--- /dev/null
+/* bmp.c -- bmp write/read api
+ *
+ * author: hackbard@hackdaworld.dyndns.org
+ *
+ */
+
+#include "bmp.h"
+
+int bmp_init(t_bmp *bmp,int outfd) {
+
+ dprintf(outfd,"[bmp] initializing bmp api ...\n");
+
+ memset(bmp,0,sizeof(t_bmp));
+ bmp->outfd=outfd;
+
+ return B_SUCCESS;
+}
+
+int bmp_shutdown(t_bmp *bmp) {
+
+ if(bmp->map!=NULL) {
+ dprintf(bmp->outfd,"[bmp] free pixmap memory\n");
+ free(bmp->map);
+ }
+
+ dprintf(bmp->outfd,"[bmp] shutdown\n");
+
+ return B_SUCCESS;
+}
+
+int bmp_check_header_and_info(t_bmp *bmp) {
+
+ if(bmp->info.compression!=0) {
+ dprintf(bmp->outfd,"[bmp] compression not supported\n");
+ return B_NO_SUPPORT;
+ }
+
+ if(bmp->info.bpp!=24) {
+ dprintf(bmp->outfd,"[bmp] only true color (24bpp) supported\n");
+ return B_NO_SUPPORT;
+ }
+
+ if(bmp->hdr.offset!=B_H_SIZE+B_I_SIZE) {
+ dprintf(bmp->outfd,"[bmp] files with %d bytes offset not supported\n",
+ bmp->hdr-offset);
+ return B_NO_SUPPORT;
+ }
+
+ if(bmp->info.size!=BMP_I_SIZE) {
+ dprintf(bmp->outfd,"[bmp] files with %d bytes info size not supported\n",
+ bmp->info.size);
+ return B_NO_SUPPORT;
+ }
+
+ return B_SUCCESS;
+}
+
+int bmp_write_file(t_bmp *bmp) {
+
+ int fill,xsize,size;
+
+ xsize=bmp->width*3;
+ fill=(4-(xsize%4))%4;
+ size=(xsize+fill)*bmp->height;
+
+ /* construct it */
+ bmp->hdr.identifier='B'|('M'<<8);
+ bmp->hdr.size=size+BMP_H_SIZE+BMP_I_SIZE;
+ bmp->hdr.offset=BMP_H_SIZE+BMP_I_SIZE;
+ bmp->info.size=BMP_I_SIZE;
+ bmp->info.width=bmp->width;
+ bmp->info.height=bmp->height;
+ bmp->info.planes=1;
+ bmp->info.bpp=24;
+ bmp->info.imagesize=size;
+ if(bmp->info.xres==0) bmp->info.xres=2048;
+ if(bmp->info.yres==0) bmp->info.yres=2048;
+ bmp->info.noc=0;
+ bmp->info.ic=0;
+
+ /* write it */
+ ...
+
+
+ return B_SUCCESS;
+}
+
+int bmp_read_file(t_bmp *bmp) {
+
+ unsigned char buf[BMP_HI_SIZE];
+ int y,xsize;
+ int crop;
+ unsigned char *data;
+
+ if(!(bmp->mode&READ)) {
+ dprintf(bmp->outfd,"[bmp] read mode not specified");
+ return B_NO_READ_MODE;
+ }
+
+ if((bmp->fd=open(bmp->file,O_RDONLY))<0) {
+ dprintf(bmp->outfd,"[bmp] unable to open file %s\n",bmp->file);
+ return B_NO_FILE;
+ }
+
+ if(read(bmp->fd,buf,BMP_H_SIZE+BMP_I_SIZE)<BMP_H_SIZE+BMP_I_SIZE) {
+ dprintf(bmp->outfd,"[bmp] error reading bmp header & info\n");
+ return B_NO_HI;
+ }
+
+ memcpy(&(bmp->hdr),buf,BMP_H_SIZE);
+ memcpy(&(bmp->info),buf+BMP_H_SIZE,BMP_I_SIZE);
+
+ if(bmp_check_header_and_info(bmp)!=B_SUCCESS) {
+ dprintf(bmp->outfd,"[bmp] header/info check failed\n");
+ return B_HI_FAIL;
+ }
+
+ bmp->map=(t_pixel *)malloc(bmp->info.width*bmp->info.height*sizeof(t_pixel));
+ if(bmp->map==NULL) {
+ dprintf(bmp->outfd,"[bmp] malloc of map memory failed\n");
+ return B_E_MEM;
+ }
+
+ crop=(bmp->info.imagesize/bmp->info.height)%4;
+ xsize=(bmp->info.bpp/8)*bmp->info.width;
+
+ for(y=0;y<bmp->info.height;y++) {
+ if(read(bmp->fd,bmp->map+y*bmp->info.width,xsize)<xsize) {
+ dprintf(bmp->outfd,"[bmp] reading image data of line %d failed\n",y);
+ return B_E_READ_DATA;
+ }
+ if(read(bmp->fd,buf,crop)<crop) {
+ dprintf(bmp->outfd,"[bmp] failed reading rest of line\n");
+ return B_E_READ_DATA;
+ }
+ }
+
+ close(bmp->fd);
+
+ return B_SUCCESS;
+}
--- /dev/null
+/* bmp.h -- bmp headers */
+
+#ifndef BMP_H
+#define BMP_H
+
+/* includes */
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+
+/* defines */
+#define B_SUCCESS 1
+#define B_ERROR -1
+#define B_NO_READ_MODE -2
+#define B_NO_FILE -3
+#define B_NO_HI -4
+#define B_NO_SUPPORT -5
+#define B_HI_FAIL -6
+#define B_E_MEM -7
+#define B_E_READ_DATA -8;
+#define MAX_CHARS_FILE 32
+#define BMP_H_SIZE 14
+#define BMP_I_SIZE 40
+
+/* bmp specific variables */
+typedef struct s_bmp_hdr {
+ unsigned short int identifier;
+ unsigned int size;
+ unsigned short int reserved1;
+ unsigned short int reserved2;
+ unsigned int offset; /* <- 14 + 40 bytes = 0x36 */
+} t_bmp_hdr; /* 14 bytes */
+
+typedef struct s_bmp_info {
+ unsigned int size; /* 40 bytes = 0x28 */
+ int width;
+ int height;
+ unsigned short int planes;
+ unsigned short int bpp;
+ unsigned int compression;
+ unsigned int imagesize;
+ unsigned int xres;
+ unsigned int yres;
+ unsigned int noc;
+ unsigned int ic;
+} t_bmp_info; /* 40 bytes */
+
+typedef struct s_pixel {
+ unsigned char r;
+ unsigned char g;
+ unsigned char b;
+} t_pixel;
+
+typedef struct s_bmp {
+ int outfd;
+ int width;
+ int height;
+ unsigned char mode;
+#define READ (1<<0)
+#define WRITE (1<<1)
+ char file[MAX_CHARS_FILE];
+ int fd;
+ t_bmp_hdr hdr;
+ t_bmp_info info;
+ t_pixel *map;
+} t_bmp;
+
+/* function prototypes */
+int bmp_init(t_bmp *bmp);
+int bmp_shutdown(t_bmp *bmp);
+
+#endif
size=1;
for(i=0;i<fourier->dim;i++) size*=fourier->data_len[i];
+ dprintf(fourier->outfd,"[fourier] allocating %d bytes for data ...\n",
+ 2*size*sizeof(t_complex));
+
fourier->data=(t_complex *)malloc(2*size*sizeof(t_complex));
fourier->ftdata=&(fourier->data[size]);
return F_SUCCESS;
}
+/* fft functions */
+
+int fourier_fft_1d_init(t_fourier *fourier) {
+
+ unsigned int i,j,m,r;
+ int mask[32];
+
+ /* calculate m = log 2 (N) + check N = 2^m */
+ m=0;
+ while(m<32) {
+ if(1<<m==fourier->data_len[0]) break;
+ else m++;
+ }
+ if(m==32) {
+ dprintf(fourier->outfd,
+ "[fourier] fft impossible (N > 2^32 or not a power of 2\n");
+ return F_FFT_IMPOSSIBLE;
+ }
+ dprintf(fourier->outfd,"[fourier] log2(%d) = %d\n",fourier->data_len[0],m);
+ fourier->log2len[0]=m;
+
+ /* pointer array which will point to reversed t_complex data */
+ fourier->revdata=(t_complex **)malloc(fourier->data_len[0]*sizeof(t_complex *));
+ if(fourier->revdata==NULL) {
+ dprintf(fourier->outfd,
+ "[fourier] malloc for reversed data pointers failed\n");
+ return F_ALLOC_FAIL;
+ }
+
+ dprintf(fourier->outfd,"[fourier] fft: allocated data pointers\n");
+
+ /* swap data (bit reversal) */
+ for(i=0;i<m;i++) mask[i]=1<<i;
+ for(i=0;i<fourier->data_len[0];i++) {
+ r=0;
+ for(j=0;j<m;j++) r+=(((i&mask[j])>>j)<<(m-j-1));
+ fourier->revdata[i]=fourier->ftdata+r;
+ }
+
+ return F_SUCCESS;
+}
+
+int fourier_fft_1d_shutdown(t_fourier *fourier) {
+
+ dprintf(fourier->outfd,"[fourier] fft shutdown\n");
+
+ free(fourier->revdata);
+
+ return F_SUCCESS;
+}
+
+
int fourier_fft_1d(t_fourier *fourier) {
- int i,j,k;
+ int i,j;
+
+ /* copy src to destination, destination is modified in place */
+ memcpy(fourier->ftdata,fourier->data,fourier->data_len[0]*sizeof(t_complex));
+ /* from now on access bit reversed data by revdata[i]->... */
+
+ // for(i=0;i<fourier->log2len[0];i++) {
-
+
+ // }
+
+
+ for(i=0;i<fourier->data_len[0];i++)
+ dprintf(fourier->outfd,"%f %f\n",
+ fourier->ftdata[i]->r,fourier->revdata[i]->i);
+
+ return F_NOT_SUPPORTED;
return F_SUCCESS;
}
}
int fourier_dft_2d(t_fourier *fourier) {
- return F_NOT_SUPPORTED;
+
+ int off_f,off_r;
+ int u,v,x,y;
+ int X,Y;
+ double arg;
+
+ X=fourier->data_len[0];
+ Y=fourier->data_len[1];
+
+ if(fourier->type&BWD) return F_NOT_SUPPORTED;
+
+ /* stupid way - actually you would do: ft_on_index_1(ft_on_index_2(f(x,y))) */
+ for(v=0;v<Y;v++) {
+ off=v*X;
+ for(u=0;u<X;u++) {
+ fourier->ftdata[off+u].r=0;
+ fourier->ftdata[off+u].i=0;
+ for(y=0;y<Y;y++) {
+ off_r=y*X;
+ for(x=0;x<X;x++) {
+ arg=-2.0*M_PI*((1.0*u*x)/X+(1.0*v*y)/Y);
+ fourier->ftdata[off+u].r+=(cos(arg)*fourier->data[off_r+x].r-sin(arg)*fourier->data[off_r+x].i);
+ fourier->ftdata[off+u].i+=(sin(arg)*fourier->data[off_r+x].r+cos(arg)*fourier->data[off_r+x].i);
+ }
+ }
+ fourier->ftdata[off_f+u].r/=(X*Y);
+ fourier->ftdata[off_f+u].i/=(X*Y);
+ }
+ }
+
+ return F_SUCCESS;
}
int fourier_dft_3d(t_fourier *fourier) {
#define F_NOT_SUPPORTED -2
#define F_DIM_FAILURE -3
#define F_ALLOC_FAIL -4
+#define F_FFT_IMPOSSIBLE -5
/* fourier specific variables */
typedef struct s_complex {
int dim;
t_complex *data;
t_complex *ftdata;
+ t_complex **revdata;
int data_len[MAX_DIM];
+ int log2len[MAX_DIM];
} t_fourier;
/* function prototypes */
int fourier_dft_1d(t_fourier *fourier);
int fourier_dft_2d(t_fourier *fourier);
int fourier_dft_3d(t_fourier *fourier);
+int fourier_fft_1d_init(t_fourier *fourier);
+int fourier_fft_1d(t_fourier *fourier);
+int fourier_shutdown(t_fourier *fourier);
#endif