Philips pcvc720k ユーザーズマニュアル

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10 Glossary 
 
Audio input device (recording device) 
One of the Windows multimedia settings is the recording device setting. This setting determines 
which audio hardware is being used to provide audio signals to audio applications. This setting is 
accessible through: the Windows 'Start' menu, Settings, Control Panel, MultiMedia, Audio tab. In 
the recording section, the USB digital camera microphone should be selected. (This selection will 
only be available if the camera is connected to a USB port.) 
 
AVI 
The Microsoft standard file format for combined video and sound files on the PC. This is part of 
the Video for Windows standard. 
 
BMP / JPG / TIFF / FlashPix 
These are various file formats for images. BMP files are the largest since they do not use 
compression and retain full image quality. JPG uses 'lossy' compression which dramatically 
reduces file size but the original image quality can never be restored. TIFF can use a 'lossless' 
compression algorithm with less file size reduction but retaining full image quality. FlashPix is a 
relatively new image format that uses minimal resolution within the application to speed up the 
image processing. All accepted changes are processed afterwards, before writing to disk. 
 
Codec (COding & DECoding) 
This refers to a compression format for creating sound and video streams on the computer. 
 
Compression 
Term used to describe a process of compacting or squeezing video and sound information into a 
smaller than normal size. For example, 2 to 1 compression would indicate that 2 pixels would now 
only occupy the space of 1 pixel. 
 
DirectX 
The latest standard developed primarily by Microsoft to help establish a common method for 
exchanging audio and video information between your hardware and software in the PC. 
 
Frame 
A single image in a video stream. 
 
Frame Rate 
Typically quoted in seconds (fps, frames per second), this refers to the number of single images 
that will be displayed or captured in a video stream. 
 
Gamma Correction 
The characteristics of displays which use phosphors (such as computer monitors with cathode 
ray tubes) are nonlinear. Nonlinear characteristics means that a small change in voltage when the 
voltage level is low produces a change in the output display brightness level, but this same small 
change in voltage at a high voltage level will not produce the same magnitude of change in the 
brightness output. This effect is known as gamma. Computers like to process with linear RGB 
data. Before being displayed, this linear RGB data will be processed (gamma corrected) to 
compensate for the gamma of the display. 
 
10 Glossary
 
 
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