2.5.1 Scaling Filter
The gmZAN1 scaling filter uses an advanced adaptive scaling technique proprietary to Genesis Microchip Inc. and provides high quality scaling of real time video and graphics images. This is Genesis’ third generation scaling technology that benefits from the expertise and feedback gained by supporting a wide range of solutions and applications.
2.5.2 Gamma Table
The gamma table is used to adjust the RGB data for the individual display characteristics of the TFT panel. The overall gamma of the display may be set, as well as separate corrections for each of the three display channels. In addition, the gamma table may be used for contrast, brightness, and white balance (temperature) adjustments. The lookup table has an
2.5.3 RGB Offset
The RGB offsets provide a simple shift (positive or negative) for each of the three color channels. This may be used as a simple brightness adjustment within a limited range. The data is clamped to zero for negative offsets, and clamped to FFh for positive offsets. This adjustment is much faster than recalculating the gamma table, and could be used with the OSD user controller to provide a quick brightness adjust. An offset range of plus 127*4 to minus 127*4 is available.
2.5.4 Panel Data Dither
For TFT panels that have fewer than eight bits for each R,G,B input, the gmZAN1 provides ordered and random dithering patterns to help smoothly shade colors on
2.5.5 Panel Background Color
A solid background color may be selected for a border around the active display area. The background color is most often set to black.
2.6 Panel Interface
The gmZAN1 chip interfaces directly with all of today’s commonly used active matrix flat panels with 640x480, 800x600 and 1024x768 resolutions. The resolution and the aspect ratio are NOT limited to specific values.
2.6.1 TFT Panel Interface Timing Specification
The TFT panel interface timing parameters are listed in Table 13 below. Refer to three timing diagrams of Figure 7 and Figure 8 for the timing parameter definition. All aspects of the gmZAN1 interface are programmable. For horizontal parameters, Horizontal Display Enable Start, Horizontal Display Enable End, Horizontal Sync Start and Horizontal Sync End are programmable. Vertical Display Enable Start, Vertical Display Enable End, Vertical Sync Start and Vertical Sync End are also fully programmable.
In order to maximize panel data setup and hold time, the panel clock (PCLKA, PCLKB) output skew is programmable. In addition, the current drive strength of the panel interface pins is programmable.
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