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# Image Decode Implementation with CV2 and nvjpeg
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*author: junjie.jiang*
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<br />
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## Description
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An image decode operator implementation with OpenCV and nvjpeg.
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In CPU env, use OpenCV, in GPU env, use nvjpeg to decode jpeg files.
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<br />
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## Code Example
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Load a image from path './src_dog.jpg'.
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*Write the pipeline in simplified style:*
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```python
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from towhee import pipe, ops, DataCollection
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p = (
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pipe.input('url')
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.map('url', 'image', ops.image_decode.nvjpeg())
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.output('image')
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)
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DataCollection(p('./src_dog.jpg')).show()
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```
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<img src="./dog.jpg" height="150px"/>
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## Factory Constructor
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Create the operator via the following factory method:
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***ops.image_decode.nvjpeg()***
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<br />
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## Interface
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An image decode operator takes an image path as input. It decodes the image back to ndarray.
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**Parameters:**
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**img**: *str*
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Local file path or http url.
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**Returns**: *towhee.types.Image (a sub-class of numpy.ndarray)*
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The decoded image data as numpy.ndarray.
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