| <!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="The representation of a JPEG encoder"><meta name="keywords" content="rust, rustlang, rust-lang, JpegEncoder"><title>JpegEncoder in image::codecs::jpeg - Rust</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 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class="mobile-topbar"><button class="sidebar-menu-toggle">☰</button><a class="sidebar-logo" href="../../../image/index.html"><div class="logo-container"><img class="rust-logo" src="../../../rust-logo.svg" alt="logo"></div></a><h2></h2></nav><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><h2 class="location"><a href="#">JpegEncoder</a></h2><div class="sidebar-elems"><section><h3><a href="#implementations">Methods</a></h3><ul class="block"><li><a href="#method.encode">encode</a></li><li><a href="#method.encode_image">encode_image</a></li><li><a href="#method.new">new</a></li><li><a href="#method.new_with_quality">new_with_quality</a></li><li><a href="#method.set_pixel_density">set_pixel_density</a></li></ul><h3><a href="#trait-implementations">Trait Implementations</a></h3><ul class="block"><li><a href="#impl-ImageEncoder-for-JpegEncoder%3C%27a%2C%20W%3E">ImageEncoder</a></li></ul><h3><a href="#synthetic-implementations">Auto Trait Implementations</a></h3><ul class="block"><li><a href="#impl-RefUnwindSafe-for-JpegEncoder%3C%27a%2C%20W%3E">RefUnwindSafe</a></li><li><a href="#impl-Send-for-JpegEncoder%3C%27a%2C%20W%3E">Send</a></li><li><a href="#impl-Sync-for-JpegEncoder%3C%27a%2C%20W%3E">Sync</a></li><li><a href="#impl-Unpin-for-JpegEncoder%3C%27a%2C%20W%3E">Unpin</a></li><li><a href="#impl-UnwindSafe-for-JpegEncoder%3C%27a%2C%20W%3E">!UnwindSafe</a></li></ul><h3><a href="#blanket-implementations">Blanket Implementations</a></h3><ul class="block"><li><a href="#impl-Any-for-JpegEncoder%3C%27a%2C%20W%3E">Any</a></li><li><a href="#impl-Borrow%3CT%3E-for-JpegEncoder%3C%27a%2C%20W%3E">Borrow<T></a></li><li><a href="#impl-BorrowMut%3CT%3E-for-JpegEncoder%3C%27a%2C%20W%3E">BorrowMut<T></a></li><li><a href="#impl-From%3CT%3E-for-JpegEncoder%3C%27a%2C%20W%3E">From<T></a></li><li><a href="#impl-Into%3CU%3E-for-JpegEncoder%3C%27a%2C%20W%3E">Into<U></a></li><li><a href="#impl-TryFrom%3CU%3E-for-JpegEncoder%3C%27a%2C%20W%3E">TryFrom<U></a></li><li><a href="#impl-TryInto%3CU%3E-for-JpegEncoder%3C%27a%2C%20W%3E">TryInto<U></a></li></ul></section><h2><a href="index.html">In image::codecs::jpeg</a></h2></div></nav><main><div class="width-limiter"><nav class="sub"><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="main-heading"><h1 class="fqn">Struct <a href="../../index.html">image</a>::<wbr><a href="../index.html">codecs</a>::<wbr><a href="index.html">jpeg</a>::<wbr><a class="struct" href="#">JpegEncoder</a><button id="copy-path" onclick="copy_path(this)" title="Copy item path to clipboard"><img src="../../../clipboard.svg" width="19" height="18" alt="Copy item path"></button></h1><span class="out-of-band"><a class="srclink" href="../../../src/image/codecs/jpeg/encoder.rs.html#324-336">source</a> · <a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">[<span class="inner">−</span>]</a></span></div><div class="item-decl"><pre class="rust struct"><code>pub struct JpegEncoder<'a, W: 'a> { /* private fields */ }</code></pre></div><details class="rustdoc-toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>The representation of a JPEG encoder</p> |
| </div></details><h2 id="implementations" class="small-section-header">Implementations<a href="#implementations" class="anchor"></a></h2><div id="implementations-list"><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-JpegEncoder%3C%27a%2C%20W%3E" class="impl has-srclink"><a class="srclink rightside" href="../../../src/image/codecs/jpeg/encoder.rs.html#349-675">source</a><a href="#impl-JpegEncoder%3C%27a%2C%20W%3E" class="anchor"></a><h3 class="code-header">impl<'a, W: Write> <a class="struct" href="struct.JpegEncoder.html" title="struct image::codecs::jpeg::JpegEncoder">JpegEncoder</a><'a, W></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.new" class="method has-srclink"><a class="srclink rightside" href="../../../src/image/codecs/jpeg/encoder.rs.html#351-353">source</a><h4 class="code-header">pub fn <a href="#method.new" class="fnname">new</a>(w: &mut W) -> <a class="struct" href="struct.JpegEncoder.html" title="struct image::codecs::jpeg::JpegEncoder">JpegEncoder</a><'_, W></h4></section></summary><div class="docblock"><p>Create a new encoder that writes its output to <code>w</code></p> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.new_with_quality" class="method has-srclink"><a class="srclink rightside" href="../../../src/image/codecs/jpeg/encoder.rs.html#358-425">source</a><h4 class="code-header">pub fn <a href="#method.new_with_quality" class="fnname">new_with_quality</a>(w: &mut W, quality: u8) -> <a class="struct" href="struct.JpegEncoder.html" title="struct image::codecs::jpeg::JpegEncoder">JpegEncoder</a><'_, W></h4></section></summary><div class="docblock"><p>Create a new encoder that writes its output to <code>w</code>, and has |
| the quality parameter <code>quality</code> with a value in the range 1-100 |
| where 1 is the worst and 100 is the best.</p> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.set_pixel_density" class="method has-srclink"><a class="srclink rightside" href="../../../src/image/codecs/jpeg/encoder.rs.html#430-432">source</a><h4 class="code-header">pub fn <a href="#method.set_pixel_density" class="fnname">set_pixel_density</a>(&mut self, pixel_density: <a class="struct" href="struct.PixelDensity.html" title="struct image::codecs::jpeg::PixelDensity">PixelDensity</a>)</h4></section></summary><div class="docblock"><p>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.</p> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.encode" class="method has-srclink"><a class="srclink rightside" href="../../../src/image/codecs/jpeg/encoder.rs.html#439-480">source</a><h4 class="code-header">pub fn <a href="#method.encode" class="fnname">encode</a>(<br> &mut self,<br> image: &[u8],<br> width: u32,<br> height: u32,<br> color_type: <a class="enum" href="../../enum.ColorType.html" title="enum image::ColorType">ColorType</a><br>) -> <a class="type" href="../../error/type.ImageResult.html" title="type image::error::ImageResult">ImageResult</a><()></h4></section></summary><div class="docblock"><p>Encodes the image stored in the raw byte buffer <code>image</code> |
| that has dimensions <code>width</code> and <code>height</code> |
| and <code>ColorType</code> <code>c</code></p> |
| <p>The Image in encoded with subsampling ratio 4:2:2</p> |
| </div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.encode_image" class="method has-srclink"><a class="srclink rightside" href="../../../src/image/codecs/jpeg/encoder.rs.html#491-583">source</a><h4 class="code-header">pub fn <a href="#method.encode_image" class="fnname">encode_image</a><I: <a class="trait" href="../../trait.GenericImageView.html" title="trait image::GenericImageView">GenericImageView</a>>(&mut self, image: &I) -> <a class="type" href="../../error/type.ImageResult.html" title="type image::error::ImageResult">ImageResult</a><()></h4></section></summary><div class="docblock"><p>Encodes the given image.</p> |
| <p>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.</p> |
| <p>The Image in encoded with subsampling ratio 4:2:2</p> |
| </div></details></div></details></div><h2 id="trait-implementations" class="small-section-header">Trait Implementations<a href="#trait-implementations" class="anchor"></a></h2><div id="trait-implementations-list"><details class="rustdoc-toggle implementors-toggle" open><summary><section id="impl-ImageEncoder-for-JpegEncoder%3C%27a%2C%20W%3E" class="impl has-srclink"><a class="srclink rightside" href="../../../src/image/codecs/jpeg/encoder.rs.html#677-687">source</a><a href="#impl-ImageEncoder-for-JpegEncoder%3C%27a%2C%20W%3E" class="anchor"></a><h3 class="code-header">impl<'a, W: Write> <a class="trait" href="../../trait.ImageEncoder.html" title="trait image::ImageEncoder">ImageEncoder</a> for <a class="struct" href="struct.JpegEncoder.html" title="struct image::codecs::jpeg::JpegEncoder">JpegEncoder</a><'a, W></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.write_image" class="method trait-impl has-srclink"><a class="srclink rightside" href="../../../src/image/codecs/jpeg/encoder.rs.html#678-686">source</a><a href="#method.write_image" class="anchor"></a><h4 class="code-header">fn <a href="../../trait.ImageEncoder.html#tymethod.write_image" class="fnname">write_image</a>(<br> self,<br> buf: &[u8],<br> width: u32,<br> height: u32,<br> color_type: <a class="enum" href="../../enum.ColorType.html" title="enum image::ColorType">ColorType</a><br>) -> <a class="type" href="../../error/type.ImageResult.html" title="type image::error::ImageResult">ImageResult</a><()></h4></section></summary><div class='docblock'>Writes all the bytes in an image to the encoder. <a href="../../trait.ImageEncoder.html#tymethod.write_image">Read more</a></div></details></div></details></div><h2 id="synthetic-implementations" class="small-section-header">Auto Trait Implementations<a href="#synthetic-implementations" class="anchor"></a></h2><div id="synthetic-implementations-list"><section id="impl-RefUnwindSafe-for-JpegEncoder%3C%27a%2C%20W%3E" class="impl has-srclink"><a href="#impl-RefUnwindSafe-for-JpegEncoder%3C%27a%2C%20W%3E" class="anchor"></a><h3 class="code-header">impl<'a, W> RefUnwindSafe for <a class="struct" href="struct.JpegEncoder.html" title="struct image::codecs::jpeg::JpegEncoder">JpegEncoder</a><'a, W><span class="where fmt-newline">where<br> W: RefUnwindSafe,</span></h3></section><section id="impl-Send-for-JpegEncoder%3C%27a%2C%20W%3E" class="impl has-srclink"><a href="#impl-Send-for-JpegEncoder%3C%27a%2C%20W%3E" class="anchor"></a><h3 class="code-header">impl<'a, W> Send for <a class="struct" href="struct.JpegEncoder.html" title="struct image::codecs::jpeg::JpegEncoder">JpegEncoder</a><'a, W><span class="where fmt-newline">where<br> W: Send,</span></h3></section><section id="impl-Sync-for-JpegEncoder%3C%27a%2C%20W%3E" class="impl has-srclink"><a href="#impl-Sync-for-JpegEncoder%3C%27a%2C%20W%3E" class="anchor"></a><h3 class="code-header">impl<'a, W> Sync for <a class="struct" href="struct.JpegEncoder.html" title="struct image::codecs::jpeg::JpegEncoder">JpegEncoder</a><'a, W><span class="where fmt-newline">where<br> W: Sync,</span></h3></section><section id="impl-Unpin-for-JpegEncoder%3C%27a%2C%20W%3E" class="impl has-srclink"><a href="#impl-Unpin-for-JpegEncoder%3C%27a%2C%20W%3E" class="anchor"></a><h3 class="code-header">impl<'a, W> Unpin for <a class="struct" href="struct.JpegEncoder.html" title="struct image::codecs::jpeg::JpegEncoder">JpegEncoder</a><'a, W></h3></section><section id="impl-UnwindSafe-for-JpegEncoder%3C%27a%2C%20W%3E" class="impl has-srclink"><a href="#impl-UnwindSafe-for-JpegEncoder%3C%27a%2C%20W%3E" class="anchor"></a><h3 class="code-header">impl<'a, W> !UnwindSafe for <a class="struct" href="struct.JpegEncoder.html" title="struct image::codecs::jpeg::JpegEncoder">JpegEncoder</a><'a, W></h3></section></div><h2 id="blanket-implementations" class="small-section-header">Blanket Implementations<a href="#blanket-implementations" class="anchor"></a></h2><div id="blanket-implementations-list"><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-Any-for-JpegEncoder%3C%27a%2C%20W%3E" class="impl has-srclink"><a href="#impl-Any-for-JpegEncoder%3C%27a%2C%20W%3E" class="anchor"></a><h3 class="code-header">impl<T> Any for T<span class="where fmt-newline">where<br> T: 'static + ?Sized,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.type_id" class="method trait-impl has-srclink"><a href="#method.type_id" class="anchor"></a><h4 class="code-header">fn <a class="fnname">type_id</a>(&self) -> TypeId</h4></section></summary><div class='docblock'>Gets the <code>TypeId</code> of <code>self</code>. <a>Read more</a></div></details></div></details><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-Borrow%3CT%3E-for-JpegEncoder%3C%27a%2C%20W%3E" class="impl has-srclink"><a href="#impl-Borrow%3CT%3E-for-JpegEncoder%3C%27a%2C%20W%3E" class="anchor"></a><h3 class="code-header">impl<T> Borrow<T> for T<span class="where fmt-newline">where<br> T: ?Sized,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.borrow" class="method trait-impl has-srclink"><span class="since rightside" title="const unstable">const: <a href="https://github.com/rust-lang/rust/issues/91522" title="Tracking issue for const_borrow">unstable</a></span><a href="#method.borrow" class="anchor"></a><h4 class="code-header">fn <a class="fnname">borrow</a>(&self) -> &T</h4></section></summary><div class='docblock'>Immutably borrows from an owned value. <a>Read more</a></div></details></div></details><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-BorrowMut%3CT%3E-for-JpegEncoder%3C%27a%2C%20W%3E" class="impl has-srclink"><a href="#impl-BorrowMut%3CT%3E-for-JpegEncoder%3C%27a%2C%20W%3E" class="anchor"></a><h3 class="code-header">impl<T> BorrowMut<T> for T<span class="where fmt-newline">where<br> T: ?Sized,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.borrow_mut" class="method trait-impl has-srclink"><span class="since rightside" title="const unstable">const: <a href="https://github.com/rust-lang/rust/issues/91522" title="Tracking issue for const_borrow">unstable</a></span><a href="#method.borrow_mut" class="anchor"></a><h4 class="code-header">fn <a class="fnname">borrow_mut</a>(&mut self) -> &mut T</h4></section></summary><div class='docblock'>Mutably borrows from an owned value. <a>Read more</a></div></details></div></details><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-From%3CT%3E-for-JpegEncoder%3C%27a%2C%20W%3E" class="impl has-srclink"><a href="#impl-From%3CT%3E-for-JpegEncoder%3C%27a%2C%20W%3E" class="anchor"></a><h3 class="code-header">impl<T> From<T> for T</h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.from" class="method trait-impl has-srclink"><span class="since rightside" title="const unstable">const: <a href="https://github.com/rust-lang/rust/issues/88674" title="Tracking issue for const_convert">unstable</a></span><a href="#method.from" class="anchor"></a><h4 class="code-header">fn <a class="fnname">from</a>(t: T) -> T</h4></section></summary><div class="docblock"><p>Returns the argument unchanged.</p> |
| </div></details></div></details><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-Into%3CU%3E-for-JpegEncoder%3C%27a%2C%20W%3E" class="impl has-srclink"><a href="#impl-Into%3CU%3E-for-JpegEncoder%3C%27a%2C%20W%3E" class="anchor"></a><h3 class="code-header">impl<T, U> Into<U> for T<span class="where fmt-newline">where<br> U: From<T>,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle method-toggle" open><summary><section id="method.into" class="method trait-impl has-srclink"><span class="since rightside" title="const unstable">const: <a href="https://github.com/rust-lang/rust/issues/88674" title="Tracking issue for const_convert">unstable</a></span><a href="#method.into" class="anchor"></a><h4 class="code-header">fn <a class="fnname">into</a>(self) -> U</h4></section></summary><div class="docblock"><p>Calls <code>U::from(self)</code>.</p> |
| <p>That is, this conversion is whatever the implementation of |
| <code>[From]<T> for U</code> chooses to do.</p> |
| </div></details></div></details><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-TryFrom%3CU%3E-for-JpegEncoder%3C%27a%2C%20W%3E" class="impl has-srclink"><a href="#impl-TryFrom%3CU%3E-for-JpegEncoder%3C%27a%2C%20W%3E" class="anchor"></a><h3 class="code-header">impl<T, U> TryFrom<U> for T<span class="where fmt-newline">where<br> U: Into<T>,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle" open><summary><section id="associatedtype.Error-1" class="associatedtype trait-impl has-srclink"><a href="#associatedtype.Error-1" class="anchor"></a><h4 class="code-header">type <a class="associatedtype">Error</a> = Infallible</h4></section></summary><div class='docblock'>The type returned in the event of a conversion error.</div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.try_from" class="method trait-impl has-srclink"><span class="since rightside" title="const unstable">const: <a href="https://github.com/rust-lang/rust/issues/88674" title="Tracking issue for const_convert">unstable</a></span><a href="#method.try_from" class="anchor"></a><h4 class="code-header">fn <a class="fnname">try_from</a>(value: U) -> Result<T, <T as TryFrom<U>>::Error></h4></section></summary><div class='docblock'>Performs the conversion.</div></details></div></details><details class="rustdoc-toggle implementors-toggle"><summary><section id="impl-TryInto%3CU%3E-for-JpegEncoder%3C%27a%2C%20W%3E" class="impl has-srclink"><a href="#impl-TryInto%3CU%3E-for-JpegEncoder%3C%27a%2C%20W%3E" class="anchor"></a><h3 class="code-header">impl<T, U> TryInto<U> for T<span class="where fmt-newline">where<br> U: TryFrom<T>,</span></h3></section></summary><div class="impl-items"><details class="rustdoc-toggle" open><summary><section id="associatedtype.Error" class="associatedtype trait-impl has-srclink"><a href="#associatedtype.Error" class="anchor"></a><h4 class="code-header">type <a class="associatedtype">Error</a> = <U as TryFrom<T>>::Error</h4></section></summary><div class='docblock'>The type returned in the event of a conversion error.</div></details><details class="rustdoc-toggle method-toggle" open><summary><section id="method.try_into" class="method trait-impl has-srclink"><span class="since rightside" title="const unstable">const: <a href="https://github.com/rust-lang/rust/issues/88674" title="Tracking issue for const_convert">unstable</a></span><a href="#method.try_into" class="anchor"></a><h4 class="code-header">fn <a class="fnname">try_into</a>(self) -> Result<U, <U as TryFrom<T>>::Error></h4></section></summary><div class='docblock'>Performs the conversion.</div></details></div></details></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> |
