| <!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/image-0.23.14/./src/codecs/jpeg/encoder.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>encoder.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="../../../../image/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="../../../../image/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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| <span id="1076">1076</span> |
| <span id="1077">1077</span> |
| <span id="1078">1078</span> |
| <span id="1079">1079</span> |
| <span id="1080">1080</span> |
| <span id="1081">1081</span> |
| <span id="1082">1082</span> |
| <span id="1083">1083</span> |
| <span id="1084">1084</span> |
| <span id="1085">1085</span> |
| <span id="1086">1086</span> |
| <span id="1087">1087</span> |
| <span id="1088">1088</span> |
| <span id="1089">1089</span> |
| <span id="1090">1090</span> |
| <span id="1091">1091</span> |
| <span id="1092">1092</span> |
| <span id="1093">1093</span> |
| <span id="1094">1094</span> |
| <span id="1095">1095</span> |
| <span id="1096">1096</span> |
| <span id="1097">1097</span> |
| <span id="1098">1098</span> |
| <span id="1099">1099</span> |
| <span id="1100">1100</span> |
| <span id="1101">1101</span> |
| </pre><pre class="rust"><code><span class="attribute">#![allow(clippy::too_many_arguments)] |
| |
| </span><span class="kw">use </span>std::convert::TryFrom; |
| <span class="kw">use </span>std::io::{<span class="self">self</span>, Write}; |
| |
| <span class="kw">use </span>num_iter::range_step; |
| |
| <span class="kw">use crate</span>::{Bgr, Bgra, ColorType, GenericImageView, ImageBuffer, Luma, LumaA, Pixel, Rgb, Rgba}; |
| <span class="kw">use </span><span class="kw">crate</span>::error::{ImageError, ImageResult, ParameterError, ParameterErrorKind, UnsupportedError, UnsupportedErrorKind}; |
| <span class="kw">use </span><span class="kw">crate</span>::image::{ImageEncoder, ImageFormat}; |
| <span class="kw">use </span><span class="kw">crate</span>::utils::clamp; |
| |
| <span class="kw">use </span><span class="kw">super</span>::entropy::build_huff_lut; |
| <span class="kw">use </span><span class="kw">super</span>::transform; |
| |
| <span class="comment">// Markers |
| // Baseline DCT |
| </span><span class="kw">static </span>SOF0: u8 = <span class="number">0xC0</span>; |
| <span class="comment">// Huffman Tables |
| </span><span class="kw">static </span>DHT: u8 = <span class="number">0xC4</span>; |
| <span class="comment">// Start of Image (standalone) |
| </span><span class="kw">static </span>SOI: u8 = <span class="number">0xD8</span>; |
| <span class="comment">// End of image (standalone) |
| </span><span class="kw">static </span>EOI: u8 = <span class="number">0xD9</span>; |
| <span class="comment">// Start of Scan |
| </span><span class="kw">static </span>SOS: u8 = <span class="number">0xDA</span>; |
| <span class="comment">// Quantization Tables |
| </span><span class="kw">static </span>DQT: u8 = <span class="number">0xDB</span>; |
| <span class="comment">// Application segments start and end |
| </span><span class="kw">static </span>APP0: u8 = <span class="number">0xE0</span>; |
| |
| <span class="comment">// section K.1 |
| // table K.1 |
| </span><span class="attribute">#[rustfmt::skip] |
| </span><span class="kw">static </span>STD_LUMA_QTABLE: [u8; <span class="number">64</span>] = [ |
| <span class="number">16</span>, <span class="number">11</span>, <span class="number">10</span>, <span class="number">16</span>, <span class="number">24</span>, <span class="number">40</span>, <span class="number">51</span>, <span class="number">61</span>, |
| <span class="number">12</span>, <span class="number">12</span>, <span class="number">14</span>, <span class="number">19</span>, <span class="number">26</span>, <span class="number">58</span>, <span class="number">60</span>, <span class="number">55</span>, |
| <span class="number">14</span>, <span class="number">13</span>, <span class="number">16</span>, <span class="number">24</span>, <span class="number">40</span>, <span class="number">57</span>, <span class="number">69</span>, <span class="number">56</span>, |
| <span class="number">14</span>, <span class="number">17</span>, <span class="number">22</span>, <span class="number">29</span>, <span class="number">51</span>, <span class="number">87</span>, <span class="number">80</span>, <span class="number">62</span>, |
| <span class="number">18</span>, <span class="number">22</span>, <span class="number">37</span>, <span class="number">56</span>, <span class="number">68</span>, <span class="number">109</span>, <span class="number">103</span>, <span class="number">77</span>, |
| <span class="number">24</span>, <span class="number">35</span>, <span class="number">55</span>, <span class="number">64</span>, <span class="number">81</span>, <span class="number">104</span>, <span class="number">113</span>, <span class="number">92</span>, |
| <span class="number">49</span>, <span class="number">64</span>, <span class="number">78</span>, <span class="number">87</span>, <span class="number">103</span>, <span class="number">121</span>, <span class="number">120</span>, <span class="number">101</span>, |
| <span class="number">72</span>, <span class="number">92</span>, <span class="number">95</span>, <span class="number">98</span>, <span class="number">112</span>, <span class="number">100</span>, <span class="number">103</span>, <span class="number">99</span>, |
| ]; |
| |
| <span class="comment">// table K.2 |
| </span><span class="attribute">#[rustfmt::skip] |
| </span><span class="kw">static </span>STD_CHROMA_QTABLE: [u8; <span class="number">64</span>] = [ |
| <span class="number">17</span>, <span class="number">18</span>, <span class="number">24</span>, <span class="number">47</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, |
| <span class="number">18</span>, <span class="number">21</span>, <span class="number">26</span>, <span class="number">66</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, |
| <span class="number">24</span>, <span class="number">26</span>, <span class="number">56</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, |
| <span class="number">47</span>, <span class="number">66</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, |
| <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, |
| <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, |
| <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, |
| <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, <span class="number">99</span>, |
| ]; |
| |
| <span class="comment">// section K.3 |
| // Code lengths and values for table K.3 |
| </span><span class="kw">static </span>STD_LUMA_DC_CODE_LENGTHS: [u8; <span class="number">16</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">static </span>STD_LUMA_DC_VALUES: [u8; <span class="number">12</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="comment">// Code lengths and values for table K.4 |
| </span><span class="kw">static </span>STD_CHROMA_DC_CODE_LENGTHS: [u8; <span class="number">16</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">static </span>STD_CHROMA_DC_VALUES: [u8; <span class="number">12</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="comment">// Code lengths and values for table k.5 |
| </span><span class="kw">static </span>STD_LUMA_AC_CODE_LENGTHS: [u8; <span class="number">16</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">static </span>STD_LUMA_AC_VALUES: [u8; <span class="number">162</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="comment">// Code lengths and values for table k.6 |
| </span><span class="kw">static </span>STD_CHROMA_AC_CODE_LENGTHS: [u8; <span class="number">16</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">static </span>STD_CHROMA_AC_VALUES: [u8; <span class="number">162</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="kw">static </span>DCCLASS: u8 = <span class="number">0</span>; |
| <span class="kw">static </span>ACCLASS: u8 = <span class="number">1</span>; |
| |
| <span class="kw">static </span>LUMADESTINATION: u8 = <span class="number">0</span>; |
| <span class="kw">static </span>CHROMADESTINATION: u8 = <span class="number">1</span>; |
| |
| <span class="kw">static </span>LUMAID: u8 = <span class="number">1</span>; |
| <span class="kw">static </span>CHROMABLUEID: u8 = <span class="number">2</span>; |
| <span class="kw">static </span>CHROMAREDID: u8 = <span class="number">3</span>; |
| |
| <span class="doccomment">/// The permutation of dct coefficients. |
| </span><span class="attribute">#[rustfmt::skip] |
| </span><span class="kw">static </span>UNZIGZAG: [u8; <span class="number">64</span>] = [ |
| <span class="number">0</span>, <span class="number">1</span>, <span class="number">8</span>, <span class="number">16</span>, <span class="number">9</span>, <span class="number">2</span>, <span class="number">3</span>, <span class="number">10</span>, |
| <span class="number">17</span>, <span class="number">24</span>, <span class="number">32</span>, <span class="number">25</span>, <span class="number">18</span>, <span class="number">11</span>, <span class="number">4</span>, <span class="number">5</span>, |
| <span class="number">12</span>, <span class="number">19</span>, <span class="number">26</span>, <span class="number">33</span>, <span class="number">40</span>, <span class="number">48</span>, <span class="number">41</span>, <span class="number">34</span>, |
| <span class="number">27</span>, <span class="number">20</span>, <span class="number">13</span>, <span class="number">6</span>, <span class="number">7</span>, <span class="number">14</span>, <span class="number">21</span>, <span class="number">28</span>, |
| <span class="number">35</span>, <span class="number">42</span>, <span class="number">49</span>, <span class="number">56</span>, <span class="number">57</span>, <span class="number">50</span>, <span class="number">43</span>, <span class="number">36</span>, |
| <span class="number">29</span>, <span class="number">22</span>, <span class="number">15</span>, <span class="number">23</span>, <span class="number">30</span>, <span class="number">37</span>, <span class="number">44</span>, <span class="number">51</span>, |
| <span class="number">58</span>, <span class="number">59</span>, <span class="number">52</span>, <span class="number">45</span>, <span class="number">38</span>, <span class="number">31</span>, <span class="number">39</span>, <span class="number">46</span>, |
| <span class="number">53</span>, <span class="number">60</span>, <span class="number">61</span>, <span class="number">54</span>, <span class="number">47</span>, <span class="number">55</span>, <span class="number">62</span>, <span class="number">63</span>, |
| ]; |
| |
| <span class="doccomment">/// A representation of a JPEG component |
| </span><span class="attribute">#[derive(Copy, Clone)] |
| </span><span class="kw">struct </span>Component { |
| <span class="doccomment">/// The Component's identifier |
| </span>id: u8, |
| |
| <span class="doccomment">/// Horizontal sampling factor |
| </span>h: u8, |
| |
| <span class="doccomment">/// Vertical sampling factor |
| </span>v: u8, |
| |
| <span class="doccomment">/// The quantization table selector |
| </span>tq: u8, |
| |
| <span class="doccomment">/// Index to the Huffman DC Table |
| </span>dc_table: u8, |
| |
| <span class="doccomment">/// Index to the AC Huffman Table |
| </span>ac_table: u8, |
| |
| <span class="doccomment">/// The dc prediction of the component |
| </span>_dc_pred: i32, |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">struct </span>BitWriter<<span class="lifetime">'a</span>, W: <span class="lifetime">'a</span>> { |
| w: <span class="kw-2">&</span><span class="lifetime">'a </span><span class="kw-2">mut </span>W, |
| accumulator: u32, |
| nbits: u8, |
| } |
| |
| <span class="kw">impl</span><<span class="lifetime">'a</span>, W: Write + <span class="lifetime">'a</span>> BitWriter<<span class="lifetime">'a</span>, W> { |
| <span class="kw">fn </span>new(w: <span class="kw-2">&</span><span class="lifetime">'a </span><span class="kw-2">mut </span>W) -> <span class="self">Self </span>{ |
| BitWriter { |
| w, |
| accumulator: <span class="number">0</span>, |
| nbits: <span class="number">0</span>, |
| } |
| } |
| |
| <span class="kw">fn </span>write_bits(<span class="kw-2">&mut </span><span class="self">self</span>, bits: u16, size: u8) -> io::Result<()> { |
| <span class="kw">if </span>size == <span class="number">0 </span>{ |
| <span class="kw">return </span><span class="prelude-val">Ok</span>(()); |
| } |
| |
| <span class="self">self</span>.nbits += size; |
| <span class="self">self</span>.accumulator |= u32::from(bits) << (<span class="number">32 </span>- <span class="self">self</span>.nbits) <span class="kw">as </span>usize; |
| |
| <span class="kw">while </span><span class="self">self</span>.nbits >= <span class="number">8 </span>{ |
| <span class="kw">let </span>byte = <span class="self">self</span>.accumulator >> <span class="number">24</span>; |
| <span class="self">self</span>.w.write_all(<span class="kw-2">&</span>[byte <span class="kw">as </span>u8])<span class="question-mark">?</span>; |
| |
| <span class="kw">if </span>byte == <span class="number">0xFF </span>{ |
| <span class="self">self</span>.w.write_all(<span class="kw-2">&</span>[<span class="number">0x00</span>])<span class="question-mark">?</span>; |
| } |
| |
| <span class="self">self</span>.nbits -= <span class="number">8</span>; |
| <span class="self">self</span>.accumulator <<= <span class="number">8</span>; |
| } |
| |
| <span class="prelude-val">Ok</span>(()) |
| } |
| |
| <span class="kw">fn </span>pad_byte(<span class="kw-2">&mut </span><span class="self">self</span>) -> io::Result<()> { |
| <span class="self">self</span>.write_bits(<span class="number">0x7F</span>, <span class="number">7</span>) |
| } |
| |
| <span class="kw">fn </span>huffman_encode(<span class="kw-2">&mut </span><span class="self">self</span>, val: u8, table: <span class="kw-2">&</span>[(u8, u16); <span class="number">256</span>]) -> io::Result<()> { |
| <span class="kw">let </span>(size, code) = table[val <span class="kw">as </span>usize]; |
| |
| <span class="kw">if </span>size > <span class="number">16 </span>{ |
| <span class="macro">panic!</span>(<span class="string">"bad huffman value"</span>); |
| } |
| |
| <span class="self">self</span>.write_bits(code, size) |
| } |
| |
| <span class="kw">fn </span>write_block( |
| <span class="kw-2">&mut </span><span class="self">self</span>, |
| block: <span class="kw-2">&</span>[i32; <span class="number">64</span>], |
| prevdc: i32, |
| dctable: <span class="kw-2">&</span>[(u8, u16); <span class="number">256</span>], |
| actable: <span class="kw-2">&</span>[(u8, u16); <span class="number">256</span>], |
| ) -> io::Result<i32> { |
| <span class="comment">// Differential DC encoding |
| </span><span class="kw">let </span>dcval = block[<span class="number">0</span>]; |
| <span class="kw">let </span>diff = dcval - prevdc; |
| <span class="kw">let </span>(size, value) = encode_coefficient(diff); |
| |
| <span class="self">self</span>.huffman_encode(size, dctable)<span class="question-mark">?</span>; |
| <span class="self">self</span>.write_bits(value, size)<span class="question-mark">?</span>; |
| |
| <span class="comment">// Figure F.2 |
| </span><span class="kw">let </span><span class="kw-2">mut </span>zero_run = <span class="number">0</span>; |
| |
| <span class="kw">for </span><span class="kw-2">&</span>k <span class="kw">in </span><span class="kw-2">&</span>UNZIGZAG[<span class="number">1</span>..] { |
| <span class="kw">if </span>block[k <span class="kw">as </span>usize] == <span class="number">0 </span>{ |
| zero_run += <span class="number">1</span>; |
| } <span class="kw">else </span>{ |
| <span class="kw">while </span>zero_run > <span class="number">15 </span>{ |
| <span class="self">self</span>.huffman_encode(<span class="number">0xF0</span>, actable)<span class="question-mark">?</span>; |
| zero_run -= <span class="number">16</span>; |
| } |
| |
| <span class="kw">let </span>(size, value) = encode_coefficient(block[k <span class="kw">as </span>usize]); |
| <span class="kw">let </span>symbol = (zero_run << <span class="number">4</span>) | size; |
| |
| <span class="self">self</span>.huffman_encode(symbol, actable)<span class="question-mark">?</span>; |
| <span class="self">self</span>.write_bits(value, size)<span class="question-mark">?</span>; |
| |
| zero_run = <span class="number">0</span>; |
| } |
| } |
| |
| <span class="kw">if </span>block[UNZIGZAG[<span class="number">63</span>] <span class="kw">as </span>usize] == <span class="number">0 </span>{ |
| <span class="self">self</span>.huffman_encode(<span class="number">0x00</span>, actable)<span class="question-mark">?</span>; |
| } |
| |
| <span class="prelude-val">Ok</span>(dcval) |
| } |
| |
| <span class="kw">fn </span>write_marker(<span class="kw-2">&mut </span><span class="self">self</span>, marker: u8) -> io::Result<()> { |
| <span class="self">self</span>.w.write_all(<span class="kw-2">&</span>[<span class="number">0xFF</span>, marker]) |
| } |
| |
| <span class="kw">fn </span>write_segment(<span class="kw-2">&mut </span><span class="self">self</span>, marker: u8, data: <span class="kw-2">&</span>[u8]) -> io::Result<()> { |
| <span class="self">self</span>.w.write_all(<span class="kw-2">&</span>[<span class="number">0xFF</span>, marker])<span class="question-mark">?</span>; |
| <span class="self">self</span>.w.write_all(<span class="kw-2">&</span>(data.len() <span class="kw">as </span>u16 + <span class="number">2</span>).to_be_bytes())<span class="question-mark">?</span>; |
| <span class="self">self</span>.w.write_all(data) |
| } |
| } |
| |
| <span class="doccomment">/// Represents a unit in which the density of an image is measured |
| </span><span class="attribute">#[derive(Clone, Copy, Debug, Eq, PartialEq)] |
| </span><span class="kw">pub enum </span>PixelDensityUnit { |
| <span class="doccomment">/// Represents the absence of a unit, the values indicate only a |
| /// [pixel aspect ratio](https://en.wikipedia.org/wiki/Pixel_aspect_ratio) |
| </span>PixelAspectRatio, |
| |
| <span class="doccomment">/// Pixels per inch (2.54 cm) |
| </span>Inches, |
| |
| <span class="doccomment">/// Pixels per centimeter |
| </span>Centimeters, |
| } |
| |
| <span class="doccomment">/// Represents the pixel density of an image |
| /// |
| /// For example, a 300 DPI image is represented by: |
| /// |
| /// ```rust |
| /// use image::jpeg::*; |
| /// let hdpi = PixelDensity::dpi(300); |
| /// assert_eq!(hdpi, PixelDensity {density: (300,300), unit: PixelDensityUnit::Inches}) |
| /// ``` |
| </span><span class="attribute">#[derive(Clone, Copy, Debug, Eq, PartialEq)] |
| </span><span class="kw">pub struct </span>PixelDensity { |
| <span class="doccomment">/// A couple of values for (Xdensity, Ydensity) |
| </span><span class="kw">pub </span>density: (u16, u16), |
| <span class="doccomment">/// The unit in which the density is measured |
| </span><span class="kw">pub </span>unit: PixelDensityUnit, |
| } |
| |
| <span class="kw">impl </span>PixelDensity { |
| <span class="doccomment">/// Creates the most common pixel density type: |
| /// the horizontal and the vertical density are equal, |
| /// and measured in pixels per inch. |
| </span><span class="kw">pub fn </span>dpi(density: u16) -> <span class="self">Self </span>{ |
| PixelDensity { |
| density: (density, density), |
| unit: PixelDensityUnit::Inches, |
| } |
| } |
| } |
| |
| <span class="kw">impl </span>Default <span class="kw">for </span>PixelDensity { |
| <span class="doccomment">/// Returns a pixel density with a pixel aspect ratio of 1 |
| </span><span class="kw">fn </span>default() -> <span class="self">Self </span>{ |
| PixelDensity { |
| density: (<span class="number">1</span>, <span class="number">1</span>), |
| unit: PixelDensityUnit::PixelAspectRatio, |
| } |
| } |
| } |
| |
| <span class="doccomment">/// The representation of a JPEG encoder |
| </span><span class="kw">pub struct </span>JpegEncoder<<span class="lifetime">'a</span>, W: <span class="lifetime">'a</span>> { |
| writer: BitWriter<<span class="lifetime">'a</span>, W>, |
| |
| components: Vec<Component>, |
| tables: Vec<[u8; <span class="number">64</span>]>, |
| |
| luma_dctable: Box<[(u8, u16); <span class="number">256</span>]>, |
| luma_actable: Box<[(u8, u16); <span class="number">256</span>]>, |
| chroma_dctable: Box<[(u8, u16); <span class="number">256</span>]>, |
| chroma_actable: Box<[(u8, u16); <span class="number">256</span>]>, |
| |
| pixel_density: PixelDensity, |
| } |
| |
| <span class="doccomment">/// JPEG Encoder |
| /// |
| /// An alias of [`JpegEncoder`]. |
| /// |
| /// TODO: remove |
| /// |
| /// [`JpegEncoder`]: struct.JpegEncoder.html |
| </span><span class="attribute">#[allow(dead_code)] |
| #[deprecated(note = <span class="string">"Use `JpegEncoder` instead"</span>)] |
| </span><span class="kw">pub type </span>JPEGEncoder<<span class="lifetime">'a</span>, W> = JpegEncoder<<span class="lifetime">'a</span>, W>; |
| |
| <span class="kw">impl</span><<span class="lifetime">'a</span>, W: Write> JpegEncoder<<span class="lifetime">'a</span>, W> { |
| <span class="doccomment">/// Create a new encoder that writes its output to ```w``` |
| </span><span class="kw">pub fn </span>new(w: <span class="kw-2">&mut </span>W) -> JpegEncoder<W> { |
| JpegEncoder::new_with_quality(w, <span class="number">75</span>) |
| } |
| |
| <span class="doccomment">/// Create a new encoder that writes its output to ```w```, and has |
| /// the quality parameter ```quality``` with a value in the range 1-100 |
| /// where 1 is the worst and 100 is the best. |
| </span><span class="kw">pub fn </span>new_with_quality(w: <span class="kw-2">&mut </span>W, quality: u8) -> JpegEncoder<W> { |
| <span class="kw">let </span>ld = Box::new(build_huff_lut(<span class="kw-2">&</span>STD_LUMA_DC_CODE_LENGTHS, <span class="kw-2">&</span>STD_LUMA_DC_VALUES)); |
| <span class="kw">let </span>la = Box::new(build_huff_lut(<span class="kw-2">&</span>STD_LUMA_AC_CODE_LENGTHS, <span class="kw-2">&</span>STD_LUMA_AC_VALUES)); |
| |
| <span class="kw">let </span>cd = Box::new(build_huff_lut(<span class="kw-2">&</span>STD_CHROMA_DC_CODE_LENGTHS, <span class="kw-2">&</span>STD_CHROMA_DC_VALUES)); |
| <span class="kw">let </span>ca = Box::new(build_huff_lut(<span class="kw-2">&</span>STD_CHROMA_AC_CODE_LENGTHS, <span class="kw-2">&</span>STD_CHROMA_AC_VALUES)); |
| |
| <span class="kw">let </span>components = <span class="macro">vec!</span>[ |
| Component { |
| id: LUMAID, |
| h: <span class="number">1</span>, |
| v: <span class="number">1</span>, |
| tq: LUMADESTINATION, |
| dc_table: LUMADESTINATION, |
| ac_table: LUMADESTINATION, |
| _dc_pred: <span class="number">0</span>, |
| }, |
| Component { |
| id: CHROMABLUEID, |
| h: <span class="number">1</span>, |
| v: <span class="number">1</span>, |
| tq: CHROMADESTINATION, |
| dc_table: CHROMADESTINATION, |
| ac_table: CHROMADESTINATION, |
| _dc_pred: <span class="number">0</span>, |
| }, |
| Component { |
| id: CHROMAREDID, |
| h: <span class="number">1</span>, |
| v: <span class="number">1</span>, |
| tq: CHROMADESTINATION, |
| dc_table: CHROMADESTINATION, |
| ac_table: CHROMADESTINATION, |
| _dc_pred: <span class="number">0</span>, |
| }, |
| ]; |
| |
| <span class="comment">// Derive our quantization table scaling value using the libjpeg algorithm |
| </span><span class="kw">let </span>scale = u32::from(clamp(quality, <span class="number">1</span>, <span class="number">100</span>)); |
| <span class="kw">let </span>scale = <span class="kw">if </span>scale < <span class="number">50 </span>{ |
| <span class="number">5000 </span>/ scale |
| } <span class="kw">else </span>{ |
| <span class="number">200 </span>- scale * <span class="number">2 |
| </span>}; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>tables = <span class="macro">vec!</span>[STD_LUMA_QTABLE, STD_CHROMA_QTABLE]; |
| tables.iter_mut().for_each(|t| |
| t.iter_mut().for_each(|v| { |
| <span class="kw-2">*</span>v = clamp( |
| (u32::from(<span class="kw-2">*</span>v) * scale + <span class="number">50</span>) / <span class="number">100</span>, |
| <span class="number">1</span>, u32::from(u8::max_value())) <span class="kw">as </span>u8; |
| }) |
| ); |
| |
| JpegEncoder { |
| writer: BitWriter::new(w), |
| |
| components, |
| tables, |
| |
| luma_dctable: ld, |
| luma_actable: la, |
| chroma_dctable: cd, |
| chroma_actable: ca, |
| |
| pixel_density: PixelDensity::default(), |
| } |
| } |
| |
| <span class="doccomment">/// Set the pixel density of the images the encoder will encode. |
| /// If this method is not called, then a default pixel aspect ratio of 1x1 will be applied, |
| /// and no DPI information will be stored in the image. |
| </span><span class="kw">pub fn </span>set_pixel_density(<span class="kw-2">&mut </span><span class="self">self</span>, pixel_density: PixelDensity) { |
| <span class="self">self</span>.pixel_density = pixel_density; |
| } |
| |
| <span class="doccomment">/// Encodes the image stored in the raw byte buffer ```image``` |
| /// that has dimensions ```width``` and ```height``` |
| /// and ```ColorType``` ```c``` |
| /// |
| /// The Image in encoded with subsampling ratio 4:2:2 |
| </span><span class="kw">pub fn </span>encode( |
| <span class="kw-2">&mut </span><span class="self">self</span>, |
| image: <span class="kw-2">&</span>[u8], |
| width: u32, |
| height: u32, |
| color_type: ColorType, |
| ) -> ImageResult<()> { |
| <span class="kw">match </span>color_type { |
| ColorType::L8 => { |
| <span class="kw">let </span>image: ImageBuffer<Luma<<span class="kw">_</span>>, <span class="kw">_</span>> = ImageBuffer::from_raw(width, height, image).unwrap(); |
| <span class="self">self</span>.encode_image(<span class="kw-2">&</span>image) |
| }, |
| ColorType::La8 => { |
| <span class="kw">let </span>image: ImageBuffer<LumaA<<span class="kw">_</span>>, <span class="kw">_</span>> = ImageBuffer::from_raw(width, height, image).unwrap(); |
| <span class="self">self</span>.encode_image(<span class="kw-2">&</span>image) |
| }, |
| ColorType::Rgb8 => { |
| <span class="kw">let </span>image: ImageBuffer<Rgb<<span class="kw">_</span>>, <span class="kw">_</span>> = ImageBuffer::from_raw(width, height, image).unwrap(); |
| <span class="self">self</span>.encode_image(<span class="kw-2">&</span>image) |
| }, |
| ColorType::Rgba8 => { |
| <span class="kw">let </span>image: ImageBuffer<Rgba<<span class="kw">_</span>>, <span class="kw">_</span>> = ImageBuffer::from_raw(width, height, image).unwrap(); |
| <span class="self">self</span>.encode_image(<span class="kw-2">&</span>image) |
| }, |
| ColorType::Bgr8 => { |
| <span class="kw">let </span>image: ImageBuffer<Bgr<<span class="kw">_</span>>, <span class="kw">_</span>> = ImageBuffer::from_raw(width, height, image).unwrap(); |
| <span class="self">self</span>.encode_image(<span class="kw-2">&</span>image) |
| }, |
| ColorType::Bgra8 => { |
| <span class="kw">let </span>image: ImageBuffer<Bgra<<span class="kw">_</span>>, <span class="kw">_</span>> = ImageBuffer::from_raw(width, height, image).unwrap(); |
| <span class="self">self</span>.encode_image(<span class="kw-2">&</span>image) |
| }, |
| <span class="kw">_ </span>=> { |
| <span class="prelude-val">Err</span>(ImageError::Unsupported( |
| UnsupportedError::from_format_and_kind( |
| ImageFormat::Jpeg.into(), |
| UnsupportedErrorKind::Color(color_type.into()), |
| ), |
| )) |
| }, |
| } |
| } |
| |
| <span class="doccomment">/// Encodes the given image. |
| /// |
| /// As a special feature this does not require the whole image to be present in memory at the |
| /// same time such that it may be computed on the fly, which is why this method exists on this |
| /// encoder but not on others. Instead the encoder will iterate over 8-by-8 blocks of pixels at |
| /// a time, inspecting each pixel exactly once. You can rely on this behaviour when calling |
| /// this method. |
| /// |
| /// The Image in encoded with subsampling ratio 4:2:2 |
| </span><span class="kw">pub fn </span>encode_image<I: GenericImageView>( |
| <span class="kw-2">&mut </span><span class="self">self</span>, |
| image: <span class="kw-2">&</span>I, |
| ) -> ImageResult<()> { |
| <span class="kw">let </span>n = I::Pixel::CHANNEL_COUNT; |
| <span class="kw">let </span>num_components = <span class="kw">if </span>n == <span class="number">1 </span>|| n == <span class="number">2 </span>{ <span class="number">1 </span>} <span class="kw">else </span>{ <span class="number">3 </span>}; |
| |
| <span class="self">self</span>.writer.write_marker(SOI)<span class="question-mark">?</span>; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>buf = Vec::new(); |
| |
| build_jfif_header(<span class="kw-2">&mut </span>buf, <span class="self">self</span>.pixel_density); |
| <span class="self">self</span>.writer.write_segment(APP0, <span class="kw-2">&</span>buf)<span class="question-mark">?</span>; |
| |
| build_frame_header( |
| <span class="kw-2">&mut </span>buf, |
| <span class="number">8</span>, |
| <span class="comment">// TODO: not idiomatic yet. Should be an EncodingError and mention jpg. Further it |
| // should check dimensions prior to writing. |
| </span>u16::try_from(image.width()).map_err(|<span class="kw">_</span>| { |
| ImageError::Parameter(ParameterError::from_kind( |
| ParameterErrorKind::DimensionMismatch, |
| )) |
| })<span class="question-mark">?</span>, |
| u16::try_from(image.height()).map_err(|<span class="kw">_</span>| { |
| ImageError::Parameter(ParameterError::from_kind( |
| ParameterErrorKind::DimensionMismatch, |
| )) |
| })<span class="question-mark">?</span>, |
| <span class="kw-2">&</span><span class="self">self</span>.components[..num_components], |
| ); |
| <span class="self">self</span>.writer.write_segment(SOF0, <span class="kw-2">&</span>buf)<span class="question-mark">?</span>; |
| |
| <span class="macro">assert_eq!</span>(<span class="self">self</span>.tables.len(), <span class="number">2</span>); |
| <span class="kw">let </span>numtables = <span class="kw">if </span>num_components == <span class="number">1 </span>{ <span class="number">1 </span>} <span class="kw">else </span>{ <span class="number">2 </span>}; |
| |
| <span class="kw">for </span>(i, table) <span class="kw">in </span><span class="self">self</span>.tables[..numtables].iter().enumerate() { |
| build_quantization_segment(<span class="kw-2">&mut </span>buf, <span class="number">8</span>, i <span class="kw">as </span>u8, table); |
| <span class="self">self</span>.writer.write_segment(DQT, <span class="kw-2">&</span>buf)<span class="question-mark">?</span>; |
| } |
| |
| build_huffman_segment( |
| <span class="kw-2">&mut </span>buf, |
| DCCLASS, |
| LUMADESTINATION, |
| <span class="kw-2">&</span>STD_LUMA_DC_CODE_LENGTHS, |
| <span class="kw-2">&</span>STD_LUMA_DC_VALUES, |
| ); |
| <span class="self">self</span>.writer.write_segment(DHT, <span class="kw-2">&</span>buf)<span class="question-mark">?</span>; |
| |
| build_huffman_segment( |
| <span class="kw-2">&mut </span>buf, |
| ACCLASS, |
| LUMADESTINATION, |
| <span class="kw-2">&</span>STD_LUMA_AC_CODE_LENGTHS, |
| <span class="kw-2">&</span>STD_LUMA_AC_VALUES, |
| ); |
| <span class="self">self</span>.writer.write_segment(DHT, <span class="kw-2">&</span>buf)<span class="question-mark">?</span>; |
| |
| <span class="kw">if </span>num_components == <span class="number">3 </span>{ |
| build_huffman_segment( |
| <span class="kw-2">&mut </span>buf, |
| DCCLASS, |
| CHROMADESTINATION, |
| <span class="kw-2">&</span>STD_CHROMA_DC_CODE_LENGTHS, |
| <span class="kw-2">&</span>STD_CHROMA_DC_VALUES, |
| ); |
| <span class="self">self</span>.writer.write_segment(DHT, <span class="kw-2">&</span>buf)<span class="question-mark">?</span>; |
| |
| build_huffman_segment( |
| <span class="kw-2">&mut </span>buf, |
| ACCLASS, |
| CHROMADESTINATION, |
| <span class="kw-2">&</span>STD_CHROMA_AC_CODE_LENGTHS, |
| <span class="kw-2">&</span>STD_CHROMA_AC_VALUES, |
| ); |
| <span class="self">self</span>.writer.write_segment(DHT, <span class="kw-2">&</span>buf)<span class="question-mark">?</span>; |
| } |
| |
| build_scan_header(<span class="kw-2">&mut </span>buf, <span class="kw-2">&</span><span class="self">self</span>.components[..num_components]); |
| <span class="self">self</span>.writer.write_segment(SOS, <span class="kw-2">&</span>buf)<span class="question-mark">?</span>; |
| |
| |
| <span class="kw">if </span>I::Pixel::COLOR_TYPE.has_color() { |
| <span class="self">self</span>.encode_rgb(image) |
| } <span class="kw">else </span>{ |
| <span class="self">self</span>.encode_gray(image) |
| }<span class="question-mark">?</span>; |
| |
| <span class="self">self</span>.writer.pad_byte()<span class="question-mark">?</span>; |
| <span class="self">self</span>.writer.write_marker(EOI)<span class="question-mark">?</span>; |
| <span class="prelude-val">Ok</span>(()) |
| } |
| |
| <span class="kw">fn </span>encode_gray<I: GenericImageView>( |
| <span class="kw-2">&mut </span><span class="self">self</span>, |
| image: <span class="kw-2">&</span>I, |
| ) -> io::Result<()> { |
| <span class="kw">let </span><span class="kw-2">mut </span>yblock = [<span class="number">0u8</span>; <span class="number">64</span>]; |
| <span class="kw">let </span><span class="kw-2">mut </span>y_dcprev = <span class="number">0</span>; |
| <span class="kw">let </span><span class="kw-2">mut </span>dct_yblock = [<span class="number">0i32</span>; <span class="number">64</span>]; |
| |
| <span class="kw">for </span>y <span class="kw">in </span>range_step(<span class="number">0</span>, image.height(), <span class="number">8</span>) { |
| <span class="kw">for </span>x <span class="kw">in </span>range_step(<span class="number">0</span>, image.width(), <span class="number">8</span>) { |
| copy_blocks_gray(image, x, y, <span class="kw-2">&mut </span>yblock); |
| |
| <span class="comment">// Level shift and fdct |
| // Coeffs are scaled by 8 |
| </span>transform::fdct(<span class="kw-2">&</span>yblock, <span class="kw-2">&mut </span>dct_yblock); |
| |
| <span class="comment">// Quantization |
| </span><span class="kw">for </span>(i, dct) <span class="kw">in </span>dct_yblock.iter_mut().enumerate() { |
| <span class="kw-2">*</span>dct = ((<span class="kw-2">*</span>dct / <span class="number">8</span>) <span class="kw">as </span>f32 / f32::from(<span class="self">self</span>.tables[<span class="number">0</span>][i])).round() <span class="kw">as </span>i32; |
| } |
| |
| <span class="kw">let </span>la = <span class="kw-2">&*</span><span class="self">self</span>.luma_actable; |
| <span class="kw">let </span>ld = <span class="kw-2">&*</span><span class="self">self</span>.luma_dctable; |
| |
| y_dcprev = <span class="self">self</span>.writer.write_block(<span class="kw-2">&</span>dct_yblock, y_dcprev, ld, la)<span class="question-mark">?</span>; |
| } |
| } |
| |
| <span class="prelude-val">Ok</span>(()) |
| } |
| |
| <span class="kw">fn </span>encode_rgb<I: GenericImageView>( |
| <span class="kw-2">&mut </span><span class="self">self</span>, |
| image: <span class="kw-2">&</span>I, |
| ) -> io::Result<()> { |
| <span class="kw">let </span><span class="kw-2">mut </span>y_dcprev = <span class="number">0</span>; |
| <span class="kw">let </span><span class="kw-2">mut </span>cb_dcprev = <span class="number">0</span>; |
| <span class="kw">let </span><span class="kw-2">mut </span>cr_dcprev = <span class="number">0</span>; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>dct_yblock = [<span class="number">0i32</span>; <span class="number">64</span>]; |
| <span class="kw">let </span><span class="kw-2">mut </span>dct_cb_block = [<span class="number">0i32</span>; <span class="number">64</span>]; |
| <span class="kw">let </span><span class="kw-2">mut </span>dct_cr_block = [<span class="number">0i32</span>; <span class="number">64</span>]; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>yblock = [<span class="number">0u8</span>; <span class="number">64</span>]; |
| <span class="kw">let </span><span class="kw-2">mut </span>cb_block = [<span class="number">0u8</span>; <span class="number">64</span>]; |
| <span class="kw">let </span><span class="kw-2">mut </span>cr_block = [<span class="number">0u8</span>; <span class="number">64</span>]; |
| |
| <span class="kw">for </span>y <span class="kw">in </span>range_step(<span class="number">0</span>, image.height(), <span class="number">8</span>) { |
| <span class="kw">for </span>x <span class="kw">in </span>range_step(<span class="number">0</span>, image.width(), <span class="number">8</span>) { |
| <span class="comment">// RGB -> YCbCr |
| </span>copy_blocks_ycbcr( |
| image, |
| x, |
| y, |
| <span class="kw-2">&mut </span>yblock, |
| <span class="kw-2">&mut </span>cb_block, |
| <span class="kw-2">&mut </span>cr_block, |
| ); |
| |
| <span class="comment">// Level shift and fdct |
| // Coeffs are scaled by 8 |
| </span>transform::fdct(<span class="kw-2">&</span>yblock, <span class="kw-2">&mut </span>dct_yblock); |
| transform::fdct(<span class="kw-2">&</span>cb_block, <span class="kw-2">&mut </span>dct_cb_block); |
| transform::fdct(<span class="kw-2">&</span>cr_block, <span class="kw-2">&mut </span>dct_cr_block); |
| |
| <span class="comment">// Quantization |
| </span><span class="kw">for </span>i <span class="kw">in </span><span class="number">0usize</span>..<span class="number">64 </span>{ |
| dct_yblock[i] = |
| ((dct_yblock[i] / <span class="number">8</span>) <span class="kw">as </span>f32 / f32::from(<span class="self">self</span>.tables[<span class="number">0</span>][i])).round() <span class="kw">as </span>i32; |
| dct_cb_block[i] = ((dct_cb_block[i] / <span class="number">8</span>) <span class="kw">as </span>f32 |
| / f32::from(<span class="self">self</span>.tables[<span class="number">1</span>][i])) |
| .round() <span class="kw">as </span>i32; |
| dct_cr_block[i] = ((dct_cr_block[i] / <span class="number">8</span>) <span class="kw">as </span>f32 |
| / f32::from(<span class="self">self</span>.tables[<span class="number">1</span>][i])) |
| .round() <span class="kw">as </span>i32; |
| } |
| |
| <span class="kw">let </span>la = <span class="kw-2">&*</span><span class="self">self</span>.luma_actable; |
| <span class="kw">let </span>ld = <span class="kw-2">&*</span><span class="self">self</span>.luma_dctable; |
| <span class="kw">let </span>cd = <span class="kw-2">&*</span><span class="self">self</span>.chroma_dctable; |
| <span class="kw">let </span>ca = <span class="kw-2">&*</span><span class="self">self</span>.chroma_actable; |
| |
| y_dcprev = <span class="self">self</span>.writer.write_block(<span class="kw-2">&</span>dct_yblock, y_dcprev, ld, la)<span class="question-mark">?</span>; |
| cb_dcprev = <span class="self">self</span>.writer.write_block(<span class="kw-2">&</span>dct_cb_block, cb_dcprev, cd, ca)<span class="question-mark">?</span>; |
| cr_dcprev = <span class="self">self</span>.writer.write_block(<span class="kw-2">&</span>dct_cr_block, cr_dcprev, cd, ca)<span class="question-mark">?</span>; |
| } |
| } |
| |
| <span class="prelude-val">Ok</span>(()) |
| } |
| } |
| |
| <span class="kw">impl</span><<span class="lifetime">'a</span>, W: Write> ImageEncoder <span class="kw">for </span>JpegEncoder<<span class="lifetime">'a</span>, W> { |
| <span class="kw">fn </span>write_image( |
| <span class="kw-2">mut </span><span class="self">self</span>, |
| buf: <span class="kw-2">&</span>[u8], |
| width: u32, |
| height: u32, |
| color_type: ColorType, |
| ) -> ImageResult<()> { |
| <span class="self">self</span>.encode(buf, width, height, color_type) |
| } |
| } |
| |
| <span class="kw">fn </span>build_jfif_header(m: <span class="kw-2">&mut </span>Vec<u8>, density: PixelDensity) { |
| m.clear(); |
| m.extend_from_slice(<span class="string">b"JFIF"</span>); |
| m.extend_from_slice(<span class="kw-2">&</span>[<span class="number">0</span>, <span class="number">0x01</span>, <span class="number">0x02</span>, |
| <span class="kw">match </span>density.unit { |
| PixelDensityUnit::PixelAspectRatio => <span class="number">0x00</span>, |
| PixelDensityUnit::Inches => <span class="number">0x01</span>, |
| PixelDensityUnit::Centimeters => <span class="number">0x02</span>, |
| }]); |
| m.extend_from_slice(<span class="kw-2">&</span>density.density.<span class="number">0</span>.to_be_bytes()); |
| m.extend_from_slice(<span class="kw-2">&</span>density.density.<span class="number">1</span>.to_be_bytes()); |
| m.extend_from_slice(<span class="kw-2">&</span>[<span class="number">0</span>, <span class="number">0</span>]); |
| } |
| |
| <span class="kw">fn </span>build_frame_header( |
| m: <span class="kw-2">&mut </span>Vec<u8>, |
| precision: u8, |
| width: u16, |
| height: u16, |
| components: <span class="kw-2">&</span>[Component], |
| ) { |
| m.clear(); |
| |
| m.push(precision); |
| m.extend_from_slice(<span class="kw-2">&</span>height.to_be_bytes()); |
| m.extend_from_slice(<span class="kw-2">&</span>width.to_be_bytes()); |
| m.push(components.len() <span class="kw">as </span>u8); |
| |
| <span class="kw">for </span><span class="kw-2">&</span>comp <span class="kw">in </span>components.iter() { |
| <span class="kw">let </span>hv = (comp.h << <span class="number">4</span>) | comp.v; |
| m.extend_from_slice(<span class="kw-2">&</span>[comp.id, hv, comp.tq]); |
| } |
| } |
| |
| <span class="kw">fn </span>build_scan_header(m: <span class="kw-2">&mut </span>Vec<u8>, components: <span class="kw-2">&</span>[Component]) { |
| m.clear(); |
| |
| m.push(components.len() <span class="kw">as </span>u8); |
| |
| <span class="kw">for </span><span class="kw-2">&</span>comp <span class="kw">in </span>components.iter() { |
| <span class="kw">let </span>tables = (comp.dc_table << <span class="number">4</span>) | comp.ac_table; |
| m.extend_from_slice(<span class="kw-2">&</span>[comp.id, tables]); |
| } |
| |
| <span class="comment">// spectral start and end, approx. high and low |
| </span>m.extend_from_slice(<span class="kw-2">&</span>[<span class="number">0</span>, <span class="number">63</span>, <span class="number">0</span>]); |
| } |
| |
| <span class="kw">fn </span>build_huffman_segment( |
| m: <span class="kw-2">&mut </span>Vec<u8>, |
| class: u8, |
| destination: u8, |
| numcodes: <span class="kw-2">&</span>[u8; <span class="number">16</span>], |
| values: <span class="kw-2">&</span>[u8], |
| ) { |
| m.clear(); |
| |
| <span class="kw">let </span>tcth = (class << <span class="number">4</span>) | destination; |
| m.push(tcth); |
| |
| m.extend_from_slice(numcodes); |
| |
| <span class="kw">let </span>sum: usize = numcodes |
| .iter() |
| .map(|<span class="kw-2">&</span>x| x <span class="kw">as </span>usize) |
| .sum(); |
| |
| <span class="macro">assert_eq!</span>(sum, values.len()); |
| |
| m.extend_from_slice(values); |
| } |
| |
| <span class="kw">fn </span>build_quantization_segment(m: <span class="kw-2">&mut </span>Vec<u8>, precision: u8, identifier: u8, qtable: <span class="kw-2">&</span>[u8; <span class="number">64</span>]) { |
| m.clear(); |
| |
| <span class="kw">let </span>p = <span class="kw">if </span>precision == <span class="number">8 </span>{ <span class="number">0 </span>} <span class="kw">else </span>{ <span class="number">1 </span>}; |
| |
| <span class="kw">let </span>pqtq = (p << <span class="number">4</span>) | identifier; |
| m.push(pqtq); |
| |
| <span class="kw">for </span><span class="kw-2">&</span>i <span class="kw">in </span><span class="kw-2">&</span>UNZIGZAG[..] { |
| m.push(qtable[i <span class="kw">as </span>usize]); |
| } |
| } |
| |
| <span class="kw">fn </span>encode_coefficient(coefficient: i32) -> (u8, u16) { |
| <span class="kw">let </span><span class="kw-2">mut </span>magnitude = coefficient.abs() <span class="kw">as </span>u16; |
| <span class="kw">let </span><span class="kw-2">mut </span>num_bits = <span class="number">0u8</span>; |
| |
| <span class="kw">while </span>magnitude > <span class="number">0 </span>{ |
| magnitude >>= <span class="number">1</span>; |
| num_bits += <span class="number">1</span>; |
| } |
| |
| <span class="kw">let </span>mask = (<span class="number">1 </span><< num_bits <span class="kw">as </span>usize) - <span class="number">1</span>; |
| |
| <span class="kw">let </span>val = <span class="kw">if </span>coefficient < <span class="number">0 </span>{ |
| (coefficient - <span class="number">1</span>) <span class="kw">as </span>u16 & mask |
| } <span class="kw">else </span>{ |
| coefficient <span class="kw">as </span>u16 & mask |
| }; |
| |
| (num_bits, val) |
| } |
| |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>rgb_to_ycbcr<P: Pixel>(pixel: P) -> (u8, u8, u8) { |
| <span class="kw">use </span>num_traits::{cast::ToPrimitive, bounds::Bounded}; |
| <span class="kw">let </span>[r, g, b] = pixel.to_rgb().<span class="number">0</span>; |
| <span class="kw">let </span>max: f32 = P::Subpixel::max_value().to_f32().unwrap(); |
| <span class="kw">let </span>r: f32 = r.to_f32().unwrap(); |
| <span class="kw">let </span>g: f32 = g.to_f32().unwrap(); |
| <span class="kw">let </span>b: f32 = b.to_f32().unwrap(); |
| |
| <span class="comment">// Coefficients from JPEG File Interchange Format (Version 1.02), multiplied for 255 maximum. |
| </span><span class="kw">let </span>y = <span class="number">76.245 </span>/ max * r + <span class="number">149.685 </span>/ max * g + <span class="number">29.07 </span>/ max * b; |
| <span class="kw">let </span>cb = -<span class="number">43.0185 </span>/ max * r - <span class="number">84.4815 </span>/ max * g + <span class="number">127.5 </span>/ max * b + <span class="number">128.</span>; |
| <span class="kw">let </span>cr = <span class="number">127.5 </span>/ max * r - <span class="number">106.7685 </span>/ max * g - <span class="number">20.7315 </span>/ max * b + <span class="number">128.</span>; |
| |
| (y <span class="kw">as </span>u8, cb <span class="kw">as </span>u8, cr <span class="kw">as </span>u8) |
| } |
| |
| |
| <span class="doccomment">/// Returns the pixel at (x,y) if (x,y) is in the image, |
| /// otherwise the closest pixel in the image |
| </span><span class="attribute">#[inline] |
| </span><span class="kw">fn </span>pixel_at_or_near<I: GenericImageView>(source: <span class="kw-2">&</span>I, x: u32, y: u32) -> I::Pixel { |
| <span class="kw">if </span>source.in_bounds(x, y) { |
| source.get_pixel(x, y) |
| } <span class="kw">else </span>{ |
| source.get_pixel( |
| x.min(source.width() - <span class="number">1</span>), |
| y.min(source.height() - <span class="number">1</span>), |
| ) |
| } |
| } |
| |
| <span class="kw">fn </span>copy_blocks_ycbcr<I: GenericImageView>( |
| source: <span class="kw-2">&</span>I, |
| x0: u32, |
| y0: u32, |
| yb: <span class="kw-2">&mut </span>[u8; <span class="number">64</span>], |
| cbb: <span class="kw-2">&mut </span>[u8; <span class="number">64</span>], |
| crb: <span class="kw-2">&mut </span>[u8; <span class="number">64</span>], |
| ) { |
| <span class="kw">for </span>y <span class="kw">in </span><span class="number">0</span>..<span class="number">8 </span>{ |
| <span class="kw">for </span>x <span class="kw">in </span><span class="number">0</span>..<span class="number">8 </span>{ |
| <span class="kw">let </span>pixel = pixel_at_or_near(source, x + x0, y + y0); |
| <span class="kw">let </span>(yc, cb, cr) = rgb_to_ycbcr(pixel); |
| |
| yb[(y * <span class="number">8 </span>+ x) <span class="kw">as </span>usize] = yc; |
| cbb[(y * <span class="number">8 </span>+ x) <span class="kw">as </span>usize] = cb; |
| crb[(y * <span class="number">8 </span>+ x) <span class="kw">as </span>usize] = cr; |
| } |
| } |
| } |
| |
| <span class="kw">fn </span>copy_blocks_gray<I: GenericImageView>( |
| source: <span class="kw-2">&</span>I, |
| x0: u32, |
| y0: u32, |
| gb: <span class="kw-2">&mut </span>[u8; <span class="number">64</span>], |
| ) { |
| <span class="kw">use </span>num_traits::cast::ToPrimitive; |
| <span class="kw">for </span>y <span class="kw">in </span><span class="number">0</span>..<span class="number">8 </span>{ |
| <span class="kw">for </span>x <span class="kw">in </span><span class="number">0</span>..<span class="number">8 </span>{ |
| <span class="kw">let </span>pixel = pixel_at_or_near(source, x0 + x, y0 + y); |
| <span class="kw">let </span>[luma] = pixel.to_luma().<span class="number">0</span>; |
| gb[(y * <span class="number">8 </span>+ x) <span class="kw">as </span>usize] = luma.to_u8().unwrap(); |
| } |
| } |
| } |
| |
| <span class="attribute">#[cfg(test)] |
| </span><span class="kw">mod </span>tests { |
| <span class="kw">use </span>std::io::Cursor; |
| |
| <span class="attribute">#[cfg(feature = <span class="string">"benchmarks"</span>)] |
| </span><span class="kw">extern crate </span>test; |
| <span class="attribute">#[cfg(feature = <span class="string">"benchmarks"</span>)] |
| </span><span class="kw">use </span>test::{Bencher}; |
| |
| <span class="kw">use crate</span>::{Bgra, ImageBuffer, ImageEncoder, ImageError}; |
| <span class="kw">use </span><span class="kw">crate</span>::color::ColorType; |
| <span class="kw">use </span><span class="kw">crate</span>::error::ParameterErrorKind::DimensionMismatch; |
| <span class="kw">use </span><span class="kw">crate</span>::image::ImageDecoder; |
| |
| <span class="kw">use super</span>::{ |
| build_jfif_header, |
| build_huffman_segment, |
| build_scan_header, |
| build_quantization_segment, |
| build_frame_header, |
| Component, |
| DCCLASS, |
| JpegEncoder, |
| LUMADESTINATION, |
| PixelDensity, |
| STD_LUMA_DC_CODE_LENGTHS, |
| STD_LUMA_DC_VALUES, |
| }; |
| <span class="kw">use </span><span class="kw">super</span>::<span class="kw">super</span>::JpegDecoder; |
| |
| |
| <span class="kw">fn </span>decode(encoded: <span class="kw-2">&</span>[u8]) -> Vec<u8> { |
| <span class="kw">let </span>decoder = JpegDecoder::new(Cursor::new(encoded)) |
| .expect(<span class="string">"Could not decode image"</span>); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>decoded = <span class="macro">vec!</span>[<span class="number">0</span>; decoder.total_bytes() <span class="kw">as </span>usize]; |
| decoder.read_image(<span class="kw-2">&mut </span>decoded).expect(<span class="string">"Could not decode image"</span>); |
| decoded |
| } |
| |
| <span class="attribute">#[test] |
| </span><span class="kw">fn </span>roundtrip_sanity_check() { |
| <span class="comment">// create a 1x1 8-bit image buffer containing a single red pixel |
| </span><span class="kw">let </span>img = [<span class="number">255u8</span>, <span class="number">0</span>, <span class="number">0</span>]; |
| |
| <span class="comment">// encode it into a memory buffer |
| </span><span class="kw">let </span><span class="kw-2">mut </span>encoded_img = Vec::new(); |
| { |
| <span class="kw">let </span>encoder = JpegEncoder::new_with_quality(<span class="kw-2">&mut </span>encoded_img, <span class="number">100</span>); |
| encoder |
| .write_image(<span class="kw-2">&</span>img, <span class="number">1</span>, <span class="number">1</span>, ColorType::Rgb8) |
| .expect(<span class="string">"Could not encode image"</span>); |
| } |
| |
| <span class="comment">// decode it from the memory buffer |
| </span>{ |
| <span class="kw">let </span>decoded = decode(<span class="kw-2">&</span>encoded_img); |
| <span class="comment">// note that, even with the encode quality set to 100, we do not get the same image |
| // back. Therefore, we're going to assert that it's at least red-ish: |
| </span><span class="macro">assert_eq!</span>(<span class="number">3</span>, decoded.len()); |
| <span class="macro">assert!</span>(decoded[<span class="number">0</span>] > <span class="number">0x80</span>); |
| <span class="macro">assert!</span>(decoded[<span class="number">1</span>] < <span class="number">0x80</span>); |
| <span class="macro">assert!</span>(decoded[<span class="number">2</span>] < <span class="number">0x80</span>); |
| } |
| } |
| |
| <span class="attribute">#[test] |
| </span><span class="kw">fn </span>grayscale_roundtrip_sanity_check() { |
| <span class="comment">// create a 2x2 8-bit image buffer containing a white diagonal |
| </span><span class="kw">let </span>img = [<span class="number">255u8</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">255</span>]; |
| |
| <span class="comment">// encode it into a memory buffer |
| </span><span class="kw">let </span><span class="kw-2">mut </span>encoded_img = Vec::new(); |
| { |
| <span class="kw">let </span>encoder = JpegEncoder::new_with_quality(<span class="kw-2">&mut </span>encoded_img, <span class="number">100</span>); |
| encoder |
| .write_image(<span class="kw-2">&</span>img[..], <span class="number">2</span>, <span class="number">2</span>, ColorType::L8) |
| .expect(<span class="string">"Could not encode image"</span>); |
| } |
| |
| <span class="comment">// decode it from the memory buffer |
| </span>{ |
| <span class="kw">let </span>decoded = decode(<span class="kw-2">&</span>encoded_img); |
| <span class="comment">// note that, even with the encode quality set to 100, we do not get the same image |
| // back. Therefore, we're going to assert that the diagonal is at least white-ish: |
| </span><span class="macro">assert_eq!</span>(<span class="number">4</span>, decoded.len()); |
| <span class="macro">assert!</span>(decoded[<span class="number">0</span>] > <span class="number">0x80</span>); |
| <span class="macro">assert!</span>(decoded[<span class="number">1</span>] < <span class="number">0x80</span>); |
| <span class="macro">assert!</span>(decoded[<span class="number">2</span>] < <span class="number">0x80</span>); |
| <span class="macro">assert!</span>(decoded[<span class="number">3</span>] > <span class="number">0x80</span>); |
| } |
| } |
| |
| <span class="attribute">#[test] |
| </span><span class="kw">fn </span>jfif_header_density_check() { |
| <span class="kw">let </span><span class="kw-2">mut </span>buffer = Vec::new(); |
| build_jfif_header(<span class="kw-2">&mut </span>buffer, PixelDensity::dpi(<span class="number">300</span>)); |
| <span class="macro">assert_eq!</span>(buffer, <span class="macro">vec!</span>[ |
| <span class="string">b'J'</span>, <span class="string">b'F'</span>, <span class="string">b'I'</span>, <span class="string">b'F'</span>, |
| <span class="number">0</span>, <span class="number">1</span>, <span class="number">2</span>, <span class="comment">// JFIF version 1.2 |
| </span><span class="number">1</span>, <span class="comment">// density is in dpi |
| </span><span class="number">300u16</span>.to_be_bytes()[<span class="number">0</span>], <span class="number">300u16</span>.to_be_bytes()[<span class="number">1</span>], |
| <span class="number">300u16</span>.to_be_bytes()[<span class="number">0</span>], <span class="number">300u16</span>.to_be_bytes()[<span class="number">1</span>], |
| <span class="number">0</span>, <span class="number">0</span>, <span class="comment">// No thumbnail |
| </span>] |
| ); |
| } |
| |
| <span class="attribute">#[test] |
| </span><span class="kw">fn </span>test_image_too_large() { |
| <span class="comment">// JPEG cannot encode images larger than 65,535×65,535 |
| // create a 65,536×1 8-bit black image buffer |
| </span><span class="kw">let </span>img = [<span class="number">0</span>; <span class="number">65_536</span>]; |
| <span class="comment">// Try to encode an image that is too large |
| </span><span class="kw">let </span><span class="kw-2">mut </span>encoded = Vec::new(); |
| <span class="kw">let </span>encoder = JpegEncoder::new_with_quality(<span class="kw-2">&mut </span>encoded, <span class="number">100</span>); |
| <span class="kw">let </span>result = encoder.write_image(<span class="kw-2">&</span>img, <span class="number">65_536</span>, <span class="number">1</span>, ColorType::L8); |
| <span class="kw">match </span>result { |
| <span class="prelude-val">Err</span>(ImageError::Parameter(err)) => { |
| <span class="macro">assert_eq!</span>(err.kind(), DimensionMismatch) |
| } |
| other => { |
| <span class="macro">assert!</span>(<span class="bool-val">false</span>, <span class="string">"Encoding an image that is too large should return a DimensionError \ |
| it returned {:?} instead"</span>, other) |
| } |
| } |
| } |
| |
| <span class="attribute">#[test] |
| </span><span class="kw">fn </span>test_bgra16() { |
| <span class="comment">// Test encoding an RGBA 16-bit image. |
| // Jpeg is RGB 8-bit, so the conversion should be done on the fly |
| </span><span class="kw">let </span><span class="kw-2">mut </span>encoded = Vec::new(); |
| <span class="kw">let </span>max = std::u16::MAX; |
| <span class="kw">let </span>image: ImageBuffer<Bgra<u16>, <span class="kw">_</span>> = ImageBuffer::from_raw( |
| <span class="number">1</span>, <span class="number">1</span>, <span class="macro">vec!</span>[<span class="number">0</span>, max / <span class="number">2</span>, max, max]).unwrap(); |
| <span class="kw">let </span><span class="kw-2">mut </span>encoder = JpegEncoder::new_with_quality(<span class="kw-2">&mut </span>encoded, <span class="number">100</span>); |
| encoder.encode_image(<span class="kw-2">&</span>image).unwrap(); |
| <span class="kw">let </span>decoded = decode(<span class="kw-2">&</span>encoded); |
| <span class="macro">assert!</span>(decoded[<span class="number">0</span>] > <span class="number">200</span>, <span class="string">"bad red channel in {:?}"</span>, <span class="kw-2">&</span>decoded); |
| <span class="macro">assert!</span>(<span class="number">100 </span>< decoded[<span class="number">1</span>] && decoded[<span class="number">1</span>] < <span class="number">150</span>, <span class="string">"bad green channel in {:?}"</span>, <span class="kw-2">&</span>decoded); |
| <span class="macro">assert!</span>(decoded[<span class="number">2</span>] < <span class="number">50</span>, <span class="string">"bad blue channel in {:?}"</span>, <span class="kw-2">&</span>decoded); |
| } |
| |
| <span class="attribute">#[test] |
| </span><span class="kw">fn </span>test_build_jfif_header() { |
| <span class="kw">let </span><span class="kw-2">mut </span>buf = <span class="macro">vec!</span>[]; |
| <span class="kw">let </span>density = PixelDensity::dpi(<span class="number">100</span>); |
| build_jfif_header(<span class="kw-2">&mut </span>buf, density); |
| <span class="macro">assert_eq!</span>(buf, [<span class="number">0x4A</span>, <span class="number">0x46</span>, <span class="number">0x49</span>, <span class="number">0x46</span>, <span class="number">0x00</span>, <span class="number">0x01</span>, <span class="number">0x02</span>, <span class="number">0x01</span>, <span class="number">0</span>, <span class="number">100</span>, <span class="number">0</span>, <span class="number">100</span>, <span class="number">0</span>, <span class="number">0</span>]); |
| } |
| |
| <span class="attribute">#[test] |
| </span><span class="kw">fn </span>test_build_frame_header() { |
| <span class="kw">let </span><span class="kw-2">mut </span>buf = <span class="macro">vec!</span>[]; |
| <span class="kw">let </span>components = <span class="macro">vec!</span>[ |
| Component { |
| id: <span class="number">1</span>, |
| h: <span class="number">1</span>, |
| v: <span class="number">1</span>, |
| tq: <span class="number">5</span>, |
| dc_table: <span class="number">5</span>, |
| ac_table: <span class="number">5</span>, |
| _dc_pred: <span class="number">0</span>, |
| }, |
| Component { |
| id: <span class="number">2</span>, |
| h: <span class="number">1</span>, |
| v: <span class="number">1</span>, |
| tq: <span class="number">4</span>, |
| dc_table: <span class="number">4</span>, |
| ac_table: <span class="number">4</span>, |
| _dc_pred: <span class="number">0</span>, |
| }, |
| ]; |
| build_frame_header(<span class="kw-2">&mut </span>buf, <span class="number">5</span>, <span class="number">100</span>, <span class="number">150</span>, <span class="kw-2">&</span>components); |
| <span class="macro">assert_eq!</span>(buf, [<span class="number">5</span>, <span class="number">0</span>, <span class="number">150</span>, <span class="number">0</span>, <span class="number">100</span>, <span class="number">2</span>, <span class="number">1</span>, <span class="number">1 </span><< <span class="number">4 </span>| <span class="number">1</span>, <span class="number">5</span>, <span class="number">2</span>, <span class="number">1 </span><< <span class="number">4 </span>| <span class="number">1</span>, <span class="number">4</span>]); |
| } |
| |
| <span class="attribute">#[test] |
| </span><span class="kw">fn </span>test_build_scan_header() { |
| <span class="kw">let </span><span class="kw-2">mut </span>buf = <span class="macro">vec!</span>[]; |
| <span class="kw">let </span>components = <span class="macro">vec!</span>[ |
| Component { |
| id: <span class="number">1</span>, |
| h: <span class="number">1</span>, |
| v: <span class="number">1</span>, |
| tq: <span class="number">5</span>, |
| dc_table: <span class="number">5</span>, |
| ac_table: <span class="number">5</span>, |
| _dc_pred: <span class="number">0</span>, |
| }, |
| Component { |
| id: <span class="number">2</span>, |
| h: <span class="number">1</span>, |
| v: <span class="number">1</span>, |
| tq: <span class="number">4</span>, |
| dc_table: <span class="number">4</span>, |
| ac_table: <span class="number">4</span>, |
| _dc_pred: <span class="number">0</span>, |
| }, |
| ]; |
| build_scan_header(<span class="kw-2">&mut </span>buf, <span class="kw-2">&</span>components); |
| <span class="macro">assert_eq!</span>(buf, [<span class="number">2</span>, <span class="number">1</span>, <span class="number">5 </span><< <span class="number">4 </span>| <span class="number">5</span>, <span class="number">2</span>, <span class="number">4 </span><< <span class="number">4 </span>| <span class="number">4</span>, <span class="number">0</span>, <span class="number">63</span>, <span class="number">0</span>]); |
| } |
| |
| <span class="attribute">#[test] |
| </span><span class="kw">fn </span>test_build_huffman_segment() { |
| <span class="kw">let </span><span class="kw-2">mut </span>buf = <span class="macro">vec!</span>[]; |
| build_huffman_segment( |
| <span class="kw-2">&mut </span>buf, |
| DCCLASS, |
| LUMADESTINATION, |
| <span class="kw-2">&</span>STD_LUMA_DC_CODE_LENGTHS, |
| <span class="kw-2">&</span>STD_LUMA_DC_VALUES, |
| ); |
| <span class="macro">assert_eq!</span>(buf, <span class="macro">vec!</span>[<span class="number">0</span>, <span class="number">0</span>, <span class="number">1</span>, <span class="number">5</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">1</span>, <span class="number">2</span>, <span class="number">3</span>, <span class="number">4</span>, <span class="number">5</span>, <span class="number">6</span>, <span class="number">7</span>, <span class="number">8</span>, <span class="number">9</span>, <span class="number">10</span>, <span class="number">11</span>]); |
| } |
| |
| <span class="attribute">#[test] |
| </span><span class="kw">fn </span>test_build_quantization_segment() { |
| <span class="kw">let </span><span class="kw-2">mut </span>buf = <span class="macro">vec!</span>[]; |
| <span class="kw">let </span>qtable = [<span class="number">0u8</span>; <span class="number">64</span>]; |
| build_quantization_segment(<span class="kw-2">&mut </span>buf, <span class="number">8</span>, <span class="number">1</span>, <span class="kw-2">&</span>qtable); |
| <span class="kw">let </span><span class="kw-2">mut </span>expected = <span class="macro">vec!</span>[]; |
| expected.push(<span class="number">0 </span><< <span class="number">4 </span>| <span class="number">1</span>); |
| expected.extend_from_slice(<span class="kw-2">&</span>[<span class="number">0</span>; <span class="number">64</span>]); |
| <span class="macro">assert_eq!</span>(buf, expected) |
| } |
| |
| <span class="attribute">#[cfg(feature = <span class="string">"benchmarks"</span>)] |
| #[bench] |
| </span><span class="kw">fn </span>bench_jpeg_encoder_new(b: <span class="kw-2">&mut </span>Bencher) { |
| b.iter(|| { |
| <span class="kw">let </span><span class="kw-2">mut </span>y = <span class="macro">vec!</span>[]; |
| <span class="kw">let </span>x = JpegEncoder::new(<span class="kw-2">&mut </span>y); |
| }) |
| } |
| |
| } |
| </code></pre></div> |
| </section></div></main><div id="rustdoc-vars" data-root-path="../../../../" data-current-crate="image" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |
