displaylin.cpp

这是在PCA下的基于IPP库示例代码例子,在网上下了IPP的库之后,设置相关参数就可以编译该代码.

/* ////////////////////////////////////////////////////////////////////////
//
//                  INTEL CORPORATION PROPRIETARY INFORMATION
//     This software is supplied under the terms of a license agreement or
//     nondisclosure agreement with Intel Corporation and may not be copied
//     or disclosed except in accordance with the terms of that agreement.
//          Copyright(c) 2002-2005 Intel Corporation. All Rights Reserved.
//
//
//
*/

#if (defined SYSLIN) && (!defined XSCALE)

#include "X11/Xlib.h"
#include "X11/Xutil.h"
#include "malloc.h"
#include "string.h"

#include "stdio.h"

static void Dither(
    unsigned char *dst,
    unsigned char *src,
    int width,
    int height,
    int depth,
    unsigned int redMask,
    unsigned int greenMask,
    unsigned int blueMask );

inline float ScaleFactor( unsigned int bitMask )
{
    int i = 0;

    while(!((bitMask >> i) & 1))
        i++;

    while(((bitMask >> i) & 1))
        i++;

    return (i <= 8) ? 1.0 / (1 << (8 - i)) : 1 << (i - 8);
}

inline unsigned int ByteOffset(unsigned int bitMask)
{
    switch (bitMask)
    {
    case 0xFF000000: return 0;
    case 0x00FF0000: return 1;
    case 0x0000FF00: return 2;
    //case 0x000000FF: return 3;
    default:
        return 3;
    }
}


int DisplayPixMap( unsigned char *pixMap,
                   const int      width,
                   const int      height,
                   const char    *jp2FileName )
{
    XImage *xImage;
    XSetWindowAttributes xswa;
    Window win;
    GC gc;
    Display *dsp = XOpenDisplay(NULL);
    int screenNumber = DefaultScreen(dsp);
    Visual *visual = DefaultVisual(dsp, screenNumber);
    int defaultDepth = DefaultDepth(dsp, screenNumber);
    char *ditheredImage;
    char windowTitle[300] = "JPEG2000 Viewer - ";

    unsigned int mask = CWBackPixel | CWBorderPixel;

    if (defaultDepth == 32 || defaultDepth == 24 || defaultDepth == 16) {
        mask |= CWColormap;
        xswa.colormap = XCreateColormap (dsp, DefaultRootWindow(dsp), visual, AllocNone);
    }

    xswa.background_pixel = WhitePixel(dsp, screenNumber);
    xswa.border_pixel = BlackPixel(dsp, screenNumber);

    win = XCreateWindow(dsp, DefaultRootWindow(dsp), 0, 0, width, height, 1,
        defaultDepth, InputOutput, visual, mask, &xswa);
    if(!win)
        return 1;

    gc = XCreateGC(dsp, win, 0, NULL);
    if(!gc)
        return 1;

    XMapWindow(dsp, win);
    XSelectInput(dsp, win, ExposureMask);

    strcat(windowTitle, jp2FileName);
    XSetStandardProperties(dsp, win, windowTitle, NULL, None, NULL, 0, NULL);

    ditheredImage = (char *)memalign(   4, width * height *
        (  defaultDepth == 24 ? 4 : ( defaultDepth == 15 ? 2 : (defaultDepth / 8) )  )   );

    Dither((unsigned char *)ditheredImage, (unsigned char *)pixMap, width, height, defaultDepth,
        visual->red_mask, visual->green_mask, visual->blue_mask);

    xImage = XCreateImage(dsp, visual, defaultDepth, ZPixmap, 0, (char *)ditheredImage, width, height,
        defaultDepth == 24 ? 32 : (defaultDepth == 15 ? 16 : defaultDepth), 0);

    if(!xImage)
        return 1;

    for(;;)
    {
        XEvent x_event;
        XNextEvent(dsp, &x_event);
        switch (x_event.type)
        {
        case Expose:
            XPutImage(dsp, win, gc, xImage, 0, 0, 0, 0, width, height);
            XFlush(dsp);
            break;
        }
    }

    free(ditheredImage);
    return 0;
}

static void Dither(
    unsigned char *dst,
    unsigned char *src,
    int width,
    int height,
    int depth,
    unsigned int redMask,
    unsigned int greenMask,
    unsigned int blueMask)
{
    float rScaleFactor = ScaleFactor(redMask);
    float gScaleFactor = ScaleFactor(greenMask);
    float bScaleFactor = ScaleFactor(blueMask);
    int lineStep = ((width * 3) + 3) & 0xFFFFFFFC;

    unsigned char r, g, b;
    unsigned int pixel;
    int x, y;

    switch(depth)
    {
    case 8:
        for(y = 0; y < height; y++)
        {
            for(x = 0; x < width; x++)
            {
                b = src[lineStep * (height - y - 1) + 3 * x + 0];
                g = src[lineStep * (height - y - 1) + 3 * x + 1];
                r = src[lineStep * (height - y - 1) + 3 * x + 2];

                pixel = (((unsigned int)(r * rScaleFactor)) & redMask  ) +
                        (((unsigned int)(g * gScaleFactor)) & greenMask) +
                        (((unsigned int)(b * bScaleFactor)) & blueMask );

                dst[width * y + x] = pixel;
            }
        }
        break;
    case 16:
        for(y = 0; y < height; y++)
        {
            for(x = 0; x < width; x++)
            {
                b = src[lineStep * (height - y - 1) + 3 * x + 0];
                g = src[lineStep * (height - y - 1) + 3 * x + 1];
                r = src[lineStep * (height - y - 1) + 3 * x + 2];

                pixel = (((unsigned int)(r * rScaleFactor)) & redMask  ) +
                        (((unsigned int)(g * gScaleFactor)) & greenMask) +
                        (((unsigned int)(b * bScaleFactor)) & blueMask );

                ((unsigned short *)dst)[width * y + x] = pixel;
            }
        }
        break;
    case 24:
    case 32:
        {
            unsigned int rOffset = ByteOffset(redMask);
            unsigned int gOffset = ByteOffset(greenMask);
            unsigned int bOffset = ByteOffset(blueMask);
            
            for(y = 0; y < height; y++)
            {
                for(x = 0; x < width; x++)
                {
                    dst[4 * (width * y + x) + bOffset] = src[lineStep * (height - y - 1) + 3 * x + 0];
                    dst[4 * (width * y + x) + gOffset] = src[lineStep * (height - y - 1) + 3 * x + 1];
                    dst[4 * (width * y + x) + rOffset] = src[lineStep * (height - y - 1) + 3 * x + 2];
                }
            }
        }

        break;
    default:
        break;
    }
}


#endif // SYSLIN