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openvino/docs/ops/movement/DepthToSpace_1.md

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## DepthToSpace <a name="DepthToSpace"></a> {#openvino_docs_ops_movement_DepthToSpace_1}
2020-06-19 14:39:57 +03:00
**Versioned name**: *DepthToSpace-1*
**Category**: *Data movement*
**Short description**: *DepthToSpace* operation rearranges data from the depth dimension of the input tensor into spatial dimensions of the output tensor.
**Attributes**
* *block_size*
* **Description**: *block_size* specifies the size of the value block to be moved. The depth dimension size must be evenly divided by `block_size ^ (len(input.shape) - 2)`.
* **Range of values**: a positive integer
* **Type**: `int`
* **Default value**: 1
* **Required**: *no*
* *mode*
* **Description**: specifies how the input depth dimension is split to block coordinates and the new depth dimension.
* **Range of values**:
* *blocks_first*: the input depth is divided to `[block_size, ..., block_size, new_depth]`
* *depth_first*: the input depth is divided to `[new_depth, block_size, ..., block_size]`
* **Type**: `string`
* **Default value**: None
* **Required**: *yes*
**Inputs**
* **1**: `data` - input tensor of any type with rank >= 3. Required.
**Outputs**
* **1**: permuted tensor with shape `[N, C / block_size ^ K, D1 * block_size, D2 * block_size, ..., DK * block_size]`.
**Detailed description**
*DepthToSpace* operation permutes elements from the input tensor with shape `[N, C, D1, D2, ..., DK]`, to the output tensor where values from the input depth dimension (features) `C` are moved to spatial blocks in `D1`, ..., `DK`. Refer to the [ONNX* specification](https://github.com/onnx/onnx/blob/master/docs/Operators.md#DepthToSpace) for an example of the 4D input tensor case.
The operation is equivalent to the following transformation of the input tensor `data` with `K` spatial dimensions of shape `[N, C, D1, D2, ..., DK]` to *Y* output tensor. If `mode = blocks_first`:
x' = reshape(data, [N, block_size, block_size, ..., block_size, C / (block_size ^ K), D1, D2, ..., DK])
x'' = transpose(x', [0, K + 1, K + 2, 1, K + 3, 2, K + 4, 3, ..., K + (K + 1), K])
y = reshape(x'', [N, C / (block_size ^ K), D1 * block_size, D2 * block_size, D3 * block_size, ..., DK * block_size])
If `mode = depth_first`:
x' = reshape(data, [N, C / (block_size ^ K), block_size, block_size, ..., block_size, D1, D2, ..., DK])
x'' = transpose(x', [0, 1, K + 2, 2, K + 3, 3, K + 4, 4, ..., K + (K + 1), K + 1])
y = reshape(x'', [N, C / (block_size ^ K), D1 * block_size, D2 * block_size, D3 * block_size, ..., DK * block_size])
**Example**
```xml
<layer type="DepthToSpace" ...>
<data block_size="2" mode="blocks_first"/>
<input>
<port id="0">
<dim>5</dim>
<dim>28</dim>
<dim>2</dim>
<dim>3</dim>
</port>
</input>
<output>
<port id="1">
<dim>5</dim> <!-- data.shape[0] -->
<dim>7</dim> <!-- data.shape[1] / (block_size ^ 2) -->
<dim>4</dim> <!-- data.shape[2] * block_size -->
<dim>6</dim> <!-- data.shape[3] * block_size -->
</port>
</output>
</layer>
```