1e41f4b71Sopenharmony_ci# PreviewOutput_Callbacks 2e41f4b71Sopenharmony_ci 3e41f4b71Sopenharmony_ci 4e41f4b71Sopenharmony_ci## Overview 5e41f4b71Sopenharmony_ci 6e41f4b71Sopenharmony_ciThe PreviewOutput_Callbacks struct describes the callbacks related to preview output. 7e41f4b71Sopenharmony_ci 8e41f4b71Sopenharmony_ciFor details, see [OH_PreviewOutput_RegisterCallback](_o_h___camera.md#oh_previewoutput_registercallback). 9e41f4b71Sopenharmony_ci 10e41f4b71Sopenharmony_ci**Since**: 11 11e41f4b71Sopenharmony_ci 12e41f4b71Sopenharmony_ci**Related module**: [OH_Camera](_o_h___camera.md) 13e41f4b71Sopenharmony_ci 14e41f4b71Sopenharmony_ci 15e41f4b71Sopenharmony_ci## Summary 16e41f4b71Sopenharmony_ci 17e41f4b71Sopenharmony_ci 18e41f4b71Sopenharmony_ci### Member Variables 19e41f4b71Sopenharmony_ci 20e41f4b71Sopenharmony_ci| Name| Description| 21e41f4b71Sopenharmony_ci| -------- | -------- | 22e41f4b71Sopenharmony_ci| [OH_PreviewOutput_OnFrameStart](_o_h___camera.md#oh_previewoutput_onframestart) [onFrameStart](#onframestart) | Callback to report preview output frame start events.| 23e41f4b71Sopenharmony_ci| [OH_PreviewOutput_OnFrameEnd](_o_h___camera.md#oh_previewoutput_onframeend) [onFrameEnd](#onframeend) | Callback to report preview output frame end events.| 24e41f4b71Sopenharmony_ci| [OH_PreviewOutput_OnError](_o_h___camera.md#oh_previewoutput_onerror) [onError](#onerror) | Callback to report preview output errors.| 25e41f4b71Sopenharmony_ci 26e41f4b71Sopenharmony_ci 27e41f4b71Sopenharmony_ci## Member Variable Description 28e41f4b71Sopenharmony_ci 29e41f4b71Sopenharmony_ci 30e41f4b71Sopenharmony_ci### onError 31e41f4b71Sopenharmony_ci 32e41f4b71Sopenharmony_ci``` 33e41f4b71Sopenharmony_ciOH_PreviewOutput_OnError PreviewOutput_Callbacks::onError 34e41f4b71Sopenharmony_ci``` 35e41f4b71Sopenharmony_ci 36e41f4b71Sopenharmony_ci**Description** 37e41f4b71Sopenharmony_ci 38e41f4b71Sopenharmony_ciCallback to report preview output errors. 39e41f4b71Sopenharmony_ci 40e41f4b71Sopenharmony_ci 41e41f4b71Sopenharmony_ci### onFrameEnd 42e41f4b71Sopenharmony_ci 43e41f4b71Sopenharmony_ci``` 44e41f4b71Sopenharmony_ciOH_PreviewOutput_OnFrameEnd PreviewOutput_Callbacks::onFrameEnd 45e41f4b71Sopenharmony_ci``` 46e41f4b71Sopenharmony_ci 47e41f4b71Sopenharmony_ci**Description** 48e41f4b71Sopenharmony_ci 49e41f4b71Sopenharmony_ciCallback to report preview output frame end events. 50e41f4b71Sopenharmony_ci 51e41f4b71Sopenharmony_ci 52e41f4b71Sopenharmony_ci### onFrameStart 53e41f4b71Sopenharmony_ci 54e41f4b71Sopenharmony_ci``` 55e41f4b71Sopenharmony_ciOH_PreviewOutput_OnFrameStart PreviewOutput_Callbacks::onFrameStart 56e41f4b71Sopenharmony_ci``` 57e41f4b71Sopenharmony_ci 58e41f4b71Sopenharmony_ci**Description** 59e41f4b71Sopenharmony_ci 60e41f4b71Sopenharmony_ciCallback to report preview output frame start events. 61