| <!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 `/root/.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="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Regular.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Medium.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Bold.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Semibold.ttf.woff2"><link rel="stylesheet" href="../../normalize.css"><link rel="stylesheet" href="../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" href="../../ayu.css" disabled><link rel="stylesheet" href="../../dark.css" disabled><link rel="stylesheet" href="../../light.css" id="themeStyle"><script id="default-settings" ></script><script src="../../storage.js"></script><script defer src="../../source-script.js"></script><script defer src="../../source-files.js"></script><script defer src="../../main.js"></script><noscript><link rel="stylesheet" href="../../noscript.css"></noscript><link rel="alternate icon" type="image/png" href="../../favicon-16x16.png"><link rel="alternate icon" type="image/png" href="../../favicon-32x32.png"><link rel="icon" type="image/svg+xml" href="../../favicon.svg"></head><body class="rustdoc source"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><a class="sidebar-logo" href="../../jpeg_decoder/index.html"><div class="logo-container"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></div></a></nav><main><div class="width-limiter"><nav class="sub"><a class="sub-logo-container" href="../../jpeg_decoder/index.html"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></a><form class="search-form"><div class="search-container"><span></span><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" title="help" tabindex="-1"><a href="../../help.html">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../wheel.svg"></a></div></div></form></nav><section id="main-content" class="content"><div class="example-wrap"><pre class="src-line-numbers"><span id="1">1</span> |
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| </pre><pre class="rust"><code><span class="kw">use </span><span class="kw">crate</span>::read_u8; |
| <span class="kw">use </span>error::{Error, <span class="prelude-ty">Result</span>}; |
| <span class="kw">use </span>marker::Marker; |
| <span class="kw">use </span>parser::ScanInfo; |
| <span class="kw">use </span>std::io::Read; |
| |
| <span class="kw">const </span>LUT_BITS: u8 = <span class="number">8</span>; |
| |
| <span class="attribute">#[derive(Debug)] |
| </span><span class="kw">pub struct </span>HuffmanDecoder { |
| bits: u64, |
| num_bits: u8, |
| marker: <span class="prelude-ty">Option</span><Marker>, |
| } |
| |
| <span class="kw">impl </span>HuffmanDecoder { |
| <span class="kw">pub fn </span>new() -> HuffmanDecoder { |
| HuffmanDecoder { |
| bits: <span class="number">0</span>, |
| num_bits: <span class="number">0</span>, |
| marker: <span class="prelude-val">None</span>, |
| } |
| } |
| |
| <span class="comment">// Section F.2.2.3 |
| // Figure F.16 |
| </span><span class="kw">pub fn </span>decode<R: Read>(<span class="kw-2">&mut </span><span class="self">self</span>, reader: <span class="kw-2">&mut </span>R, table: <span class="kw-2">&</span>HuffmanTable) -> <span class="prelude-ty">Result</span><u8> { |
| <span class="kw">if </span><span class="self">self</span>.num_bits < <span class="number">16 </span>{ |
| <span class="self">self</span>.read_bits(reader)<span class="question-mark">?</span>; |
| } |
| |
| <span class="kw">let </span>(value, size) = table.lut[<span class="self">self</span>.peek_bits(LUT_BITS) <span class="kw">as </span>usize]; |
| |
| <span class="kw">if </span>size > <span class="number">0 </span>{ |
| <span class="self">self</span>.consume_bits(size); |
| <span class="prelude-val">Ok</span>(value) |
| } |
| <span class="kw">else </span>{ |
| <span class="kw">let </span>bits = <span class="self">self</span>.peek_bits(<span class="number">16</span>); |
| |
| <span class="kw">for </span>i <span class="kw">in </span>LUT_BITS .. <span class="number">16 </span>{ |
| <span class="kw">let </span>code = (bits >> (<span class="number">15 </span>- i)) <span class="kw">as </span>i32; |
| |
| <span class="kw">if </span>code <= table.maxcode[i <span class="kw">as </span>usize] { |
| <span class="self">self</span>.consume_bits(i + <span class="number">1</span>); |
| |
| <span class="kw">let </span>index = (code + table.delta[i <span class="kw">as </span>usize]) <span class="kw">as </span>usize; |
| <span class="kw">return </span><span class="prelude-val">Ok</span>(table.values[index]); |
| } |
| } |
| |
| <span class="prelude-val">Err</span>(Error::Format(<span class="string">"failed to decode huffman code"</span>.to_owned())) |
| } |
| } |
| |
| <span class="kw">pub fn </span>decode_fast_ac<R: Read>(<span class="kw-2">&mut </span><span class="self">self</span>, reader: <span class="kw-2">&mut </span>R, table: <span class="kw-2">&</span>HuffmanTable) -> <span class="prelude-ty">Result</span><<span class="prelude-ty">Option</span><(i16, u8)>> { |
| <span class="kw">if let </span><span class="prelude-val">Some</span>(<span class="kw-2">ref </span>ac_lut) = table.ac_lut { |
| <span class="kw">if </span><span class="self">self</span>.num_bits < LUT_BITS { |
| <span class="self">self</span>.read_bits(reader)<span class="question-mark">?</span>; |
| } |
| |
| <span class="kw">let </span>(value, run_size) = ac_lut[<span class="self">self</span>.peek_bits(LUT_BITS) <span class="kw">as </span>usize]; |
| |
| <span class="kw">if </span>run_size != <span class="number">0 </span>{ |
| <span class="kw">let </span>run = run_size >> <span class="number">4</span>; |
| <span class="kw">let </span>size = run_size & <span class="number">0x0f</span>; |
| |
| <span class="self">self</span>.consume_bits(size); |
| <span class="kw">return </span><span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>((value, run))); |
| } |
| } |
| |
| <span class="prelude-val">Ok</span>(<span class="prelude-val">None</span>) |
| } |
| |
| <span class="attribute">#[inline] |
| </span><span class="kw">pub fn </span>get_bits<R: Read>(<span class="kw-2">&mut </span><span class="self">self</span>, reader: <span class="kw-2">&mut </span>R, count: u8) -> <span class="prelude-ty">Result</span><u16> { |
| <span class="kw">if </span><span class="self">self</span>.num_bits < count { |
| <span class="self">self</span>.read_bits(reader)<span class="question-mark">?</span>; |
| } |
| |
| <span class="kw">let </span>bits = <span class="self">self</span>.peek_bits(count); |
| <span class="self">self</span>.consume_bits(count); |
| |
| <span class="prelude-val">Ok</span>(bits) |
| } |
| |
| <span class="attribute">#[inline] |
| </span><span class="kw">pub fn </span>receive_extend<R: Read>(<span class="kw-2">&mut </span><span class="self">self</span>, reader: <span class="kw-2">&mut </span>R, count: u8) -> <span class="prelude-ty">Result</span><i16> { |
| <span class="kw">let </span>value = <span class="self">self</span>.get_bits(reader, count)<span class="question-mark">?</span>; |
| <span class="prelude-val">Ok</span>(extend(value, count)) |
| } |
| |
| <span class="kw">pub fn </span>reset(<span class="kw-2">&mut </span><span class="self">self</span>) { |
| <span class="self">self</span>.bits = <span class="number">0</span>; |
| <span class="self">self</span>.num_bits = <span class="number">0</span>; |
| } |
| |
| <span class="kw">pub fn </span>take_marker<R: Read>(<span class="kw-2">&mut </span><span class="self">self</span>, reader: <span class="kw-2">&mut </span>R) -> <span class="prelude-ty">Result</span><<span class="prelude-ty">Option</span><Marker>> { |
| <span class="self">self</span>.read_bits(reader).map(|<span class="kw">_</span>| <span class="self">self</span>.marker.take()) |
| } |
| |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>peek_bits(<span class="kw-2">&mut </span><span class="self">self</span>, count: u8) -> u16 { |
| <span class="macro">debug_assert!</span>(count <= <span class="number">16</span>); |
| <span class="macro">debug_assert!</span>(<span class="self">self</span>.num_bits >= count); |
| |
| ((<span class="self">self</span>.bits >> (<span class="number">64 </span>- count)) & ((<span class="number">1 </span><< count) - <span class="number">1</span>)) <span class="kw">as </span>u16 |
| } |
| |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>consume_bits(<span class="kw-2">&mut </span><span class="self">self</span>, count: u8) { |
| <span class="macro">debug_assert!</span>(<span class="self">self</span>.num_bits >= count); |
| |
| <span class="self">self</span>.bits <<= count <span class="kw">as </span>usize; |
| <span class="self">self</span>.num_bits -= count; |
| } |
| |
| <span class="kw">fn </span>read_bits<R: Read>(<span class="kw-2">&mut </span><span class="self">self</span>, reader: <span class="kw-2">&mut </span>R) -> <span class="prelude-ty">Result</span><()> { |
| <span class="kw">while </span><span class="self">self</span>.num_bits <= <span class="number">56 </span>{ |
| <span class="comment">// Fill with zero bits if we have reached the end. |
| </span><span class="kw">let </span>byte = <span class="kw">match </span><span class="self">self</span>.marker { |
| <span class="prelude-val">Some</span>(<span class="kw">_</span>) => <span class="number">0</span>, |
| <span class="prelude-val">None </span>=> read_u8(reader)<span class="question-mark">?</span>, |
| }; |
| |
| <span class="kw">if </span>byte == <span class="number">0xFF </span>{ |
| <span class="kw">let </span><span class="kw-2">mut </span>next_byte = read_u8(reader)<span class="question-mark">?</span>; |
| |
| <span class="comment">// Check for byte stuffing. |
| </span><span class="kw">if </span>next_byte != <span class="number">0x00 </span>{ |
| <span class="comment">// We seem to have reached the end of entropy-coded data and encountered a |
| // marker. Since we can't put data back into the reader, we have to continue |
| // reading to identify the marker so we can pass it on. |
| |
| // Section B.1.1.2 |
| // "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>next_byte == <span class="number">0xFF </span>{ |
| next_byte = read_u8(reader)<span class="question-mark">?</span>; |
| } |
| |
| <span class="kw">match </span>next_byte { |
| <span class="number">0x00 </span>=> <span class="kw">return </span><span class="prelude-val">Err</span>(Error::Format(<span class="string">"FF 00 found where marker was expected"</span>.to_owned())), |
| <span class="kw">_ </span>=> <span class="self">self</span>.marker = <span class="prelude-val">Some</span>(Marker::from_u8(next_byte).unwrap()), |
| } |
| |
| <span class="kw">continue</span>; |
| } |
| } |
| |
| <span class="self">self</span>.bits |= (byte <span class="kw">as </span>u64) << (<span class="number">56 </span>- <span class="self">self</span>.num_bits); |
| <span class="self">self</span>.num_bits += <span class="number">8</span>; |
| } |
| |
| <span class="prelude-val">Ok</span>(()) |
| } |
| } |
| |
| <span class="comment">// Section F.2.2.1 |
| // Figure F.12 |
| </span><span class="kw">fn </span>extend(value: u16, count: u8) -> i16 { |
| <span class="kw">let </span>vt = <span class="number">1 </span><< (count <span class="kw">as </span>u16 - <span class="number">1</span>); |
| |
| <span class="kw">if </span>value < vt { |
| value <span class="kw">as </span>i16 + (-<span class="number">1 </span><< count <span class="kw">as </span>i16) + <span class="number">1 |
| </span>} <span class="kw">else </span>{ |
| value <span class="kw">as </span>i16 |
| } |
| } |
| |
| <span class="attribute">#[derive(Clone, Copy, Debug, PartialEq)] |
| </span><span class="kw">pub enum </span>HuffmanTableClass { |
| DC, |
| AC, |
| } |
| |
| <span class="kw">pub struct </span>HuffmanTable { |
| values: Vec<u8>, |
| delta: [i32; <span class="number">16</span>], |
| maxcode: [i32; <span class="number">16</span>], |
| |
| lut: [(u8, u8); <span class="number">1 </span><< LUT_BITS], |
| ac_lut: <span class="prelude-ty">Option</span><[(i16, u8); <span class="number">1 </span><< LUT_BITS]>, |
| } |
| |
| <span class="kw">impl </span>HuffmanTable { |
| <span class="kw">pub fn </span>new(bits: <span class="kw-2">&</span>[u8; <span class="number">16</span>], values: <span class="kw-2">&</span>[u8], class: HuffmanTableClass) -> <span class="prelude-ty">Result</span><HuffmanTable> { |
| <span class="kw">let </span>(huffcode, huffsize) = derive_huffman_codes(bits)<span class="question-mark">?</span>; |
| |
| <span class="comment">// Section F.2.2.3 |
| // Figure F.15 |
| // delta[i] is set to VALPTR(I) - MINCODE(I) |
| </span><span class="kw">let </span><span class="kw-2">mut </span>delta = [<span class="number">0i32</span>; <span class="number">16</span>]; |
| <span class="kw">let </span><span class="kw-2">mut </span>maxcode = [-<span class="number">1i32</span>; <span class="number">16</span>]; |
| <span class="kw">let </span><span class="kw-2">mut </span>j = <span class="number">0</span>; |
| |
| <span class="kw">for </span>i <span class="kw">in </span><span class="number">0 </span>.. <span class="number">16 </span>{ |
| <span class="kw">if </span>bits[i] != <span class="number">0 </span>{ |
| delta[i] = j <span class="kw">as </span>i32 - huffcode[j] <span class="kw">as </span>i32; |
| j += bits[i] <span class="kw">as </span>usize; |
| maxcode[i] = huffcode[j - <span class="number">1</span>] <span class="kw">as </span>i32; |
| } |
| } |
| |
| <span class="comment">// Build a lookup table for faster decoding. |
| </span><span class="kw">let </span><span class="kw-2">mut </span>lut = [(<span class="number">0u8</span>, <span class="number">0u8</span>); <span class="number">1 </span><< LUT_BITS]; |
| |
| <span class="kw">for </span>(i, <span class="kw-2">&</span>size) <span class="kw">in </span>huffsize.iter().enumerate().filter(|<span class="kw-2">&</span>(<span class="kw">_</span>, <span class="kw-2">&</span>size)| size <= LUT_BITS) { |
| <span class="kw">let </span>bits_remaining = LUT_BITS - size; |
| <span class="kw">let </span>start = (huffcode[i] << bits_remaining) <span class="kw">as </span>usize; |
| |
| <span class="kw">for </span>j <span class="kw">in </span><span class="number">0 </span>.. <span class="number">1 </span><< bits_remaining { |
| lut[start + j] = (values[i], size); |
| } |
| } |
| |
| <span class="comment">// Build a lookup table for small AC coefficients which both decodes the value and does the |
| // equivalent of receive_extend. |
| </span><span class="kw">let </span>ac_lut = <span class="kw">match </span>class { |
| HuffmanTableClass::DC => <span class="prelude-val">None</span>, |
| HuffmanTableClass::AC => { |
| <span class="kw">let </span><span class="kw-2">mut </span>table = [(<span class="number">0i16</span>, <span class="number">0u8</span>); <span class="number">1 </span><< LUT_BITS]; |
| |
| <span class="kw">for </span>(i, <span class="kw-2">&</span>(value, size)) <span class="kw">in </span>lut.iter().enumerate() { |
| <span class="kw">let </span>run_length = value >> <span class="number">4</span>; |
| <span class="kw">let </span>magnitude_category = value & <span class="number">0x0f</span>; |
| |
| <span class="kw">if </span>magnitude_category > <span class="number">0 </span>&& size + magnitude_category <= LUT_BITS { |
| <span class="kw">let </span>unextended_ac_value = (((i << size) & ((<span class="number">1 </span><< LUT_BITS) - <span class="number">1</span>)) >> (LUT_BITS - magnitude_category)) <span class="kw">as </span>u16; |
| <span class="kw">let </span>ac_value = extend(unextended_ac_value, magnitude_category); |
| |
| table[i] = (ac_value, (run_length << <span class="number">4</span>) | (size + magnitude_category)); |
| } |
| } |
| |
| <span class="prelude-val">Some</span>(table) |
| }, |
| }; |
| |
| <span class="prelude-val">Ok</span>(HuffmanTable { |
| values: values.to_vec(), |
| delta: delta, |
| maxcode: maxcode, |
| lut: lut, |
| ac_lut: ac_lut, |
| }) |
| } |
| } |
| |
| <span class="comment">// Section C.2 |
| </span><span class="kw">fn </span>derive_huffman_codes(bits: <span class="kw-2">&</span>[u8; <span class="number">16</span>]) -> <span class="prelude-ty">Result</span><(Vec<u16>, Vec<u8>)> { |
| <span class="comment">// Figure C.1 |
| </span><span class="kw">let </span>huffsize = bits.iter() |
| .enumerate() |
| .fold(Vec::new(), |<span class="kw-2">mut </span>acc, (i, <span class="kw-2">&</span>value)| { |
| acc.extend(std::iter::repeat((i + <span class="number">1</span>) <span class="kw">as </span>u8).take(value <span class="kw">as </span>usize)); |
| acc |
| }); |
| |
| <span class="comment">// Figure C.2 |
| </span><span class="kw">let </span><span class="kw-2">mut </span>huffcode = <span class="macro">vec!</span>[<span class="number">0u16</span>; huffsize.len()]; |
| <span class="kw">let </span><span class="kw-2">mut </span>code_size = huffsize[<span class="number">0</span>]; |
| <span class="kw">let </span><span class="kw-2">mut </span>code = <span class="number">0u32</span>; |
| |
| <span class="kw">for </span>(i, <span class="kw-2">&</span>size) <span class="kw">in </span>huffsize.iter().enumerate() { |
| <span class="kw">while </span>code_size < size { |
| code <<= <span class="number">1</span>; |
| code_size += <span class="number">1</span>; |
| } |
| |
| <span class="kw">if </span>code >= (<span class="number">1u32 </span><< size) { |
| <span class="kw">return </span><span class="prelude-val">Err</span>(Error::Format(<span class="string">"bad huffman code length"</span>.to_owned())); |
| } |
| |
| huffcode[i] = code <span class="kw">as </span>u16; |
| code += <span class="number">1</span>; |
| } |
| |
| <span class="prelude-val">Ok</span>((huffcode, huffsize)) |
| } |
| |
| <span class="comment">// https://www.loc.gov/preservation/digital/formats/fdd/fdd000063.shtml |
| // "Avery Lee, writing in the rec.video.desktop newsgroup in 2001, commented that "MJPEG, or at |
| // least the MJPEG in AVIs having the MJPG fourcc, is restricted JPEG with a fixed -- and |
| // *omitted* -- Huffman table. The JPEG must be YCbCr colorspace, it must be 4:2:2, and it must |
| // use basic Huffman encoding, not arithmetic or progressive.... You can indeed extract the |
| // MJPEG frames and decode them with a regular JPEG decoder, but you have to prepend the DHT |
| // segment to them, or else the decoder won't have any idea how to decompress the data. |
| // The exact table necessary is given in the OpenDML spec."" |
| </span><span class="kw">pub fn </span>fill_default_mjpeg_tables(scan: <span class="kw-2">&</span>ScanInfo, |
| dc_huffman_tables: <span class="kw-2">&mut</span>[<span class="prelude-ty">Option</span><HuffmanTable>], |
| ac_huffman_tables: <span class="kw-2">&mut</span>[<span class="prelude-ty">Option</span><HuffmanTable>]) { |
| <span class="comment">// Section K.3.3 |
| |
| </span><span class="kw">if </span>dc_huffman_tables[<span class="number">0</span>].is_none() && scan.dc_table_indices.iter().any(|<span class="kw-2">&</span>i| i == <span class="number">0</span>) { |
| <span class="comment">// Table K.3 |
| </span>dc_huffman_tables[<span class="number">0</span>] = <span class="prelude-val">Some</span>(HuffmanTable::new( |
| <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>], HuffmanTableClass::DC).unwrap()); |
| } |
| <span class="kw">if </span>dc_huffman_tables[<span class="number">1</span>].is_none() && scan.dc_table_indices.iter().any(|<span class="kw-2">&</span>i| i == <span class="number">1</span>) { |
| <span class="comment">// Table K.4 |
| </span>dc_huffman_tables[<span class="number">1</span>] = <span class="prelude-val">Some</span>(HuffmanTable::new( |
| <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>], HuffmanTableClass::DC).unwrap()); |
| } |
| <span class="kw">if </span>ac_huffman_tables[<span class="number">0</span>].is_none() && scan.ac_table_indices.iter().any(|<span class="kw-2">&</span>i| i == <span class="number">0</span>) { |
| <span class="comment">// Table K.5 |
| </span>ac_huffman_tables[<span class="number">0</span>] = <span class="prelude-val">Some</span>(HuffmanTable::new( |
| <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>], HuffmanTableClass::AC).unwrap()); |
| } |
| <span class="kw">if </span>ac_huffman_tables[<span class="number">1</span>].is_none() && scan.ac_table_indices.iter().any(|<span class="kw-2">&</span>i| i == <span class="number">1</span>) { |
| <span class="comment">// Table K.6 |
| </span>ac_huffman_tables[<span class="number">1</span>] = <span class="prelude-val">Some</span>(HuffmanTable::new( |
| <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>], HuffmanTableClass::AC).unwrap()); |
| } |
| } |
| </code></pre></div> |
| </section></div></main><div id="rustdoc-vars" data-root-path="../../" data-current-crate="jpeg_decoder" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |
