a logo can be any artwork that is formatted as a 24-bit bmp file. typically, a logo is a small graphic that is placed at the lower left of the image. in a technical application, however, a logo could be a crosshair pattern placed at the center of the image. the logo can theoretically be any size. however, the cpu must actively draw the image on every frame of video, and drawing a very large image, even if it is mostly transparent, degrades overall performance in high-throughput applications.

    the driver can draw a logo on captured or streaming video, on preview video, or on dibdraw overlays. however, the driver cannot draw a logo on directdraw overlays. if you attempt to draw a logo on directdraw overlays, everything appears to work fine, except that the logo is not visible.

    a logo’s rectangle can be partially transparent so that the underlying video is visible. the transparent areas are defined by a key color - a particular (red, green, blue) value that is specially interpreted by the driver. for example, the sample logos use cyan with red, green and blue values of (0, 128, 128) as the key color.

    a logo displays in either of two styles - normal and embossed. in normal style, the logo’s non-transparent pixels simply replace whatever video underlies it. in embossed or translucent style, the logo's non-transparent pixels are averaged with the underlying video pixels, resulting in a more subtle effect.

    for detailed instructions on setting up a logo, review the following steps:

    step 0 - before you start

    step 1 - creating and enabling the logo

    step 2 - selecting the logo file

    step 3 - setting key color and style

    step 4 - positioning the logo

    step 5 - reviewing and saving the changes