<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Source of the Rust file `/home/sangenya/.cargo/registry/src/github.com-1ecc6299db9ec823/jpeg-decoder-0.1.22/src/huffman.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>huffman.rs - source</title><link rel="stylesheet" type="text/css" href="../../normalize.css"><link rel="stylesheet" type="text/css" href="../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" type="text/css" href="../../light.css" id="themeStyle"><link rel="stylesheet" type="text/css" href="../../dark.css" disabled ><link rel="stylesheet" type="text/css" href="../../ayu.css" disabled ><script id="default-settings"></script><script src="../../storage.js"></script><script src="../../crates.js"></script><noscript><link rel="stylesheet" href="../../noscript.css"></noscript><link rel="icon" type="image/svg+xml" href="../../favicon.svg">
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</pre><pre class="rust">
<span class="kw">use</span> <span class="kw">crate</span><span class="ident">::read_u8</span>;
<span class="kw">use</span> <span class="ident">error</span>::{<span class="ident">Error</span>, <span class="prelude-ty">Result</span>};
<span class="kw">use</span> <span class="ident">marker::Marker</span>;
<span class="kw">use</span> <span class="ident">parser::ScanInfo</span>;
<span class="kw">use</span> <span class="ident">std::io::Read</span>;
<span class="kw">const</span> <span class="ident">LUT_BITS</span>: <span class="ident">u8</span> <span class="op">=</span> <span class="number">8</span>;
<span class="attribute">#[<span class="ident">derive</span>(<span class="ident">Debug</span>)]</span>
<span class="kw">pub</span> <span class="kw">struct</span> <span class="ident">HuffmanDecoder</span> {
<span class="ident">bits</span>: <span class="ident">u64</span>,
<span class="ident">num_bits</span>: <span class="ident">u8</span>,
<span class="ident">marker</span>: <span class="prelude-ty">Option</span><span class="op"><</span><span class="ident">Marker</span><span class="op">></span>,
}
<span class="kw">impl</span> <span class="ident">HuffmanDecoder</span> {
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">new</span>() <span class="op">-</span><span class="op">></span> <span class="ident">HuffmanDecoder</span> {
<span class="ident">HuffmanDecoder</span> {
<span class="ident">bits</span>: <span class="number">0</span>,
<span class="ident">num_bits</span>: <span class="number">0</span>,
<span class="ident">marker</span>: <span class="prelude-val">None</span>,
}
}
<span class="comment">// Section F.2.2.3</span>
<span class="comment">// Figure F.16</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">decode</span><span class="op"><</span><span class="ident">R</span>: <span class="ident">Read</span><span class="op">></span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>, <span class="ident">reader</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">R</span>, <span class="ident">table</span>: <span class="kw-2">&</span><span class="ident">HuffmanTable</span>) <span class="op">-</span><span class="op">></span> <span class="prelude-ty">Result</span><span class="op"><</span><span class="ident">u8</span><span class="op">></span> {
<span class="kw">if</span> <span class="self">self</span>.<span class="ident">num_bits</span> <span class="op"><</span> <span class="number">16</span> {
<span class="self">self</span>.<span class="ident">read_bits</span>(<span class="ident">reader</span>)<span class="question-mark">?</span>;
}
<span class="kw">let</span> (<span class="ident">value</span>, <span class="ident">size</span>) <span class="op">=</span> <span class="ident">table</span>.<span class="ident">lut</span>[<span class="self">self</span>.<span class="ident">peek_bits</span>(<span class="ident">LUT_BITS</span>) <span class="kw">as</span> <span class="ident">usize</span>];
<span class="kw">if</span> <span class="ident">size</span> <span class="op">></span> <span class="number">0</span> {
<span class="self">self</span>.<span class="ident">consume_bits</span>(<span class="ident">size</span>);
<span class="prelude-val">Ok</span>(<span class="ident">value</span>)
}
<span class="kw">else</span> {
<span class="kw">let</span> <span class="ident">bits</span> <span class="op">=</span> <span class="self">self</span>.<span class="ident">peek_bits</span>(<span class="number">16</span>);
<span class="kw">for</span> <span class="ident">i</span> <span class="kw">in</span> <span class="ident">LUT_BITS</span> .. <span class="number">16</span> {
<span class="kw">let</span> <span class="ident">code</span> <span class="op">=</span> (<span class="ident">bits</span> <span class="op">></span><span class="op">></span> (<span class="number">15</span> <span class="op">-</span> <span class="ident">i</span>)) <span class="kw">as</span> <span class="ident">i32</span>;
<span class="kw">if</span> <span class="ident">code</span> <span class="op"><</span><span class="op">=</span> <span class="ident">table</span>.<span class="ident">maxcode</span>[<span class="ident">i</span> <span class="kw">as</span> <span class="ident">usize</span>] {
<span class="self">self</span>.<span class="ident">consume_bits</span>(<span class="ident">i</span> <span class="op">+</span> <span class="number">1</span>);
<span class="kw">let</span> <span class="ident">index</span> <span class="op">=</span> (<span class="ident">code</span> <span class="op">+</span> <span class="ident">table</span>.<span class="ident">delta</span>[<span class="ident">i</span> <span class="kw">as</span> <span class="ident">usize</span>]) <span class="kw">as</span> <span class="ident">usize</span>;
<span class="kw">return</span> <span class="prelude-val">Ok</span>(<span class="ident">table</span>.<span class="ident">values</span>[<span class="ident">index</span>]);
}
}
<span class="prelude-val">Err</span>(<span class="ident">Error::Format</span>(<span class="string">"failed to decode huffman code"</span>.<span class="ident">to_owned</span>()))
}
}
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">decode_fast_ac</span><span class="op"><</span><span class="ident">R</span>: <span class="ident">Read</span><span class="op">></span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>, <span class="ident">reader</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">R</span>, <span class="ident">table</span>: <span class="kw-2">&</span><span class="ident">HuffmanTable</span>) <span class="op">-</span><span class="op">></span> <span class="prelude-ty">Result</span><span class="op"><</span><span class="prelude-ty">Option</span><span class="op"><</span>(<span class="ident">i16</span>, <span class="ident">u8</span>)<span class="op">></span><span class="op">></span> {
<span class="kw">if</span> <span class="kw">let</span> <span class="prelude-val">Some</span>(<span class="kw-2">ref</span> <span class="ident">ac_lut</span>) <span class="op">=</span> <span class="ident">table</span>.<span class="ident">ac_lut</span> {
<span class="kw">if</span> <span class="self">self</span>.<span class="ident">num_bits</span> <span class="op"><</span> <span class="ident">LUT_BITS</span> {
<span class="self">self</span>.<span class="ident">read_bits</span>(<span class="ident">reader</span>)<span class="question-mark">?</span>;
}
<span class="kw">let</span> (<span class="ident">value</span>, <span class="ident">run_size</span>) <span class="op">=</span> <span class="ident">ac_lut</span>[<span class="self">self</span>.<span class="ident">peek_bits</span>(<span class="ident">LUT_BITS</span>) <span class="kw">as</span> <span class="ident">usize</span>];
<span class="kw">if</span> <span class="ident">run_size</span> <span class="op">!</span><span class="op">=</span> <span class="number">0</span> {
<span class="kw">let</span> <span class="ident">run</span> <span class="op">=</span> <span class="ident">run_size</span> <span class="op">></span><span class="op">></span> <span class="number">4</span>;
<span class="kw">let</span> <span class="ident">size</span> <span class="op">=</span> <span class="ident">run_size</span> <span class="op">&</span> <span class="number">0x0f</span>;
<span class="self">self</span>.<span class="ident">consume_bits</span>(<span class="ident">size</span>);
<span class="kw">return</span> <span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>((<span class="ident">value</span>, <span class="ident">run</span>)));
}
}
<span class="prelude-val">Ok</span>(<span class="prelude-val">None</span>)
}
<span class="attribute">#[<span class="ident">inline</span>]</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">get_bits</span><span class="op"><</span><span class="ident">R</span>: <span class="ident">Read</span><span class="op">></span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>, <span class="ident">reader</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">R</span>, <span class="ident">count</span>: <span class="ident">u8</span>) <span class="op">-</span><span class="op">></span> <span class="prelude-ty">Result</span><span class="op"><</span><span class="ident">u16</span><span class="op">></span> {
<span class="kw">if</span> <span class="self">self</span>.<span class="ident">num_bits</span> <span class="op"><</span> <span class="ident">count</span> {
<span class="self">self</span>.<span class="ident">read_bits</span>(<span class="ident">reader</span>)<span class="question-mark">?</span>;
}
<span class="kw">let</span> <span class="ident">bits</span> <span class="op">=</span> <span class="self">self</span>.<span class="ident">peek_bits</span>(<span class="ident">count</span>);
<span class="self">self</span>.<span class="ident">consume_bits</span>(<span class="ident">count</span>);
<span class="prelude-val">Ok</span>(<span class="ident">bits</span>)
}
<span class="attribute">#[<span class="ident">inline</span>]</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">receive_extend</span><span class="op"><</span><span class="ident">R</span>: <span class="ident">Read</span><span class="op">></span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>, <span class="ident">reader</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">R</span>, <span class="ident">count</span>: <span class="ident">u8</span>) <span class="op">-</span><span class="op">></span> <span class="prelude-ty">Result</span><span class="op"><</span><span class="ident">i16</span><span class="op">></span> {
<span class="kw">let</span> <span class="ident">value</span> <span class="op">=</span> <span class="self">self</span>.<span class="ident">get_bits</span>(<span class="ident">reader</span>, <span class="ident">count</span>)<span class="question-mark">?</span>;
<span class="prelude-val">Ok</span>(<span class="ident">extend</span>(<span class="ident">value</span>, <span class="ident">count</span>))
}
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">reset</span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>) {
<span class="self">self</span>.<span class="ident">bits</span> <span class="op">=</span> <span class="number">0</span>;
<span class="self">self</span>.<span class="ident">num_bits</span> <span class="op">=</span> <span class="number">0</span>;
}
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">take_marker</span><span class="op"><</span><span class="ident">R</span>: <span class="ident">Read</span><span class="op">></span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>, <span class="ident">reader</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">R</span>) <span class="op">-</span><span class="op">></span> <span class="prelude-ty">Result</span><span class="op"><</span><span class="prelude-ty">Option</span><span class="op"><</span><span class="ident">Marker</span><span class="op">></span><span class="op">></span> {
<span class="self">self</span>.<span class="ident">read_bits</span>(<span class="ident">reader</span>).<span class="ident">map</span>(<span class="op">|</span><span class="kw">_</span><span class="op">|</span> <span class="self">self</span>.<span class="ident">marker</span>.<span class="ident">take</span>())
}
<span class="attribute">#[<span class="ident">inline</span>]</span>
<span class="kw">fn</span> <span class="ident">peek_bits</span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>, <span class="ident">count</span>: <span class="ident">u8</span>) <span class="op">-</span><span class="op">></span> <span class="ident">u16</span> {
<span class="macro">debug_assert!</span>(<span class="ident">count</span> <span class="op"><</span><span class="op">=</span> <span class="number">16</span>);
<span class="macro">debug_assert!</span>(<span class="self">self</span>.<span class="ident">num_bits</span> <span class="op">></span><span class="op">=</span> <span class="ident">count</span>);
((<span class="self">self</span>.<span class="ident">bits</span> <span class="op">></span><span class="op">></span> (<span class="number">64</span> <span class="op">-</span> <span class="ident">count</span>)) <span class="op">&</span> ((<span class="number">1</span> <span class="op"><</span><span class="op"><</span> <span class="ident">count</span>) <span class="op">-</span> <span class="number">1</span>)) <span class="kw">as</span> <span class="ident">u16</span>
}
<span class="attribute">#[<span class="ident">inline</span>]</span>
<span class="kw">fn</span> <span class="ident">consume_bits</span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>, <span class="ident">count</span>: <span class="ident">u8</span>) {
<span class="macro">debug_assert!</span>(<span class="self">self</span>.<span class="ident">num_bits</span> <span class="op">></span><span class="op">=</span> <span class="ident">count</span>);
<span class="self">self</span>.<span class="ident">bits</span> <span class="op"><</span><span class="op"><</span><span class="op">=</span> <span class="ident">count</span> <span class="kw">as</span> <span class="ident">usize</span>;
<span class="self">self</span>.<span class="ident">num_bits</span> <span class="op">-</span><span class="op">=</span> <span class="ident">count</span>;
}
<span class="kw">fn</span> <span class="ident">read_bits</span><span class="op"><</span><span class="ident">R</span>: <span class="ident">Read</span><span class="op">></span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>, <span class="ident">reader</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">R</span>) <span class="op">-</span><span class="op">></span> <span class="prelude-ty">Result</span><span class="op"><</span>()<span class="op">></span> {
<span class="kw">while</span> <span class="self">self</span>.<span class="ident">num_bits</span> <span class="op"><</span><span class="op">=</span> <span class="number">56</span> {
<span class="comment">// Fill with zero bits if we have reached the end.</span>
<span class="kw">let</span> <span class="ident">byte</span> <span class="op">=</span> <span class="kw">match</span> <span class="self">self</span>.<span class="ident">marker</span> {
<span class="prelude-val">Some</span>(<span class="kw">_</span>) <span class="op">=</span><span class="op">></span> <span class="number">0</span>,
<span class="prelude-val">None</span> <span class="op">=</span><span class="op">></span> <span class="ident">read_u8</span>(<span class="ident">reader</span>)<span class="question-mark">?</span>,
};
<span class="kw">if</span> <span class="ident">byte</span> <span class="op">=</span><span class="op">=</span> <span class="number">0xFF</span> {
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">next_byte</span> <span class="op">=</span> <span class="ident">read_u8</span>(<span class="ident">reader</span>)<span class="question-mark">?</span>;
<span class="comment">// Check for byte stuffing.</span>
<span class="kw">if</span> <span class="ident">next_byte</span> <span class="op">!</span><span class="op">=</span> <span class="number">0x00</span> {
<span class="comment">// We seem to have reached the end of entropy-coded data and encountered a</span>
<span class="comment">// marker. Since we can't put data back into the reader, we have to continue</span>
<span class="comment">// reading to identify the marker so we can pass it on.</span>
<span class="comment">// Section B.1.1.2</span>
<span class="comment">// "Any marker may optionally be preceded by any number of fill bytes, which are bytes assigned code X’FF’."</span>
<span class="kw">while</span> <span class="ident">next_byte</span> <span class="op">=</span><span class="op">=</span> <span class="number">0xFF</span> {
<span class="ident">next_byte</span> <span class="op">=</span> <span class="ident">read_u8</span>(<span class="ident">reader</span>)<span class="question-mark">?</span>;
}
<span class="kw">match</span> <span class="ident">next_byte</span> {
<span class="number">0x00</span> <span class="op">=</span><span class="op">></span> <span class="kw">return</span> <span class="prelude-val">Err</span>(<span class="ident">Error::Format</span>(<span class="string">"FF 00 found where marker was expected"</span>.<span class="ident">to_owned</span>())),
<span class="kw">_</span> <span class="op">=</span><span class="op">></span> <span class="self">self</span>.<span class="ident">marker</span> <span class="op">=</span> <span class="prelude-val">Some</span>(<span class="ident">Marker::from_u8</span>(<span class="ident">next_byte</span>).<span class="ident">unwrap</span>()),
}
<span class="kw">continue</span>;
}
}
<span class="self">self</span>.<span class="ident">bits</span> <span class="op">|</span><span class="op">=</span> (<span class="ident">byte</span> <span class="kw">as</span> <span class="ident">u64</span>) <span class="op"><</span><span class="op"><</span> (<span class="number">56</span> <span class="op">-</span> <span class="self">self</span>.<span class="ident">num_bits</span>);
<span class="self">self</span>.<span class="ident">num_bits</span> <span class="op">+</span><span class="op">=</span> <span class="number">8</span>;
}
<span class="prelude-val">Ok</span>(())
}
}
<span class="comment">// Section F.2.2.1</span>
<span class="comment">// Figure F.12</span>
<span class="kw">fn</span> <span class="ident">extend</span>(<span class="ident">value</span>: <span class="ident">u16</span>, <span class="ident">count</span>: <span class="ident">u8</span>) <span class="op">-</span><span class="op">></span> <span class="ident">i16</span> {
<span class="kw">let</span> <span class="ident">vt</span> <span class="op">=</span> <span class="number">1</span> <span class="op"><</span><span class="op"><</span> (<span class="ident">count</span> <span class="kw">as</span> <span class="ident">u16</span> <span class="op">-</span> <span class="number">1</span>);
<span class="kw">if</span> <span class="ident">value</span> <span class="op"><</span> <span class="ident">vt</span> {
<span class="ident">value</span> <span class="kw">as</span> <span class="ident">i16</span> <span class="op">+</span> (<span class="op">-</span><span class="number">1</span> <span class="op"><</span><span class="op"><</span> <span class="ident">count</span> <span class="kw">as</span> <span class="ident">i16</span>) <span class="op">+</span> <span class="number">1</span>
} <span class="kw">else</span> {
<span class="ident">value</span> <span class="kw">as</span> <span class="ident">i16</span>
}
}
<span class="attribute">#[<span class="ident">derive</span>(<span class="ident">Clone</span>, <span class="ident">Copy</span>, <span class="ident">Debug</span>, <span class="ident">PartialEq</span>)]</span>
<span class="kw">pub</span> <span class="kw">enum</span> <span class="ident">HuffmanTableClass</span> {
<span class="ident">DC</span>,
<span class="ident">AC</span>,
}
<span class="kw">pub</span> <span class="kw">struct</span> <span class="ident">HuffmanTable</span> {
<span class="ident">values</span>: <span class="ident">Vec</span><span class="op"><</span><span class="ident">u8</span><span class="op">></span>,
<span class="ident">delta</span>: [<span class="ident">i32</span>; <span class="number">16</span>],
<span class="ident">maxcode</span>: [<span class="ident">i32</span>; <span class="number">16</span>],
<span class="ident">lut</span>: [(<span class="ident">u8</span>, <span class="ident">u8</span>); <span class="number">1</span> <span class="op"><</span><span class="op"><</span> <span class="ident">LUT_BITS</span>],
<span class="ident">ac_lut</span>: <span class="prelude-ty">Option</span><span class="op"><</span>[(<span class="ident">i16</span>, <span class="ident">u8</span>); <span class="number">1</span> <span class="op"><</span><span class="op"><</span> <span class="ident">LUT_BITS</span>]<span class="op">></span>,
}
<span class="kw">impl</span> <span class="ident">HuffmanTable</span> {
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">new</span>(<span class="ident">bits</span>: <span class="kw-2">&</span>[<span class="ident">u8</span>; <span class="number">16</span>], <span class="ident">values</span>: <span class="kw-2">&</span>[<span class="ident">u8</span>], <span class="ident">class</span>: <span class="ident">HuffmanTableClass</span>) <span class="op">-</span><span class="op">></span> <span class="prelude-ty">Result</span><span class="op"><</span><span class="ident">HuffmanTable</span><span class="op">></span> {
<span class="kw">let</span> (<span class="ident">huffcode</span>, <span class="ident">huffsize</span>) <span class="op">=</span> <span class="ident">derive_huffman_codes</span>(<span class="ident">bits</span>)<span class="question-mark">?</span>;
<span class="comment">// Section F.2.2.3</span>
<span class="comment">// Figure F.15</span>
<span class="comment">// delta[i] is set to VALPTR(I) - MINCODE(I)</span>
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">delta</span> <span class="op">=</span> [<span class="number">0i32</span>; <span class="number">16</span>];
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">maxcode</span> <span class="op">=</span> [<span class="op">-</span><span class="number">1i32</span>; <span class="number">16</span>];
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">j</span> <span class="op">=</span> <span class="number">0</span>;
<span class="kw">for</span> <span class="ident">i</span> <span class="kw">in</span> <span class="number">0</span> .. <span class="number">16</span> {
<span class="kw">if</span> <span class="ident">bits</span>[<span class="ident">i</span>] <span class="op">!</span><span class="op">=</span> <span class="number">0</span> {
<span class="ident">delta</span>[<span class="ident">i</span>] <span class="op">=</span> <span class="ident">j</span> <span class="kw">as</span> <span class="ident">i32</span> <span class="op">-</span> <span class="ident">huffcode</span>[<span class="ident">j</span>] <span class="kw">as</span> <span class="ident">i32</span>;
<span class="ident">j</span> <span class="op">+</span><span class="op">=</span> <span class="ident">bits</span>[<span class="ident">i</span>] <span class="kw">as</span> <span class="ident">usize</span>;
<span class="ident">maxcode</span>[<span class="ident">i</span>] <span class="op">=</span> <span class="ident">huffcode</span>[<span class="ident">j</span> <span class="op">-</span> <span class="number">1</span>] <span class="kw">as</span> <span class="ident">i32</span>;
}
}
<span class="comment">// Build a lookup table for faster decoding.</span>
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">lut</span> <span class="op">=</span> [(<span class="number">0u8</span>, <span class="number">0u8</span>); <span class="number">1</span> <span class="op"><</span><span class="op"><</span> <span class="ident">LUT_BITS</span>];
<span class="kw">for</span> (<span class="ident">i</span>, <span class="kw-2">&</span><span class="ident">size</span>) <span class="kw">in</span> <span class="ident">huffsize</span>.<span class="ident">iter</span>().<span class="ident">enumerate</span>().<span class="ident">filter</span>(<span class="op">|</span><span class="kw-2">&</span>(<span class="kw">_</span>, <span class="kw-2">&</span><span class="ident">size</span>)<span class="op">|</span> <span class="ident">size</span> <span class="op"><</span><span class="op">=</span> <span class="ident">LUT_BITS</span>) {
<span class="kw">let</span> <span class="ident">bits_remaining</span> <span class="op">=</span> <span class="ident">LUT_BITS</span> <span class="op">-</span> <span class="ident">size</span>;
<span class="kw">let</span> <span class="ident">start</span> <span class="op">=</span> (<span class="ident">huffcode</span>[<span class="ident">i</span>] <span class="op"><</span><span class="op"><</span> <span class="ident">bits_remaining</span>) <span class="kw">as</span> <span class="ident">usize</span>;
<span class="kw">for</span> <span class="ident">j</span> <span class="kw">in</span> <span class="number">0</span> .. <span class="number">1</span> <span class="op"><</span><span class="op"><</span> <span class="ident">bits_remaining</span> {
<span class="ident">lut</span>[<span class="ident">start</span> <span class="op">+</span> <span class="ident">j</span>] <span class="op">=</span> (<span class="ident">values</span>[<span class="ident">i</span>], <span class="ident">size</span>);
}
}
<span class="comment">// Build a lookup table for small AC coefficients which both decodes the value and does the</span>
<span class="comment">// equivalent of receive_extend.</span>
<span class="kw">let</span> <span class="ident">ac_lut</span> <span class="op">=</span> <span class="kw">match</span> <span class="ident">class</span> {
<span class="ident">HuffmanTableClass::DC</span> <span class="op">=</span><span class="op">></span> <span class="prelude-val">None</span>,
<span class="ident">HuffmanTableClass::AC</span> <span class="op">=</span><span class="op">></span> {
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">table</span> <span class="op">=</span> [(<span class="number">0i16</span>, <span class="number">0u8</span>); <span class="number">1</span> <span class="op"><</span><span class="op"><</span> <span class="ident">LUT_BITS</span>];
<span class="kw">for</span> (<span class="ident">i</span>, <span class="kw-2">&</span>(<span class="ident">value</span>, <span class="ident">size</span>)) <span class="kw">in</span> <span class="ident">lut</span>.<span class="ident">iter</span>().<span class="ident">enumerate</span>() {
<span class="kw">let</span> <span class="ident">run_length</span> <span class="op">=</span> <span class="ident">value</span> <span class="op">></span><span class="op">></span> <span class="number">4</span>;
<span class="kw">let</span> <span class="ident">magnitude_category</span> <span class="op">=</span> <span class="ident">value</span> <span class="op">&</span> <span class="number">0x0f</span>;
<span class="kw">if</span> <span class="ident">magnitude_category</span> <span class="op">></span> <span class="number">0</span> <span class="op">&&</span> <span class="ident">size</span> <span class="op">+</span> <span class="ident">magnitude_category</span> <span class="op"><</span><span class="op">=</span> <span class="ident">LUT_BITS</span> {
<span class="kw">let</span> <span class="ident">unextended_ac_value</span> <span class="op">=</span> (((<span class="ident">i</span> <span class="op"><</span><span class="op"><</span> <span class="ident">size</span>) <span class="op">&</span> ((<span class="number">1</span> <span class="op"><</span><span class="op"><</span> <span class="ident">LUT_BITS</span>) <span class="op">-</span> <span class="number">1</span>)) <span class="op">></span><span class="op">></span> (<span class="ident">LUT_BITS</span> <span class="op">-</span> <span class="ident">magnitude_category</span>)) <span class="kw">as</span> <span class="ident">u16</span>;
<span class="kw">let</span> <span class="ident">ac_value</span> <span class="op">=</span> <span class="ident">extend</span>(<span class="ident">unextended_ac_value</span>, <span class="ident">magnitude_category</span>);
<span class="ident">table</span>[<span class="ident">i</span>] <span class="op">=</span> (<span class="ident">ac_value</span>, (<span class="ident">run_length</span> <span class="op"><</span><span class="op"><</span> <span class="number">4</span>) <span class="op">|</span> (<span class="ident">size</span> <span class="op">+</span> <span class="ident">magnitude_category</span>));
}
}
<span class="prelude-val">Some</span>(<span class="ident">table</span>)
},
};
<span class="prelude-val">Ok</span>(<span class="ident">HuffmanTable</span> {
<span class="ident">values</span>: <span class="ident">values</span>.<span class="ident">to_vec</span>(),
<span class="ident">delta</span>: <span class="ident">delta</span>,
<span class="ident">maxcode</span>: <span class="ident">maxcode</span>,
<span class="ident">lut</span>: <span class="ident">lut</span>,
<span class="ident">ac_lut</span>: <span class="ident">ac_lut</span>,
})
}
}
<span class="comment">// Section C.2</span>
<span class="kw">fn</span> <span class="ident">derive_huffman_codes</span>(<span class="ident">bits</span>: <span class="kw-2">&</span>[<span class="ident">u8</span>; <span class="number">16</span>]) <span class="op">-</span><span class="op">></span> <span class="prelude-ty">Result</span><span class="op"><</span>(<span class="ident">Vec</span><span class="op"><</span><span class="ident">u16</span><span class="op">></span>, <span class="ident">Vec</span><span class="op"><</span><span class="ident">u8</span><span class="op">></span>)<span class="op">></span> {
<span class="comment">// Figure C.1</span>
<span class="kw">let</span> <span class="ident">huffsize</span> <span class="op">=</span> <span class="ident">bits</span>.<span class="ident">iter</span>()
.<span class="ident">enumerate</span>()
.<span class="ident">fold</span>(<span class="ident">Vec::new</span>(), <span class="op">|</span><span class="kw-2">mut</span> <span class="ident">acc</span>, (<span class="ident">i</span>, <span class="kw-2">&</span><span class="ident">value</span>)<span class="op">|</span> {
<span class="ident">acc</span>.<span class="ident">extend</span>(<span class="ident">std::iter::repeat</span>((<span class="ident">i</span> <span class="op">+</span> <span class="number">1</span>) <span class="kw">as</span> <span class="ident">u8</span>).<span class="ident">take</span>(<span class="ident">value</span> <span class="kw">as</span> <span class="ident">usize</span>));
<span class="ident">acc</span>
});
<span class="comment">// Figure C.2</span>
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">huffcode</span> <span class="op">=</span> <span class="macro">vec!</span>[<span class="number">0u16</span>; <span class="ident">huffsize</span>.<span class="ident">len</span>()];
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">code_size</span> <span class="op">=</span> <span class="ident">huffsize</span>[<span class="number">0</span>];
<span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">code</span> <span class="op">=</span> <span class="number">0u32</span>;
<span class="kw">for</span> (<span class="ident">i</span>, <span class="kw-2">&</span><span class="ident">size</span>) <span class="kw">in</span> <span class="ident">huffsize</span>.<span class="ident">iter</span>().<span class="ident">enumerate</span>() {
<span class="kw">while</span> <span class="ident">code_size</span> <span class="op"><</span> <span class="ident">size</span> {
<span class="ident">code</span> <span class="op"><</span><span class="op"><</span><span class="op">=</span> <span class="number">1</span>;
<span class="ident">code_size</span> <span class="op">+</span><span class="op">=</span> <span class="number">1</span>;
}
<span class="kw">if</span> <span class="ident">code</span> <span class="op">></span><span class="op">=</span> (<span class="number">1u32</span> <span class="op"><</span><span class="op"><</span> <span class="ident">size</span>) {
<span class="kw">return</span> <span class="prelude-val">Err</span>(<span class="ident">Error::Format</span>(<span class="string">"bad huffman code length"</span>.<span class="ident">to_owned</span>()));
}
<span class="ident">huffcode</span>[<span class="ident">i</span>] <span class="op">=</span> <span class="ident">code</span> <span class="kw">as</span> <span class="ident">u16</span>;
<span class="ident">code</span> <span class="op">+</span><span class="op">=</span> <span class="number">1</span>;
}
<span class="prelude-val">Ok</span>((<span class="ident">huffcode</span>, <span class="ident">huffsize</span>))
}
<span class="comment">// https://www.loc.gov/preservation/digital/formats/fdd/fdd000063.shtml</span>
<span class="comment">// "Avery Lee, writing in the rec.video.desktop newsgroup in 2001, commented that "MJPEG, or at</span>
<span class="comment">// least the MJPEG in AVIs having the MJPG fourcc, is restricted JPEG with a fixed -- and</span>
<span class="comment">// *omitted* -- Huffman table. The JPEG must be YCbCr colorspace, it must be 4:2:2, and it must</span>
<span class="comment">// use basic Huffman encoding, not arithmetic or progressive.... You can indeed extract the</span>
<span class="comment">// MJPEG frames and decode them with a regular JPEG decoder, but you have to prepend the DHT</span>
<span class="comment">// segment to them, or else the decoder won't have any idea how to decompress the data.</span>
<span class="comment">// The exact table necessary is given in the OpenDML spec.""</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">fill_default_mjpeg_tables</span>(<span class="ident">scan</span>: <span class="kw-2">&</span><span class="ident">ScanInfo</span>,
<span class="ident">dc_huffman_tables</span>: <span class="kw-2">&</span><span class="kw-2">mut</span>[<span class="prelude-ty">Option</span><span class="op"><</span><span class="ident">HuffmanTable</span><span class="op">></span>],
<span class="ident">ac_huffman_tables</span>: <span class="kw-2">&</span><span class="kw-2">mut</span>[<span class="prelude-ty">Option</span><span class="op"><</span><span class="ident">HuffmanTable</span><span class="op">></span>]) {
<span class="comment">// Section K.3.3</span>
<span class="kw">if</span> <span class="ident">dc_huffman_tables</span>[<span class="number">0</span>].<span class="ident">is_none</span>() <span class="op">&&</span> <span class="ident">scan</span>.<span class="ident">dc_table_indices</span>.<span class="ident">iter</span>().<span class="ident">any</span>(<span class="op">|</span><span class="kw-2">&</span><span class="ident">i</span><span class="op">|</span> <span class="ident">i</span> <span class="op">=</span><span class="op">=</span> <span class="number">0</span>) {
<span class="comment">// Table K.3</span>
<span class="ident">dc_huffman_tables</span>[<span class="number">0</span>] <span class="op">=</span> <span class="prelude-val">Some</span>(<span class="ident">HuffmanTable::new</span>(
<span class="kw-2">&</span>[<span class="number">0x00</span>, <span class="number">0x01</span>, <span class="number">0x05</span>, <span class="number">0x01</span>, <span class="number">0x01</span>, <span class="number">0x01</span>, <span class="number">0x01</span>, <span class="number">0x01</span>, <span class="number">0x01</span>, <span class="number">0x00</span>, <span class="number">0x00</span>, <span class="number">0x00</span>, <span class="number">0x00</span>, <span class="number">0x00</span>, <span class="number">0x00</span>, <span class="number">0x00</span>],
<span class="kw-2">&</span>[<span class="number">0x00</span>, <span class="number">0x01</span>, <span class="number">0x02</span>, <span class="number">0x03</span>, <span class="number">0x04</span>, <span class="number">0x05</span>, <span class="number">0x06</span>, <span class="number">0x07</span>, <span class="number">0x08</span>, <span class="number">0x09</span>, <span class="number">0x0A</span>, <span class="number">0x0B</span>], <span class="ident">HuffmanTableClass::DC</span>).<span class="ident">unwrap</span>());
}
<span class="kw">if</span> <span class="ident">dc_huffman_tables</span>[<span class="number">1</span>].<span class="ident">is_none</span>() <span class="op">&&</span> <span class="ident">scan</span>.<span class="ident">dc_table_indices</span>.<span class="ident">iter</span>().<span class="ident">any</span>(<span class="op">|</span><span class="kw-2">&</span><span class="ident">i</span><span class="op">|</span> <span class="ident">i</span> <span class="op">=</span><span class="op">=</span> <span class="number">1</span>) {
<span class="comment">// Table K.4</span>
<span class="ident">dc_huffman_tables</span>[<span class="number">1</span>] <span class="op">=</span> <span class="prelude-val">Some</span>(<span class="ident">HuffmanTable::new</span>(
<span class="kw-2">&</span>[<span class="number">0x00</span>, <span class="number">0x03</span>, <span class="number">0x01</span>, <span class="number">0x01</span>, <span class="number">0x01</span>, <span class="number">0x01</span>, <span class="number">0x01</span>, <span class="number">0x01</span>, <span class="number">0x01</span>, <span class="number">0x01</span>, <span class="number">0x01</span>, <span class="number">0x00</span>, <span class="number">0x00</span>, <span class="number">0x00</span>, <span class="number">0x00</span>, <span class="number">0x00</span>],
<span class="kw-2">&</span>[<span class="number">0x00</span>, <span class="number">0x01</span>, <span class="number">0x02</span>, <span class="number">0x03</span>, <span class="number">0x04</span>, <span class="number">0x05</span>, <span class="number">0x06</span>, <span class="number">0x07</span>, <span class="number">0x08</span>, <span class="number">0x09</span>, <span class="number">0x0A</span>, <span class="number">0x0B</span>], <span class="ident">HuffmanTableClass::DC</span>).<span class="ident">unwrap</span>());
}
<span class="kw">if</span> <span class="ident">ac_huffman_tables</span>[<span class="number">0</span>].<span class="ident">is_none</span>() <span class="op">&&</span> <span class="ident">scan</span>.<span class="ident">ac_table_indices</span>.<span class="ident">iter</span>().<span class="ident">any</span>(<span class="op">|</span><span class="kw-2">&</span><span class="ident">i</span><span class="op">|</span> <span class="ident">i</span> <span class="op">=</span><span class="op">=</span> <span class="number">0</span>) {
<span class="comment">// Table K.5</span>
<span class="ident">ac_huffman_tables</span>[<span class="number">0</span>] <span class="op">=</span> <span class="prelude-val">Some</span>(<span class="ident">HuffmanTable::new</span>(
<span class="kw-2">&</span>[<span class="number">0x00</span>, <span class="number">0x02</span>, <span class="number">0x01</span>, <span class="number">0x03</span>, <span class="number">0x03</span>, <span class="number">0x02</span>, <span class="number">0x04</span>, <span class="number">0x03</span>, <span class="number">0x05</span>, <span class="number">0x05</span>, <span class="number">0x04</span>, <span class="number">0x04</span>, <span class="number">0x00</span>, <span class="number">0x00</span>, <span class="number">0x01</span>, <span class="number">0x7D</span>],
<span class="kw-2">&</span>[<span class="number">0x01</span>, <span class="number">0x02</span>, <span class="number">0x03</span>, <span class="number">0x00</span>, <span class="number">0x04</span>, <span class="number">0x11</span>, <span class="number">0x05</span>, <span class="number">0x12</span>, <span class="number">0x21</span>, <span class="number">0x31</span>, <span class="number">0x41</span>, <span class="number">0x06</span>, <span class="number">0x13</span>, <span class="number">0x51</span>, <span class="number">0x61</span>, <span class="number">0x07</span>,
<span class="number">0x22</span>, <span class="number">0x71</span>, <span class="number">0x14</span>, <span class="number">0x32</span>, <span class="number">0x81</span>, <span class="number">0x91</span>, <span class="number">0xA1</span>, <span class="number">0x08</span>, <span class="number">0x23</span>, <span class="number">0x42</span>, <span class="number">0xB1</span>, <span class="number">0xC1</span>, <span class="number">0x15</span>, <span class="number">0x52</span>, <span class="number">0xD1</span>, <span class="number">0xF0</span>,
<span class="number">0x24</span>, <span class="number">0x33</span>, <span class="number">0x62</span>, <span class="number">0x72</span>, <span class="number">0x82</span>, <span class="number">0x09</span>, <span class="number">0x0A</span>, <span class="number">0x16</span>, <span class="number">0x17</span>, <span class="number">0x18</span>, <span class="number">0x19</span>, <span class="number">0x1A</span>, <span class="number">0x25</span>, <span class="number">0x26</span>, <span class="number">0x27</span>, <span class="number">0x28</span>,
<span class="number">0x29</span>, <span class="number">0x2A</span>, <span class="number">0x34</span>, <span class="number">0x35</span>, <span class="number">0x36</span>, <span class="number">0x37</span>, <span class="number">0x38</span>, <span class="number">0x39</span>, <span class="number">0x3A</span>, <span class="number">0x43</span>, <span class="number">0x44</span>, <span class="number">0x45</span>, <span class="number">0x46</span>, <span class="number">0x47</span>, <span class="number">0x48</span>, <span class="number">0x49</span>,
<span class="number">0x4A</span>, <span class="number">0x53</span>, <span class="number">0x54</span>, <span class="number">0x55</span>, <span class="number">0x56</span>, <span class="number">0x57</span>, <span class="number">0x58</span>, <span class="number">0x59</span>, <span class="number">0x5A</span>, <span class="number">0x63</span>, <span class="number">0x64</span>, <span class="number">0x65</span>, <span class="number">0x66</span>, <span class="number">0x67</span>, <span class="number">0x68</span>, <span class="number">0x69</span>,
<span class="number">0x6A</span>, <span class="number">0x73</span>, <span class="number">0x74</span>, <span class="number">0x75</span>, <span class="number">0x76</span>, <span class="number">0x77</span>, <span class="number">0x78</span>, <span class="number">0x79</span>, <span class="number">0x7A</span>, <span class="number">0x83</span>, <span class="number">0x84</span>, <span class="number">0x85</span>, <span class="number">0x86</span>, <span class="number">0x87</span>, <span class="number">0x88</span>, <span class="number">0x89</span>,
<span class="number">0x8A</span>, <span class="number">0x92</span>, <span class="number">0x93</span>, <span class="number">0x94</span>, <span class="number">0x95</span>, <span class="number">0x96</span>, <span class="number">0x97</span>, <span class="number">0x98</span>, <span class="number">0x99</span>, <span class="number">0x9A</span>, <span class="number">0xA2</span>, <span class="number">0xA3</span>, <span class="number">0xA4</span>, <span class="number">0xA5</span>, <span class="number">0xA6</span>, <span class="number">0xA7</span>,
<span class="number">0xA8</span>, <span class="number">0xA9</span>, <span class="number">0xAA</span>, <span class="number">0xB2</span>, <span class="number">0xB3</span>, <span class="number">0xB4</span>, <span class="number">0xB5</span>, <span class="number">0xB6</span>, <span class="number">0xB7</span>, <span class="number">0xB8</span>, <span class="number">0xB9</span>, <span class="number">0xBA</span>, <span class="number">0xC2</span>, <span class="number">0xC3</span>, <span class="number">0xC4</span>, <span class="number">0xC5</span>,
<span class="number">0xC6</span>, <span class="number">0xC7</span>, <span class="number">0xC8</span>, <span class="number">0xC9</span>, <span class="number">0xCA</span>, <span class="number">0xD2</span>, <span class="number">0xD3</span>, <span class="number">0xD4</span>, <span class="number">0xD5</span>, <span class="number">0xD6</span>, <span class="number">0xD7</span>, <span class="number">0xD8</span>, <span class="number">0xD9</span>, <span class="number">0xDA</span>, <span class="number">0xE1</span>, <span class="number">0xE2</span>,
<span class="number">0xE3</span>, <span class="number">0xE4</span>, <span class="number">0xE5</span>, <span class="number">0xE6</span>, <span class="number">0xE7</span>, <span class="number">0xE8</span>, <span class="number">0xE9</span>, <span class="number">0xEA</span>, <span class="number">0xF1</span>, <span class="number">0xF2</span>, <span class="number">0xF3</span>, <span class="number">0xF4</span>, <span class="number">0xF5</span>, <span class="number">0xF6</span>, <span class="number">0xF7</span>, <span class="number">0xF8</span>,
<span class="number">0xF9</span>, <span class="number">0xFA</span>
], <span class="ident">HuffmanTableClass::AC</span>).<span class="ident">unwrap</span>());
}
<span class="kw">if</span> <span class="ident">ac_huffman_tables</span>[<span class="number">1</span>].<span class="ident">is_none</span>() <span class="op">&&</span> <span class="ident">scan</span>.<span class="ident">ac_table_indices</span>.<span class="ident">iter</span>().<span class="ident">any</span>(<span class="op">|</span><span class="kw-2">&</span><span class="ident">i</span><span class="op">|</span> <span class="ident">i</span> <span class="op">=</span><span class="op">=</span> <span class="number">1</span>) {
<span class="comment">// Table K.6</span>
<span class="ident">ac_huffman_tables</span>[<span class="number">1</span>] <span class="op">=</span> <span class="prelude-val">Some</span>(<span class="ident">HuffmanTable::new</span>(
<span class="kw-2">&</span>[<span class="number">0x00</span>, <span class="number">0x02</span>, <span class="number">0x01</span>, <span class="number">0x02</span>, <span class="number">0x04</span>, <span class="number">0x04</span>, <span class="number">0x03</span>, <span class="number">0x04</span>, <span class="number">0x07</span>, <span class="number">0x05</span>, <span class="number">0x04</span>, <span class="number">0x04</span>, <span class="number">0x00</span>, <span class="number">0x01</span>, <span class="number">0x02</span>, <span class="number">0x77</span>],
<span class="kw-2">&</span>[<span class="number">0x00</span>, <span class="number">0x01</span>, <span class="number">0x02</span>, <span class="number">0x03</span>, <span class="number">0x11</span>, <span class="number">0x04</span>, <span class="number">0x05</span>, <span class="number">0x21</span>, <span class="number">0x31</span>, <span class="number">0x06</span>, <span class="number">0x12</span>, <span class="number">0x41</span>, <span class="number">0x51</span>, <span class="number">0x07</span>, <span class="number">0x61</span>, <span class="number">0x71</span>,
<span class="number">0x13</span>, <span class="number">0x22</span>, <span class="number">0x32</span>, <span class="number">0x81</span>, <span class="number">0x08</span>, <span class="number">0x14</span>, <span class="number">0x42</span>, <span class="number">0x91</span>, <span class="number">0xA1</span>, <span class="number">0xB1</span>, <span class="number">0xC1</span>, <span class="number">0x09</span>, <span class="number">0x23</span>, <span class="number">0x33</span>, <span class="number">0x52</span>, <span class="number">0xF0</span>,
<span class="number">0x15</span>, <span class="number">0x62</span>, <span class="number">0x72</span>, <span class="number">0xD1</span>, <span class="number">0x0A</span>, <span class="number">0x16</span>, <span class="number">0x24</span>, <span class="number">0x34</span>, <span class="number">0xE1</span>, <span class="number">0x25</span>, <span class="number">0xF1</span>, <span class="number">0x17</span>, <span class="number">0x18</span>, <span class="number">0x19</span>, <span class="number">0x1A</span>, <span class="number">0x26</span>,
<span class="number">0x27</span>, <span class="number">0x28</span>, <span class="number">0x29</span>, <span class="number">0x2A</span>, <span class="number">0x35</span>, <span class="number">0x36</span>, <span class="number">0x37</span>, <span class="number">0x38</span>, <span class="number">0x39</span>, <span class="number">0x3A</span>, <span class="number">0x43</span>, <span class="number">0x44</span>, <span class="number">0x45</span>, <span class="number">0x46</span>, <span class="number">0x47</span>, <span class="number">0x48</span>,
<span class="number">0x49</span>, <span class="number">0x4A</span>, <span class="number">0x53</span>, <span class="number">0x54</span>, <span class="number">0x55</span>, <span class="number">0x56</span>, <span class="number">0x57</span>, <span class="number">0x58</span>, <span class="number">0x59</span>, <span class="number">0x5A</span>, <span class="number">0x63</span>, <span class="number">0x64</span>, <span class="number">0x65</span>, <span class="number">0x66</span>, <span class="number">0x67</span>, <span class="number">0x68</span>,
<span class="number">0x69</span>, <span class="number">0x6A</span>, <span class="number">0x73</span>, <span class="number">0x74</span>, <span class="number">0x75</span>, <span class="number">0x76</span>, <span class="number">0x77</span>, <span class="number">0x78</span>, <span class="number">0x79</span>, <span class="number">0x7A</span>, <span class="number">0x82</span>, <span class="number">0x83</span>, <span class="number">0x84</span>, <span class="number">0x85</span>, <span class="number">0x86</span>, <span class="number">0x87</span>,
<span class="number">0x88</span>, <span class="number">0x89</span>, <span class="number">0x8A</span>, <span class="number">0x92</span>, <span class="number">0x93</span>, <span class="number">0x94</span>, <span class="number">0x95</span>, <span class="number">0x96</span>, <span class="number">0x97</span>, <span class="number">0x98</span>, <span class="number">0x99</span>, <span class="number">0x9A</span>, <span class="number">0xA2</span>, <span class="number">0xA3</span>, <span class="number">0xA4</span>, <span class="number">0xA5</span>,
<span class="number">0xA6</span>, <span class="number">0xA7</span>, <span class="number">0xA8</span>, <span class="number">0xA9</span>, <span class="number">0xAA</span>, <span class="number">0xB2</span>, <span class="number">0xB3</span>, <span class="number">0xB4</span>, <span class="number">0xB5</span>, <span class="number">0xB6</span>, <span class="number">0xB7</span>, <span class="number">0xB8</span>, <span class="number">0xB9</span>, <span class="number">0xBA</span>, <span class="number">0xC2</span>, <span class="number">0xC3</span>,
<span class="number">0xC4</span>, <span class="number">0xC5</span>, <span class="number">0xC6</span>, <span class="number">0xC7</span>, <span class="number">0xC8</span>, <span class="number">0xC9</span>, <span class="number">0xCA</span>, <span class="number">0xD2</span>, <span class="number">0xD3</span>, <span class="number">0xD4</span>, <span class="number">0xD5</span>, <span class="number">0xD6</span>, <span class="number">0xD7</span>, <span class="number">0xD8</span>, <span class="number">0xD9</span>, <span class="number">0xDA</span>,
<span class="number">0xE2</span>, <span class="number">0xE3</span>, <span class="number">0xE4</span>, <span class="number">0xE5</span>, <span class="number">0xE6</span>, <span class="number">0xE7</span>, <span class="number">0xE8</span>, <span class="number">0xE9</span>, <span class="number">0xEA</span>, <span class="number">0xF2</span>, <span class="number">0xF3</span>, <span class="number">0xF4</span>, <span class="number">0xF5</span>, <span class="number">0xF6</span>, <span class="number">0xF7</span>, <span class="number">0xF8</span>,
<span class="number">0xF9</span>, <span class="number">0xFA</span>
], <span class="ident">HuffmanTableClass::AC</span>).<span class="ident">unwrap</span>());
}
}
</pre></div>
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