VFW v1.1 DK "ICM_DRAW_START_PLAY" Message
Article ID: 115763
Article Last Modified on 11/12/1999
APPLIES TO
- Microsoft Video for Windows Development Kit 1.1
This article was previously published under Q115763
SUMMARY
The ICM_DRAW_START_PLAY and ICM_DRAW_STOP_PLAY messages are not
documented in the "Programmer's Guide" included in the "Video for
Windows Development Kit, version 1.1" (VFW 1.1 DK).
This article describes these messages in detail for the purpose
of assisting a developer in writing a render driver.
MORE INFORMATION
The Installable Compression Manager (ICM) communicates with a
renderer (also known as a render driver) by sending messages to it.
The renderer interprets the message and responds accordingly.
The ICM_DRAW_START_PLAY message is sent either by the ICM or by an
application that calls the ICDrawStartPlay() command. This message is sent
to tell the driver the actual starting and ending times of a play
operation. This message is sent to the driver before any frame data is
sent.
ICM_DRAW_START_PLAY is sent with two DWORD parameters, dwParam1 (the
starting time) and dwParam2 (the ending time). These times are typically
interpreted as frame numbers.
If the ending time is less than the starting time (dwParam2 < dwParam1),
then the segment plays backward.
The ICM_DRAW_STOP_PLAY message is sent when the ICDrawStopPlay() command
is issued to indicate a play operation is over. dwParam1 and dwParam2
are not used with this message and should be ignored by the driver.
Additional query words: 1.10
Keywords: kb16bitonly KB115763