b320bbaf61
Optimizes YUV to RGB conversion using ARMv5 multiply-accumulate
intructions for operations and data tables for saturation.
This first patch set includes the three versions i have developed.
Although iPod Classic need to use the latest version to reach 30fps,
old versions may serve other targets.
All versions are based on current SVN algorithm (round->scale->add)
using the same coefficients, so output results are identical.
Version history:
ARMv4:
- use all available registers to calculate four pixels within each
loop iteration.
- avoid LDR interlocks.
ARMv5TE:
- use ARMv5TE+ 1-cycle multiply-accumulate instructions.
ARMv5TE_WST:
- use data tables (256 bytes) for RBG565 saturation.
Benchmarks results using iPod Classic (ARM926EJ 216Mhz):
size test_fps (1) mpegplayer (2)
bytes YUV YUV1/4 average min/max
----- ----------- ------------------
SVN-20141107 528 27.8 110.0 11035 10864/13397
ARMv4 480 28.8 114.0 9767 9586/12126
ARMv5TE 468 29.7 117.5 8751 8584/11118
ARMv5TE_WST 544 33.6 133.0 6355 6316/6403
(1) boosted
(2) play full elephants_dream_320x240.mpg file (15693 frames) using
mpegplayer, patched RB measures YUV to RGB565 frame conversion
time (microseconds)
Compared against the WST version, the ARMV5TE version w/o cached
saturation tables is slower, but it is smaller and i have doubts
about the power consumption.
Change-Id: I2b6a81804636658d85a1bb104ccb2055e77ac120
Reviewed-on: http://gerrit.rockbox.org/1034
Reviewed-by: Cástor Muñoz <cmvidal@gmail.com>
Tested: Cástor Muñoz <cmvidal@gmail.com>
1013 lines
42 KiB
ArmAsm
1013 lines
42 KiB
ArmAsm
/***************************************************************************
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* __________ __ ___.
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* Open \______ \ ____ ____ | | _\_ |__ _______ ___
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* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
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* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
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* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
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* \/ \/ \/ \/ \/
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* $Id: lcd-as-video.S 26756 2010-06-11 04:41:36Z funman $
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*
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* Copyright (C) 2010 by Andree Buschmann
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
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* KIND, either express or implied.
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*
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****************************************************************************/
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/* Version history:
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*
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* SVN:
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* - initial SVN version.
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*
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* ARMv4:
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* - use all available registers to calculate four pixels within each
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* loop iteration.
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* - avoid LDR interlocks.
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*
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* ARMv5TE:
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* - use ARMv5TE+ 1-cycle multiply-accumulate instructions.
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*
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* ARMv5TE_WST:
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* - use data tables (256 bytes) for RBG565 saturation.
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*
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* All versions are based on current SVN algorithm (round->scale->add)
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* using the same coefficients, so output results are identical.
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*
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* TODO?: SVN coefficients are a very nice approximation for operations
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* with shift+add instructions. When 16x16+32 MLA instructions are used,
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* NBR and COEF_N could probably be adjusted to slighly increase accuracy.
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*/
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#define VERSION_SVN 0
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#define VERSION_ARMV4 1
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#define VERSION_ARMV5TE 2
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#define VERSION_ARMV5TE_WST 3
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#define YUV2RGB_VERSION VERSION_ARMV5TE_WST
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#define ASM
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#include "config.h"
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#include "cpu.h"
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#if (YUV2RGB_VERSION == VERSION_SVN)
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.section .icode, "ax", %progbits
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/****************************************************************************
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* extern void lcd_write_yuv420_lines(unsigned char const * const src[3],
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* uint16_t* out,
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* int width,
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* int stride);
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*
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* Conversion from Motion JPEG and MPEG Y'PbPr to RGB is:
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* |R| |1.164 0.000 1.596| |Y' - 16|
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* |G| = |1.164 -0.391 -0.813| |Pb - 128|
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* |B| |1.164 2.018 0.000| |Pr - 128|
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*
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* Scaled, normalized, rounded and tweaked to yield RGB 565:
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* |R| |74 0 101| |Y' - 16| >> 9
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* |G| = |74 -24 -51| |Cb - 128| >> 8
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* |B| |74 128 0| |Cr - 128| >> 9
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*
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* Converts two lines from YUV to RGB565 and writes to LCD at once. First loop
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* loads Cb/Cr, calculates the chroma offset and saves them to buffer. Within
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* the second loop these chroma offset are reloaded from buffer. Within each
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* loop two pixels are calculated and written to LCD.
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*/
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.align 2
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.global lcd_write_yuv420_lines
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.type lcd_write_yuv420_lines, %function
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lcd_write_yuv420_lines:
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/* r0 = src = yuv_src */
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/* r1 = dst = out */
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/* r2 = width */
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/* r3 = stride */
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stmfd sp!, { r4-r10, lr } /* save non-scratch */
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ldmia r0, { r9, r10, r12 } /* r9 = yuv_src[0] = Y'_p */
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/* r10 = yuv_src[1] = Cb_p */
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/* r12 = yuv_src[2] = Cr_p */
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add r3, r9, r3 /* r3 = &ysrc[stride] */
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add r4, r2, r2, asr #1 /* chroma buffer lenght = width/2 *3 */
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mov r4, r4, asl #2 /* use words for str/ldm possibility */
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add r4, r4, #15 /* plus room for 3 additional words, */
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bic r4, r4, #3 /* rounded up to multiples of 4 byte */
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sub sp, sp, r4 /* and allocate on stack */
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stmia sp, {r2-r4} /* width, &ysrc[stride], stack_alloc */
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mov r7, r2 /* r7 = loop count */
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add r8, sp, #12 /* chroma buffer */
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mov lr, r1 /* RGB565 data destination buffer */
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/* 1st loop start */
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10: /* loop start */
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ldrb r0, [r10], #1 /* r0 = *usrc++ = *Cb_p++ */
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ldrb r1, [r12], #1 /* r1 = *vsrc++ = *Cr_p++ */
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sub r0, r0, #128 /* r0 = Cb-128 */
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sub r1, r1, #128 /* r1 = Cr-128 */
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add r2, r1, r1, asl #1 /* r2 = Cr*51 + Cb*24 */
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add r2, r2, r2, asl #4
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add r2, r2, r0, asl #3
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add r2, r2, r0, asl #4
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add r4, r1, r1, asl #2 /* r1 = Cr*101 */
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add r4, r4, r1, asl #5
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add r1, r4, r1, asl #6
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add r1, r1, #256 /* r1 = rv = (r1 + 256) >> 9 */
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mov r1, r1, asr #9
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rsb r2, r2, #128 /* r2 = guv = (-r2 + 128) >> 8 */
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mov r2, r2, asr #8
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add r0, r0, #2 /* r0 = bu = (Cb*128 + 256) >> 9 */
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mov r0, r0, asr #2
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stmia r8!, {r0-r2} /* store r0, r1 and r2 to chroma buffer */
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/* 1st loop, first pixel */
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ldrb r5, [r9], #1 /* r5 = *ysrc++ = *Y'_p++ */
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sub r5, r5, #16 /* r5 = (Y'-16) * 74 */
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add r3, r5, r5, asl #2
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add r5, r3, r5, asl #5
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add r6, r1, r5, asr #8 /* r6 = r = (Y >> 9) + rv */
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add r3, r2, r5, asr #7 /* r3 = g = (Y >> 8) + guv */
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add r4, r0, r5, asr #8 /* r4 = b = (Y >> 9) + bu */
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orr r5, r6, r4 /* check if clamping is needed... */
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orr r5, r5, r3, asr #1 /* ...at all */
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cmp r5, #31
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bls 15f /* -> no clamp */
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cmp r6, #31 /* clamp r */
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mvnhi r6, r6, asr #31
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andhi r6, r6, #31
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cmp r3, #63 /* clamp g */
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mvnhi r3, r3, asr #31
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andhi r3, r3, #63
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cmp r4, #31 /* clamp b */
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mvnhi r4, r4, asr #31
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andhi r4, r4, #31
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15: /* no clamp */
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/* calculate pixel_1 and save to r4 for later pixel packing */
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orr r4, r4, r3, lsl #5 /* pixel_1 = r<<11 | g<<5 | b */
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orr r4, r4, r6, lsl #11 /* r4 = pixel_1 */
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/* 1st loop, second pixel */
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ldrb r5, [r9], #1 /* r5 = *ysrc++ = *Y'_p++ */
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sub r5, r5, #16 /* r5 = (Y'-16) * 74 */
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add r3, r5, r5, asl #2
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add r5, r3, r5, asl #5
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add r6, r1, r5, asr #8 /* r6 = r = (Y >> 9) + rv */
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add r3, r2, r5, asr #7 /* r3 = g = (Y >> 8) + guv */
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add r5, r0, r5, asr #8 /* r5 = b = (Y >> 9) + bu */
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orr r0, r6, r5 /* check if clamping is needed... */
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orr r0, r0, r3, asr #1 /* ...at all */
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cmp r0, #31
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bls 15f /* -> no clamp */
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cmp r6, #31 /* clamp r */
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mvnhi r6, r6, asr #31
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andhi r6, r6, #31
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cmp r3, #63 /* clamp g */
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mvnhi r3, r3, asr #31
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andhi r3, r3, #63
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cmp r5, #31 /* clamp b */
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mvnhi r5, r5, asr #31
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andhi r5, r5, #31
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15: /* no clamp */
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/* calculate pixel_2 and pack with pixel_1 before writing */
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orr r5, r5, r3, lsl #5 /* pixel_2 = r<<11 | g<<5 | b */
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orr r5, r5, r6, lsl #11 /* r5 = pixel_2 */
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orr r4, r4, r5, lsl #16
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str r4, [lr], #4 /* write pixel_1 and pixel_2 */
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subs r7, r7, #2 /* check for loop end */
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bgt 10b /* back to beginning */
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/* 1st loop end */
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/* Reload several registers for pointer rewinding for next loop */
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add r8, sp, #12 /* chroma buffer */
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ldmia sp, {r7, r9} /* r7 = loop count */
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/* r9 = &ysrc[stride] */
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/* 2nd loop start */
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20: /* loop start */
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/* restore r0 (bu), r1 (rv) and r2 (guv) from chroma buffer */
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ldmia r8!, {r0-r2}
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/* 2nd loop, first pixel */
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ldrb r5, [r9], #1 /* r5 = *ysrc++ = *Y'_p++ */
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sub r5, r5, #16 /* r5 = (Y'-16) * 74 */
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add r3, r5, r5, asl #2
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add r5, r3, r5, asl #5
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add r6, r1, r5, asr #8 /* r6 = r = (Y >> 9) + rv */
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add r3, r2, r5, asr #7 /* r3 = g = (Y >> 8) + guv */
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add r4, r0, r5, asr #8 /* r4 = b = (Y >> 9) + bu */
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orr r5, r6, r4 /* check if clamping is needed... */
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orr r5, r5, r3, asr #1 /* ...at all */
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cmp r5, #31
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bls 15f /* -> no clamp */
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cmp r6, #31 /* clamp r */
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mvnhi r6, r6, asr #31
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andhi r6, r6, #31
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cmp r3, #63 /* clamp g */
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mvnhi r3, r3, asr #31
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andhi r3, r3, #63
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cmp r4, #31 /* clamp b */
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mvnhi r4, r4, asr #31
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andhi r4, r4, #31
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15: /* no clamp */
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/* calculate pixel_1 and save to r4 for later pixel packing */
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orr r4, r4, r3, lsl #5 /* pixel_1 = r<<11 | g<<5 | b */
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orr r4, r4, r6, lsl #11 /* r4 = pixel_1 */
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/* 2nd loop, second pixel */
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ldrb r5, [r9], #1 /* r5 = *ysrc++ = *Y'_p++ */
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sub r5, r5, #16 /* r5 = (Y'-16) * 74 */
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add r3, r5, r5, asl #2
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add r5, r3, r5, asl #5
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add r6, r1, r5, asr #8 /* r6 = r = (Y >> 9) + rv */
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add r3, r2, r5, asr #7 /* r3 = g = (Y >> 8) + guv */
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add r5, r0, r5, asr #8 /* r5 = b = (Y >> 9) + bu */
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orr r0, r6, r5 /* check if clamping is needed... */
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orr r0, r0, r3, asr #1 /* ...at all */
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cmp r0, #31
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bls 15f /* -> no clamp */
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cmp r6, #31 /* clamp r */
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mvnhi r6, r6, asr #31
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andhi r6, r6, #31
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cmp r3, #63 /* clamp g */
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mvnhi r3, r3, asr #31
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andhi r3, r3, #63
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cmp r5, #31 /* clamp b */
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mvnhi r5, r5, asr #31
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andhi r5, r5, #31
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15: /* no clamp */
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/* calculate pixel_2 and pack with pixel_1 before writing */
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orr r5, r5, r3, lsl #5 /* pixel_2 = r<<11 | g<<5 | b */
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orr r5, r5, r6, lsl #11 /* r5 = pixel_2 */
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orr r4, r4, r5, lsl #16
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str r4, [lr], #4 /* write pixel_1 and pixel_2 */
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subs r7, r7, #2 /* check for loop end */
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bgt 20b /* back to beginning */
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/* 2nd loop end */
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ldr r3, [sp, #8]
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add sp, sp, r3 /* deallocate buffer */
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ldmpc regs=r4-r10 /* restore registers */
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.ltorg
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.size lcd_write_yuv420_lines, .-lcd_write_yuv420_lines
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#elif (YUV2RGB_VERSION == VERSION_ARMV4)
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/****************************************************************************
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* extern void lcd_write_yuv420_lines(unsigned char const * const src[3],
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* uint16_t* out,
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* int width,
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* int stride);
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*
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* Conversion from Motion JPEG and MPEG Y'PbPr to RGB is:
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* |R| |1.164 0.000 1.596| |Y' - 16|
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* |G| = |1.164 -0.391 -0.813| |Pb - 128|
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* |B| |1.164 2.018 0.000| |Pr - 128|
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*
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* Scaled, normalized, rounded and tweaked to yield RGB 565:
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* |R| |74 0 101| |Y' - 16| >> 9
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* |G| = |74 -24 -51| |Cb - 128| >> 8
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* |B| |74 128 0| |Cr - 128| >> 9
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*
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* Converts two lines from YUV420 to RGB565, within each iteration four
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* pixels (2 per line) are calculated and written to destination buffer.
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*/
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.section .icode, "ax", %progbits
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.align 2
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.global lcd_write_yuv420_lines
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.type lcd_write_yuv420_lines, %function
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lcd_write_yuv420_lines:
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/* r0 = src = yuv_src */
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/* r1 = dst = out */
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/* r2 = width */
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/* r3 = stride */
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stmfd sp!, {r4-r11,lr} /* save non-scratch */
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ldmia r0, {r10-r12} /* r10 = yuv_src[0] = Y'_p */
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/* r11 = yuv_src[1] = Cb_p */
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/* r12 = yuv_src[2] = Cr_p */
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mov r9, r2, lsl #1 /* r9 = 2*width (loop count) */
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str r9, [sp, #-4]! /* [--sp] = 2*width (constant) */
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add r8, r10, r3 /* r8 = Y'_p + stride = Y'stride_p */
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mov lr, r1 /* RGB565 data destination buffer */
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10: /* loop start */
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ldrb r0, [r11], #1 /* r0 = *Cb_p++ */
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ldrb r1, [r12], #1 /* r1 = *Cr_p++ */
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ldrb r3, [r8], #1 /* r3 = Y'3 */
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ldrb r4, [r8], #1 /* r4 = Y'4 */
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sub r0, r0, #128 /* r0 = Cb-128 */
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sub r1, r1, #128 /* r1 = Cr-128 */
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add r2, r1, r1, asl #1 /* r2 = Cr*51 + Cb*24 */
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add r2, r2, r2, asl #4
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add r2, r2, r0, asl #3
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add r2, r2, r0, asl #4
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add r5, r1, r1, asl #2 /* r1 = Cr*101 */
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add r5, r5, r1, asl #5
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add r1, r5, r1, asl #6
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add r1, r1, #256 /* r1 = rv = (r1 + 256) >> 9 */
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mov r1, r1, asr #9
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rsb r2, r2, #128 /* r2 = guv = (-r2 + 128) >> 8 */
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mov r2, r2, asr #8
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add r0, r0, #2 /* r0 = bu = (Cb*128 + 256) >> 9 */
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mov r0, r0, asr #2
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/* pixel_3 */
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sub r3, r3, #16 /* r3 = (Y'-16) * (74/2) */
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add r7, r3, r3, asl #2
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add r3, r7, r3, asl #5
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add r6, r1, r3, asr #8 /* r6 = r = (Y >> 9) + rv */
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add r7, r2, r3, asr #7 /* r7 = g = (Y >> 8) + guv */
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add r5, r0, r3, asr #8 /* r5 = b = (Y >> 9) + bu */
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orr r3, r6, r5 /* check if clamping is needed... */
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orr r3, r3, r7, asr #1 /* ...at all */
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cmp r3, #31
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bls 15f /* no clamp */
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cmp r6, #31 /* clamp r */
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mvnhi r6, r6, asr #31
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andhi r6, r6, #31
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cmp r7, #63 /* clamp g */
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mvnhi r7, r7, asr #31
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andhi r7, r7, #63
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cmp r5, #31 /* clamp b */
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mvnhi r5, r5, asr #31
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andhi r5, r5, #31
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15: /* no clamp */
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/* calculate pixel_3 and save to r5 for later pixel packing */
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orr r5, r5, r7, lsl #5 /* pixel_3 = r<<11 | g<<5 | b */
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orr r5, r5, r6, lsl #11 /* r5 = pixel_3 */
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/* pixel_4 */
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sub r4, r4, #16 /* r4 = (Y'-16) * (74/2) */
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add r7, r4, r4, asl #2
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add r4, r7, r4, asl #5
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add r6, r1, r4, asr #8 /* r6 = r = (Y >> 9) + rv */
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add r7, r2, r4, asr #7 /* r7 = g = (Y >> 8) + guv */
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add r4, r0, r4, asr #8 /* r4 = b = (Y >> 9) + bu */
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orr r3, r6, r4 /* check if clamping is needed... */
|
|
orr r3, r3, r7, asr #1 /* ...at all */
|
|
cmp r3, #31
|
|
bls 15f /* no clamp */
|
|
cmp r6, #31 /* clamp r */
|
|
mvnhi r6, r6, asr #31
|
|
andhi r6, r6, #31
|
|
cmp r7, #63 /* clamp g */
|
|
mvnhi r7, r7, asr #31
|
|
andhi r7, r7, #63
|
|
cmp r4, #31 /* clamp b */
|
|
mvnhi r4, r4, asr #31
|
|
andhi r4, r4, #31
|
|
15: /* no clamp */
|
|
|
|
/* calculate pixel_4 and pack with pixel_3 before writing */
|
|
orr r4, r4, r7, lsl #5 /* pixel_4 = r<<11 | g<<5 | b */
|
|
orr r4, r4, r6, lsl #11 /* r4 = pixel_4 */
|
|
orr r5, r5, r4, lsl #16 /* r5 = pixel_4<<16 | pixel_3 */
|
|
|
|
ldr r7, [sp] /* r7 = 2*width */
|
|
ldrb r3, [r10], #1 /* r3 = Y'1 */
|
|
ldrb r4, [r10], #1 /* r4 = Y'2 */
|
|
|
|
str r5, [lr, r7] /* write pixel_3 and pixel_4 */
|
|
|
|
/* pixel_1 */
|
|
sub r3, r3, #16 /* r3 = (Y'-16) * (74/2) */
|
|
add r7, r3, r3, asl #2
|
|
add r3, r7, r3, asl #5
|
|
|
|
add r6, r1, r3, asr #8 /* r6 = r = (Y >> 9) + rv */
|
|
add r7, r2, r3, asr #7 /* r7 = g = (Y >> 8) + guv */
|
|
add r5, r0, r3, asr #8 /* r5 = b = (Y >> 9) + bu */
|
|
|
|
orr r3, r6, r5 /* check if clamping is needed... */
|
|
orr r3, r3, r7, asr #1 /* ...at all */
|
|
cmp r3, #31
|
|
bls 15f /* no clamp */
|
|
cmp r6, #31 /* clamp r */
|
|
mvnhi r6, r6, asr #31
|
|
andhi r6, r6, #31
|
|
cmp r7, #63 /* clamp g */
|
|
mvnhi r7, r7, asr #31
|
|
andhi r7, r7, #63
|
|
cmp r5, #31 /* clamp b */
|
|
mvnhi r5, r5, asr #31
|
|
andhi r5, r5, #31
|
|
15: /* no clamp */
|
|
|
|
/* calculate pixel_1 and save to r5 for later pixel packing */
|
|
orr r5, r5, r7, lsl #5 /* pixel_1 = r<<11 | g<<5 | b */
|
|
orr r5, r5, r6, lsl #11 /* r5 = pixel_1 */
|
|
|
|
/* pixel_2 */
|
|
sub r4, r4, #16 /* r4 = (Y'-16) * (74/2) */
|
|
add r7, r4, r4, asl #2
|
|
add r4, r7, r4, asl #5
|
|
|
|
add r6, r1, r4, asr #8 /* r6 = r = (Y >> 9) + rv */
|
|
add r7, r2, r4, asr #7 /* r7 = g = (Y >> 8) + guv */
|
|
add r4, r0, r4, asr #8 /* r4 = b = (Y >> 9) + bu */
|
|
|
|
orr r3, r6, r4 /* check if clamping is needed... */
|
|
orr r3, r3, r7, asr #1 /* ...at all */
|
|
cmp r3, #31
|
|
bls 15f /* no clamp */
|
|
cmp r6, #31 /* clamp r */
|
|
mvnhi r6, r6, asr #31
|
|
andhi r6, r6, #31
|
|
cmp r7, #63 /* clamp g */
|
|
mvnhi r7, r7, asr #31
|
|
andhi r7, r7, #63
|
|
cmp r4, #31 /* clamp b */
|
|
mvnhi r4, r4, asr #31
|
|
andhi r4, r4, #31
|
|
15: /* no clamp */
|
|
|
|
/* calculate pixel_2 and pack with pixel_1 before writing */
|
|
orr r4, r4, r7, lsl #5 /* pixel_2 = r<<11 | g<<5 | b */
|
|
orr r4, r4, r6, lsl #11 /* r4 = pixel_2 */
|
|
orr r5, r5, r4, lsl #16 /* r5 = pixel_2<<16 | pixel_1 */
|
|
|
|
str r5, [lr], #4 /* write pixel_1 and pixel_2 */
|
|
|
|
subs r9, r9, #4 /* check for loop end */
|
|
bgt 10b /* back to beginning */
|
|
|
|
/* loop end */
|
|
add sp, sp, #4 /* deallocate stack */
|
|
ldmpc regs=r4-r11 /* restore registers */
|
|
|
|
.ltorg
|
|
.size lcd_write_yuv420_lines, .-lcd_write_yuv420_lines
|
|
|
|
|
|
#elif (YUV2RGB_VERSION == VERSION_ARMV5TE)
|
|
/****************************************************************************
|
|
* How do I encode Y'CBCR components from R'G'B' in [0, +1]? (see ColorFAQ)
|
|
* |R| |0.00456621 0 0.00625893| |Y' - 16|
|
|
* |G| = |0.00456621 -0.00153632 -0.00318811| |Pb - 128|
|
|
* |B| |0.00456621 0.00791071 0 | |Pr - 128|
|
|
*
|
|
* Scaled, normalized, rounded and tweaked to yield RGB 565:
|
|
* |R| |74 0 101| |Y' - 16| >> 9
|
|
* |G| = |74 -24 -51| |Cb - 128| >> 8
|
|
* |B| |74 128 0| |Cr - 128| >> 9
|
|
*/
|
|
#define NBR 14 /* 14-bit resolution (SVN) */
|
|
#define COEF_C0 74
|
|
#define COEF_C1 101
|
|
#define COEF_C2 -24
|
|
#define COEF_C3 -51
|
|
#define COEF_C4 128
|
|
#define C4_IS_POW2
|
|
|
|
/* constant for rounding a NBR number before down-scaling it to RS bits */
|
|
#define ROUND(RS) (1 << (NBR - RS - 1))
|
|
|
|
/* packed 16-bit coefficients */
|
|
#define COEF_C4_C1 ((COEF_C4 << 16) | (COEF_C1 & 0xffff))
|
|
#define COEF_2C3_2C2 ((COEF_C3 << 17) | ((COEF_C2 << 1) & 0xffff))
|
|
/* 32-bit MLA constants */
|
|
#define CONST_MLA_Y (-16 * COEF_C0)
|
|
|
|
/****************************************************************************
|
|
* extern void lcd_write_yuv420_lines(unsigned char const * const src[3],
|
|
* uint16_t* out,
|
|
* int width,
|
|
* int stride);
|
|
*
|
|
* Converts two lines from YUV420 to RGB565, within each iteration four
|
|
* pixels (2 per line) are calculated and written to destination buffer.
|
|
*
|
|
* - use ARMv5TE+ 1-cycle multiply+accumulator instructions.
|
|
*/
|
|
.section .icode, "ax", %progbits
|
|
|
|
.align 2
|
|
.global lcd_write_yuv420_lines
|
|
.type lcd_write_yuv420_lines, %function
|
|
|
|
lcd_write_yuv420_lines:
|
|
@ r0 = src = yuv_src
|
|
@ r1 = out = dst_p
|
|
@ r2 = width
|
|
@ r3 = stride
|
|
stmfd sp!, {r4-r11,lr} @ save non-scratch
|
|
ldmia r0, {r10-r12} @ r10 = yuv_src[0] = Y'_p
|
|
@ r11 = yuv_src[1] = Cb_p
|
|
@ r12 = yuv_src[2] = Cr_p
|
|
adr r0, const_data @ load constants
|
|
ldmia r0, {r5-r8} @ r5 = COEF_C4_C1
|
|
@ r6 = COEF_2C3_2C2
|
|
@ r7 = COEF_C0
|
|
@ r8 = CONST_MLA_Y
|
|
sub r4, r12, r11 @ r4 = Cr_p-Cb_p
|
|
mov r9, r2, asl #1 @ r9 = 2*width
|
|
stmfd sp!, {r4-r6,r9} @ SP -> Cr_p-Cb_p
|
|
@ COEF_C4_C1
|
|
@ COEF_2C3_2C2
|
|
@ 2*width
|
|
add r12, r10, r3 @ r12 = Y'_p + stride = Y'stride_p
|
|
mov lr, r1 @ RGB565 data destination buffer
|
|
orr r9, r7, r2, lsl #15 @ loop_count = width/2;
|
|
@ r9 = loop_count<<16 | COEF_C0
|
|
sub r9, r9, #0x10000 @ loop_count--
|
|
|
|
10: @ loop_start
|
|
|
|
@ register usage:
|
|
@ r8 = CONST_MLA_Y
|
|
@ r9 = loop count<<16 | COEF_C0
|
|
@ r10 = Y'_p
|
|
@ r11 = Cb_p
|
|
@ r12 = Y'stride_p
|
|
@ lr = dst_p
|
|
@ free: r0-r7
|
|
|
|
ldmia sp, {r2-r4} @ r2 = Cr_p-Cb_p
|
|
@ r3 = COEF_C4_C1
|
|
@ r4 = COEF_2C3_2C2
|
|
mov r5, #ROUND(5) @ r5 = round constant
|
|
|
|
ldrb r6, [r12], #1 @ r6 = Y'3
|
|
ldrb r7, [r12], #1 @ r7 = Y'4
|
|
|
|
ldrb r1, [r11, r2] @ r1 = Cr = *Cr_p++
|
|
ldrb r0, [r11], #1 @ r0 = Cb = *Cb_p++
|
|
|
|
/* calculate Y3 and Y4 */
|
|
smlabb r6, r6, r9, r8 @ r6 = Y3 = C0*Y'3 - C0*16
|
|
smlabb r7, r7, r9, r8 @ r7 = Y4 = C0*Y'4 - C0*16
|
|
|
|
/* calculate rv, guv, bu */
|
|
sub r1, r1, #128 @ r1 = Cr" = Cr-128
|
|
sub r0, r0, #128 @ r0 = Cb" = Cb-128
|
|
|
|
smlabt r2, r1, r4, r5 @ r2 = guv" = Cr"*(2*C2) +
|
|
smlabb r2, r0, r4, r2 @ Cb"*(2*C3) + round
|
|
smlabb r1, r1, r3, r5 @ r1 = rv" = Cr"*C1 + round
|
|
#ifdef C4_IS_POW2
|
|
add r0, r5, r0, asl #NBR-7 @ r0 = bu" = Cb"*C4 + round
|
|
#else
|
|
smlabt r0, r0, r3, r5 @ r0 = bu" = Cb"*C4 + round
|
|
#endif
|
|
|
|
/* scale rv",guv",bu" */
|
|
mov r2, r2, asr #NBR-5 @ r2 = guv = guv" >> scale
|
|
mov r1, r1, asr #NBR-5 @ r1 = rv = rv" >> scale
|
|
mov r0, r0, asr #NBR-5 @ r0 = bu = bu" >> scale
|
|
|
|
@ register usage:
|
|
@ r8-r12,lr: pointers, counters
|
|
@ r0,r1,r2 = bu,rv,guv (rounded and scaled to RGB565)
|
|
@ r6,r7 = Y'3,Y'4
|
|
@ free: r3-r5
|
|
|
|
/* pixel_3 */
|
|
add r5, r1, r6, asr #NBR-5 @ r5 = r = (Y3 >> scale) + rv
|
|
add r4, r2, r6, asr #NBR-6 @ r4 = g = (Y3 >> scale) + guv
|
|
add r3, r0, r6, asr #NBR-5 @ r3 = b = (Y3 >> scale) + bu
|
|
|
|
orr r6, r5, r3 @ check if clamping is needed...
|
|
orr r6, r6, r4, asr #1 @ ...at all
|
|
cmp r6, #31
|
|
bls 15f @ no clamp
|
|
cmp r5, #31 @ clamp r
|
|
mvnhi r5, r5, asr #31
|
|
andhi r5, r5, #31
|
|
cmp r4, #63 @ clamp g
|
|
mvnhi r4, r4, asr #31
|
|
andhi r4, r4, #63
|
|
cmp r3, #31 @ clamp b
|
|
mvnhi r3, r3, asr #31
|
|
andhi r3, r3, #31
|
|
15: @ no clamp
|
|
|
|
/* calculate pixel_3 and save to r3 for later pixel packing */
|
|
orr r3, r3, r4, lsl #5 @ r3 = pixel_3 = r<<11 | g<<5 | b
|
|
orr r3, r3, r5, lsl #11
|
|
|
|
/* pixel_4 */
|
|
add r5, r1, r7, asr #NBR-5 @ r5 = r = (Y4 >> scale) + rv
|
|
add r4, r2, r7, asr #NBR-6 @ r4 = g = (Y4 >> scale) + guv
|
|
add r7, r0, r7, asr #NBR-5 @ r7 = b = (Y4 >> scale) + bu
|
|
|
|
orr r6, r5, r7 @ check if clamping is needed...
|
|
orr r6, r6, r4, asr #1 @ ...at all
|
|
cmp r6, #31
|
|
bls 15f @ no clamp
|
|
cmp r5, #31 @ clamp r
|
|
mvnhi r5, r5, asr #31
|
|
andhi r5, r5, #31
|
|
cmp r4, #63 @ clamp g
|
|
mvnhi r4, r4, asr #31
|
|
andhi r4, r4, #63
|
|
cmp r7, #31 @ clamp b
|
|
mvnhi r7, r7, asr #31
|
|
andhi r7, r7, #31
|
|
15: @ no clamp
|
|
|
|
/* calculate pixel_4 and pack with pixel_3 before writing */
|
|
orr r7, r7, r4, lsl #5 @ r7 = pixel_4 = r<<11 | g<<5 | b
|
|
orr r7, r7, r5, lsl #11
|
|
orr r3, r3, r7, lsl #16 @ r3 = pixel_4<<16 | pixel_3
|
|
|
|
/* avoid interlocks when writing pixel_3 and pixel_4 */
|
|
ldr r5, [sp, #12] @ r5 = 2*width
|
|
|
|
ldrb r6, [r10], #1 @ r6 = Y'1
|
|
ldrb r7, [r10], #1 @ r7 = Y'2
|
|
|
|
/* write pixel_3 and pixel_4 */
|
|
str r3, [lr, r5] @ [dst_p + 2*width] = r3
|
|
|
|
@ register usage:
|
|
@ r8-r12,lr: pointers, counters
|
|
@ r0,r1,r2 = bu,rv,guv (rounded and scaled to RGB565)
|
|
@ r6,r7 = Y'1,Y'2
|
|
@ free: r3-r5
|
|
|
|
/* calculate Y1 and Y2 */
|
|
smlabb r6, r6, r9, r8 @ r6 = Y1 = C0*Y'1 - C0*16
|
|
smlabb r7, r7, r9, r8 @ r7 = Y2 = C0*Y'2 - C0*16
|
|
|
|
/* pixel_1 */
|
|
add r5, r1, r6, asr #NBR-5 @ r5 = r = (Y1 >> scale) + rv
|
|
add r4, r2, r6, asr #NBR-6 @ r4 = g = (Y1 >> scale) + guv
|
|
add r3, r0, r6, asr #NBR-5 @ r3 = b = (Y1 >> scale) + bu
|
|
|
|
orr r6, r5, r3 @ check if clamping is needed...
|
|
orr r6, r6, r4, asr #1 @ ...at all
|
|
cmp r6, #31
|
|
bls 15f @ no clamp
|
|
cmp r5, #31 @ clamp r
|
|
mvnhi r5, r5, asr #31
|
|
andhi r5, r5, #31
|
|
cmp r4, #63 @ clamp g
|
|
mvnhi r4, r4, asr #31
|
|
andhi r4, r4, #63
|
|
cmp r3, #31 @ clamp b
|
|
mvnhi r3, r3, asr #31
|
|
andhi r3, r3, #31
|
|
15: @ no clamp
|
|
|
|
/* calculate pixel_1 and save to r3 for later pixel packing */
|
|
orr r3, r3, r4, lsl #5 @ r3 = pixel_1 = r<<11 | g<<5 | b
|
|
orr r3, r3, r5, lsl #11
|
|
|
|
/* pixel_2 */
|
|
add r5, r1, r7, asr #NBR-5 @ r5 = r = (Y2 >> scale) + rv
|
|
add r4, r2, r7, asr #NBR-6 @ r4 = g = (Y2 >> scale) + guv
|
|
add r7, r0, r7, asr #NBR-5 @ r7 = b = (Y2 >> scale) + bu
|
|
|
|
orr r6, r5, r7 @ check if clamping is needed...
|
|
orr r6, r6, r4, asr #1 @ ...at all
|
|
cmp r6, #31
|
|
bls 15f @ no clamp
|
|
cmp r5, #31 @ clamp r
|
|
mvnhi r5, r5, asr #31
|
|
andhi r5, r5, #31
|
|
cmp r4, #63 @ clamp g
|
|
mvnhi r4, r4, asr #31
|
|
andhi r4, r4, #63
|
|
cmp r7, #31 @ clamp b
|
|
mvnhi r7, r7, asr #31
|
|
andhi r7, r7, #31
|
|
15: @ no clamp
|
|
|
|
/* calculate pixel_2 and pack with pixel_1 before writing */
|
|
orr r7, r7, r4, lsl #5 @ r7 = pixel_2 = r<<11 | g<<5 | b
|
|
orr r7, r7, r5, lsl #11
|
|
orr r3, r3, r7, lsl #16 @ r3 = pixel_2 << 16 | pixel_1
|
|
|
|
str r3, [lr], #4 @ write pixel_1 and pixel_2
|
|
|
|
/* check for loop end */
|
|
subs r9, r9, #0x10000 @ loop_count--
|
|
bge 10b @ back to beginning
|
|
|
|
/* bye */
|
|
add sp, sp, #16
|
|
ldmpc regs=r4-r11 @ restore registers
|
|
|
|
.ltorg
|
|
.size lcd_write_yuv420_lines, .-lcd_write_yuv420_lines
|
|
|
|
/* data */
|
|
.align 2
|
|
const_data:
|
|
.word COEF_C4_C1
|
|
.word COEF_2C3_2C2
|
|
.word COEF_C0
|
|
.word CONST_MLA_Y
|
|
|
|
.size const_data, .-const_data
|
|
|
|
|
|
#else /* YUV2RGB_VERSION == VERSION_ARMV5TE_WST */
|
|
/****************************************************************************
|
|
* How do I encode Y'CBCR components from R'G'B' in [0, +1]? (see ColorFAQ)
|
|
* |R| |0.00456621 0 0.00625893| |Y' - 16|
|
|
* |G| = |0.00456621 -0.00153632 -0.00318811| |Pb - 128|
|
|
* |B| |0.00456621 0.00791071 0 | |Pr - 128|
|
|
*
|
|
* Scaled, normalized, rounded and tweaked to yield RGB 565:
|
|
* |R| |74 0 101| |Y' - 16| >> 9
|
|
* |G| = |74 -24 -51| |Cb - 128| >> 8
|
|
* |B| |74 128 0| |Cr - 128| >> 9
|
|
*/
|
|
#define NBR 14 /* 14-bit resolution (SVN) */
|
|
#define COEF_C0 74
|
|
#define COEF_C1 101
|
|
#define COEF_C2 -24
|
|
#define COEF_C3 -51
|
|
#define COEF_C4 128
|
|
#define C4_IS_POW2
|
|
|
|
/* packed 16-bit coefficients */
|
|
#define COEF_C4_C1 ((COEF_C4 << 16) | (COEF_C1 & 0xffff))
|
|
#define COEF_C3_C2 ((COEF_C3 << 16) | (COEF_C2 & 0xffff))
|
|
|
|
/* constant for rounding an NBR number before down-scaling it to RS bits */
|
|
#define ROUND(RS) (1 << (NBR - RS - 1))
|
|
|
|
/* 32-bit MLA constants */
|
|
#define CONST_MLA_Y (-16 * COEF_C0)
|
|
#define CONST_MLA_RV ((-128 * COEF_C1) + ROUND(5))
|
|
#define CONST_MLA_BU ((-128 * COEF_C4) + ROUND(5))
|
|
/* trick to save the register needed for table_sat6 reference:
|
|
add table_sat6-table_sat5 offset (conveniently scaled) to guv MLA */
|
|
#define CONST_MLA_GUV (-128 * (COEF_C2 + COEF_C3) + ROUND(6) + \
|
|
((table_sat6 - table_sat5) << (NBR - 6)))
|
|
|
|
/****************************************************************************
|
|
* extern void lcd_write_yuv420_lines(unsigned char const * const src[3],
|
|
* uint16_t* out,
|
|
* int width,
|
|
* int stride);
|
|
*
|
|
* Converts two lines from YUV420 to RGB565, within each iteration four
|
|
* pixels (2 per line) are calculated and written to destination buffer.
|
|
*
|
|
* - use ARMv5TE+ 1-cycle multiply+accumulator instructions.
|
|
* - use data tables (256 bytes) for RBG565 saturation.
|
|
*/
|
|
.section .icode, "ax", %progbits
|
|
|
|
.align 2
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.global lcd_write_yuv420_lines
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.type lcd_write_yuv420_lines, %function
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lcd_write_yuv420_lines:
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@ r0 = src = yuv_src
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@ r1 = out = dst1_p
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@ r2 = width
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@ r3 = stride
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stmfd sp!, {r4-r11,lr} @ save non-scratch
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ldmia r0, {r10-r12} @ r10 = yuv_src[0] = Y'_p
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@ r11 = yuv_src[1] = Cb_p
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@ r12 = yuv_src[2] = Cr_p
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/* prepare data and fill stack */
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adr r0, const_data @ load constants
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ldmia r0, {r4-r9,lr} @ r4 = COEF_C0
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@ r5 = CONST_MLA_GUV
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@ r6 = COEF_C3_C2
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@ r7 = CONST_MLA_BU
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@ r8 = COEF_C4_C1
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@ r9 = CONST_MLA_RV
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@ lr = table_sat5
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sub r0, r12, r11 @ r0 = Cr_p-Cb_p
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#define STACK_SZ 28
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stmfd sp!, {r0,r5-r9,lr} @ SP -> Cr_p-Cb_p
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@ CONST_MLA_GUV
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@ COEF_C3_C2
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@ CONST_MLA_BU
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@ COEF_C4_C1
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@ CONST_MLA_RV
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@ table_sat5
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mov r8, r4, lsl #4 @
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rsb r8, #0 @ r8 = -16*COEF_C0 = CONST_MLA_Y
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mov lr, r1 @ RGB565 data destination buffer
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add r9, lr, r2, asl #1 @ r9 = out + 2*width = dst2_p
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add r12, r3, r10 @ r12 = Y'_p + stride
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orr r7, r4, r2, lsl #15 @ loop_count = width/2;
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@ r7 = loop_count<<16 | COEF_C0
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sub r7, r7, #0x10000 @ loop_count--
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/* align loop code to minimize occupied lines, execution
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time per loop is optimized ~10% on ARM926EJ-S */
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.align CACHEALIGN_BITS
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loop_start:
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@ register usage:
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@ r7 = loop count<<16 | COEF_C0
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@ r8 = CONST_MLA_Y
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@ r9 = dst2_p
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@ r10 = Y'_p
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@ r11 = Cb_p
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@ r12 = Y'stride_p
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@ lr = dst1_p
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@ free: r0-r6
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/* load constants from stack */
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ldmia sp, {r1-r3,r6} @ r1 = Cr_p-Cb_p
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@ r2 = CONST_MLA_GUV
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@ r3 = COEF_C3_C2
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@ r6 = CONST_MLA_BU
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/* read Cr", Cb" */
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ldrb r1, [r11, r1] @ r1 = Cr = *Cr_p++
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ldrb r0, [r11], #1 @ r0 = Cb = *Cb_p++
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/* load more constants (avoids r1 interlock) */
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ldrd r4, [sp, #16] @ r4 = COEF_C4_C1
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@ r5 = CONST_MLA_RV
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/* calculate rv", guv", bu" */
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smlabt r2, r1, r3, r2 @ r2 = guv" = Cr*C2 + Cb*C3
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smlabb r2, r0, r3, r2 @ + CONST_MLA_GUV
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smlabb r1, r1, r4, r5 @ r1 = rv" = Cr*C1 + CONST_MLA_RV
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#ifdef C4_IS_POW2
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add r0, r6, r0, asl #NBR-7 @ r0 = bu" = Cb*C4 + CONST_MLA_BU
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#else
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smlabt r0, r0, r4, r6 @ r0 = bu" = Cb*C4 + CONST_MLA_BU
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#endif
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ldr r4, [sp, #STACK_SZ-4] @ r4 = table_sat5
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/* read Y'1 and Y'2 */
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ldrb r5, [r10], #1 @ r5 = Y'1 = *Y'_p++
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ldrb r6, [r10], #1 @ r6 = Y'2 = *Y'_p++
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/* scale rv",guv",bu", adding sat5_p here saves instructions later */
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add r1, r4, r1, asr #NBR-5 @ r1 = rv' = sat5_p + rv">>scale
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add r2, r4, r2, asr #NBR-6 @ r2 = guv' = sat5_p + guv">>scale
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add r0, r4, r0, asr #NBR-5 @ r0 = bu' = sat5_p + bu">>scale
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@ register usage:
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@ r7-r12,lr: pointers, counters, tables
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@ r0,r1,r2 = (bu,rv,guv) rounded and RGB565 scaled
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@ r5,r6 = Y'1,Y'2
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@ free: r3,r4
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/* calculate Y1 and Y2 */
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smlabb r5, r5, r7, r8 @ r5 = Y1 = C0*Y'1 - 16*C0
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smlabb r6, r6, r7, r8 @ r6 = Y2 = C0*Y'2 - 16*C0
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/* pixel_1 */
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ldrb r3, [r0, r5, asr #NBR-5] @ r3 = b = sat5[Y1>>scale + bu']
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ldrb r4, [r2, r5, asr #NBR-6] @ r4 = g = sat6[Y1>>scale + guv']
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ldrb r5, [r1, r5, asr #NBR-5] @ r5 = r = sat5[Y1>>scale + rv']
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/* calculate pixel_1 */
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orr r3, r3, r4, lsl #5 @ r3 = pixel_1 = g<<5 | b
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/* pixel_2 (avoid r5 interlock) */
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ldrb r4, [r0, r6, asr #NBR-5] @ r4 = b = sat5[Y2>>scale + bu']
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/* calculate pixel_1 and save to r3 for later pixel packing */
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orr r3, r3, r5, lsl #11 @ r3 = pixel_1 = r<<11 | g<<5 | b
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/* pixel_2 */
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ldrb r5, [r2, r6, asr #NBR-6] @ r5 = g = sat6[Y2>>scale + guv']
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ldrb r6, [r1, r6, asr #NBR-5] @ r6 = r = sat5[Y2>>scale + rv']
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/* calculate pixel_2 and pack with pixel_1 before writing */
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orr r3, r3, r4, lsl #16 @ r3 = pixel_2<<16 | pixel_1
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orr r3, r3, r5, lsl #21
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orr r3, r3, r6, lsl #27
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/* read Y'3 and Y'4 */
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ldrb r5, [r12], #1 @ r5 = Y'3 = *Y'stride_p++
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ldrb r6, [r12], #1 @ r6 = Y'4 = *Y'stride_p++
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/* write pixel_1 and pixel_2 */
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str r3, [lr], #4 @ *dst2_p++ = r3
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@ register usage:
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@ r7-r12,lr: pointers, counters, tables
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@ r0,r1,r2 = (bu,rv,guv) rounded and RGB565 scaled
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@ r5,r6 = Y'3,Y'4
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@ free: r3,r4
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/* calculate Y3 and Y4 */
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smlabb r5, r5, r7, r8 @ r5 = Y3 = C0*Y'3 - 16*C0
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smlabb r6, r6, r7, r8 @ r6 = Y4 = C0*Y'4 - 16*C0
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/* pixel_3 */
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ldrb r3, [r0, r5, asr #NBR-5] @ r3 = b = sat5[Y3>>scale + bu']
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ldrb r4, [r2, r5, asr #NBR-6] @ r4 = g = sat6[Y3>>scale + guv']
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ldrb r5, [r1, r5, asr #NBR-5] @ r5 = r = sat5[Y3>>scale + rv']
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/* calculate pixel_3 */
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orr r3, r3, r4, lsl #5 @ r3 = pixel_3 = g<<5 | b
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/* pixel_4 (avoid r5 interlock) */
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ldrb r4, [r0, r6, asr #NBR-5] @ r4 = b = sat5[Y4>>scale + bu']
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/* calculate pixel_3 and save to r3 for later pixel packing */
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orr r3, r3, r5, lsl #11 @ r3 = pixel_3 = r<<11 | g<<5 | b
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/* pixel_4 */
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ldrb r5, [r2, r6, asr #NBR-6] @ r5 = g = sat6[Y4>>scale + guv']
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ldrb r6, [r1, r6, asr #NBR-5] @ r6 = r = sat5[Y4>>scale + rv']
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/* calculate pixel_4 and pack with pixel_3 before writing */
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orr r3, r3, r4, lsl #16 @ r3 = pixel_4 << 16 | pixel_3
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orr r3, r3, r5, lsl #21
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orr r3, r3, r6, lsl #27
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/* write pixel_3 and pixel_4 */
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str r3, [r9], #4 @ *dst1_p++ = r3
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/* check for loop end */
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subs r7, r7, #0x10000 @ loop_count--
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bge loop_start @ back to beginning
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/* bye */
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add sp, sp, #STACK_SZ @ deallocate stack
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ldmpc regs=r4-r11 @ restore registers
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.ltorg
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.size lcd_write_yuv420_lines, .-lcd_write_yuv420_lines
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/* data */
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.align 2
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const_data:
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.word COEF_C0
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.word CONST_MLA_GUV
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.word COEF_C3_C2
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.word CONST_MLA_BU
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.word COEF_C4_C1
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.word CONST_MLA_RV
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.word table_sat5
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.size const_data, .-const_data
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/* saturation tables */
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/*.section .data*/
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/* aligned to cache line size to minimize cache usage */
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.align CACHEALIGN_BITS
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saturation_tables:
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/* 5-bit saturation table [-36..0..+67], size=104 */
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/* table_sat5[-36..-1] */
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.byte 0, 0, 0, 0
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.byte 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
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.byte 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
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table_sat5:
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/* table_sat5[0..67] */
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.byte 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15
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.byte 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31
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.byte 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31
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.byte 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31
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.byte 31, 31, 31, 31
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/* 6-bit saturation table [-44..0..+107], size=152 */
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/* table_sat6[-44..-1] */
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.byte 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
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.byte 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
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.byte 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
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table_sat6:
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/* table_sat6[0..107] */
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.byte 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15
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.byte 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31
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.byte 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47
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.byte 48, 49, 50, 51, 52, 53 ,54, 55, 56, 57, 58, 59, 60, 61, 62, 63
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.byte 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63
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.byte 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63
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.byte 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63, 63
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.size saturation_tables, .-saturation_tables
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#endif /* YUV2RGB_VERSION */
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