add jpeg_rescue.c and jpeg_truncate.c and Makefile

emon · Mar 9, 2010 · 439f48a · 439f48a
1 parent abb2cef
commit 439f48a
Show file tree

Hide file tree

Showing 4 changed files with 217 additions and 0 deletions.
diff --git a/Makefile b/Makefile
@@ -0,0 +1,14 @@
+ALLTARGETS=jpeg_rescue jpeg_truncate
+
+all: $(ALLTARGETS)
+
+jpeg_rescue: jpeg_rescue.o
+	$(CC) -o $@ $>
+
+jpeg_truncate: jpeg_truncate.o
+	$(CC) -o $@ $>
+
+
+clean:
+	rm *.o $(ALLTARGETS)
+
diff --git a/README b/README
@@ -0,0 +1,26 @@
+These tools rescue JPEG files from broken SD/USB memory cards 
+
+* jpeg_rescue
+
+'jpeg_rescue' rescues JPEG files from broken SD/USB memory cards.
+This tool expects JPEG files are wrote sequentially in memory device.
+
+This tool searches JPEG Start Of Image (0xff 0xd8) from top of
+each cluster (4KB block) and pick up data (to just before next SOI).
+
+usage: 
+
+1. insert broekn SD/USB memory into slot of your PC.
+2. when your memory device appears in /dev/da0
+ # dd if=/dev/da0 of=hogehoge bs=1m
+ # jpeg_rescue hogehoge
+ or
+ # jpeg_rescue /dev/da0
+
+
+* jpeg_truncate
+'jpeg_truncate' truncates unnecessary end of data
+This tool trancate garbage after JPEG End Of Image (0xff 0xd9)
+
+usage:
+ % jpeg_truncate *.jpg
diff --git a/jpeg_rescue.c b/jpeg_rescue.c
@@ -0,0 +1,86 @@
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#define MAXBUF 4096
+#define BLOCKSIZE 4096
+#define MAXJPEGSIZE (1024*1024*10)
+
+int is_jpeg_startofimage(unsigned char *buf)
+{
+	if(buf[0] == 0xff &&
+	   buf[1] == 0xd8){
+		return 1;
+	} else {
+		return 0;
+	}
+}
+
+
+int main(int argc, char** argv)
+{
+	FILE *ifp;
+	char *ifname;
+
+	FILE *ofp = NULL;
+	char ofname[8+1+3+1];
+	size_t oflen;
+
+	unsigned char buf[MAXBUF];
+	int cl = 0;
+
+	int i = 0;
+
+	if(argc != 2){
+		fprintf(stderr, "please specify filename\n");
+		return -1;
+	}
+	ifname = argv[1];
+
+	if((ifp=fopen(ifname, "r"))==NULL){
+		fprintf(stderr, "can not open file: '%s'\n", ifname);
+		return -1;
+	}
+
+	while(!feof(ifp)){
+		int err;
+
+		cl++;
+		if((err=fread(buf, BLOCKSIZE, 1, ifp))!=1){
+			fprintf(stderr, "fread: error=%d, skip cl=%ld\n", err, cl);
+			continue;
+		}
+		if(oflen > MAXJPEGSIZE){
+			fprintf(stderr, ", cut [%ld]\n", oflen);
+			fclose(ofp);
+			ofp = NULL;
+			oflen = 0;
+		}
+		if(is_jpeg_startofimage(buf)){
+			if(ofp!=NULL){
+				fprintf(stderr, ", done [%ld]\n", oflen);
+				fclose(ofp);
+				ofp = NULL;
+				oflen = 0;
+			}
+			snprintf(ofname, sizeof(ofname), "%08ld.jpg", i++);
+			fprintf(stderr, "writing: %s", ofname);
+			oflen = 0;
+			if((ofp = fopen(ofname, "w"))==NULL){
+				fprintf(stderr, ": faile\n");
+				continue;
+			}
+
+		}
+		if(ofp == NULL){
+			fprintf(stderr, "skip: cl=%d because ofp=NULL\n", cl);
+			continue;
+		}
+		if((err=fwrite(buf, BLOCKSIZE, 1, ofp))!=1){
+			fprintf(stderr, "fwrite: error=%d, skip cl=%ld\n", err, cl);
+			continue;
+		}
+		oflen += BLOCKSIZE;
+	}
+	return 0;
+}
diff --git a/jpeg_truncate.c b/jpeg_truncate.c
@@ -0,0 +1,91 @@
+#include <assert.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#define BUFMAX 4096
+
+long where_jpeg_endofimage(unsigned char *buf, long size)
+{
+	long p;
+	int stage = 0;
+
+	for(p = size-1; p>0l; p--){
+		switch(stage){
+		case 0:
+			if(buf[p] == 0xd9){
+				stage++;
+			}
+			break;
+		case 1:
+			if(buf[p] == 0xff){
+				stage++;
+			} else {
+				stage--;
+			}
+			break;
+		case 2:
+			return p + 3;
+			break;
+		default:
+			fprintf(stderr, "unsupported stage: %d\n", stage);
+			break;
+		}
+	}
+	return 0;
+}
+
+
+size_t getfilesize(int fd)
+{
+	struct stat sb;
+
+	assert(fstat(fd, &sb) >= 0);
+	return sb.st_size;
+}
+
+
+int jpeg_trancate(char *ifname)
+{
+	int ifd;
+	void *ifmap;
+	long ifsize;
+	long offset;
+
+	ifd = open(ifname, O_RDWR);
+	assert(ifd != -1);
+	ifsize = getfilesize(ifd);	/* get file size */
+
+	fprintf(stderr, "open %s [%ld]", ifname, ifsize);
+
+	ifmap = mmap(NULL, ifsize, PROT_READ, MAP_PRIVATE, ifd, 0);
+	assert(ifmap != MAP_FAILED);
+
+	offset = where_jpeg_endofimage(ifmap, ifsize);
+
+	fprintf(stderr, " -> [%ld = 0x%x] (%ld)\n", offset, offset, offset-ifsize);
+
+	ftruncate(ifd, offset);
+	fprintf(stderr, "truncated\n");
+	return offset;
+}
+
+
+int main(int argc, char **argv)
+{
+	int i;
+
+	if(argc < 2){
+		fprintf(stderr, "please specify file name\n");
+		return -1;
+	}
+
+	for(i = 1; i < argc; i++){
+		jpeg_trancate(argv[i]);
+	}
+	return 0;
+}
+