PRELIMINARY
TV SCALER
S3C6400X RISC MICROPROCESSOR
16-8
Preliminary product information describe products that are in development,
for which full characterization data and associated errata are not yet available.
Specifications and information herein are subject to change without notice.
As explained in the previous section, SRC_Width and DST_Width satisfies the word boundary constraints such
that the number of horizontal pixel can be represented by kn where n = 1,2,3, … and k = 1 / 2 / 8 for 24bppRGB /
16bppRGB / YCbCr420 image, respectively. Also SRC_Width must be 4’s multiple of PreScale_H_Ratio and
SRC_Height must be multiple of PreScale_V_Ratio.
Figure 16-5 Source destination image size Block Diagram
The other control registers of pre-scaled image size, pre-scale ratio, pre-scale shift ratio and main scale ratio
are defined according to the following equations.
If ( SRC_Width >= 64 × DST_Width ) { Exit(-1); /* Out Of Horizontal Scale Range */ }
else if (SRC_Width >= 32 × DST_Width) { PreScale_H_Ratio = 32; H_Shift = 5; }
else if (SRC_Width >= 16 × DST_Width) { PreScale_H_Ratio = 16; H_Shift = 4; }
else if (SRC_Width >= 8 × DST_Width) { PreScale_H_Ratio = 8; H_Shift = 3; }
else if (SRC_Width >= 4 × DST_Width) { PreScale_H_Ratio = 4; H_Shift = 2; }
else if (SRC_Width >= 2 × DST_Width) { PreScale_H_Ratio = 2; H_Shift = 1; }
else { PreScale_H_Ratio = 1; H_Shift = 0; }
PreScale_DSTWidth = SRC_Width / PreScale_H_Ratio;
dx = ( SRC_Width << 8 ) / ( DST_Width << H_Shift);
If ( SRC_Height >= 64 × DST_Height ) { Exit(-1); /* Out Of Vertical Scale Range */ }
Source Image Destination
Image
SRC_Width
0
1
1
SRC
H
i
h
DST_Width
DST_
Heigh
t
서식
번호