/*************************************************************************** * __________ __ ___. * Open \______ \ ____ ____ | | _\_ |__ _______ ___ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ * \/ \/ \/ \/ \/ * $Id$ * * JPEG image viewer * (This is a real mess if it has to be coded in one single C file) * * File scrolling addition (C) 2005 Alexander Spyridakis * Copyright (C) 2004 Jörg Hohensohn aka [IDC]Dragon * Heavily borrowed from the IJG implementation (C) Thomas G. Lane * Small & fast downscaling IDCT (C) 2002 by Guido Vollbeding JPEGclub.org * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY * KIND, either express or implied. * ****************************************************************************/ #include "plugin.h" #include "yuv2rgb.h" /* * Conversion of full 0-255 range YCrCb to RGB: * |R| |1.000000 -0.000001 1.402000| |Y'| * |G| = |1.000000 -0.334136 -0.714136| |Pb| * |B| |1.000000 1.772000 0.000000| |Pr| * Scaled (yields s15-bit output): * |R| |128 0 179| |Y | * |G| = |128 -43 -91| |Cb - 128| * |B| |128 227 0| |Cr - 128| */ #define YFAC 128 #define RVFAC 179 #define GUFAC (-43) #define GVFAC (-91) #define BUFAC 227 #define YUV_WHITE (255*YFAC) #define NODITHER_DELTA (127*YFAC) #define COMPONENT_SHIFT 15 #define MATRIX_SHIFT 7 static inline int clamp_component_bits(int x, int bits) { if ((unsigned)x > (1u << bits) - 1) x = x < 0 ? 0 : (1 << bits) - 1; return x; } static inline int component_to_lcd(int x, int bits, int delta) { /* Formula used in core bitmap loader. */ return (((1 << bits) - 1)*x + (x >> (8 - bits)) + delta) >> COMPONENT_SHIFT; } static inline int lcd_to_component(int x, int bits, int delta) { /* Reasonable, approximate reversal to get a full range back from the quantized value. */ return YUV_WHITE*x / ((1 << bits) - 1); (void)delta; } #define RED 0 #define GRN 1 #define BLU 2 struct rgb_err { int16_t errbuf[LCD_WIDTH+2]; /* Error record for line below */ } rgb_err_buffers[3]; struct rgb_pixel { int r, g, b; /* Current pixel components in s16.0 */ int inc; /* Current line increment (-1 or 1) */ int row; /* Current row in source image */ int col; /* Current column in source image */ int ce[3]; /* Errors to apply to current pixel */ struct rgb_err *e; /* RED, GRN, BLU */ int epos; /* Current position in error record */ }; struct rgb_pixel *pixel; /** round and truncate to lcd depth **/ static fb_data pixel_to_lcd_colour(void) { struct rgb_pixel *p = pixel; int r, g, b; r = component_to_lcd(p->r, LCD_RED_BITS, NODITHER_DELTA); r = clamp_component_bits(r, LCD_RED_BITS); g = component_to_lcd(p->g, LCD_GREEN_BITS, NODITHER_DELTA); g = clamp_component_bits(g, LCD_GREEN_BITS); b = component_to_lcd(p->b, LCD_BLUE_BITS, NODITHER_DELTA); b = clamp_component_bits(b, LCD_BLUE_BITS); return LCD_RGBPACK_LCD(r, g, b); } /** write a monochrome pixel to the colour LCD **/ static fb_data pixel_to_lcd_gray(void) { int r, g, b; g = clamp_component(pixel->g); r = component_to_lcd(g, LCD_RED_BITS, NODITHER_DELTA); b = component_to_lcd(g, LCD_BLUE_BITS, NODITHER_DELTA); g = component_to_lcd(g, LCD_GREEN_BITS, NODITHER_DELTA); return LCD_RGBPACK_LCD(r, g, b); } /** * Bayer ordered dithering - swiped from the core bitmap loader. */ static fb_data pixel_odither_to_lcd(void) { /* canonical ordered dither matrix */ static const unsigned char dither_matrix[16][16] = { { 0,192, 48,240, 12,204, 60,252, 3,195, 51,243, 15,207, 63,255 }, { 128, 64,176,112,140, 76,188,124,131, 67,179,115,143, 79,191,127 }, { 32,224, 16,208, 44,236, 28,220, 35,227, 19,211, 47,239, 31,223 }, { 160, 96,144, 80,172,108,156, 92,163, 99,147, 83,175,111,159, 95 }, { 8,200, 56,248, 4,196, 52,244, 11,203, 59,251, 7,199, 55,247 }, { 136, 72,184,120,132, 68,180,116,139, 75,187,123,135, 71,183,119 }, { 40,232, 24,216, 36,228, 20,212, 43,235, 27,219, 39,231, 23,215 }, { 168,104,152, 88,164,100,148, 84,171,107,155, 91,167,103,151, 87 }, { 2,194, 50,242, 14,206, 62,254, 1,193, 49,241, 13,205, 61,253 }, { 130, 66,178,114,142, 78,190,126,129, 65,177,113,141, 77,189,125 }, { 34,226, 18,210, 46,238, 30,222, 33,225, 17,209, 45,237, 29,221 }, { 162, 98,146, 82,174,110,158, 94,161, 97,145, 81,173,109,157, 93 }, { 10,202, 58,250, 6,198, 54,246, 9,201, 57,249, 5,197, 53,245 }, { 138, 74,186,122,134, 70,182,118,137, 73,185,121,133, 69,181,117 }, { 42,234, 26,218, 38,230, 22,214, 41,233, 25,217, 37,229, 21,213 }, { 170,106,154, 90,166,102,150, 86,169,105,153, 89,165,101,149, 85 } }; struct rgb_pixel *p = pixel; int r, g, b, delta; delta = dither_matrix[p->col & 15][p->row & 15] << MATRIX_SHIFT; r = component_to_lcd(p->r, LCD_RED_BITS, delta); r = clamp_component_bits(r, LCD_RED_BITS); g = component_to_lcd(p->g, LCD_GREEN_BITS, delta); g = clamp_component_bits(g, LCD_GREEN_BITS); b = component_to_lcd(p->b, LCD_BLUE_BITS, delta); b = clamp_component_bits(b, LCD_BLUE_BITS); p->col += p->inc; return LCD_RGBPACK_LCD(r, g, b); } /** * Floyd/Steinberg dither to lcd depth. * * Apply filter to each component in serpentine pattern. Kernel shown for * L->R scan. Kernel is reversed for R->L. * * 7 * 3 5 1 (1/16) */ static inline void distribute_error(int *ce, struct rgb_err *e, int err, int epos, int inc) { *ce = (7*err >> 4) + e->errbuf[epos+inc]; e->errbuf[epos+inc] = err >> 4; e->errbuf[epos] += 5*err >> 4; e->errbuf[epos-inc] += 3*err >> 4; } static fb_data pixel_fsdither_to_lcd(void) { struct rgb_pixel *p = pixel; int rc, gc, bc, r, g, b; int inc, epos; /* Full components with error terms */ rc = p->r + p->ce[RED]; r = component_to_lcd(rc, LCD_RED_BITS, 0); r = clamp_component_bits(r, LCD_RED_BITS); gc = p->g + p->ce[GRN]; g = component_to_lcd(gc, LCD_GREEN_BITS, 0); g = clamp_component_bits(g, LCD_GREEN_BITS); bc = p->b + p->ce[BLU]; b = component_to_lcd(bc, LCD_BLUE_BITS, 0); b = clamp_component_bits(b, LCD_BLUE_BITS); /* Get pixel errors */ rc -= lcd_to_component(r, LCD_RED_BITS, 0); gc -= lcd_to_component(g, LCD_GREEN_BITS, 0); bc -= lcd_to_component(b, LCD_BLUE_BITS, 0); /* Spead error to surrounding pixels. */ inc = p->inc; epos = p->epos; p->epos += inc; distribute_error(&p->ce[RED], &p->e[RED], rc, epos, inc); distribute_error(&p->ce[GRN], &p->e[GRN], gc, epos, inc); distribute_error(&p->ce[BLU], &p->e[BLU], bc, epos, inc); /* Pack and return pixel */ return LCD_RGBPACK_LCD(r, g, b); } /* Functions for each output mode, colour then grayscale. */ static fb_data (* const pixel_funcs[COLOUR_NUM_MODES][DITHER_NUM_MODES])(void) = { [COLOURMODE_COLOUR] = { [DITHER_NONE] = pixel_to_lcd_colour, [DITHER_ORDERED] = pixel_odither_to_lcd, [DITHER_DIFFUSION] = pixel_fsdither_to_lcd, }, [COLOURMODE_GRAY] = { [DITHER_NONE] = pixel_to_lcd_gray, [DITHER_ORDERED] = pixel_odither_to_lcd, [DITHER_DIFFUSION] = pixel_fsdither_to_lcd, }, }; /** * Draw a partial YUV colour bitmap * * Runs serpentine pattern when dithering is DITHER_DIFFUSION, else scan is * always L->R. */ void yuv_bitmap_part(unsigned char *src[3], int csub_x, int csub_y, int src_x, int src_y, int stride, int x, int y, int width, int height, int colour_mode, int dither_mode) { fb_data *dst, *dst_end; fb_data (*pixel_func)(void); struct rgb_pixel px; if (x + width > LCD_WIDTH) width = LCD_WIDTH - x; /* Clip right */ if (x < 0) width += x, x = 0; /* Clip left */ if (width <= 0) return; /* nothing left to do */ if (y + height > LCD_HEIGHT) height = LCD_HEIGHT - y; /* Clip bottom */ if (y < 0) height += y, y = 0; /* Clip top */ if (height <= 0) return; /* nothing left to do */ pixel = &px; dst = rb->lcd_framebuffer + LCD_WIDTH * y + x; dst_end = dst + LCD_WIDTH * height; if (colour_mode == COLOURMODE_GRAY) csub_y = 0; /* Ignore Cb, Cr */ pixel_func = pixel_funcs[colour_mode] [dither_mode]; if (dither_mode == DITHER_DIFFUSION) { /* Reset error terms. */ px.e = rgb_err_buffers; px.ce[RED] = px.ce[GRN] = px.ce[BLU] = 0; rb->memset(px.e, 0, 3*sizeof (struct rgb_err)); } do { fb_data *dst_row, *row_end; const unsigned char *ysrc; px.inc = 1; if (dither_mode == DITHER_DIFFUSION) { /* Use R->L scan on odd lines */ px.inc -= (src_y & 1) << 1; px.epos = x + 1; if (px.inc < 0) px.epos += width - 1; } if (px.inc == 1) { /* Scan is L->R */ dst_row = dst; row_end = dst_row + width; px.col = src_x; } else { /* Scan is R->L */ row_end = dst - 1; dst_row = row_end + width; px.col = src_x + width - 1; } ysrc = src[0] + stride * src_y + px.col; px.row = src_y; /* Do one row of pixels */ if (csub_y) /* colour */ { /* upsampling, YUV->RGB conversion and reduction to RGB565 in one go */ const unsigned char *usrc, *vsrc; usrc = src[1] + (stride/csub_x) * (src_y/csub_y) + (px.col/csub_x); vsrc = src[2] + (stride/csub_x) * (src_y/csub_y) + (px.col/csub_x); int xphase = px.col % csub_x; int xphase_reset = px.inc * csub_x; int y, v, u, rv, guv, bu; v = *vsrc - 128; vsrc += px.inc; u = *usrc - 128; usrc += px.inc; rv = RVFAC*v; guv = GUFAC*u + GVFAC*v; bu = BUFAC*u; while (1) { y = YFAC*(*ysrc); ysrc += px.inc; px.r = y + rv; px.g = y + guv; px.b = y + bu; *dst_row = pixel_func(); dst_row += px.inc; if (dst_row == row_end) break; xphase += px.inc; if ((unsigned)xphase < (unsigned)csub_x) continue; /* fetch new chromas */ v = *vsrc - 128; vsrc += px.inc; u = *usrc - 128; usrc += px.inc; rv = RVFAC*v; guv = GUFAC*u + GVFAC*v; bu = BUFAC*u; xphase -= xphase_reset; } } else /* monochrome */ { do { /* Set all components the same for dithering purposes */ px.g = px.r = px.b = YFAC*(*ysrc); *dst_row = pixel_func(); ysrc += px.inc; dst_row += px.inc; } while (dst_row != row_end); } src_y++; dst += LCD_WIDTH; } while (dst < dst_end); }