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  1. PO
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    <p>You cannot read less than one byte at a time. However you can use bitmasks and shift operations to set the last two bits to <code>0</code> (if you are storing 16), and carry the two unused bits you removed for the next value. This will probably made the decoding operation a lot more complicated and expensive though.</p> <p>How about decoding the values 8 by 8 (you can read 14 chars = 112 bits = 8 * 14 bits)? I have NOT tested this code, and there are probably some typos in there. It does compile but i don't have your file to test it:</p> <pre><code>#include &lt;stdio.h&gt; int main(){ FILE *file = fopen ("...", "rt"); // loop variable unsigned int i; // temporary buffer char buffer[14]; // your decoded ints int decoded[8]; while(fgets(buffer, 14, file) != NULL) { int cursor = 0; // we do this loop only twice since the offset resets after 4 * 14 for(i = 0; i &lt;= 4; i+= 4){ // first decoded int is 16 bits decoded[i+0] = (buffer[cursor++] | (buffer[cursor++] &lt;&lt; 8)); // second is 2 + 8 + 8 = 18 bits (offset = 2) decoded[i+1] = (decoded[i+0] &gt;&gt; 14) | buffer[cursor++] &lt;&lt; 2 | buffer[cursor++] &lt;&lt; 10; // third is 4 + 8 + 8 = 20 bits (offset = 4) decoded[i+2] = (decoded[i+1] &gt;&gt; 14) | buffer[cursor++] &lt;&lt; 4 | buffer[cursor++] &lt;&lt; 12; // next is 6 + 8 = 14 bits (offset = 6) decoded[i+3] = (decoded[i+2] &gt;&gt; 14) | buffer[cursor++] &lt;&lt; 6; } // trim the numbers to 14 bits for(i = 0; i &lt; 8; ++i) decoded[i] &amp;= ((1 &lt;&lt; 15) - 1); } fclose(file); } </code></pre> <p>Note that I don't do anything with the decoded ints, and I write on the same array over and over again, this is just an illustration. You can factorize the code more but I unrolled the loops and commented the operations so that you see how it works.</p>
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    1. POHow to read a binary file 14 bits at a time instead of 8?
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    1. USThibaut
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    1. COThe question is tagged as C, not C++.
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      1. USAlexey Frunze
    2. COOops, my bad. I removed this solution.
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      1. USThibaut
    3. COThank you Thibaut. I think the original code does what you suggest, in a slightly different way.
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