//////////////////////////////////////////////////bmp.c///////////////////////////////////////////// ///////////////////////////////////*fbv -- simple image viewer for the linuxframebufferCopyright (C) 2002 Tomasz SternaThis program is free software; you can redistribute it and/or modifyit under the terms of the GNU General Public License as published bythe Free Software Foundation; either version 2 of the License, or(at your option) any later version.This program 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 theGNU General Public License for more details.You should have received a copy of the GNU General Public Licensealong with this program; if not, write to the Free SoftwareFoundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.*/#include "config.h"#ifdef FBV_SUPPORT_BMP#include "fbv.h"#include <sys/types.h>#include <sys/stat.h>#include <fcntl.h>#include <unistd.h>#define BMP_TORASTER_OFFSET 10#define BMP_SIZE_OFFSET 18#define BMP_BPP_OFFSET 28#define BMP_RLE_OFFSET 30#define BMP_COLOR_OFFSET54#define fill4B(a) ( ( 4 - ( (a) % 4 ) ) & 0x03)struct color {unsigned char red;unsigned char green;unsigned char blue;};intfh_bmp_id(char *name)//读取位图头信息，判断是否为"BM"intfd;char id[2];fd = open(name, O_RDONLY);//打开文件if (fd == -1) {return(0);}read(fd, id, 2);close(fd);if ( id[0]=='B' && id[1]=='M' ) {return(1);}return(0);}void fetch_pallete(intfd, struct color pallete[], int count)//获取调色板信息{unsigned char buff[4];int i;lseek(fd, BMP_COLOR_OFFSET, SEEK_SET);//fd,28,SEEK_SET:参数28为新的读写位置for (i=0; i<count; i++) {read(fd, buff, 4);//将fd所指向的文件的4个字节传送给缓冲区（指针）buff所指内存中pallete[i].red = buff[2];pallete[i].green = buff[1];pallete[i].blue = buff[0];}return;}intfh_bmp_load(char *name,unsigned char *buffer, unsigned char **alpha, intx,int y){#if 1intfd, bpp, raster, i, j, k, skip;unsigned char buff[4];unsigned char *wr_buffer = buffer + x*(y-1)*3;struct color pallete[256];fd = open(name, O_RDONLY);if (fd == -1) {return(FH_ERROR_FILE);}if (lseek(fd, BMP_TORASTER_OFFSET, SEEK_SET) == -1) {//从文件10处开始读写return(FH_ERROR_FORMAT);}read(fd, buff, 4);raster = buff[0] + (buff[1]<<8) + (buff[2]<<16) + (buff[3]<<24);//由上面可知：从bfOffBits//开始四个字节：每一行扫描的字节数？if (lseek(fd, BMP_BPP_OFFSET, SEEK_SET) == -1) {return(FH_ERROR_FORMAT);}read(fd, buff, 2);bpp = buff[0] + (buff[1]<<8);//可得biBitCount(从28开始2个字节)switch (bpp){case 1: /* monochrome 单色*/skip = fill4B(x/8+(x%8?1:0));/*#define fill4B(a) ( ( 4 - ( (a) % 4 ) ) & 0x03)1.BMP文件记录一行图像是以字节为单位的。
因此，就不存在一个字节中的数据位信息表示的点在不同的两行中。
也就是说，设显示模式位16色，在每个字节分配两个点信息时，如果图像的宽度位奇数，那么最后一个像素点的信息将独占一个字节，这个字节的后4位将没有意义。
接下来的一个字节将开始记录下一行的信息。
2.为了显示的方便，除了真彩色外，其他的每中颜色模式的行字节数要用数据“00”补齐为4的整数倍。
如果显示模式为16色，当图像宽为19时，存储时每行则要补充4-(19/2+1)%4=2个字节（加1是因为里面有一个像素点要独占了一字节）。
如果显示模式为256色，当图像宽为19时，每行也要补充4-19%4=1个字节。
*/lseek(fd, raster, SEEK_SET);for (i=0; i<y; i++) {for (j=0; j<x/8; j++) {read(fd, buff, 1);for (k=0; k<8; k++) {if (buff[0] & 0x80) {*wr_buffer++ = 0xff;*wr_buffer++ = 0xff;*wr_buffer++ = 0xff;} else {*wr_buffer++ = 0x00;*wr_buffer++ = 0x00;*wr_buffer++ = 0x00;}buff[0] = buff[0]<<1;}}if (x%8) {read(fd, buff, 1);for (k=0; k<x%8; k++) {if (buff[0] & 0x80) {*wr_buffer++ = 0xff;*wr_buffer++ = 0xff;*wr_buffer++ = 0xff;} else {*wr_buffer++ = 0x00;*wr_buffer++ = 0x00;*wr_buffer++ = 0x00;}buff[0] = buff[0]<<1;}}if (skip) {read(fd, buff, skip);}wr_buffer -= x*6; /* backoff 2 lines - x*2 *3 */}break;case 4: /* 4bit palletized */skip = fill4B(x/2+x%2);//#define fill4B(a) ( ( 4 - ( (a) % 4 ) ) & 0x03) fetch_pallete(fd, pallete, 16);lseek(fd, raster, SEEK_SET);for (i=0; i<y; i++) {for (j=0; j<x/2; j++) {read(fd, buff, 1);buff[1] = buff[0]>>4;buff[2] = buff[0] & 0x0f;*wr_buffer++ = pallete[buff[1]].red;*wr_buffer++ = pallete[buff[1]].green;*wr_buffer++ = pallete[buff[1]].blue;*wr_buffer++ = pallete[buff[2]].red;*wr_buffer++ = pallete[buff[2]].green;*wr_buffer++ = pallete[buff[2]].blue;}if (x%2) {read(fd, buff, 1);buff[1] = buff[0]>>4;*wr_buffer++ = pallete[buff[1]].red;*wr_buffer++ = pallete[buff[1]].green;*wr_buffer++ = pallete[buff[1]].blue;}if (skip) {read(fd, buff, skip);}wr_buffer -= x*6; /* backoff 2 lines - x*2 *3 */ }break;case 8: /* 8bit palletized */skip = fill4B(x);fetch_pallete(fd, pallete, 256);lseek(fd, raster, SEEK_SET);for (i=0; i<y; i++) {for (j=0; j<x; j++) {read(fd, buff, 1);*wr_buffer++ = pallete[buff[0]].red;*wr_buffer++ = pallete[buff[0]].green;*wr_buffer++ = pallete[buff[0]].blue;}if (skip) {read(fd, buff, skip);}wr_buffer -= x*6; /* backoff 2 lines - x*2 *3 */ }break;case 16: /* 16bit RGB */return(FH_ERROR_FORMAT);break;case 24: /* 24bit RGB */skip = fill4B(x*3);lseek(fd, raster, SEEK_SET);for (i=0; i<y; i++) {for (j=0; j<x; j++) {read(fd, buff, 3);*wr_buffer++ = buff[2];*wr_buffer++ = buff[1];*wr_buffer++ = buff[0];}if (skip) {read(fd, buff, skip);}wr_buffer -= x*6; /* backoff 2 lines - x*2 *3 */}break;default:return(FH_ERROR_FORMAT);}close(fd);return(FH_ERROR_OK);#endif}intfh_bmp_getsize(char *name,int *x,int *y){intfd;unsigned char size[4];fd = open(name, O_RDONLY);if (fd == -1) {return(FH_ERROR_FILE);//宏定义FH_ERROR_FILE 1; 见fbv.h}if (lseek(fd, BMP_SIZE_OFFSET, SEEK_SET) == -1) {//BMP_SIZE_OFFSET :28return(FH_ERROR_FORMAT);//FH_ERROR_FORMAT:2}read(fd, size, 4);*x = size[0] + (size[1]<<8) + (size[2]<<16) + (size[3]<<24);// *x-=1;read(fd, size, 4);*y = size[0] + (size[1]<<8) + (size[2]<<16) + (size[3]<<24);close(fd);return(FH_ERROR_OK);}#endif//////////////////////////////////////////////////bmp.c///////////////////////////////////////////// ////////////////////////////////////////////////////////////////////////////////////main.c///////////////////////////////////////////// //////////////////////////////////#include <stdio.h>#include <sys/time.h>#include <sys/types.h>#include <unistd.h>#include <getopt.h>#include <termios.h>#include <string.h>#include <signal.h>#include <stdio.h>#include <stdlib.h>#include <fcntl.h>#include <asm/mman.h>#include <linux/fb.h>#include <pthread.h>#include <semaphore.h>#include <errno.h>#include <dirent.h>#include <linux/input.h>#include <linux/rtc.h>#include "config.h"#include "fbv.h"#include <sys/syscall.h>#include <unistd.h>#if 1#define UI_w 240#define UI_h 320/////////unsigned char *fbdis = 0;///////////staticintopt_clear = 1,opt_alpha = 0,opt_hide_cursor = 1,opt_image_info = 1,opt_stretch = 0,opt_delay = 0,opt_enlarge = 0,opt_ignore_aspect = 0;intcmp;voiddisplay_rgb( unsigned char * dis_data,intW,int H){staticintfbfd = 0;staticintkh=0;inttfd=0;structfb_var_screeninfovinfo;structfb_fix_screeninfofinfo;int blank=0;longintscreensize = 0;unsigned char * buf;int x = 0, y = 0,z=0;// Open the file for reading and writingfbfd = open("/dev/fb0", O_RDWR);//打开显示设备if (fbfd< 0) {printf("Error: cannot open framebuffer device.\n");exit(1);}// Get fixed screen informationif (ioctl(fbfd, FBIOGET_FSCREENINFO, &finfo)) {//printf("Error reading fixed information.\n");exit(2);}// Get variable screen informationif (ioctl(fbfd, FBIOGET_VSCREENINFO, &vinfo)) {//获取屏的显示信息printf("Error reading variable information.\n");exit(3);}printf("%dx%d, %dbpp\n", vinfo.xres, vinfo.yres, vinfo.bits_per_pixel );//vinfo.bits_per_pixel:每个像素//所占比特，也就是biBitCount// Figure out the size of the screen in bytes:计算出屏幕大小，单位bit screensize = vinfo.xres * vinfo.yres * vinfo.bits_per_pixel / 8;// Map the device to memory：映射设备到内存/*void *mmap(void *start, size_t length, intprot, int flags, intfd, off_toffsize);mmap（）建立内存映射:将某个文件内容映射到内存中，对该内存区域的存取即是对该文件内容的读写。
