.relu(self.fc1(x))
x = F.relu(self.fc2(x))
x = self.fc3(x)
return x
补全以下LeNet网络模型代码class LeNet(paddle.nn.Layer): def __init__(self):
class LeNet(paddle.nn.Layer):
def __init__(self):
super(LeNet, self).__init__()
self.conv1 = paddle.nn.Conv2D(in_channels=1, out_channels=6, kernel_size=5, stride=1, padding=2)
self.pool1 = paddle.nn.MaxPool2D(kernel_size=2, stride=2)
self.conv2 = paddle.nn.Conv2D(in_channels=6, out_channels=16, kernel_size=5, stride=1)
self.pool2 = paddle.nn.MaxPool2D(kernel_size=2, stride=2)
self.fc1 = paddle.nn.Linear(in_features=16*5*5, out_features=120)
self.fc2 = paddle.nn.Linear(in_features=120, out_features=84)
self.fc3 = paddle.nn.Linear(in_features=84, out_features=10)
def forward(self, x):
x = self.conv1(x)
x = F.relu(x)
x = self.pool1(x)
x = self.conv2(x)
x = F.relu(x)
x = self.pool2(x)
x = paddle.flatten(x, start_axis=1, stop_axis=-1)
x = self.fc1(x)
x = F.relu(x)
x = self.fc2(x)
x = F.relu(x)
x = self.fc3(x)
return x