From b80266c45617acd5ef8ac5aa51a257222f611f4e Mon Sep 17 00:00:00 2001 From: Dave Chapman Date: Thu, 17 Aug 2006 08:37:35 +0000 Subject: Optimisations to lcd_yuv_blit by Tom Meyer - speeds up mpegplayer by about 10-15% git-svn-id: svn://svn.rockbox.org/rockbox/trunk@10627 a1c6a512-1295-4272-9138-f99709370657 --- docs/CREDITS | 1 + firmware/drivers/lcd-ipodvideo.c | 160 ++++++++++++++++++++++----------------- 2 files changed, 93 insertions(+), 68 deletions(-) diff --git a/docs/CREDITS b/docs/CREDITS index b62608d6c9..abde8a1b7f 100644 --- a/docs/CREDITS +++ b/docs/CREDITS @@ -225,3 +225,4 @@ Lars van de Klomp Philippe Miossec Jochen Kemnade Corry Lazarowitz +Tom Meyer diff --git a/firmware/drivers/lcd-ipodvideo.c b/firmware/drivers/lcd-ipodvideo.c index ef0ad4d2f3..237162b664 100644 --- a/firmware/drivers/lcd-ipodvideo.c +++ b/firmware/drivers/lcd-ipodvideo.c @@ -209,14 +209,15 @@ void lcd_update(void) #define CSUB_Y 2 #define RYFAC (31*257) -#define GYFAC (63*257) +#define GYFAC (31*257) #define BYFAC (31*257) #define RVFAC 11170 /* 31 * 257 * 1.402 */ -#define GVFAC (-11563) /* 63 * 257 * -0.714136 */ -#define GUFAC (-5572) /* 63 * 257 * -0.344136 */ +#define GVFAC (-5690) /* 31 * 257 * -0.714136 */ +#define GUFAC (-2742) /* 31 * 257 * -0.344136 */ #define BUFAC 14118 /* 31 * 257 * 1.772 */ #define ROUNDOFFS (127*257) +#define ROUNDOFFSG (63*257) /* Performance function to blit a YUV bitmap directly to the LCD */ void lcd_yuv_blit(unsigned char * const src[3], @@ -230,11 +231,12 @@ void lcd_yuv_blit(unsigned char * const src[3], if (finishup_needed) { unsigned int data; /* Bottom-half of original lcd_bcm_finishup() function */ - do { - /* This function takes about 14ms to execute - so we yield() */ + data = lcd_bcm_read32(0x1F8); + while (data == 0xFFFA0005 || data == 0xFFFF) { + /* This loop can wait for up to 14ms - so we yield() */ yield(); data = lcd_bcm_read32(0x1F8); - } while (data == 0xFFFA0005 || data == 0xFFFF); + } } lcd_bcm_read32(0x1FC); @@ -261,18 +263,23 @@ void lcd_yuv_blit(unsigned char * const src[3], ymax = y + height - 1 ; + const int stride_div_csub_x = stride/CSUB_X; + for (; y <= ymax ; y++) { /* upsampling, YUV->RGB conversion and reduction to RGB565 in one go */ const unsigned char *ysrc = src[0] + stride * src_y + src_x; - const unsigned char *usrc = src[1] + (stride/CSUB_X) * (src_y/CSUB_Y) - + (src_x/CSUB_X); - const unsigned char *vsrc = src[2] + (stride/CSUB_X) * (src_y/CSUB_Y) - + (src_x/CSUB_X); + + const int uvoffset = stride_div_csub_x * (src_y/CSUB_Y) + + (src_x/CSUB_X); + + const unsigned char *usrc = src[1] + uvoffset; + const unsigned char *vsrc = src[2] + uvoffset; const unsigned char *row_end = ysrc + width; int y, u, v; - int red, green, blue; + int red1, green1, blue1; + int red2, green2, blue2; unsigned rbits, gbits, bbits; int rc, gc, bc; @@ -282,73 +289,90 @@ void lcd_yuv_blit(unsigned char * const src[3], u = *usrc++ - 128; v = *vsrc++ - 128; rc = RVFAC * v + ROUNDOFFS; - gc = GVFAC * v + GUFAC * u + ROUNDOFFS; + gc = GVFAC * v + GUFAC * u + ROUNDOFFSG; bc = BUFAC * u + ROUNDOFFS; /* Pixel 1 */ y = *ysrc++; - red = RYFAC * y + rc; - green = GYFAC * y + gc; - blue = BYFAC * y + bc; - - if ((unsigned)red > (RYFAC*255+ROUNDOFFS)) - { - if (red < 0) - red = 0; - else - red = (RYFAC*255+ROUNDOFFS); - } - if ((unsigned)green > (GYFAC*255+ROUNDOFFS)) - { - if (green < 0) - green = 0; - else - green = (GYFAC*255+ROUNDOFFS); - } - if ((unsigned)blue > (BYFAC*255+ROUNDOFFS)) - { - if (blue < 0) - blue = 0; - else - blue = (BYFAC*255+ROUNDOFFS); - } - rbits = ((unsigned)red) >> 16 ; - gbits = ((unsigned)green) >> 16 ; - bbits = ((unsigned)blue) >> 16 ; - outw((rbits << 11) | (gbits << 5) | bbits, 0x30000000); + red1 = RYFAC * y + rc; + green1 = GYFAC * y + gc; + blue1 = BYFAC * y + bc; /* Pixel 2 */ y = *ysrc++; - red = RYFAC * y + rc; - green = GYFAC * y + gc; - blue = BYFAC * y + bc; - - if ((unsigned)red > (RYFAC*255+ROUNDOFFS)) - { - if (red < 0) - red = 0; - else - red = (RYFAC*255+ROUNDOFFS); - } - if ((unsigned)green > (GYFAC*255+ROUNDOFFS)) - { - if (green < 0) - green = 0; - else - green = (GYFAC*255+ROUNDOFFS); + red2 = RYFAC * y + rc; + green2 = GYFAC * y + gc; + blue2 = BYFAC * y + bc; + + /* Since out of bounds errors are relatively rare, we check two + pixels at once to see if any components are out of bounds, and + then fix whichever is broken. This works due to high values and + negative values both becoming larger than the cutoff when + casted to unsigned. And ORing them together checks all of them + simultaneously. */ + if (((unsigned)(red1 | green1 | blue1 | + red2 | green2 | blue2)) > (RYFAC*255+ROUNDOFFS)) { + if (((unsigned)(red1 | green1 | blue1)) > + (RYFAC*255+ROUNDOFFS)) { + if ((unsigned)red1 > (RYFAC*255+ROUNDOFFS)) + { + if (red1 < 0) + red1 = 0; + else + red1 = (RYFAC*255+ROUNDOFFS); + } + if ((unsigned)green1 > (GYFAC*255+ROUNDOFFSG)) + { + if (green1 < 0) + green1 = 0; + else + green1 = (GYFAC*255+ROUNDOFFSG); + } + if ((unsigned)blue1 > (BYFAC*255+ROUNDOFFS)) + { + if (blue1 < 0) + blue1 = 0; + else + blue1 = (BYFAC*255+ROUNDOFFS); + } + } + + if (((unsigned)(red2 | green2 | blue2)) > + (RYFAC*255+ROUNDOFFS)) { + if ((unsigned)red2 > (RYFAC*255+ROUNDOFFS)) + { + if (red2 < 0) + red2 = 0; + else + red2 = (RYFAC*255+ROUNDOFFS); + } + if ((unsigned)green2 > (GYFAC*255+ROUNDOFFSG)) + { + if (green2 < 0) + green2 = 0; + else + green2 = (GYFAC*255+ROUNDOFFSG); + } + if ((unsigned)blue2 > (BYFAC*255+ROUNDOFFS)) + { + if (blue2 < 0) + blue2 = 0; + else + blue2 = (BYFAC*255+ROUNDOFFS); + } + } } - if ((unsigned)blue > (BYFAC*255+ROUNDOFFS)) - { - if (blue < 0) - blue = 0; - else - blue = (BYFAC*255+ROUNDOFFS); - } - rbits = ((unsigned)red) >> 16 ; - gbits = ((unsigned)green) >> 16 ; - bbits = ((unsigned)blue) >> 16 ; + + rbits = red1 >> 16 ; + gbits = green1 >> 15 ; + bbits = blue1 >> 16 ; + + outw((rbits << 11) | (gbits << 5) | bbits, 0x30000000); + rbits = red2 >> 16 ; + gbits = green2 >> 15 ; + bbits = blue2 >> 16 ; outw((rbits << 11) | (gbits << 5) | bbits, 0x30000000); } while (ysrc < row_end); -- cgit v1.2.3