1# avmetadata_extractor.h 2 3 4## Overview 5 6The **avmetadata_extractor.h** file declares the AVMetadataExtractor APIs. With these native APIs, you can obtain metadata from media assets. 7 8**System capability**: SystemCapability.Multimedia.Media.AVMetadataExtractor 9 10**Library**: libavmetadata_extractor.so 11 12**Since**: 18 13 14**Related module**: [AVMetadataExtractor](_a_v_metadata_extractor.md) 15 16 17## Summary 18 19 20### Types 21 22| Name| Description| 23| -------- | -------- | 24| typedef struct [OH_AVMetadataExtractor](_a_v_metadata_extractor.md#oh_avmetadataextractor) [OH_AVMetadataExtractor](_a_v_metadata_extractor.md#oh_avmetadataextractor) | Defines a struct for the OH_AVMetadataExtractor. | 25 26 27### Functions 28 29| Name| Description| 30| -------- | -------- | 31| [OH_AVMetadataExtractor](_a_v_metadata_extractor.md#oh_avmetadataextractor) \* [OH_AVMetadataExtractor_Create](_a_v_metadata_extractor.md#oh_avmetadataextractor_create) (void) | Creates an **OH_AVMetadataExtractor** instance. | 32| [OH_AVErrCode](../apis-avcodec-kit/_core.md#oh_averrcode) [OH_AVMetadataExtractor_SetFDSource](_a_v_metadata_extractor.md#oh_avmetadataextractor_setfdsource) ([OH_AVMetadataExtractor](_a_v_metadata_extractor.md#oh_avmetadataextractor) \*extractor, int32_t fd, int64_t offset, int64_t size) | Sets a data source based on the media file descriptor. | 33| [OH_AVErrCode](../apis-avcodec-kit/_core.md#oh_averrcode) [OH_AVMetadataExtractor_FetchMetadata](_a_v_metadata_extractor.md#oh_avmetadataextractor_fetchmetadata) ([OH_AVMetadataExtractor](_a_v_metadata_extractor.md#oh_avmetadataextractor) \*extractor, OH_AVFormat \*avMetadata) | Obtains metadata from a media asset. This function must be called after [SetFDSource](_a_v_metadata_extractor.md#oh_avmetadataextractor_setfdsource).| 34| [OH_AVErrCode](../apis-avcodec-kit/_core.md#oh_averrcode) [OH_AVMetadataExtractor_FetchAlbumCover](_a_v_metadata_extractor.md#oh_avmetadataextractor_fetchalbumcover) ([OH_AVMetadataExtractor](_a_v_metadata_extractor.md#oh_avmetadataextractor) \*extractor, OH_PixelmapNative \*\*pixelMap) | Obtains the cover of an audio album. This function must be called after [SetFDSource](_a_v_metadata_extractor.md#oh_avmetadataextractor_setfdsource).| 35| [OH_AVErrCode](../apis-avcodec-kit/_core.md#oh_averrcode) [OH_AVMetadataExtractor_Release](_a_v_metadata_extractor.md#oh_avmetadataextractor_release) ([OH_AVMetadataExtractor](_a_v_metadata_extractor.md#oh_avmetadataextractor) \*extractor) | Releases the resources used by the **OH_AVMetadataExtractor** instance and destroys the instance. | 36