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    <p>A very simple approach is to write one bit at a time with something like the following:</p> <pre><code>unsigned char acc; // Accumulator of bit waiting to be written int bitcount; // How many bits are aready present in the accumulator // write a single bit (0/1) void writebit(int bit) { acc |= (bit &lt;&lt; bitcount); if (++bitcount == 8) { writebyte(acc); acc = 0; bitcount = 0; } } </code></pre> <p>to read back a sigle bit the procedure is symmetrical</p> <pre><code>unsigned char acc; // bits waiting to be extracted int bitcount; // how many bits are still available in acc int readbit() { if (bitcount == 0) { bitcount = 8; acc = readbyte(); } --bitcount; return (acc &gt;&gt; (7 - bitcount)) &amp; 1; } </code></pre> <p>of course this is just the simplest approach, but I'd wait before worrying about code speed until you are first able to save and load correctly your encoded data.</p> <h2>Example:</h2> <p>Suppose you have the following Huffman coded symbols</p> <pre><code>A - 0 B - 10 C - 110 D - 111 </code></pre> <p>and that you want to encode the sequence</p> <pre><code>A B A A C D A D B B </code></pre> <p>then you would call in order</p> <pre><code>writebit(0); // A writebit(1); writebit(0); // B writebit(0); // A writebit(0); // A writebit(1); writebit(1); writebit(0); // C writebit(1); writebit(1); writebit(1); // D writebit(0); // A writebit(1); writebit(0); // B writebit(1); writebit(0); // B </code></pre> <p>The actual bytes written would therefore be</p> <pre><code>(01100010) = 0x62 (01010111) = 0x57 </code></pre> <p>(Note that the code shown starts from the least significant bit, i.e. you should read the bit sequences inside the parenthesis from right to left if you want to recognize the symbols).</p>
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    1. POproblem in saving Huffman Code?
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    1. COI want to save Huffman codes into a file. How can I do this? I am saving Huffman codes into a string but size of generated file is bigger than Original file. If file compressed correctly , How can read for extract? i mean if char 'a' has "11" Huffman code and b has "011" Huffman code(both of two has same ASCII code) How can we Understand which One is true 'a' or 'b'?
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    2. COI've added an example of what bytes would be output for a small sequence of Huffman encoded symbols. When reading a bit-coded stream you don't think in terms of bytes, but of bits... a single symbol can happen to be part in one byte and part in another (this however doesn't happen in my example).
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