1# OH_AVCodecCallback 2 3## Overview 4 5The struct defines all the asynchronous callback function pointers of an OH_AVCodec instance. To ensure the normal running of OH_AVCodec, you must register the instance of this struct with the OH_AVCodec instance and process the information reported by the callback function. 6 7For details about the development guide, see step 4 in surface mode or step 3 in buffer mode in [Video Encoding](../../media/avcodec/video-encoding.md). 8 9**Since**: 11 10 11**Related module**: [CodecBase](capi-codecbase.md) 12 13**Header file**: [native_avcodec_base.h](capi-native-avcodec-base-h.md) 14 15## Summary 16 17### Member Variables 18 19| Name| Description| 20| -- | -- | 21| [OH_AVCodecOnError](capi-native-avcodec-base-h.md#oh_avcodeconerror) onError | Callback used to report a codec operation error.| 22| [OH_AVCodecOnStreamChanged](capi-native-avcodec-base-h.md#oh_avcodeconstreamchanged) onStreamChanged | Callback used to report a codec stream change.| 23| [OH_AVCodecOnNeedInputBuffer](capi-native-avcodec-base-h.md#oh_avcodeconneedinputbuffer) onNeedInputBuffer| Callback used to report input data required.| 24| [OH_AVCodecOnNewOutputBuffer](capi-native-avcodec-base-h.md#oh_avcodeconnewoutputbuffer) onNewOutputBuffer | Callback used to report output data generated.| 25