MCIWnd
Window User Interface
MCIWnd
provides additional features to adjust the look of the MCIWnd window, customize
the behavior of your application, and tune playback performance. The following
features are included in the MCIWnd window:
A toolbar with Play, Stop,
Record and Menu buttons
A trackbar that controls
positioning within the playback content
A pop-up menu containing common
commands
A playback area for video and
other devices that display images
The following
illustration shows the initial state of user-controlled video playback. The
sample file used is CLOCK.AVI.
{bmc bm83.BMP}
The MCIWnd
window includes a playback area for video and other devices that display images
during playback. MCIWnd omits the playback area from waveform-audio devices,
MIDI sequencers, and other devices that do not write to the display. The
following illustration shows the waveform-audio playback area.
{bmc bm84.BMP}
The Play
button is located in the lower-left corner of the MCIWnd window. It appears
when the content is stopped. The user can play the content in the following
ways:
To play the content from the
current playback position, select the Play button.
To play the content full-screen
from the current playback position, select the Play button while holding
down the CTRL key.
To play the content backward
from the current playback position, select the Play button while holding
down the SHIFT key.
The Menu
button, located next to the Play button, activates a menu that allows
the user to open and close audio-video interleaved (AVI) files, and to adjust
the image size, playback speed, and volume. (The user can also activate the menu
by clicking the right mouse button whenever the cursor is in the client area of
the window.) The menu also includes commands to change the configuration of the
current device, to copy the playback content to the clipboard, and to issue MCI
commands.
The trackbar
to the right of the Menu button represents the duration of the playback
(or recorded) content. The slider on the trackbar represents the current
playback position within the content. When the slider is positioned at the left
end of the trackbar, the current playback position is the beginning of the
content. The user can move to different locations in the content by dragging
the slider along the trackbar. The Stop button is located in the
lower-left corner of the MCIWnd window. It appears when the content is played.
The following illustration shows video playback in progress.
{bmc bm85.BMP}
The MCIWnd controls
can also include a Record button for devices that can record. The Record
button is marked with a red circle and appears only when the device is capable
of recording.
Note The playback
window must be aligned on a four-pixel boundary for the best video playback
performance. Typically, the Microsoft Windows operating system aligns the window automatically when
it is created. If a user moves or stretches the window from its initial
position, video playback speed might be reduced by half.