Philips PC Camera User Manual page 20

Q: The video works, but no audio is recorded: My application doesn't produce any audio.
A: There are several reasons for not having audio:
1.
The camera microphone can only produce a mono audio signal. Check whether the
application uses this setting. If not, adjust the audio setting to mono.
2.
Check whether the USB PC camera microphone is selected as the current recording
device. (Start, Settings, Control Panel, MultiMedia, Audio tab. In the recording section,
the 'Philips VGA Digital camera, Audio (Microphone)' should be selected).
3.
Check whether 'Mute' has been switched on (see Camera Settings - Audio). If so, switch
it off.
Q: No audio (USB timer outside specification)
A: If you hear no audio, and have tried every troubleshooting tip in the user guide and the on-line
help to no avail, the USB hardware in your computer may be the cause of the problem. In most
cases it will be the USB timer clock that is not stable enough for streaming audio applications.
Q: System lockup: My camera stops responding (black or frozen picture or LED off) for no
obvious reason.
A: Switch off the Hardware Accelerator for your video card (click on: My computer, right mouse
button, Properties, Performance tab, Graphics button, Set 'Hardware Acceleration' to 'None').
Contact your video display card manufacturer to obtain the latest video card drivers. See the
video display card's documentation for more information.
Q: Picture Flicker: My video picture is flickering.
A: This may happen in office environments with 50 or 60 Hz fluorescent lighting when certain
frame rates are used. There are two solutions:
1.
Select the 'Flickerless' option. This option is located in the 'Image Controls' property
page. This property page is accessible from within the application you are using.
2.
Deselect the 'Flickerless' option. The frame rates '5', '10' and '20' are always flickerless in
50 Hz lighting environments. Only the frame rates 15, 25 and 30 are affected by the
electronic 'Flickerless' control.
Q: 'Unable to draw this data format': The message 'Unable to draw this data format'
appears.
A: This can happen when the selected data stream format could not be processed due to a
missing codec. Re-install the camera driver software to install the missing codec.
Q: Why are frames dropped during the recording of a streaming video?
A: If a video clip is created at a high resolution such as VGA and high frame rate, a tremendous
amount of data is generated. For example, the amount of video data generated using VGA
resolution at 30 fps with 24 bit full colour is 640x480x30x24 = 221,184,000 bits (221 Mbit) or
27.65 Mbyte per second. Audio adds even more data on top of this. Hardly any computer system
and/or hard drive is capable of handling this kind of data stream. The result is that a number of
frames are dropped in order to match the data stream with the capabilities of your computer. This
effect can be reduced or completely eliminated by applying the following measures:
1.
changing to a lower resolution such as 320x240 or lower
2.
changing to a lower frame rate
3.
putting the hard drive in DMA mode
4.
using a new file instead of overwriting an existing one
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