Public Version
Camera ISP Functional Description
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For (i=0; i<output_width; i++) { /* output width depends of input width and resizing factors*/
Coarse-input pointer = (fine-input p 32) >> 5
/* Round to nearest phase */
Pixel-input pointer = (coarse-input pointer >> 2) + 1
/* Round up to a whole pixel */
Coefficient phase = pixel-input pointer & 3
/* 2 LSB = phase */
if (i & 1 == 0) { /* Even output pixel, generate YCbCr
*/
Yout = dot product of the 7 coefficients and the 7 Y inputs starting with pixel-input pointer
Cbout = dot product of the 7 coefficients and the 7 upsampled Cb inputs starting with
pixel-input pointer
Crout = dot product of the 7 coefficients and the 7 upsampled Cr inputs starting with
pixel-input pointer
Clip outputs to 8-bit unsigned for luma, 8-bit
signed for chroma
}
Else {/* Odd output pixel, generate Y only */
Yout = dot product of the 7 coefficients and the 7 Y inputs starting with pixel-input pointer
Clip output to 8-bit unsigned
}
Fine-input pointer = fine-input p (
[9:0] HRSZ + 1)
}
}
NOTE:
The chroma input values are internally replicated to realize 1:2 upsampling to line up with
luma input values. Only required chroma outputs are computed; they correspond to even
luma outputs.
Bilinear Interpolation (4-Tap or 7-Tap):
For the bilinear interpolation flow of chroma horizontal resizing, the algorithm is adapted as follows. For
the bilinear interpolation option, it is not necessary to replicate chroma samples.
For (i=0; i<output_width; i++) {
if (i & 1 == 0) { /* even output pixel, generate YCbCr */
Coarse-input pointer = ... /*Calculation issued from 4 taps or 7
taps*/
Pixel-input pointer = ... /*Calculation issued from 4 taps or 7 taps*/
Yout = dot product of ... /*Calculation issued from 4 taps or 7
taps*/
C_fine_input_pointer = fine_input_p 128*ntaps
/* Points to center of filter
kernel */
Cidx = C_fine_input_pointer >> 9
/* Truncate to even pixel
grid to find left value */
Cbin[0] = Cb[Cidx]
Cbin[1] = Cb[Cidx + 1]
Crin[0] = Cr[Cidx]
Crin[1] = Cr[Cidx + 1]
frac = C_fine_input_pointer & 511
/* 9-bit fraction */
Cbout = ((512 - frac) * Cbin[0] + frac * Cbin[1] + 256) >> 9
Crout = ((512 - frac) * Crin[0] + frac * Crin[1] + 256) >> 9
1222
Camera Image Signal Processor
SWPU177N – December 2009 – Revised November 2010
Copyright © 2009–2010, Texas Instruments Incorporated
Содержание OMAP36 Series
Страница 174: ...174 List of Tables SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 692: ...692 MPU Subsystem SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 1084: ...1084 IVA2 2 Subsystem SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 1990: ...1990 2D 3D Graphics Accelerator SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 2334: ...2334 Memory Subsystem SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 2700: ...2700 Memory Management Units SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 2868: ...2868 HDQ 1 Wire SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 2974: ...2974 UART IrDA CIR SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 3054: ...3054 Multichannel SPI SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 3462: ...3462 MMC SD SDIO Card Interface SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 3508: ...3508 General Purpose Interface SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 3584: ...3584 Initialization SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...
Страница 3648: ...3648 Debug and Emulation SWPU177N December 2009 Revised November 2010 Copyright 2009 2010 Texas Instruments Incorporated ...