一组rgb转换函数，支持rgb565/rgb888/xrgb8888之间的数据转换

一组rgb转换函数，支持rgb565/rgb888/xrgb8888之间的数据转换

 

mybmp.h

/********************************************************************
    created:    2012/04/07
    filename:   mybmp.h
    author:

    purpose:
*********************************************************************/

#ifndef _mybmp_h__
#define _mybmp_h__
//-------------------------------------------------------------------

#ifdef __cplusplus
extern "C" {
#endif

#define UpAlign4(n) (((n) + 3) & ~3)
#define UpAlign8(n) (((n) + 7) & ~7)

//拷贝数据
void rgb_copy(const void * psrc, void * pdst, int sw, int sh, int dw, int dh, int bpp);
void rbg565_copy(const void * psrc, void * pdst, int sw, int sh, int dw, int dh);
void rbg888_copy(const void * psrc, void * pdst, int sw, int sh, int dw, int dh);
void rbgx8888_copy(const void * psrc, void * pdst, int sw, int sh, int dw, int dh);

//行数据翻转
void line_reversal(void * pdata, int w, int h, int bpp);
void rgb565_line_reversal(void * p565, int w, int h);
void rgb888_line_reversal(void * p888, int w, int h);
void rgbx8888_line_reversal(void * p8888, int w, int h);

//转换
typedef void * (* RGB_CONVERT_FUN)(const void * psrc, int w, int h);
void * rgb565_to_rgb888_buffer(const void * psrc, int w, int h);
void * rgb888_to_rgb565_buffer(const void * psrc, int w, int h);
void * rgb565_to_rgbx8888_buffer(const void * psrc, int w, int h);
void * rgbx8888_to_rgb565_buffer(const void * psrc, int w, int h);
void * rgb888_to_rgbx8888_buffer(const void * psrc, int w, int h);
void * rgbx8888_to_rgb888_buffer(const void * psrc, int w, int h);
RGB_CONVERT_FUN get_convert_func(int frombpp, int tobpp);

#ifdef __cplusplus
};
#endif

//-------------------------------------------------------------------
#endif // #ifndef _mybmp_h__

rgb_convert.c

/********************************************************************
    created:    2012/05/19
    filename:   rgb_convert.c
    author:

    purpose:
*********************************************************************/

//-------------------------------------------------------------------
#include <stdlib.h>
#include <stdio.h>
#include <memory.h>
#include "mybmp.h"

//-------------------------------------------------------------------
//拷贝
void rgb_copy(const void * psrc, void * pdst, int sw, int sh, int dw, int dh, int bpp)
{
    int bytes = UpAlign8(bpp) >> 3; // bpp / 8
    int srclinesize = UpAlign4(sw * bytes);
    int dstlinesize = UpAlign4(dw * bytes);
    int copylinesize = srclinesize < dstlinesize ? srclinesize : dstlinesize;
    int copylines = sh < dh ? sh : dh;

    const unsigned char * psrcline = (const unsigned char *)psrc;
    const unsigned char * pend = psrcline + copylines * srclinesize;
    unsigned char * pdstline = (unsigned char *)pdst;

    while (psrcline < pend) {
        memcpy(pdstline, psrcline, copylinesize);
        psrcline += srclinesize;
        pdstline += dstlinesize;
    }
}

void rbg565_copy(const void * psrc, void * pdst, int sw, int sh, int dw, int dh)
{
    rgb_copy(psrc, pdst, sw, sh, dw, dh, 16);
}

void rbg888_copy(const void * psrc, void * pdst, int sw, int sh, int dw, int dh)
{
    rgb_copy(psrc, pdst, sw, sh, dw, dh, 24);
}

void rbgx8888_copy(const void * psrc, void * pdst, int sw, int sh, int dw, int dh)
{
    rgb_copy(psrc, pdst, sw, sh, dw, dh, 32);
}

//-------------------------------------------------------------------
//行数据翻转
void line_reversal(void * pdata, int w, int h, int bpp)
{
    int bytes     = UpAlign8(bpp) >> 3; // bpp / 8
    int linesize  = UpAlign4(w * bytes);//4的整数倍
    int copylines = h >> 1;

    int i;
    unsigned char * pline = NULL;
    unsigned char * pline1 = NULL;
    unsigned char * linebuffer = NULL;

    if (pdata && w > 0 && h > 1) {//至少两行才需要翻转
        linebuffer = (unsigned char *)malloc(linesize);
        if (linebuffer) {
            pline  = (unsigned char *)pdata;
            pline1 = (unsigned char *)pdata + linesize * (h - 1);
            for (i = 0; i < copylines; i++) {
                memcpy(linebuffer, pline, linesize);
                memcpy(pline, pline1, linesize);
                memcpy(pline1, linebuffer, linesize);
                pline  += linesize;
                pline1 -= linesize;
            }
            free(linebuffer);
        }
    }
}

void rgb565_line_reversal(void * p565, int w, int h)
{
    line_reversal(p565, w, h, 16);
}

void rgb888_line_reversal(void * p888, int w, int h)
{
    line_reversal(p888, w, h, 24);
}

void rgbx8888_line_reversal(void * p8888, int w, int h)
{
    line_reversal(p8888, w, h, 32);
}

//-------------------------------------------------------------------
//转换
static int rgb565_to_rgb888(const void * psrc, int w, int h, void * pdst)
{
    int srclinesize = UpAlign4(w * 2);
    int dstlinesize = UpAlign4(w * 3);

    const unsigned char  * psrcline;
    const unsigned short * psrcdot;
    unsigned char  * pdstline;
    unsigned char  * pdstdot;

    int i,j;

    if (!psrc || !pdst || w <= 0 || h <= 0) {
        printf("rgb565_to_rgb888 : parameter error\n");
        return -1;
    }

    psrcline = (const unsigned char *)psrc;
    pdstline = (unsigned char *)pdst;
    for (i=0; i<h; i++) {
        psrcdot = (const unsigned short *)psrcline;
        pdstdot = pdstline;
        for (j=0; j<w; j++) {
            //565 b|g|r -> 888 r|g|b
            *pdstdot++ = (unsigned char)(((*psrcdot) >> 0 ) << 3);
            *pdstdot++ = (unsigned char)(((*psrcdot) >> 5 ) << 2);
            *pdstdot++ = (unsigned char)(((*psrcdot) >> 11) << 3);
            psrcdot++;
        }
        psrcline += srclinesize;
        pdstline += dstlinesize;
    }

    return 0;
}

static int rgb888_to_rgb565(const void * psrc, int w, int h, void * pdst)
{
    int srclinesize = UpAlign4(w * 3);
    int dstlinesize = UpAlign4(w * 2);

    const unsigned char * psrcline;
    const unsigned char * psrcdot;
    unsigned char  * pdstline;
    unsigned short * pdstdot;

    int i,j;

    if (!psrc || !pdst || w <= 0 || h <= 0) {
        printf("rgb888_to_rgb565 : parameter error\n");
        return -1;
    }

    psrcline = (const unsigned char *)psrc;
    pdstline = (unsigned char *)pdst;
    for (i=0; i<h; i++) {
        psrcdot = psrcline;
        pdstdot = (unsigned short *)pdstline;
        for (j=0; j<w; j++) {
            //888 r|g|b -> 565 b|g|r
            *pdstdot =  (((psrcdot[0] >> 3) & 0x1F) << 0)//r
                        |(((psrcdot[1] >> 2) & 0x3F) << 5)//g
                        |(((psrcdot[2] >> 3) & 0x1F) << 11);//b
            psrcdot += 3;
            pdstdot++;
        }
        psrcline += srclinesize;
        pdstline += dstlinesize;
    }

    return 0;
}

static int rgb565_to_rgbx8888(const void * psrc, int w, int h, void * pdst)
{
    int srclinesize = UpAlign4(w * 2);
    int dstlinesize = UpAlign4(w * 4);

    const unsigned char  * psrcline;
    const unsigned short * psrcdot;
    unsigned char  * pdstline;
    unsigned char  * pdstdot;

    int i,j;

    if (!psrc || !pdst || w <= 0 || h <= 0) {
        printf("rgb565_to_rgbx8888 : parameter error\n");
        return -1;
    }

    psrcline = (const unsigned char *)psrc;
    pdstline = (unsigned char *)pdst;
    for (i=0; i<h; i++) {
        psrcdot = (const unsigned short *)psrcline;
        pdstdot = pdstline;
        for (j=0; j<w; j++) {
            pdstdot++;
            *pdstdot++ = (unsigned char)(((*psrcdot) >> 0 ) << 3);
            *pdstdot++ = (unsigned char)(((*psrcdot) >> 5 ) << 2);
            *pdstdot++ = (unsigned char)(((*psrcdot) >> 11) << 3);
            psrcdot++;
        }
        psrcline += srclinesize;
        pdstline += dstlinesize;
    }

    return 0;
}

static int rgbx8888_to_rgb565(const void * psrc, int w, int h, void * pdst)
{
    int srclinesize = UpAlign4(w * 4);
    int dstlinesize = UpAlign4(w * 2);

    const unsigned char * psrcline;
    const unsigned char * psrcdot;
    unsigned char  * pdstline;
    unsigned short * pdstdot;

    int i,j;

    if (!psrc || !pdst || w <= 0 || h <= 0) {
        printf("rgbx8888_to_rgb565 : parameter error\n");
        return -1;
    }

    psrcline = (const unsigned char *)psrc;
    pdstline = (unsigned char *)pdst;
    for (i=0; i<h; i++) {
        psrcdot = psrcline;
        pdstdot = (unsigned short *)pdstline;
        for (j=0; j<w; j++) {
            //888 r|g|b -> 565 b|g|r
            *pdstdot =  (((psrcdot[1] >> 3) & 0x1F) << 0)//r
                |(((psrcdot[2] >> 2) & 0x3F) << 5)//g
                |(((psrcdot[3] >> 3) & 0x1F) << 11);//b
            psrcdot += 4;
            pdstdot++;
        }
        psrcline += srclinesize;
        pdstline += dstlinesize;
    }

    return 0;
}

static int rgb888_to_rgbx8888(const void * psrc, int w, int h, void * pdst)
{
    int srclinesize = UpAlign4(w * 3);
    int dstlinesize = UpAlign4(w * 4);

    const unsigned char * psrcline;
    const unsigned char * psrcdot;
    unsigned char  * pdstline;
    unsigned char  * pdstdot;

    int i,j;

    if (!psrc || !pdst || w <= 0 || h <= 0) {
        printf("rgb888_to_rgbx8888 : parameter error\n");
        return -1;
    }

    psrcline = (const unsigned char *)psrc;
    pdstline = (unsigned char *)pdst;
    for (i=0; i<h; i++) {
        psrcdot = psrcline;
        pdstdot = pdstline;
        for (j=0; j<w; j++) {
            *pdstdot++ = 0;
            *pdstdot++ = *psrcdot++;
            *pdstdot++ = *psrcdot++;
            *pdstdot++ = *psrcdot++;
        }
        psrcline += srclinesize;
        pdstline += dstlinesize;
    }

    return 0;
}

static int rgbx8888_to_rgb888(const void * psrc, int w, int h, void * pdst)
{
    int srclinesize = UpAlign4(w * 4);
    int dstlinesize = UpAlign4(w * 3);

    const unsigned char * psrcline;
    const unsigned char * psrcdot;
    unsigned char  * pdstline;
    unsigned char  * pdstdot;

    int i,j;

    if (!psrc || !pdst || w <= 0 || h <= 0) {
        printf("rgbx8888_to_rgb888 : parameter error\n");
        return -1;
    }

    psrcline = (const unsigned char *)psrc;
    pdstline = (unsigned char *)pdst;
    for (i=0; i<h; i++) {
        psrcdot = psrcline;
        pdstdot = pdstline;
        for (j=0; j<w; j++) {
            psrcdot++;
            *pdstdot++ = *psrcdot++;
            *pdstdot++ = *psrcdot++;
            *pdstdot++ = *psrcdot++;
        }
        psrcline += srclinesize;
        pdstline += dstlinesize;
    }

    return 0;
}

void * rgb565_to_rgb888_buffer(const void * psrc, int w, int h)
{
    int size = h * UpAlign4(w * 3);
    void * pdst = NULL;
    if (psrc && w > 0 && h > 0) {
        pdst = malloc(size);
        if (pdst) {
            if (rgb565_to_rgb888(psrc, w, h, pdst)) {
                free(pdst);
                pdst = NULL;
            }
        }
    }
    return pdst;
}

void * rgb888_to_rgb565_buffer(const void * psrc, int w, int h)
{
    int size = h * UpAlign4(w * 2);
    void * pdst = NULL;
    if (psrc && w > 0 && h > 0) {
        pdst = malloc(size);
        if (pdst) {
            if (rgb888_to_rgb565(psrc, w, h, pdst)) {
                free(pdst);
                pdst = NULL;
            }
        }
    }
    return pdst;
}

void * rgb565_to_rgbx8888_buffer(const void * psrc, int w, int h)
{
    int size = h * UpAlign4(w * 4);
    void * pdst = NULL;
    if (psrc && w > 0 && h > 0) {
        pdst = malloc(size);
        if (pdst) {
            if (rgb565_to_rgbx8888(psrc, w, h, pdst)) {
                free(pdst);
                pdst = NULL;
            }
        }
    }
    return pdst;
}

void * rgbx8888_to_rgb565_buffer(const void * psrc, int w, int h)
{
    int size = h * UpAlign4(w * 2);
    void * pdst = NULL;
    if (psrc && w > 0 && h > 0) {
        pdst = malloc(size);
        if (pdst) {
            if (rgbx8888_to_rgb565(psrc, w, h, pdst)) {
                free(pdst);
                pdst = NULL;
            }
        }
    }
    return pdst;
}

void * rgb888_to_rgbx8888_buffer(const void * psrc, int w, int h)
{
    int size = h * UpAlign4(w * 4);
    void * pdst = NULL;
    if (psrc && w > 0 && h > 0) {
        pdst = malloc(size);
        if (pdst) {
            if (rgb888_to_rgbx8888(psrc, w, h, pdst)) {
                free(pdst);
                pdst = NULL;
            }
        }
    }
    return pdst;
}

void * rgbx8888_to_rgb888_buffer(const void * psrc, int w, int h)
{
    int size = h * UpAlign4(w * 3);
    void * pdst = NULL;
    if (psrc && w > 0 && h > 0) {
        pdst = malloc(size);
        if (pdst) {
            if (rgbx8888_to_rgb888(psrc, w, h, pdst)) {
                free(pdst);
                pdst = NULL;
            }
        }
    }
    return pdst;
}

static const RGB_CONVERT_FUN g_convert_func[3][3] =
{
    {NULL, rgb565_to_rgb888_buffer, rgb565_to_rgbx8888_buffer},
    {rgb888_to_rgb565_buffer, NULL, rgb888_to_rgbx8888_buffer},
    {rgbx8888_to_rgb565_buffer, rgbx8888_to_rgb888_buffer, NULL}
};

RGB_CONVERT_FUN get_convert_func(int frombpp, int tobpp)
{
    RGB_CONVERT_FUN func_ptr = NULL;
    frombpp = UpAlign8(frombpp) / 8 - 2;
    tobpp = UpAlign8(tobpp) / 8 - 2;
    if ((frombpp >= 0 && frombpp <= 2)
        && (tobpp >= 0 && tobpp <= 2)) {
        func_ptr = g_convert_func[frombpp][tobpp];
    }
    return func_ptr;
}

//-------------------------------------------------------------------