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CONTRIBUTING.md

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+# How to become a contributor and submit your own code
+
+## Contributor License Agreements
+
+We'd love to accept your sample apps and patches! Before we can take them, we
+have to jump a couple of legal hurdles.
+
+Please fill out either the individual or corporate Contributor License Agreement (CLA).
+
+  * If you are an individual writing original source code and you're sure you
+    own the intellectual property, then you'll need to sign an [individual CLA]
+    (https://cla.developers.google.com).
+  * If you work for a company that wants to allow you to contribute your work,
+    then you'll need to sign a [corporate CLA]
+    (https://cla.developers.google.com).
+
+Follow either of the two links above to access the appropriate CLA and
+instructions for how to sign and return it. Once we receive it, we'll be able to
+accept your pull requests.
+
+## Contributing A Patch
+
+1. Submit an issue describing your proposed change to the repo in question.
+1. The repo owner will respond to your issue promptly.
+1. If your proposed change is accepted, and you haven't already done so, sign a
+   Contributor License Agreement (see details above).
+1. Fork the desired repo, develop and test your code changes.
+1. Ensure that your code adheres to the existing style in the sample to which
+   you are contributing. Refer to the
+   [Android Code Style Guide]
+   (https://source.android.com/source/code-style.html) for the
+   recommended coding standards for this organization.
+1. Ensure that your code has an appropriate set of unit tests which all pass.
+1. Submit a pull request.

README.md

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-# CameraView #
+# CameraView
 
-CameraView
+*This is a preview release. The API is subject to change.*
+
+This is not an official Google product.
+
+CameraView aims to help Android developers easily integrate Camera features.
+
+Requires API Level 14. The library uses Camera 1 API on API Level 14-20 and Camera2 on 21 and above.
+
+## Features
+
+- Camera preview by placing it in a layout XML (and calling the start method)
+- Configuration by attributes
+  - Aspect ratio (app:aspectRatio)
+  - Auto-focus (app:autoFocus)
+  - Flash (app:flash)
+
+## Usage
+
+```xml
+<com.google.android.cameraview.CameraView
+    android:id="@+id/camera"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:keepScreenOn="true"
+    android:adjustViewBounds="true"
+    app:autoFocus="true"
+    app:aspectRatio="4:3"
+    app:facing="back"
+    app:flash="auto"/>
+```
+
+```java
+    @Override
+    protected void onResume() {
+        super.onResume();
+        mCameraView.start();
+    }
+
+    @Override
+    protected void onPause() {
+        mCameraView.stop();
+        super.onPause();
+    }
+```
+
+You can see a complete usage in the demo app.
+
+## Contribution
+
+See [CONTRIBUTING.md](/CONTRIBUTING.md).