1# Device Input Management (ArkTS)
2
3Before developing a camera application, request permissions by following the instructions provided in [Camera Development Preparations](camera-preparation.md).
4
5A camera application invokes and controls a camera device to perform basic operations such as preview, photo capture, and video recording.
6
7## How to Develop
8
9Read [Camera](../../reference/apis-camera-kit/js-apis-camera.md) for the API reference.
10
111. Import the camera module, which provides camera-related attributes and methods.
12
13   ```ts
14   import { camera } from '@kit.CameraKit';
15   import { BusinessError } from '@kit.BasicServicesKit';
16   ```
17
18   > **NOTE**
19   >
20   > Before any camera device input, you must complete camera management by following the instructions provided in [Camera Device Management](camera-device-management.md).
21
222. Call [createCameraInput](../../reference/apis-camera-kit/js-apis-camera.md#createcamerainput) in the [cameraManager](../../reference/apis-camera-kit/js-apis-camera.md#cameramanager) class to create a camera input stream.
23
24   ```ts
25   async function createInput(cameraDevice: camera.CameraDevice, cameraManager: camera.CameraManager): Promise<camera.CameraInput | undefined> {
26     // Create a camera input stream.
27     let cameraInput: camera.CameraInput | undefined = undefined;
28     try {
29       cameraInput = cameraManager.createCameraInput(cameraDevice);
30     } catch (error) {
31       let err = error as BusinessError;
32       console.error('Failed to createCameraInput errorCode = ' + err.code);
33     }
34     if (cameraInput === undefined) {
35       return undefined;
36     }
37     // Listen for camera input errors.
38     cameraInput.on('error', cameraDevice, (error: BusinessError) => {
39       console.error(`Camera input error code: ${error.code}`);
40     });
41     // Open the camera.
42     await cameraInput.open();
43     return cameraInput;
44   }
45   ```
46
473. Call [getSupportedSceneModes](../../reference/apis-camera-kit/js-apis-camera.md#getsupportedscenemodes11) to obtain the list of scene modes supported by the current camera device. The list stores all the [SceneModes](../../reference/apis-camera-kit/js-apis-camera.md#scenemode11) supported by the camera device.
48
49    ```ts
50    function getSupportedSceneMode(cameraDevice: camera.CameraDevice, cameraManager: camera.CameraManager): Array<camera.SceneMode> {
51      // Obtain the list of scene modes supported by the camera device.
52      let sceneModeArray: Array<camera.SceneMode> = cameraManager.getSupportedSceneModes(cameraDevice);
53      if (sceneModeArray != undefined && sceneModeArray.length > 0) {
54        for (let index = 0; index < sceneModeArray.length; index++) {
55          console.info('Camera SceneMode : ' + sceneModeArray[index]);
56      }
57        return sceneModeArray;
58      } else {
59          console.error("cameraManager.getSupportedSceneModes error");
60          return [];
61      }
62    }
63    ```
64
654. Call [getSupportedOutputCapability](../../reference/apis-camera-kit/js-apis-camera.md#getsupportedoutputcapability11) to obtain all output streams supported by the current camera device, such as preview streams, photo streams, and video streams. The supported output streams are listed in the **profile** field in [CameraOutputCapability](../../reference/apis-camera-kit/js-apis-camera.md#cameraoutputcapability). Different types of output streams must be added based on the value of [SceneMode](../../reference/apis-camera-kit/js-apis-camera.md#scenemode11) specified by the camera device.
66
67   ```ts
68   async function getSupportedOutputCapability(cameraDevice: camera.CameraDevice, cameraManager: camera.CameraManager, sceneMode: camera.SceneMode): Promise<camera.CameraOutputCapability | undefined> {
69      // Obtain the output streams supported by the camera device.
70      let cameraOutputCapability: camera.CameraOutputCapability = cameraManager.getSupportedOutputCapability(cameraDevice, sceneMode);
71      if (!cameraOutputCapability) {
72        console.error("cameraManager.getSupportedOutputCapability error");
73        return undefined;
74      }
75      console.info("outputCapability: " + JSON.stringify(cameraOutputCapability));
76      // The following uses the NORMAL_PHOTO mode as an example. You need to add the preview stream and photo stream.
77      // previewProfiles is the preview output streams supported by the current camera device.
78      let previewProfilesArray: Array<camera.Profile> = cameraOutputCapability.previewProfiles;
79      if (!previewProfilesArray) {
80        console.error("createOutput previewProfilesArray == null || undefined");
81      }
82      // photoProfiles is the photo output streams supported by the current camera device.
83      let photoProfilesArray: Array<camera.Profile> = cameraOutputCapability.photoProfiles;
84      if (!photoProfilesArray) {
85        console.error("createOutput photoProfilesArray == null || undefined");
86      }
87      return cameraOutputCapability;
88   }
89   ```
90