mindspore/docs/api/api_python/nn/mindspore.nn.ImageGradients...

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mindspore.nn.ImageGradients
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.. py:class:: mindspore.nn.ImageGradients
计算每个颜色通道的图像渐变返回为两个Tensor分别表示高和宽方向上的变化率。
假设图像shape为 :math:`h*w` ,则沿高和宽的梯度分别为 :math:`dy`:math:`dx`
.. math::
dy[i] = \begin{cases} image[i+1, :]-image[i, :], &if\ 0<=i<h-1 \cr
0, &if\ i==h-1\end{cases}
dx[i] = \begin{cases} image[:, i+1]-image[:, i], &if\ 0<=i<w-1 \cr
0, &if\ i==w-1\end{cases}
输入:
- **images** (Tensor) - 输入图像数据,格式为'NCHW'。
输出:
- **dy** (Tensor) - 垂直方向的图像梯度数据类型和shape与输入相同。
- **dx** (Tensor) - 水平方向的图像梯度数据类型和shape与输入相同。
异常:
- **ValueError** - `images` 的shape长度不等于4。