Graphics Files - Ultech Corporation DV2000 User Manual

32 ULTECH DV2000 User's Manual

5.4 Graphics Files

DV2000 displays bit mapped graphics files in a format known as "YCrCb". YCrCb is the
component video format inherent in serial digital video. ULTECH created a YCrCb file
format known as "YC" format. Section 5.5 provides details about this file format. Software
developers may choose to produce graphics files directly in YC format. Other DV2000 users
may create files in several industry formats, then convert them to YC format. A future
version of DV2000 software will convert all of the popular formats to YC format as the files
are transferred to the DV2000. The current version of software requires a separate conver-
sion step on a PC using graphics file converters supplied by ULTECH. ULTECH provides a
Microsoft Windows program that lets you view YC files on a PC without requiring DV2000
hardware.
Graphics Files Supported
All of the files described in this section are comprised of Red, Green, and Blue color compo-
nents ("RGB"). Combinations of RGB are mixed to produce all of the colors possible on a
TV screen. The 8 bit RGB formats—the formats where RGB can each be 1 of 256 possible
values—produce over 16 million colors. Not all can be conveyed with serial digital compo-
nent video, though, as component video yields a color space that is a subset of RGB colors
(11,137,500 colors out of 16,777,216).
Some of the formats below employ an "alpha" channel in addition to RGB channels. An
alpha channel specifies transparency. Each pixel is made up of a Red, Green, and Blue
component. Plus, there is an alpha component that specifies the opacity of the pixel. An
alpha value of "0" means the pixel is transparent: only background video is seen. An alpha
value of "256" means the pixel is 100% opaque. Values in between allow background video
to mix with foreground text/graphics. The DV2000 provides an 8 bit alpha capability. Use of
an alpha gradient between foreground images and background video is one of the secrets for
producing perfect images on screen.
BMP Version 4
This is Microsoft's BMP format released for Windows 95, and is a 32 bit format containing
8 bits each of red, green, and blue, plus an 8 bit alpha channel. ULTECH supports the non-
compressed, 32 bits per pixel version of this format. Use the file converter "BMP.EXE" to
convert these files to ULTECH's "YC" format.
PCX
PCX, also known as PC Paintbrush Format, is a popular graphics file format. PCX does not
provide an alpha channel. ULTECH supports the 24 bit format. Use the file converter
"PCX.EXE" to convert these files to ULTECH's "YC" format. Because PCX does not
support alpha, the converter generates a fully opaque image in YC format.