1# PreviewOutput_Callbacks 2 3 4## Overview 5 6The PreviewOutput_Callbacks struct describes the callbacks related to preview output. 7 8For details, see [OH_PreviewOutput_RegisterCallback](_o_h___camera.md#oh_previewoutput_registercallback). 9 10**Since**: 11 11 12**Related module**: [OH_Camera](_o_h___camera.md) 13 14 15## Summary 16 17 18### Member Variables 19 20| Name| Description| 21| -------- | -------- | 22| [OH_PreviewOutput_OnFrameStart](_o_h___camera.md#oh_previewoutput_onframestart) [onFrameStart](#onframestart) | Callback to report preview output frame start events.| 23| [OH_PreviewOutput_OnFrameEnd](_o_h___camera.md#oh_previewoutput_onframeend) [onFrameEnd](#onframeend) | Callback to report preview output frame end events.| 24| [OH_PreviewOutput_OnError](_o_h___camera.md#oh_previewoutput_onerror) [onError](#onerror) | Callback to report preview output errors.| 25 26 27## Member Variable Description 28 29 30### onError 31 32``` 33OH_PreviewOutput_OnError PreviewOutput_Callbacks::onError 34``` 35 36**Description** 37 38Callback to report preview output errors. 39 40 41### onFrameEnd 42 43``` 44OH_PreviewOutput_OnFrameEnd PreviewOutput_Callbacks::onFrameEnd 45``` 46 47**Description** 48 49Callback to report preview output frame end events. 50 51 52### onFrameStart 53 54``` 55OH_PreviewOutput_OnFrameStart PreviewOutput_Callbacks::onFrameStart 56``` 57 58**Description** 59 60Callback to report preview output frame start events. 61