LPC2478移植TJpgDec成功，分享用户自定义接口函数
#include "lpc24xx_types.h"#include "ff.h"
#include "tjpgd.h"
#include "LCDConf.h"
// 以下3句宏定义在tjpgd.h中修改
#define JD_SZBUF 2048/* Size of stream input buffer (should be multiple of 512) */
#define JD_FORMAT 1 /* Output RGB format 0:RGB888 (3 BYTE/pix), 1:RGB565 (1 WORD/pix) */
#define JD_USE_SCALE 1 /* Use descaling feature for output */
#define DISP_XS 800
#define DISP_YS 600
static int MaskL = 0;
static int MaskR = DISP_XS - 1;
static int MaskT = 0;
static int MaskB = DISP_YS - 1;
u16 Covert_RGB565_to_BGR565(unsigned short inRGB)
{
u16 outBGR = 0;
u16 r,g,b;
b = (inRGB ) & 0x1F;
g = (inRGB>> 5) & 0x3F;
r = (inRGB>>11) & 0x1F;
outBGR = (b << 11) | (g << 5) | r;
return outBGR;
}
// 在屏幕上显示图片
// 屏幕的起始地址在LCD_UPBASE中保存
void lpc24xx_disp_blt (
int left, /* Left end (-32768 to 32767) */
int right, /* Right end (-32768 to 32767, >=left) */
int top, /* Top end (-32768 to 32767) */
int bottom, /* Bottom end (-32768 to 32767, >=right) */
const uint16_t *pat /* Pattern data */
)
{
int yc, xc, xl, xs;
uint16_t pd;
uint16_t *pScrBuf;
uint16_t i;
if (left > right || top > bottom)
{
return; /* Check varidity */
}
if (left > MaskR || right < MaskL|| top > MaskB || bottom < MaskT)
{
return; /* Check if in active area */
}
yc = bottom - top+ 1; /* Vertical size */
xc = right- left + 1;
xs = 0; /* Horizontal size and skip */
if (top < MaskT) /* Clip top of source image if it is out of active area */
{
pat+= xc * (MaskT - top);
yc -= MaskT - top;
top = MaskT;
}
if (bottom > MaskB) /* Clip bottom of source image if it is out of active area */
{
yc -= bottom - MaskB;
bottom = MaskB;
}
if (left < MaskL) /* Clip left of source image if it is out of active area */
{
pat += MaskL - left;
xc -= MaskL - left;
xs += MaskL - left;
left = MaskL;
}
if (right > MaskR) /* Clip right of source image it is out of active area */
{
xc -= right - MaskR;
xs += right - MaskR;
right = MaskR;
}
// 已经计算出了要绘制的x方向pixels和y方向pixels
// 上下左右的值已经校正为，为屏幕上的绝对位置，由此可以算出屏幕缓冲区的起始位置
i = 0;
do /* Send image data */
{
pScrBuf = (uint16_t *)(LCD_UPBASE) + (top+i)*DISP_XS + left;
i++;
xl = xc; // x方向的pixels
do
{
pd = *pat++;
*pScrBuf = Covert_RGB565_to_BGR565(pd);
pScrBuf ++;
} while (--xl);
pat += xs;
} while (--yc);
}
/*-----------------------------------*/
/* JPEG file loader */
/* User defined call-back function to input JPEG data */
UINT lpc24xx_tjd_input (
JDEC* jd, /* Decoder object */
BYTE* buff, /* Pointer to the read buffer (NULL:skip) */
UINT nd /* Number of bytes to read/skip from input stream */
)
{
UINT rb;
FIL *fil = (FIL*)jd->device; /* Input stream of this session */
if (buff) /* Read nd bytes from the input strem */
{
f_read(fil, buff, nd, &rb);
return rb; /* Returns number of bytes could be read */
}
else
{
return (f_lseek(fil, f_tell(fil) + nd) == FR_OK) ? nd : 0;/* Skip nd bytes on the input stream */
}
}
/* User defined call-back function to output RGB bitmap */
UINT lpc24xx_tjd_output (
JDEC* jd, /* Decoder object */
void* bitmap, /* Bitmap data to be output */
JRECT* rect /* Rectangular region to output */
)
{
jd = jd; /* Suppress warning (device identifier is not needed) */
// 特定的情况下返回0，停止解码，自行定义
// if (!rect->left) /* Check user interrupt at left end */
// {
// return 0; /* Abort decompression */
// }
// /* Put the rectangular into the display */
lpc24xx_disp_blt(rect->left, rect->right, rect->top, rect->bottom, (uint16_t*)bitmap);
return 1; /* Continue decompression */
}
// 绘制Jpeg
u32 Commander_DRAWJPEG(char *pPara)
{
FIL fJpeg;
FRESULT FatFsRet;
JDEC jd; /* Decoder object (124 bytes) */
JRESULT rc;
BYTE scale;
BYTE Buff __attribute__ ((aligned(4)));
FatFs_Addons_MountDisk(_T("2:"));
FatFsRet = f_open(&fJpeg,_T("2:/Test.jpg"),FA_READ);
if(FatFsRet != FR_OK)
{
printf("打开 图片 失败!\n");
f_close(&fJpeg);
return FatFsRet;
}
rc = jd_prepare(&jd, lpc24xx_tjd_input, Buff, sizeof(Buff), &fJpeg);
if (rc == JDR_OK)
{
for (scale = 0; scale < 3; scale++) //确定比例因子
{
if ((jd.width >> scale) <= 800 && (jd.height >> scale) <= 600)
{
break;
}
}
rc = jd_decomp(&jd, lpc24xx_tjd_output, scale); //开始解压JPEG文件
}
else
{
printf("图片解码失败!\n");
f_close(&fJpeg);
return FatFsRet;
}
f_close(&fJpeg);
return 0;
} mark 正在找一个JPG编解码的程序。谢谢楼主 楼主这个不错，学习了 lz有没有移植教程啊？我移植后出现这样的警告。。
..\tjpgd.c(488): warning:#188-D: enumerated type mixed with another type
..\tjpgd.c: if (b < 0) return 0 - b; /* Err: invalid code or input */
..\tjpgd.c: ^
..\tjpgd.c(492): warning:#188-D: enumerated type mixed with another type
..\tjpgd.c: if (e < 0) return 0 - e; /* Err: input */
..\tjpgd.c: ^
..\tjpgd.c(510): warning:#188-D: enumerated type mixed with another type
..\tjpgd.c: if (b < 0) return 0 - b; /* Err: invalid code or input error */
..\tjpgd.c: ^
..\tjpgd.c(518): warning:#188-D: enumerated type mixed with another type
..\tjpgd.c: if (d < 0) return 0 - d; /* Err: input device */
..\tjpgd.c: ^
..\tjpgd.c(831): warning:#188-D: enumerated type mixed with another type
..\tjpgd.c: rc = create_huffman_tbl(jd, seg, len);
..\tjpgd.c: ^
..\tjpgd.c(841): warning:#188-D: enumerated type mixed with another type
..\tjpgd.c: rc = create_qt_tbl(jd, seg, len);
..\tjpgd.c: ^
..\tjpgd.c: ..\tjpgd.c: 6 warnings, 0 errors
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