IWiaVideo interface (wiavideo.h)
The IWiaVideo interface provides methods that allow an application that uses Windows Image Acquisition (WIA) services to acquire still images from a streaming video device.
Note WIA does not support video devices in Windows Server 2003, Windows Vista, and later. For those versions of the Windows, use DirectShow to acquire images from video.
Inheritance
The IWiaVideo interface inherits from the IUnknown interface. IWiaVideo also has these types of members:
Methods
The IWiaVideo interface has these methods.
| IWiaVideo::CreateVideoByDevNum The IWiaVideo::CreateVideoByDevNum method creates a connection to a streaming video device with the device number obtained from a Directshow enumeration. |
| IWiaVideo::CreateVideoByName The IWiaVideo::CreateVideoByName method creates a connection to a streaming video device with the friendly device name obtained from a Directshow enumeration. |
| IWiaVideo::CreateVideoByWiaDevID The IWiaVideo::CreateVideoByWiaDevID method creates a connection to a streaming video device from its WIA_DIP_DEV_ID property. |
| IWiaVideo::DestroyVideo The IWiaVideo::DestroyVideo method shuts down the streaming video. To restart video playback, the application must call one of the IWiaVideo CreateVideo methods again. |
| IWiaVideo::get_ImagesDirectory The IWiaVideo::ImagesDirectory property specifies the full path and directory where images are stored when calling the IWiaVideo::TakePicture method. (Get) |
| IWiaVideo::get_PreviewVisible The IWiaVideo::PreviewVisible property specifies whether the video playback is visible in its parent window. This does not affect the WIAVIDEO_STATE of the video. (Get) |
| IWiaVideo::GetCurrentState The IWiaVideo::GetCurrentState method specifies the state of the video stream as a member of the WIAVIDEO_STATE enumeration. |
| IWiaVideo::Pause The IWiaVideo::Pause method pauses video playback. |
| IWiaVideo::Play Begins playback of streaming video. |
| IWiaVideo::put_ImagesDirectory The IWiaVideo::ImagesDirectory property specifies the full path and directory where images are stored when calling the IWiaVideo::TakePicture method. (Put) |
| IWiaVideo::put_PreviewVisible The IWiaVideo::PreviewVisible property specifies whether the video playback is visible in its parent window. This does not affect the WIAVIDEO_STATE of the video. (Put) |
| IWiaVideo::ResizeVideo The IWiaVideo::ResizeVideo method resizes the video playback to the largest supported resolution that fits inside the parent window. Call this method whenever the parent window is moved or resized. |
| IWiaVideo::TakePicture The IWiaVideo::TakePicture method extracts a still image from the video stream, and saves the image as a JPEG file. |
Remarks
The IWiaVideo interface, like all Component Object Model (COM) interfaces, inherits the IUnknown interface methods.
| IUnknown Methods | Description |
|---|---|
| IUnknown::QueryInterface | Returns pointers to supported interfaces. |
| IUnknown::AddRef | Increments reference count. |
| IUnknown::Release | Decrements reference count. |
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows XP [desktop apps only] |
| Minimum supported server | Windows Server 2003 [desktop apps only] |
| Target Platform | Windows |
| Header | wiavideo.h |