我需要从存储卡中恢复jpeg文件(原始数据)。我已经完成了下面的代码,但是我遇到了段错误,无法识别源。总结一下,我完成了一个循环,以读取512bytes块并查找特定的jpeg标头。如果它是第一个jpeg,则programa将打开一个文件并继续对其进行写入。如果jpeg不是第一张,则关闭上一张图像并继续对其进行写入。
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
int main(int argc, char *argv[])
{
// Check usage
if (argc != 2)
{
printf("Usage: ./recover image\n");
return 1;
}
// Open file
FILE *file = fopen(argv[1], "r");
if (!file)
{
fprintf(stderr, "Could not open %s.\n", argv[1]);
return 1;
}
// open array to store the chunks with enough memory
unsigned char buffer [512];
// variables jpeg count
int img_count = 0;
// open filename img to write to
char filename[8];
FILE *img = NULL;
// create loop to read 512 chunks
while (fread(buffer, 512, 1, file) > 0)
{
if (buffer[0] == 0xff && buffer[1] == 0xd8 && buffer[2] == 0xff && (buffer[3] & 0xf0) == 0xe0)
{
// if theres already a jpeg open
if (img_count > 0)
{
fclose(img);
sprintf(filename, "%i03.jpg", img_count);
img = fopen(filename, "w");
img_count++;
} // first jpeg img count == 0
else if (img_count == 0)
{
sprintf(filename, "%i03.jpg", img_count);
img = fopen(filename, "w");
img_count++;
}
}
//if this is not a new jpeg header, just write to img
if (img_count > 0)
{
fwrite(buffer, 512, 1, img);
}
else
{
continue;
}
}
fclose(img);
fclose(file);
return 0;
}
发现它...错别字,我用的是“%i03.jpg”而不是%03i.jpg“