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Date: Tue, 4 Mar 2003 15:05:31 -0800 From: "Jim" Subject: [SDL] Frame Buffer patches... Okay I'm new at patch generation - so please tell me if there's a better way I could have done this. Attached are two patch files generated with 'cvs diff -u' SDL-fb-open-lock.patch applies to SDL_fbvideo.c Modifies the open loop to check /dev/fb/0 found on devfs... Modifies the lock code to return failure if the current virtual terminal is not the one opened for frame buffer writing... Lock would hang forever if switched away (ctrl-alt-F1) ... SDL-fb-mousedrv-screensave.patch applies to SDL_fbevents.c Switches default mouse mode based on SDL_MOUSEDRV - currently only accepts PS2 - otherwise default is MS Mouse. When the screen is switched - exisiting code (wrapped in ifdef SAVE_SCREEN_COTENTS) would save the wrong bit of the screen.... ( I run frame buffer 1600x1200, the size I requested was 800x600 - the save would save the top 800 lines (non biased) and restore them... Adding screen->offset fixed that ) However, if that option is not set, then a call to SDL_UpdateRect (full screen) is made. (which may have had it's contents changed since the screen is not entirely locked because of lock-failure patch) Jim [patches slightly tweaked for SDL 1.2.10]
author Sam Lantinga <slouken@libsdl.org>
date Wed, 22 Mar 2006 07:48:22 +0000
parents 5f52867ba65c
children 51038e80ae59
line wrap: on
line source

/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2006 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga
    slouken@libsdl.org
*/
#include "SDL_config.h"

/* This is the software implementation of the YUV video overlay support */

/* This code was derived from code carrying the following copyright notices:

 * Copyright (c) 1995 The Regents of the University of California.
 * All rights reserved.
 * 
 * Permission to use, copy, modify, and distribute this software and its
 * documentation for any purpose, without fee, and without written agreement is
 * hereby granted, provided that the above copyright notice and the following
 * two paragraphs appear in all copies of this software.
 * 
 * IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR
 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT
 * OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF
 * CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 * THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
 * ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATION TO
 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.

 * Copyright (c) 1995 Erik Corry
 * All rights reserved.
 * 
 * Permission to use, copy, modify, and distribute this software and its
 * documentation for any purpose, without fee, and without written agreement is
 * hereby granted, provided that the above copyright notice and the following
 * two paragraphs appear in all copies of this software.
 * 
 * IN NO EVENT SHALL ERIK CORRY BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT,
 * SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OF
 * THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF ERIK CORRY HAS BEEN ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 * ERIK CORRY SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 * PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS"
 * BASIS, AND ERIK CORRY HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT,
 * UPDATES, ENHANCEMENTS, OR MODIFICATIONS.

 * Portions of this software Copyright (c) 1995 Brown University.
 * All rights reserved.
 * 
 * Permission to use, copy, modify, and distribute this software and its
 * documentation for any purpose, without fee, and without written agreement
 * is hereby granted, provided that the above copyright notice and the
 * following two paragraphs appear in all copies of this software.
 * 
 * IN NO EVENT SHALL BROWN UNIVERSITY BE LIABLE TO ANY PARTY FOR
 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT
 * OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF BROWN
 * UNIVERSITY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 * BROWN UNIVERSITY SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 * PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS"
 * BASIS, AND BROWN UNIVERSITY HAS NO OBLIGATION TO PROVIDE MAINTENANCE,
 * SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
 */

#include "SDL_video.h"
#include "SDL_cpuinfo.h"
#include "SDL_stretch_c.h"
#include "SDL_yuvfuncs.h"
#include "SDL_yuv_sw_c.h"

/* The functions used to manipulate software video overlays */
static struct private_yuvhwfuncs sw_yuvfuncs = {
	SDL_LockYUV_SW,
	SDL_UnlockYUV_SW,
	SDL_DisplayYUV_SW,
	SDL_FreeYUV_SW
};

/* RGB conversion lookup tables */
struct private_yuvhwdata {
	SDL_Surface *stretch;
	SDL_Surface *display;
	Uint8 *pixels;
	int *colortab;
	Uint32 *rgb_2_pix;
	void (*Display1X)(int *colortab, Uint32 *rgb_2_pix,
                          unsigned char *lum, unsigned char *cr,
                          unsigned char *cb, unsigned char *out,
                          int rows, int cols, int mod );
	void (*Display2X)(int *colortab, Uint32 *rgb_2_pix,
	                  unsigned char *lum, unsigned char *cr,
                          unsigned char *cb, unsigned char *out,
                          int rows, int cols, int mod );

	/* These are just so we don't have to allocate them separately */
	Uint16 pitches[3];
	Uint8 *planes[3];
};


/* The colorspace conversion functions */

#if 0 /*defined(__GNUC__) && defined(__i386__) && SDL_ASSEMBLY_ROUTINES*/
extern void Color565DitherYV12MMX1X( int *colortab, Uint32 *rgb_2_pix,
                                     unsigned char *lum, unsigned char *cr,
                                     unsigned char *cb, unsigned char *out,
                                     int rows, int cols, int mod );
extern void ColorRGBDitherYV12MMX1X( int *colortab, Uint32 *rgb_2_pix,
                                     unsigned char *lum, unsigned char *cr,
                                     unsigned char *cb, unsigned char *out,
                                     int rows, int cols, int mod );
#endif 

static void Color16DitherYV12Mod1X( int *colortab, Uint32 *rgb_2_pix,
                                    unsigned char *lum, unsigned char *cr,
                                    unsigned char *cb, unsigned char *out,
                                    int rows, int cols, int mod )
{
    unsigned short* row1;
    unsigned short* row2;
    unsigned char* lum2;
    int x, y;
    int cr_r;
    int crb_g;
    int cb_b;
    int cols_2 = cols / 2;

    row1 = (unsigned short*) out;
    row2 = row1 + cols + mod;
    lum2 = lum + cols;

    mod += cols + mod;

    y = rows / 2;
    while( y-- )
    {
        x = cols_2;
        while( x-- )
        {
            register int L;

            cr_r   = 0*768+256 + colortab[ *cr + 0*256 ];
            crb_g  = 1*768+256 + colortab[ *cr + 1*256 ]
                               + colortab[ *cb + 2*256 ];
            cb_b   = 2*768+256 + colortab[ *cb + 3*256 ];
            ++cr; ++cb;

            L = *lum++;
            *row1++ = (unsigned short)(rgb_2_pix[ L + cr_r ] |
                                       rgb_2_pix[ L + crb_g ] |
                                       rgb_2_pix[ L + cb_b ]);

            L = *lum++;
            *row1++ = (unsigned short)(rgb_2_pix[ L + cr_r ] |
                                       rgb_2_pix[ L + crb_g ] |
                                       rgb_2_pix[ L + cb_b ]);


            /* Now, do second row.  */

            L = *lum2++;
            *row2++ = (unsigned short)(rgb_2_pix[ L + cr_r ] |
                                       rgb_2_pix[ L + crb_g ] |
                                       rgb_2_pix[ L + cb_b ]);

            L = *lum2++;
            *row2++ = (unsigned short)(rgb_2_pix[ L + cr_r ] |
                                       rgb_2_pix[ L + crb_g ] |
                                       rgb_2_pix[ L + cb_b ]);
        }

        /*
         * These values are at the start of the next line, (due
         * to the ++'s above),but they need to be at the start
         * of the line after that.
         */
        lum  += cols;
        lum2 += cols;
        row1 += mod;
        row2 += mod;
    }
}

static void Color24DitherYV12Mod1X( int *colortab, Uint32 *rgb_2_pix,
                                    unsigned char *lum, unsigned char *cr,
                                    unsigned char *cb, unsigned char *out,
                                    int rows, int cols, int mod )
{
    unsigned int value;
    unsigned char* row1;
    unsigned char* row2;
    unsigned char* lum2;
    int x, y;
    int cr_r;
    int crb_g;
    int cb_b;
    int cols_2 = cols / 2;

    row1 = out;
    row2 = row1 + cols*3 + mod*3;
    lum2 = lum + cols;

    mod += cols + mod;
    mod *= 3;

    y = rows / 2;
    while( y-- )
    {
        x = cols_2;
        while( x-- )
        {
            register int L;

            cr_r   = 0*768+256 + colortab[ *cr + 0*256 ];
            crb_g  = 1*768+256 + colortab[ *cr + 1*256 ]
                               + colortab[ *cb + 2*256 ];
            cb_b   = 2*768+256 + colortab[ *cb + 3*256 ];
            ++cr; ++cb;

            L = *lum++;
            value = (rgb_2_pix[ L + cr_r ] |
                     rgb_2_pix[ L + crb_g ] |
                     rgb_2_pix[ L + cb_b ]);
            *row1++ = (value      ) & 0xFF;
            *row1++ = (value >>  8) & 0xFF;
            *row1++ = (value >> 16) & 0xFF;

            L = *lum++;
            value = (rgb_2_pix[ L + cr_r ] |
                     rgb_2_pix[ L + crb_g ] |
                     rgb_2_pix[ L + cb_b ]);
            *row1++ = (value      ) & 0xFF;
            *row1++ = (value >>  8) & 0xFF;
            *row1++ = (value >> 16) & 0xFF;


            /* Now, do second row.  */

            L = *lum2++;
            value = (rgb_2_pix[ L + cr_r ] |
                     rgb_2_pix[ L + crb_g ] |
                     rgb_2_pix[ L + cb_b ]);
            *row2++ = (value      ) & 0xFF;
            *row2++ = (value >>  8) & 0xFF;
            *row2++ = (value >> 16) & 0xFF;

            L = *lum2++;
            value = (rgb_2_pix[ L + cr_r ] |
                     rgb_2_pix[ L + crb_g ] |
                     rgb_2_pix[ L + cb_b ]);
            *row2++ = (value      ) & 0xFF;
            *row2++ = (value >>  8) & 0xFF;
            *row2++ = (value >> 16) & 0xFF;
        }

        /*
         * These values are at the start of the next line, (due
         * to the ++'s above),but they need to be at the start
         * of the line after that.
         */
        lum  += cols;
        lum2 += cols;
        row1 += mod;
        row2 += mod;
    }
}

static void Color32DitherYV12Mod1X( int *colortab, Uint32 *rgb_2_pix,
                                    unsigned char *lum, unsigned char *cr,
                                    unsigned char *cb, unsigned char *out,
                                    int rows, int cols, int mod )
{
    unsigned int* row1;
    unsigned int* row2;
    unsigned char* lum2;
    int x, y;
    int cr_r;
    int crb_g;
    int cb_b;
    int cols_2 = cols / 2;

    row1 = (unsigned int*) out;
    row2 = row1 + cols + mod;
    lum2 = lum + cols;

    mod += cols + mod;

    y = rows / 2;
    while( y-- )
    {
        x = cols_2;
        while( x-- )
        {
            register int L;

            cr_r   = 0*768+256 + colortab[ *cr + 0*256 ];
            crb_g  = 1*768+256 + colortab[ *cr + 1*256 ]
                               + colortab[ *cb + 2*256 ];
            cb_b   = 2*768+256 + colortab[ *cb + 3*256 ];
            ++cr; ++cb;

            L = *lum++;
            *row1++ = (rgb_2_pix[ L + cr_r ] |
                       rgb_2_pix[ L + crb_g ] |
                       rgb_2_pix[ L + cb_b ]);

            L = *lum++;
            *row1++ = (rgb_2_pix[ L + cr_r ] |
                       rgb_2_pix[ L + crb_g ] |
                       rgb_2_pix[ L + cb_b ]);


            /* Now, do second row.  */

            L = *lum2++;
            *row2++ = (rgb_2_pix[ L + cr_r ] |
                       rgb_2_pix[ L + crb_g ] |
                       rgb_2_pix[ L + cb_b ]);

            L = *lum2++;
            *row2++ = (rgb_2_pix[ L + cr_r ] |
                       rgb_2_pix[ L + crb_g ] |
                       rgb_2_pix[ L + cb_b ]);
        }

        /*
         * These values are at the start of the next line, (due
         * to the ++'s above),but they need to be at the start
         * of the line after that.
         */
        lum  += cols;
        lum2 += cols;
        row1 += mod;
        row2 += mod;
    }
}

/*
 * In this function I make use of a nasty trick. The tables have the lower
 * 16 bits replicated in the upper 16. This means I can write ints and get
 * the horisontal doubling for free (almost).
 */
static void Color16DitherYV12Mod2X( int *colortab, Uint32 *rgb_2_pix,
                                    unsigned char *lum, unsigned char *cr,
                                    unsigned char *cb, unsigned char *out,
                                    int rows, int cols, int mod )
{
    unsigned int* row1 = (unsigned int*) out;
    const int next_row = cols+(mod/2);
    unsigned int* row2 = row1 + 2*next_row;
    unsigned char* lum2;
    int x, y;
    int cr_r;
    int crb_g;
    int cb_b;
    int cols_2 = cols / 2;

    lum2 = lum + cols;

    mod = (next_row * 3) + (mod/2);

    y = rows / 2;
    while( y-- )
    {
        x = cols_2;
        while( x-- )
        {
            register int L;

            cr_r   = 0*768+256 + colortab[ *cr + 0*256 ];
            crb_g  = 1*768+256 + colortab[ *cr + 1*256 ]
                               + colortab[ *cb + 2*256 ];
            cb_b   = 2*768+256 + colortab[ *cb + 3*256 ];
            ++cr; ++cb;

            L = *lum++;
            row1[0] = row1[next_row] = (rgb_2_pix[ L + cr_r ] |
                                        rgb_2_pix[ L + crb_g ] |
                                        rgb_2_pix[ L + cb_b ]);
            row1++;

            L = *lum++;
            row1[0] = row1[next_row] = (rgb_2_pix[ L + cr_r ] |
                                        rgb_2_pix[ L + crb_g ] |
                                        rgb_2_pix[ L + cb_b ]);
            row1++;


            /* Now, do second row. */

            L = *lum2++;
            row2[0] = row2[next_row] = (rgb_2_pix[ L + cr_r ] |
                                        rgb_2_pix[ L + crb_g ] |
                                        rgb_2_pix[ L + cb_b ]);
            row2++;

            L = *lum2++;
            row2[0] = row2[next_row] = (rgb_2_pix[ L + cr_r ] |
                                        rgb_2_pix[ L + crb_g ] |
                                        rgb_2_pix[ L + cb_b ]);
            row2++;
        }

        /*
         * These values are at the start of the next line, (due
         * to the ++'s above),but they need to be at the start
         * of the line after that.
         */
        lum  += cols;
        lum2 += cols;
        row1 += mod;
        row2 += mod;
    }
}

static void Color24DitherYV12Mod2X( int *colortab, Uint32 *rgb_2_pix,
                                    unsigned char *lum, unsigned char *cr,
                                    unsigned char *cb, unsigned char *out,
                                    int rows, int cols, int mod )
{
    unsigned int value;
    unsigned char* row1 = out;
    const int next_row = (cols*2 + mod) * 3;
    unsigned char* row2 = row1 + 2*next_row;
    unsigned char* lum2;
    int x, y;
    int cr_r;
    int crb_g;
    int cb_b;
    int cols_2 = cols / 2;

    lum2 = lum + cols;

    mod = next_row*3 + mod*3;

    y = rows / 2;
    while( y-- )
    {
        x = cols_2;
        while( x-- )
        {
            register int L;

            cr_r   = 0*768+256 + colortab[ *cr + 0*256 ];
            crb_g  = 1*768+256 + colortab[ *cr + 1*256 ]
                               + colortab[ *cb + 2*256 ];
            cb_b   = 2*768+256 + colortab[ *cb + 3*256 ];
            ++cr; ++cb;

            L = *lum++;
            value = (rgb_2_pix[ L + cr_r ] |
                     rgb_2_pix[ L + crb_g ] |
                     rgb_2_pix[ L + cb_b ]);
            row1[0+0] = row1[3+0] = row1[next_row+0] = row1[next_row+3+0] =
                     (value      ) & 0xFF;
            row1[0+1] = row1[3+1] = row1[next_row+1] = row1[next_row+3+1] =
                     (value >>  8) & 0xFF;
            row1[0+2] = row1[3+2] = row1[next_row+2] = row1[next_row+3+2] =
                     (value >> 16) & 0xFF;
            row1 += 2*3;

            L = *lum++;
            value = (rgb_2_pix[ L + cr_r ] |
                     rgb_2_pix[ L + crb_g ] |
                     rgb_2_pix[ L + cb_b ]);
            row1[0+0] = row1[3+0] = row1[next_row+0] = row1[next_row+3+0] =
                     (value      ) & 0xFF;
            row1[0+1] = row1[3+1] = row1[next_row+1] = row1[next_row+3+1] =
                     (value >>  8) & 0xFF;
            row1[0+2] = row1[3+2] = row1[next_row+2] = row1[next_row+3+2] =
                     (value >> 16) & 0xFF;
            row1 += 2*3;


            /* Now, do second row. */

            L = *lum2++;
            value = (rgb_2_pix[ L + cr_r ] |
                     rgb_2_pix[ L + crb_g ] |
                     rgb_2_pix[ L + cb_b ]);
            row2[0+0] = row2[3+0] = row2[next_row+0] = row2[next_row+3+0] =
                     (value      ) & 0xFF;
            row2[0+1] = row2[3+1] = row2[next_row+1] = row2[next_row+3+1] =
                     (value >>  8) & 0xFF;
            row2[0+2] = row2[3+2] = row2[next_row+2] = row2[next_row+3+2] =
                     (value >> 16) & 0xFF;
            row2 += 2*3;

            L = *lum2++;
            value = (rgb_2_pix[ L + cr_r ] |
                     rgb_2_pix[ L + crb_g ] |
                     rgb_2_pix[ L + cb_b ]);
            row2[0+0] = row2[3+0] = row2[next_row+0] = row2[next_row+3+0] =
                     (value      ) & 0xFF;
            row2[0+1] = row2[3+1] = row2[next_row+1] = row2[next_row+3+1] =
                     (value >>  8) & 0xFF;
            row2[0+2] = row2[3+2] = row2[next_row+2] = row2[next_row+3+2] =
                     (value >> 16) & 0xFF;
            row2 += 2*3;
        }

        /*
         * These values are at the start of the next line, (due
         * to the ++'s above),but they need to be at the start
         * of the line after that.
         */
        lum  += cols;
        lum2 += cols;
        row1 += mod;
        row2 += mod;
    }
}

static void Color32DitherYV12Mod2X( int *colortab, Uint32 *rgb_2_pix,
                                    unsigned char *lum, unsigned char *cr,
                                    unsigned char *cb, unsigned char *out,
                                    int rows, int cols, int mod )
{
    unsigned int* row1 = (unsigned int*) out;
    const int next_row = cols*2+mod;
    unsigned int* row2 = row1 + 2*next_row;
    unsigned char* lum2;
    int x, y;
    int cr_r;
    int crb_g;
    int cb_b;
    int cols_2 = cols / 2;

    lum2 = lum + cols;

    mod = (next_row * 3) + mod;

    y = rows / 2;
    while( y-- )
    {
        x = cols_2;
        while( x-- )
        {
            register int L;

            cr_r   = 0*768+256 + colortab[ *cr + 0*256 ];
            crb_g  = 1*768+256 + colortab[ *cr + 1*256 ]
                               + colortab[ *cb + 2*256 ];
            cb_b   = 2*768+256 + colortab[ *cb + 3*256 ];
            ++cr; ++cb;

            L = *lum++;
            row1[0] = row1[1] = row1[next_row] = row1[next_row+1] =
                                       (rgb_2_pix[ L + cr_r ] |
                                        rgb_2_pix[ L + crb_g ] |
                                        rgb_2_pix[ L + cb_b ]);
            row1 += 2;

            L = *lum++;
            row1[0] = row1[1] = row1[next_row] = row1[next_row+1] =
                                       (rgb_2_pix[ L + cr_r ] |
                                        rgb_2_pix[ L + crb_g ] |
                                        rgb_2_pix[ L + cb_b ]);
            row1 += 2;


            /* Now, do second row. */

            L = *lum2++;
            row2[0] = row2[1] = row2[next_row] = row2[next_row+1] =
                                       (rgb_2_pix[ L + cr_r ] |
                                        rgb_2_pix[ L + crb_g ] |
                                        rgb_2_pix[ L + cb_b ]);
            row2 += 2;

            L = *lum2++;
            row2[0] = row2[1] = row2[next_row] = row2[next_row+1] =
                                       (rgb_2_pix[ L + cr_r ] |
                                        rgb_2_pix[ L + crb_g ] |
                                        rgb_2_pix[ L + cb_b ]);
            row2 += 2;
        }

        /*
         * These values are at the start of the next line, (due
         * to the ++'s above),but they need to be at the start
         * of the line after that.
         */
        lum  += cols;
        lum2 += cols;
        row1 += mod;
        row2 += mod;
    }
}

static void Color16DitherYUY2Mod1X( int *colortab, Uint32 *rgb_2_pix,
                                    unsigned char *lum, unsigned char *cr,
                                    unsigned char *cb, unsigned char *out,
                                    int rows, int cols, int mod )
{
    unsigned short* row;
    int x, y;
    int cr_r;
    int crb_g;
    int cb_b;
    int cols_2 = cols / 2;

    row = (unsigned short*) out;

    y = rows;
    while( y-- )
    {
        x = cols_2;
        while( x-- )
        {
            register int L;

            cr_r   = 0*768+256 + colortab[ *cr + 0*256 ];
            crb_g  = 1*768+256 + colortab[ *cr + 1*256 ]
                               + colortab[ *cb + 2*256 ];
            cb_b   = 2*768+256 + colortab[ *cb + 3*256 ];
            cr += 4; cb += 4;

            L = *lum; lum += 2;
            *row++ = (unsigned short)(rgb_2_pix[ L + cr_r ] |
                                      rgb_2_pix[ L + crb_g ] |
                                      rgb_2_pix[ L + cb_b ]);

            L = *lum; lum += 2;
            *row++ = (unsigned short)(rgb_2_pix[ L + cr_r ] |
                                      rgb_2_pix[ L + crb_g ] |
                                      rgb_2_pix[ L + cb_b ]);

        }

        row += mod;
    }
}

static void Color24DitherYUY2Mod1X( int *colortab, Uint32 *rgb_2_pix,
                                    unsigned char *lum, unsigned char *cr,
                                    unsigned char *cb, unsigned char *out,
                                    int rows, int cols, int mod )
{
    unsigned int value;
    unsigned char* row;
    int x, y;
    int cr_r;
    int crb_g;
    int cb_b;
    int cols_2 = cols / 2;

    row = (unsigned char*) out;
    mod *= 3;
    y = rows;
    while( y-- )
    {
        x = cols_2;
        while( x-- )
        {
            register int L;

            cr_r   = 0*768+256 + colortab[ *cr + 0*256 ];
            crb_g  = 1*768+256 + colortab[ *cr + 1*256 ]
                               + colortab[ *cb + 2*256 ];
            cb_b   = 2*768+256 + colortab[ *cb + 3*256 ];
            cr += 4; cb += 4;

            L = *lum; lum += 2;
            value = (rgb_2_pix[ L + cr_r ] |
                     rgb_2_pix[ L + crb_g ] |
                     rgb_2_pix[ L + cb_b ]);
            *row++ = (value      ) & 0xFF;
            *row++ = (value >>  8) & 0xFF;
            *row++ = (value >> 16) & 0xFF;

            L = *lum; lum += 2;
            value = (rgb_2_pix[ L + cr_r ] |
                     rgb_2_pix[ L + crb_g ] |
                     rgb_2_pix[ L + cb_b ]);
            *row++ = (value      ) & 0xFF;
            *row++ = (value >>  8) & 0xFF;
            *row++ = (value >> 16) & 0xFF;

        }
        row += mod;
    }
}

static void Color32DitherYUY2Mod1X( int *colortab, Uint32 *rgb_2_pix,
                                    unsigned char *lum, unsigned char *cr,
                                    unsigned char *cb, unsigned char *out,
                                    int rows, int cols, int mod )
{
    unsigned int* row;
    int x, y;
    int cr_r;
    int crb_g;
    int cb_b;
    int cols_2 = cols / 2;

    row = (unsigned int*) out;
    y = rows;
    while( y-- )
    {
        x = cols_2;
        while( x-- )
        {
            register int L;

            cr_r   = 0*768+256 + colortab[ *cr + 0*256 ];
            crb_g  = 1*768+256 + colortab[ *cr + 1*256 ]
                               + colortab[ *cb + 2*256 ];
            cb_b   = 2*768+256 + colortab[ *cb + 3*256 ];
            cr += 4; cb += 4;

            L = *lum; lum += 2;
            *row++ = (rgb_2_pix[ L + cr_r ] |
                       rgb_2_pix[ L + crb_g ] |
                       rgb_2_pix[ L + cb_b ]);

            L = *lum; lum += 2;
            *row++ = (rgb_2_pix[ L + cr_r ] |
                       rgb_2_pix[ L + crb_g ] |
                       rgb_2_pix[ L + cb_b ]);


        }
        row += mod;
    }
}

/*
 * In this function I make use of a nasty trick. The tables have the lower
 * 16 bits replicated in the upper 16. This means I can write ints and get
 * the horisontal doubling for free (almost).
 */
static void Color16DitherYUY2Mod2X( int *colortab, Uint32 *rgb_2_pix,
                                    unsigned char *lum, unsigned char *cr,
                                    unsigned char *cb, unsigned char *out,
                                    int rows, int cols, int mod )
{
    unsigned int* row = (unsigned int*) out;
    const int next_row = cols+(mod/2);
    int x, y;
    int cr_r;
    int crb_g;
    int cb_b;
    int cols_2 = cols / 2;

    y = rows;
    while( y-- )
    {
        x = cols_2;
        while( x-- )
        {
            register int L;

            cr_r   = 0*768+256 + colortab[ *cr + 0*256 ];
            crb_g  = 1*768+256 + colortab[ *cr + 1*256 ]
                               + colortab[ *cb + 2*256 ];
            cb_b   = 2*768+256 + colortab[ *cb + 3*256 ];
            cr += 4; cb += 4;

            L = *lum; lum += 2;
            row[0] = row[next_row] = (rgb_2_pix[ L + cr_r ] |
                                        rgb_2_pix[ L + crb_g ] |
                                        rgb_2_pix[ L + cb_b ]);
            row++;

            L = *lum; lum += 2;
            row[0] = row[next_row] = (rgb_2_pix[ L + cr_r ] |
                                        rgb_2_pix[ L + crb_g ] |
                                        rgb_2_pix[ L + cb_b ]);
            row++;

        }
        row += next_row;
    }
}

static void Color24DitherYUY2Mod2X( int *colortab, Uint32 *rgb_2_pix,
                                    unsigned char *lum, unsigned char *cr,
                                    unsigned char *cb, unsigned char *out,
                                    int rows, int cols, int mod )
{
    unsigned int value;
    unsigned char* row = out;
    const int next_row = (cols*2 + mod) * 3;
    int x, y;
    int cr_r;
    int crb_g;
    int cb_b;
    int cols_2 = cols / 2;
    y = rows;
    while( y-- )
    {
        x = cols_2;
        while( x-- )
        {
            register int L;

            cr_r   = 0*768+256 + colortab[ *cr + 0*256 ];
            crb_g  = 1*768+256 + colortab[ *cr + 1*256 ]
                               + colortab[ *cb + 2*256 ];
            cb_b   = 2*768+256 + colortab[ *cb + 3*256 ];
            cr += 4; cb += 4;

            L = *lum; lum += 2;
            value = (rgb_2_pix[ L + cr_r ] |
                     rgb_2_pix[ L + crb_g ] |
                     rgb_2_pix[ L + cb_b ]);
            row[0+0] = row[3+0] = row[next_row+0] = row[next_row+3+0] =
                     (value      ) & 0xFF;
            row[0+1] = row[3+1] = row[next_row+1] = row[next_row+3+1] =
                     (value >>  8) & 0xFF;
            row[0+2] = row[3+2] = row[next_row+2] = row[next_row+3+2] =
                     (value >> 16) & 0xFF;
            row += 2*3;

            L = *lum; lum += 2;
            value = (rgb_2_pix[ L + cr_r ] |
                     rgb_2_pix[ L + crb_g ] |
                     rgb_2_pix[ L + cb_b ]);
            row[0+0] = row[3+0] = row[next_row+0] = row[next_row+3+0] =
                     (value      ) & 0xFF;
            row[0+1] = row[3+1] = row[next_row+1] = row[next_row+3+1] =
                     (value >>  8) & 0xFF;
            row[0+2] = row[3+2] = row[next_row+2] = row[next_row+3+2] =
                     (value >> 16) & 0xFF;
            row += 2*3;

        }
        row += next_row;
    }
}

static void Color32DitherYUY2Mod2X( int *colortab, Uint32 *rgb_2_pix,
                                    unsigned char *lum, unsigned char *cr,
                                    unsigned char *cb, unsigned char *out,
                                    int rows, int cols, int mod )
{
    unsigned int* row = (unsigned int*) out;
    const int next_row = cols*2+mod;
    int x, y;
    int cr_r;
    int crb_g;
    int cb_b;
    int cols_2 = cols / 2;
    mod+=mod;
    y = rows;
    while( y-- )
    {
        x = cols_2;
        while( x-- )
        {
            register int L;

            cr_r   = 0*768+256 + colortab[ *cr + 0*256 ];
            crb_g  = 1*768+256 + colortab[ *cr + 1*256 ]
                               + colortab[ *cb + 2*256 ];
            cb_b   = 2*768+256 + colortab[ *cb + 3*256 ];
            cr += 4; cb += 4;

            L = *lum; lum += 2;
            row[0] = row[1] = row[next_row] = row[next_row+1] =
                                       (rgb_2_pix[ L + cr_r ] |
                                        rgb_2_pix[ L + crb_g ] |
                                        rgb_2_pix[ L + cb_b ]);
            row += 2;

            L = *lum; lum += 2;
            row[0] = row[1] = row[next_row] = row[next_row+1] =
                                       (rgb_2_pix[ L + cr_r ] |
                                        rgb_2_pix[ L + crb_g ] |
                                        rgb_2_pix[ L + cb_b ]);
            row += 2;


        }

        row += next_row;
    }
}

/*
 * How many 1 bits are there in the Uint32.
 * Low performance, do not call often.
 */
static int number_of_bits_set( Uint32 a )
{
    if(!a) return 0;
    if(a & 1) return 1 + number_of_bits_set(a >> 1);
    return(number_of_bits_set(a >> 1));
}

/*
 * How many 0 bits are there at least significant end of Uint32.
 * Low performance, do not call often.
 */
static int free_bits_at_bottom( Uint32 a )
{
      /* assume char is 8 bits */
    if(!a) return sizeof(Uint32) * 8;
    if(((Sint32)a) & 1l) return 0;
    return 1 + free_bits_at_bottom ( a >> 1);
}


SDL_Overlay *SDL_CreateYUV_SW(_THIS, int width, int height, Uint32 format, SDL_Surface *display)
{
	SDL_Overlay *overlay;
	struct private_yuvhwdata *swdata;
	int *Cr_r_tab;
	int *Cr_g_tab;
	int *Cb_g_tab;
	int *Cb_b_tab;
	Uint32 *r_2_pix_alloc;
	Uint32 *g_2_pix_alloc;
	Uint32 *b_2_pix_alloc;
	int i;
	int CR, CB;
	Uint32 Rmask, Gmask, Bmask;

	/* Only RGB packed pixel conversion supported */
	if ( (display->format->BytesPerPixel != 2) &&
	     (display->format->BytesPerPixel != 3) &&
	     (display->format->BytesPerPixel != 4) ) {
		SDL_SetError("Can't use YUV data on non 16/24/32 bit surfaces");
		return(NULL);
	}

	/* Verify that we support the format */
	switch (format) {
	    case SDL_YV12_OVERLAY:
	    case SDL_IYUV_OVERLAY:
	    case SDL_YUY2_OVERLAY:
	    case SDL_UYVY_OVERLAY:
	    case SDL_YVYU_OVERLAY:
		break;
	    default:
		SDL_SetError("Unsupported YUV format");
		return(NULL);
	}

	/* Create the overlay structure */
	overlay = (SDL_Overlay *)SDL_malloc(sizeof *overlay);
	if ( overlay == NULL ) {
		SDL_OutOfMemory();
		return(NULL);
	}
	SDL_memset(overlay, 0, (sizeof *overlay));

	/* Fill in the basic members */
	overlay->format = format;
	overlay->w = width;
	overlay->h = height;

	/* Set up the YUV surface function structure */
	overlay->hwfuncs = &sw_yuvfuncs;

	/* Create the pixel data and lookup tables */
	swdata = (struct private_yuvhwdata *)SDL_malloc(sizeof *swdata);
	overlay->hwdata = swdata;
	if ( swdata == NULL ) {
		SDL_OutOfMemory();
		SDL_FreeYUVOverlay(overlay);
		return(NULL);
	}
	swdata->stretch = NULL;
	swdata->display = display;
	swdata->pixels = (Uint8 *) SDL_malloc(width*height*2);
	swdata->colortab = (int *)SDL_malloc(4*256*sizeof(int));
	Cr_r_tab = &swdata->colortab[0*256];
	Cr_g_tab = &swdata->colortab[1*256];
	Cb_g_tab = &swdata->colortab[2*256];
	Cb_b_tab = &swdata->colortab[3*256];
	swdata->rgb_2_pix = (Uint32 *)SDL_malloc(3*768*sizeof(Uint32));
	r_2_pix_alloc = &swdata->rgb_2_pix[0*768];
	g_2_pix_alloc = &swdata->rgb_2_pix[1*768];
	b_2_pix_alloc = &swdata->rgb_2_pix[2*768];
	if ( ! swdata->pixels || ! swdata->colortab || ! swdata->rgb_2_pix ) {
		SDL_OutOfMemory();
		SDL_FreeYUVOverlay(overlay);
		return(NULL);
	}

	/* Generate the tables for the display surface */
	for (i=0; i<256; i++) {
		/* Gamma correction (luminescence table) and chroma correction
		   would be done here.  See the Berkeley mpeg_play sources.
		*/
		CB = CR = (i-128);
		Cr_r_tab[i] = (int) ( (0.419/0.299) * CR);
		Cr_g_tab[i] = (int) (-(0.299/0.419) * CR);
		Cb_g_tab[i] = (int) (-(0.114/0.331) * CB); 
		Cb_b_tab[i] = (int) ( (0.587/0.331) * CB);
	}

	/* 
	 * Set up entries 0-255 in rgb-to-pixel value tables.
	 */
	Rmask = display->format->Rmask;
	Gmask = display->format->Gmask;
	Bmask = display->format->Bmask;
	for ( i=0; i<256; ++i ) {
		r_2_pix_alloc[i+256] = i >> (8 - number_of_bits_set(Rmask));
		r_2_pix_alloc[i+256] <<= free_bits_at_bottom(Rmask);
		g_2_pix_alloc[i+256] = i >> (8 - number_of_bits_set(Gmask));
		g_2_pix_alloc[i+256] <<= free_bits_at_bottom(Gmask);
		b_2_pix_alloc[i+256] = i >> (8 - number_of_bits_set(Bmask));
		b_2_pix_alloc[i+256] <<= free_bits_at_bottom(Bmask);
	}

	/*
	 * If we have 16-bit output depth, then we double the value
	 * in the top word. This means that we can write out both
	 * pixels in the pixel doubling mode with one op. It is 
	 * harmless in the normal case as storing a 32-bit value
	 * through a short pointer will lose the top bits anyway.
	 */
	if( display->format->BytesPerPixel == 2 ) {
		for ( i=0; i<256; ++i ) {
			r_2_pix_alloc[i+256] |= (r_2_pix_alloc[i+256]) << 16;
			g_2_pix_alloc[i+256] |= (g_2_pix_alloc[i+256]) << 16;
			b_2_pix_alloc[i+256] |= (b_2_pix_alloc[i+256]) << 16;
		}
	}

	/*
	 * Spread out the values we have to the rest of the array so that
	 * we do not need to check for overflow.
	 */
	for ( i=0; i<256; ++i ) {
		r_2_pix_alloc[i] = r_2_pix_alloc[256];
		r_2_pix_alloc[i+512] = r_2_pix_alloc[511];
		g_2_pix_alloc[i] = g_2_pix_alloc[256];
		g_2_pix_alloc[i+512] = g_2_pix_alloc[511];
		b_2_pix_alloc[i] = b_2_pix_alloc[256];
		b_2_pix_alloc[i+512] = b_2_pix_alloc[511];
	}

	/* You have chosen wisely... */
	switch (format) {
	    case SDL_YV12_OVERLAY:
	    case SDL_IYUV_OVERLAY:
		if ( display->format->BytesPerPixel == 2 ) {
#if 0 /*defined(__GNUC__) && defined(__i386__) && SDL_ASSEMBLY_ROUTINES*/
			/* inline assembly functions */
			if ( SDL_HasMMX() && (Rmask == 0xF800) &&
			                     (Gmask == 0x07E0) &&
				             (Bmask == 0x001F) &&
			                     (width & 15) == 0) {
/*printf("Using MMX 16-bit 565 dither\n");*/
				swdata->Display1X = Color565DitherYV12MMX1X;
			} else {
/*printf("Using C 16-bit dither\n");*/
				swdata->Display1X = Color16DitherYV12Mod1X;
			}
#else
			swdata->Display1X = Color16DitherYV12Mod1X;
#endif
			swdata->Display2X = Color16DitherYV12Mod2X;
		}
		if ( display->format->BytesPerPixel == 3 ) {
			swdata->Display1X = Color24DitherYV12Mod1X;
			swdata->Display2X = Color24DitherYV12Mod2X;
		}
		if ( display->format->BytesPerPixel == 4 ) {
#if 0 /*defined(__GNUC__) && defined(__i386__) && SDL_ASSEMBLY_ROUTINES*/
			/* inline assembly functions */
			if ( SDL_HasMMX() && (Rmask == 0x00FF0000) &&
			                     (Gmask == 0x0000FF00) &&
				             (Bmask == 0x000000FF) && 
			                     (width & 15) == 0) {
/*printf("Using MMX 32-bit dither\n");*/
				swdata->Display1X = ColorRGBDitherYV12MMX1X;
			} else {
/*printf("Using C 32-bit dither\n");*/
				swdata->Display1X = Color32DitherYV12Mod1X;
			}
#else
			swdata->Display1X = Color32DitherYV12Mod1X;
#endif
			swdata->Display2X = Color32DitherYV12Mod2X;
		}
		break;
	    case SDL_YUY2_OVERLAY:
	    case SDL_UYVY_OVERLAY:
	    case SDL_YVYU_OVERLAY:
		if ( display->format->BytesPerPixel == 2 ) {
			swdata->Display1X = Color16DitherYUY2Mod1X;
			swdata->Display2X = Color16DitherYUY2Mod2X;
		}
		if ( display->format->BytesPerPixel == 3 ) {
			swdata->Display1X = Color24DitherYUY2Mod1X;
			swdata->Display2X = Color24DitherYUY2Mod2X;
		}
		if ( display->format->BytesPerPixel == 4 ) {
			swdata->Display1X = Color32DitherYUY2Mod1X;
			swdata->Display2X = Color32DitherYUY2Mod2X;
		}
		break;
	    default:
		/* We should never get here (caught above) */
		break;
	}

	/* Find the pitch and offset values for the overlay */
	overlay->pitches = swdata->pitches;
	overlay->pixels = swdata->planes;
	switch (format) {
	    case SDL_YV12_OVERLAY:
	    case SDL_IYUV_OVERLAY:
		overlay->pitches[0] = overlay->w;
		overlay->pitches[1] = overlay->pitches[0] / 2;
		overlay->pitches[2] = overlay->pitches[0] / 2;
	        overlay->pixels[0] = swdata->pixels;
	        overlay->pixels[1] = overlay->pixels[0] +
		                     overlay->pitches[0] * overlay->h;
	        overlay->pixels[2] = overlay->pixels[1] +
		                     overlay->pitches[1] * overlay->h / 2;
		overlay->planes = 3;
		break;
	    case SDL_YUY2_OVERLAY:
	    case SDL_UYVY_OVERLAY:
	    case SDL_YVYU_OVERLAY:
		overlay->pitches[0] = overlay->w*2;
	        overlay->pixels[0] = swdata->pixels;
		overlay->planes = 1;
		break;
	    default:
		/* We should never get here (caught above) */
		break;
	}

	/* We're all done.. */
	return(overlay);
}

int SDL_LockYUV_SW(_THIS, SDL_Overlay *overlay)
{
	return(0);
}

void SDL_UnlockYUV_SW(_THIS, SDL_Overlay *overlay)
{
	return;
}

int SDL_DisplayYUV_SW(_THIS, SDL_Overlay *overlay, SDL_Rect *dstrect)
{
	struct private_yuvhwdata *swdata;
	SDL_Surface *stretch;
	SDL_Surface *display;
	int scale_2x;
	Uint8 *lum, *Cr, *Cb;
	Uint8 *dst;
	int mod;

	swdata = overlay->hwdata;
	scale_2x = 0;
	stretch = 0;
	if ( (overlay->w != dstrect->w) || (overlay->h != dstrect->h) ) {
		if ( (dstrect->w == 2*overlay->w) &&
		     (dstrect->h == 2*overlay->h) ) {
			scale_2x = 1;
		} else {
			if ( ! swdata->stretch ) {
				display = swdata->display;
				swdata->stretch = SDL_CreateRGBSurface(
					SDL_SWSURFACE,
					overlay->w, overlay->h,
					display->format->BitsPerPixel,
					display->format->Rmask,
					display->format->Gmask,
					display->format->Bmask, 0);
				if ( ! swdata->stretch ) {
					return(-1);
				}
			}
			stretch = swdata->stretch;
		}
	}

	if ( stretch ) {
		display = stretch;
	} else {
		display = swdata->display;
	}
	switch (overlay->format) {
	    case SDL_YV12_OVERLAY:
		lum = overlay->pixels[0];
		Cr =  overlay->pixels[1];
		Cb =  overlay->pixels[2];
		break;
	    case SDL_IYUV_OVERLAY:
		lum = overlay->pixels[0];
		Cr =  overlay->pixels[2];
		Cb =  overlay->pixels[1];
		break;
	    case SDL_YUY2_OVERLAY:
		lum = overlay->pixels[0];
		Cr = lum + 3;
		Cb = lum + 1;
		break;
	    case SDL_UYVY_OVERLAY:
		lum = overlay->pixels[0]+1;
		Cr = lum + 1;
		Cb = lum - 1;
		break;
	    case SDL_YVYU_OVERLAY:
		lum = overlay->pixels[0];
		Cr = lum + 1;
		Cb = lum + 3;
		break;
	    default:
		SDL_SetError("Unsupported YUV format in blit");
		return(-1);
	}
	if ( SDL_MUSTLOCK(display) ) {
        	if ( SDL_LockSurface(display) < 0 ) {
			return(-1);
		}
	}
	if ( stretch ) {
		dst = (Uint8 *)stretch->pixels;
	} else {
		dst = (Uint8 *)display->pixels
			+ dstrect->x * display->format->BytesPerPixel
			+ dstrect->y * display->pitch;
	}
	mod = (display->pitch / display->format->BytesPerPixel);

	if ( scale_2x ) {
		mod -= (overlay->w * 2);
		swdata->Display2X(swdata->colortab, swdata->rgb_2_pix,
		                  lum, Cr, Cb, dst, overlay->h, overlay->w,mod);
	} else {
		mod -= overlay->w;
		swdata->Display1X(swdata->colortab, swdata->rgb_2_pix,
		                  lum, Cr, Cb, dst, overlay->h, overlay->w,mod);
	}
	if ( SDL_MUSTLOCK(display) ) {
		SDL_UnlockSurface(display);
	}
	if ( stretch ) {
		display = swdata->display;
		SDL_SoftStretch(stretch, NULL, display, dstrect);
	}
	SDL_UpdateRects(display, 1, dstrect);

	return(0);
}

void SDL_FreeYUV_SW(_THIS, SDL_Overlay *overlay)
{
	struct private_yuvhwdata *swdata;

	swdata = overlay->hwdata;
	if ( swdata ) {
		if ( swdata->stretch ) {
			SDL_FreeSurface(swdata->stretch);
		}
		if ( swdata->pixels ) {
			SDL_free(swdata->pixels);
		}
		if ( swdata->colortab ) {
			SDL_free(swdata->colortab);
		}
		if ( swdata->rgb_2_pix ) {
			SDL_free(swdata->rgb_2_pix);
		}
		SDL_free(swdata);
	}
}