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This is a common error. The last file doesn't match because it's 512 bytes too large. The code checks for EOF, then it reads in another 512 bytes, processes it and checks again for EOF. The problem …

Let's look at some of the code: while (fread(temp, sizeof(unsigned char), 1, file) != 0) { // Read 512 bytes from the inputted file to the temporary array fread(temp, 1, 512, file); // If …

Your code is recovering every other jpeg file because of a logic/structure issue. You have set up your code to do this: read blocks until it finds a jpeg signature write the signature block to a new …

The inner test isn't valid. The line while (buffer[0] != jpg_sig1[0] && buffer[1] != jpg_sig1[1] && buffer[2] != jpg_sig1[2] && (buffer[3] != jpg_sig1[3] || …

Let's assume that the missing } is a cut and paste typo and move on. ;-) The problem is that you have TWO fread() calls. You are failing to process every other 512 byte block of code because it is re …

Look at your file open: FILE* outptr = fopen("title","a"); You are literally naming every file "title". If you do an ls -al you will probably see it in the listing. Maybe you should remove …

There are a number of issues. The code is reading 4*1 bytes at a time, not 1, and not 512. This won't work because an actual signature must appear on a 512 byte boundary. It is possible that by chanc …

To answer your comments, you're starting to catch on. First, reading or writing to/from outside storage (We'll call that r/w from now on, unless specifying one or the other) is always slower than r/w …

It recovers the files, but they are 512 bytes too long. There are two issues with your code. First, the logic flow is flawed. Once the first output file is opened, the code reads in a 512 byte block …

The last comparison is a two part sequence. The first part is what is called a mask and the second part is the comparison. (array[3] & 0xf0) == 0xe0 Remember that this check of the 4th byte o …

Let's look at the following and see what it does: while(fread(buffer, 512,1,inptr) == 1){ // new jpeg if(buffer[0] == 0xff && buffer[1] == 0xd8 && buffer[2] == 0xff && (buf …

Sometimes the simple fix is best. Try initializing the file pointer - always a good idea anyways: FILE* jpegptr = NULL; While it may be that the code will work (I'd have to test it to see), th …

How about an explanation instead. Image files are not just 512 bytes long. They can be any size. The assignment is saying this. You need to read in blocks of data that are 512 bytes long and check …

One major fix is to change this line: img = fopen(image, "w"); It's opening the input file for write! That will erase the current contents of the input file and just cause all kinds of pro …

There are a couple of issues in the code. First, it opens the output files in "a" or append mode. By doing this, if you've run the program before and the files already exist, it will just add more da …