The capture rate is the number of frames that are captured each second of a capture session. You can retrieve the current capture rate by using the WM_CAP_GET_SEQUENCE_SETUP message (or the capCaptureGetSetup macro). The current capture rate is stored in the dwRequestMicroSecPerFrame member of the CAPTUREPARMS structure. You can set the capture rate by specifying the number of microseconds between successive frames as the value of this member, then sending the updated CAPTUREPARMS structure to the capture window by using the WM_CAP_SET_SEQUENCE_SETUP message (or the capCaptureSetSetup macro). The default value of dwRequestMicroSecPerFrame is 66667, which corresponds to 15 frames per second.