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---
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layout: page
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title: "Frame Processing"
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subtitle: "Process each frame in real time"
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description: "Process each frame in real time"
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category: docs
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order: 5
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date: 2018-12-20 20:45:42
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disqus: 1
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---
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We support frame processors that will receive data from the camera preview stream. This is a useful
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feature with a wide range of applications. For example, the frames can be sent to a face detector,
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a QR code detector, the
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[Firebase Machine Learning Kit](https://firebase.google.com/products/ml-kit/), or any other frame consumer.
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```java
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cameraView.addFrameProcessor(new FrameProcessor() {
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@Override
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@WorkerThread
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public void process(Frame frame) {
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byte[] data = frame.getData();
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int rotation = frame.getRotation();
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long time = frame.getTime();
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Size size = frame.getSize();
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int format = frame.getFormat();
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// Process...
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}
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}
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```
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For your convenience, the `FrameProcessor` method is run in a background thread so you can do your job
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in a synchronous fashion. Once the process method returns, internally we will re-use the `Frame` instance and
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apply new data to it. So:
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- you can do your job synchronously in the `process()` method
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- if you must hold the `Frame` instance longer, use `frame = frame.freeze()` to get a frozen instance
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that will not be affected
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### Related APIs
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|Frame API|Type|Description|
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|---------|----|-----------|
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|`camera.addFrameProcessor(FrameProcessor)`|`-`|Register a `FrameProcessor`.|
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|`frame.getData()`|`byte[]`|The current preview frame, in its original orientation.|
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|`frame.getTime()`|`long`|The preview timestamp, in `System.currentTimeMillis()` reference.|
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|`frame.getRotation()`|`int`|The rotation that should be applied to the byte array in order to see what the user sees.|
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|`frame.getSize()`|`Size`|The frame size, before any rotation is applied, to access data.|
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|`frame.getFormat()`|`int`|The frame `ImageFormat`. This will always be `ImageFormat.NV21` for now.|
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|`frame.freeze()`|`Frame`|Clones this frame and makes it immutable. Can be expensive because requires copying the byte array.|
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|`frame.release()`|`-`|Disposes the content of this frame. Should be used on frozen frames to release memory.|
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