| <?xml version="1.0" encoding="UTF-8"?> |
| <!-- |
| Copyright 2014 The Android Open Source Project |
| |
| Licensed under the Apache License, Version 2.0 (the "License"); |
| you may not use this file except in compliance with the License. |
| You may obtain a copy of the License at |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| Unless required by applicable law or agreed to in writing, software |
| distributed under the License is distributed on an "AS IS" BASIS, |
| WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| See the License for the specific language governing permissions and |
| limitations under the License. |
| --> |
| <sample> |
| <name>HdrViewfinder</name> |
| <group>Media</group> |
| <package>com.example.android.hdrviewfinder</package> |
| |
| <minSdk>21</minSdk> |
| <targetSdkVersion>23</targetSdkVersion> |
| <compileSdkVersion>23</compileSdkVersion> |
| |
| <strings> |
| <intro> |
| <![CDATA[ |
| This demo implements a real-time high-dynamic-range camera viewfinder, by alternating |
| the sensor\'s exposure time between two exposure values on even and odd frames, and then |
| compositing together the latest two frames whenever a new frame is captured. |
| ]]> |
| </intro> |
| </strings> |
| |
| <template src="base"/> |
| |
| <metadata> |
| <status>PUBLISHED</status> |
| <categories>Media</categories> |
| <technologies>Android</technologies> |
| <languages>Java</languages> |
| <solutions>Mobile</solutions> |
| <level>ADVANCED</level> |
| <icon>big_icon.png</icon> |
| <screenshots> |
| <img>screenshots/image1.png</img> |
| </screenshots> |
| <api_refs> |
| <android>android.hardware.camera2.CameraAccessException</android> |
| <android>android.hardware.camera2.CameraCaptureSession</android> |
| <android>android.hardware.camera2.CameraCharacteristics</android> |
| <android>android.hardware.camera2.CameraDevice</android> |
| <android>android.hardware.camera2.CameraManager</android> |
| <android>android.hardware.camera2.CaptureRequest</android> |
| <android>android.hardware.camera2.CaptureResult</android> |
| <android>android.hardware.camera2.TotalCaptureResult</android> |
| </api_refs> |
| |
| <description> |
| <![CDATA[ |
| This demo implements a real-time high-dynamic-range camera viewfinder, by alternating |
| the sensor's exposure time between two exposure values on even and odd frames, and then |
| compositing together the latest two frames whenever a new frame is captured. |
| ]]> |
| </description> |
| |
| <intro> |
| <![CDATA[ |
| A small demo of advanced camera functionality with the Android camera2 API. |
| |
| This demo implements a real-time high-dynamic-range camera viewfinder, |
| by alternating the sensor's exposure time between two exposure values on even and odd |
| frames, and then compositing together the latest two frames whenever a new frame is |
| captured. |
| |
| The demo has three modes: Regular auto-exposure viewfinder, split-screen manual exposure, |
| and the fused HDR viewfinder. The latter two use manual exposure controlled by the user, |
| by swiping up/down on the right and left halves of the viewfinder. The left half controls |
| the exposure time of even frames, and the right half controls the exposure time of odd frames. |
| |
| In split-screen mode, the even frames are shown on the left and the odd frames on the right, |
| so the user can see two different exposures of the scene simultaneously. In fused HDR mode, |
| the even/odd frames are merged together into a single image. By selecting different exposure |
| values for the even/odd frames, the fused image has a higher dynamic range than the regular |
| viewfinder. |
| |
| The HDR fusion and the split-screen viewfinder processing is done with RenderScript; as is the |
| necessary YUV->RGB conversion. The camera subsystem outputs YUV images naturally, while the GPU |
| and display subsystems generally only accept RGB data. Therefore, after the images are |
| fused/composited, a standard YUV->RGB color transform is applied before the the data is written |
| to the output Allocation. The HDR fusion algorithm is very simple, and tends to result in |
| lower-contrast scenes, but has very few artifacts and can run very fast. |
| |
| Data is passed between the subsystems (camera, RenderScript, and display) using the |
| Android [android.view.Surface][1] class, which allows for zero-copy transport of large |
| buffers between processes and subsystems. |
| |
| [1]: http://developer.android.com/reference/android/view/Surface.html |
| ]]> |
| </intro> |
| </metadata> |
| |
| </sample> |