Ngoài các thiết kế hệ điều hành dành cho máy tính desktop và máy chủ (server), các nhà cung cấp hệ điều hành linux còn thiết kế ra các bản chuyên biệt cho các mục đích khác nhau như: hỗ trợ kiến trúc máy tính, hệ thống nhúng (embedded Linux system), các hệ thống bảo mật, an ninh mạng | 148 Part III Entertaining Your Brain with a Little Help from Linux 3. To adjust Brightness Contrast Gamma and Saturation click the Video Controls tab and fiddle with the sliders there. Gamma is a curve that depicts how light or dark the gray tones of an image appear. Saturation is a measure of the intensity of a hue. A highly saturated image has bright colors and an image low in saturation is gray with almost no color. Brightness defines the amount of white in an image. Contrast defines how light the light tones are and how dark the dark tones are. 4. If you have more than one webcam or TV Tuner card connected to your computer you can click the Tuning tab and choose the webcam or tuner that you want to view. 5. If your camera is a Philips camera as are a variety of popular Logitech cameras you can click the Philips Extensions tab to adjust the lighting noise reduction and compression of your image. Sending ụour webcam images to other computers CamStream generates a series of still images at speeds that you specify and saves them either on your computer s hard drive or sends them via FTP to the hard drive of another computer that you specify. To send your files to be seen on another computer follow these steps 1. Click the Configuration button in the CamStream window. Refer to Figure 8-3. The Snapshot Settings window appears. 2. Select the radio button for the file format that you desire such as JPEG PNG PPM or BMP and then type the name of the file into the Basename text box. 3. If you desire you can select any of these three options Re-Use Filename Overwrite Select this radio button so that every time an image is created it overwrites the image with the same filename. Put Timestamp in Filename Selecting this radio button makes the time and date part of the filename of each new image. Number Sequentially Select this radio button and each image will be numbered in sequence. Chapter 8 Having Fun with a Webcam 149 4. Type a number in the Maximum Sequence Number text .
