ACM_PLAY message

Plays an AVI clip in an animation control. The control plays the clip in the background while the thread continues executing. You can send this message explicitly or by using the Animate_Play macro.

wParam

A UINT that specifies the number of times to replay the AVI clip. A value of -1 means replay the clip indefinitely.

lParam

The LOWORD is the zero-based index of the frame where playing begins. The value must be less than 65,536. A value of zero means begin with the first frame in the AVI clip.

The HIWORD is the zero-based index of the frame where playing ends. The value must be less than 65,536. A value of -1 means end with the last frame in the AVI clip.

Returns nonzero if successful, or zero otherwise.

You can use Animate_Seek to direct the animation control to display a particular frame of the AVI clip.