Yolo v5程序学习3

原创

已于 2024-09-22 14:14:10 修改

· 785 阅读

10 ·

版权

文章标签：

#YOLO #学习 #python

于 2024-09-22 14:13:12 首次发布

这篇还是common.py


class Focus(nn.Module):
    """Focuses spatial information into channel space using slicing and convolution for efficient feature extraction."""

    def __init__(self, c1, c2, k=1, s=1, p=None, g=1, act=True):
        """Initializes Focus module to concentrate width-height info into channel space with configurable convolution
        parameters.
        """
        super().__init__()
        self.conv = Conv(c1 * 4, c2, k, s, p, g, act=act)
        # self.contract = Contract(gain=2)

    def forward(self, x):
        """Processes input through Focus mechanism, reshaping (b,c,w,h) to (b,4c,w/2,h/2) then applies convolution."""
        return self.conv(torch.cat((x[..., ::2, ::2], x[..., 1::2, ::2], x[..., ::2, 1::2], x[..., 1::2, 1::2]), 1))
        # return self.conv(self.contract(x))

x[..., ::2, ::2], x[..., 1::2, ::2], x[..., ::2, 1::2], x[..., 1::2, 1::2]

以6*6举例

A = np.arange(36).reshape(6, 6)
A = torch.from_numpy(A)
C1 = A[..., ::2, ::2]
C2 = A[..., 1::2, ::2]
C3 = A[..., ::2, 1::2]
C4 = A[..., 1::2, 1::2]
C5 = torch.cat((C1, C2, C3, C4), 1)