media_asset_manager_capi.h

Overview

The media_asset_manager_capi.h file declares the APIs of the media asset manager. You can use the functions to request media assets in the media library.

Library: libmedia_asset_manager.so

File to include:

System capability: SystemCapability.FileManagement.PhotoAccessHelper.Core

Since: 12

Related module: MediaAssetManager

Summary

Functions

|Name|Description| |–|–| |OH_MediaAssetManager* OH_MediaAssetManager_Create(void)|Creates an OH_MediaAssetManager instance.| |MediaLibrary_RequestId OH_MediaAssetManager_RequestImageForPath(OH_MediaAssetManager* manager, const char* uri,MediaLibrary_RequestOptions requestOptions, const char* destPath, OH_MediaLibrary_OnDataPrepared callback)|Requests an image in the specified directory.| |MediaLibrary_RequestId OH_MediaAssetManager_RequestVideoForPath(OH_MediaAssetManager* manager, const char* uri,MediaLibrary_RequestOptions requestOptions, const char* destPath, OH_MediaLibrary_OnDataPrepared callback)|Requests a video in the specified directory.| |bool OH_MediaAssetManager_CancelRequest(OH_MediaAssetManager* manager, const MediaLibrary_RequestId requestId)|Cancels a request based on the request ID.| |MediaLibrary_ErrorCode OH_MediaAssetManager_RequestMovingPhoto(OH_MediaAssetManager* manager,OH_MediaAsset* mediaAsset, MediaLibrary_RequestOptions requestOptions, MediaLibrary_RequestId* requestId,OH_MediaLibrary_OnMovingPhotoDataPrepared callback)|Requests a moving photo based on different policies.| |MediaLibrary_ErrorCode OH_MediaAssetManager_RequestImage(OH_MediaAssetManager* manager, OH_MediaAsset* mediaAsset,MediaLibrary_RequestOptions requestOptions, MediaLibrary_RequestId* requestId,OH_MediaLibrary_OnImageDataPrepared callback)|Requests an image based on different policies.| |MediaLibrary_ErrorCode OH_MediaAssetManager_Release(OH_MediaAssetManager* manager)|Releases an OH_MediaAssetManager instance.|

Function Description

OH_MediaAssetManager_Create()

OH_MediaAssetManager* OH_MediaAssetManager_Create(void)

Description

Creates an OH_MediaAssetManager instance.

Since: 12

Return value

|Type|Description| |–|–| |OH_MediaAssetManager*|Pointer to the OH_MediaAssetManager instance created.|

OH_MediaAssetManager_RequestImageForPath()

MediaLibrary_RequestId OH_MediaAssetManager_RequestImageForPath(OH_MediaAssetManager* manager, const char* uri,MediaLibrary_RequestOptions requestOptions, const char* destPath, OH_MediaLibrary_OnDataPrepared callback)

Description

Requests an image in the specified directory.

Required permissions: ohos.permission.READ_IMAGEVIDEO

Since: 12

Parameters

|Parameter|Description| |–|–| |OH_MediaAssetManager* manager|Pointer to the OH_MediaAssetManager instance.| |const char* uri|Pointer to the URI of the requested image.| |MediaLibrary_RequestOptions requestOptions|Options related to the media asset quality and delivery mode.| |const char* destPath|Pointer to the destination directory of the requested image.| |OH_MediaLibrary_OnDataPrepared callback|Callback to be invoked when the requested image is ready.|

Return value

|Type|Description| |–|–| |MediaLibrary_RequestId|Request ID.|

OH_MediaAssetManager_RequestVideoForPath()

MediaLibrary_RequestId OH_MediaAssetManager_RequestVideoForPath(OH_MediaAssetManager* manager, const char* uri,MediaLibrary_RequestOptions requestOptions, const char* destPath, OH_MediaLibrary_OnDataPrepared callback)

Description

Requests a video in the specified directory.

Required permissions: ohos.permission.READ_IMAGEVIDEO

Since: 12

Parameters

|Parameter|Description| |–|–| |OH_MediaAssetManager* manager|Pointer to the OH_MediaAssetManager instance.| |const char* uri|Pointer to the URI of the requested video.| |MediaLibrary_RequestOptions requestOptions|Options related to the media asset quality and delivery mode.| |const char* destPath|Pointer to the destination directory of the requested video.| |OH_MediaLibrary_OnDataPrepared callback|Callback to be invoked when the requested video is ready.|

Return value

|Type|Description| |–|–| |MediaLibrary_RequestId|Request ID.|

OH_MediaAssetManager_CancelRequest()

bool OH_MediaAssetManager_CancelRequest(OH_MediaAssetManager* manager, const MediaLibrary_RequestId requestId)

Description

Cancels a request based on the request ID.

Required permissions: ohos.permission.READ_IMAGEVIDEO

Since: 12

Parameters

|Parameter|Description| |–|–| |OH_MediaAssetManager* manager|Pointer to the OH_MediaAssetManager instance.| |const MediaLibrary_RequestId requestId|ID of the request to cancel.|

Return value

|Type|Description| |–|–| |bool|Operation result. The value true is returned if the request is successfully canceled, and false is returned otherwise.|

OH_MediaAssetManager_RequestMovingPhoto()

MediaLibrary_ErrorCode OH_MediaAssetManager_RequestMovingPhoto(OH_MediaAssetManager* manager,OH_MediaAsset* mediaAsset, MediaLibrary_RequestOptions requestOptions, MediaLibrary_RequestId* requestId,OH_MediaLibrary_OnMovingPhotoDataPrepared callback)

Description

Requests a moving photo based on different policies.

Required permissions: ohos.permission.READ_IMAGEVIDEO

Since: 13

Parameters

|Parameter|Description| |–|–| |OH_MediaAssetManager* manager|Pointer to the OH_MediaAssetManager instance.| |OH_MediaAsset* mediaAsset|Pointer to the OH_MediaAsset instance to be requested.| |MediaLibrary_RequestOptions requestOptions|Options related to the media asset quality and delivery mode. The options are specified by MediaLibrary_RequestOptions.| |MediaLibrary_RequestId* requestId|Request ID, which is specified by MediaLibrary_RequestId.| |OH_MediaLibrary_OnMovingPhotoDataPrepared callback|Callback to be invoked when the requested moving photo is ready. The callback is specified by OH_MediaLibrary_OnMovingPhotoDataPrepared.|

Return value

|Type|Description| |–|–| |MediaLibrary_ErrorCode|MEDIA_LIBRARY_OK: operation success.
MEDIA_LIBRARY_PARAMETER_ERROR: incorrect parameters. Possible causes:
1. A mandatory parameter is not specified.
2. A parameter type is incorrect.
3. Parameter verification fails.
MEDIA_LIBRARY_OPERATION_NOT_SUPPORTED: unsupported operation.
MEDIA_LIBRARY_PERMISSION_DENIED: no access permission.
MEDIA_LIBRARY_INTERNAL_SYSTEM_ERROR: internal system error.|

OH_MediaAssetManager_RequestImage()

MediaLibrary_ErrorCode OH_MediaAssetManager_RequestImage(OH_MediaAssetManager* manager, OH_MediaAsset* mediaAsset,MediaLibrary_RequestOptions requestOptions, MediaLibrary_RequestId* requestId,OH_MediaLibrary_OnImageDataPrepared callback)

Description

Requests an image based on different policies.

Required permissions: ohos.permission.READ_IMAGEVIDEO

Since: 12

Parameters

|Parameter|Description| |–|–| |OH_MediaAssetManager* manager|Pointer to the OH_MediaAssetManager instance.| |OH_MediaAsset* mediaAsset|Pointer to the OH_MediaAsset instance to be requested.| |MediaLibrary_RequestOptions requestOptions|Options related to the media asset quality and delivery mode. The options are specified by MediaLibrary_RequestOptions.| |MediaLibrary_RequestId* requestId|Request ID, which is specified by MediaLibrary_RequestId.| |OH_MediaLibrary_OnImageDataPrepared callback|Callback to be invoked when the requested image is ready. The callback is specified by OH_MediaLibrary_OnImageDataPrepared.|

Return value

|Type|Description| |–|–| |MediaLibrary_ErrorCode|MEDIA_LIBRARY_OK: operation success.
MEDIA_LIBRARY_PARAMETER_ERROR: incorrect parameters. Possible causes:
1. A mandatory parameter is not specified.
2. A parameter type is incorrect.
3. Parameter verification fails.
MEDIA_LIBRARY_OPERATION_NOT_SUPPORTED: unsupported operation.
MEDIA_LIBRARY_PERMISSION_DENIED: no access permission.
MEDIA_LIBRARY_INTERNAL_SYSTEM_ERROR: internal system error.|

OH_MediaAssetManager_Release()

MediaLibrary_ErrorCode OH_MediaAssetManager_Release(OH_MediaAssetManager* manager)

Description

Releases an OH_MediaAssetManager instance.

Since: 13

Parameters

|Parameter|Description| |–|–| |OH_MediaAssetManager* manager|Pointer to the OH_MediaAssetManager instance.|

Return value

|Type|Description| |–|–| |MediaLibrary_ErrorCode|MEDIA_LIBRARY_OK: operation success.
MEDIA_LIBRARY_PARAMETER_ERROR: incorrect parameters. Possible causes:
1. A mandatory parameter is not specified.
2. A parameter type is incorrect.
3. Parameter verification fails.|

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