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</pre><div class="example-wrap"><pre class="rust ">
<span class="doccomment">//! Common types shared between the encoder and decoder</span>
<span class="kw">use</span> <span class="ident">filter</span>;
<span class="attribute">#[<span class="ident">derive</span>(<span class="ident">Debug</span>, <span class="ident">Clone</span>, <span class="ident">Copy</span>, <span class="ident">PartialEq</span>, <span class="ident">Eq</span>)]</span>
<span class="attribute">#[<span class="ident">repr</span>(<span class="ident">u8</span>)]</span>
<span class="kw">pub</span> <span class="kw">enum</span> <span class="ident">ColorType</span> {
<span class="ident">Grayscale</span> <span class="op">=</span> <span class="number">0</span>,
<span class="ident">RGB</span> <span class="op">=</span> <span class="number">2</span>,
<span class="ident">Indexed</span> <span class="op">=</span> <span class="number">3</span>,
<span class="ident">GrayscaleAlpha</span> <span class="op">=</span> <span class="number">4</span>,
<span class="ident">RGBA</span> <span class="op">=</span> <span class="number">6</span>
}
<span class="kw">impl</span> <span class="ident">ColorType</span> {
<span class="doccomment">/// Returns the number of samples used per pixel of `ColorType`</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">samples</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-</span><span class="op">></span> <span class="ident">usize</span> {
<span class="kw">use</span> <span class="self">self</span>::<span class="ident">ColorType</span>::<span class="kw-2">*</span>;
<span class="kw">match</span> <span class="kw-2">*</span><span class="self">self</span> {
<span class="ident">Grayscale</span> <span class="op">|</span> <span class="ident">Indexed</span> <span class="op">=</span><span class="op">></span> <span class="number">1</span>,
<span class="ident">RGB</span> <span class="op">=</span><span class="op">></span> <span class="number">3</span>,
<span class="ident">GrayscaleAlpha</span> <span class="op">=</span><span class="op">></span> <span class="number">2</span>,
<span class="ident">RGBA</span> <span class="op">=</span><span class="op">></span> <span class="number">4</span>
}
}
<span class="doccomment">/// u8 -> Self. Temporary solution until Rust provides a canonical one.</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">from_u8</span>(<span class="ident">n</span>: <span class="ident">u8</span>) <span class="op">-</span><span class="op">></span> <span class="prelude-ty">Option</span><span class="op"><</span><span class="ident">ColorType</span><span class="op">></span> {
<span class="kw">match</span> <span class="ident">n</span> {
<span class="number">0</span> <span class="op">=</span><span class="op">></span> <span class="prelude-val">Some</span>(<span class="ident">ColorType</span>::<span class="ident">Grayscale</span>),
<span class="number">2</span> <span class="op">=</span><span class="op">></span> <span class="prelude-val">Some</span>(<span class="ident">ColorType</span>::<span class="ident">RGB</span>),
<span class="number">3</span> <span class="op">=</span><span class="op">></span> <span class="prelude-val">Some</span>(<span class="ident">ColorType</span>::<span class="ident">Indexed</span>),
<span class="number">4</span> <span class="op">=</span><span class="op">></span> <span class="prelude-val">Some</span>(<span class="ident">ColorType</span>::<span class="ident">GrayscaleAlpha</span>),
<span class="number">6</span> <span class="op">=</span><span class="op">></span> <span class="prelude-val">Some</span>(<span class="ident">ColorType</span>::<span class="ident">RGBA</span>),
<span class="kw">_</span> <span class="op">=</span><span class="op">></span> <span class="prelude-val">None</span>
}
}
}
<span class="doccomment">/// Bit depth of the png file</span>
<span class="attribute">#[<span class="ident">derive</span>(<span class="ident">Debug</span>, <span class="ident">Clone</span>, <span class="ident">Copy</span>, <span class="ident">PartialEq</span>, <span class="ident">Eq</span>)]</span>
<span class="attribute">#[<span class="ident">repr</span>(<span class="ident">u8</span>)]</span>
<span class="kw">pub</span> <span class="kw">enum</span> <span class="ident">BitDepth</span> {
<span class="ident">One</span> <span class="op">=</span> <span class="number">1</span>,
<span class="ident">Two</span> <span class="op">=</span> <span class="number">2</span>,
<span class="ident">Four</span> <span class="op">=</span> <span class="number">4</span>,
<span class="ident">Eight</span> <span class="op">=</span> <span class="number">8</span>,
<span class="ident">Sixteen</span> <span class="op">=</span> <span class="number">16</span>,
}
<span class="kw">impl</span> <span class="ident">BitDepth</span> {
<span class="doccomment">/// u8 -> Self. Temporary solution until Rust provides a canonical one.</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">from_u8</span>(<span class="ident">n</span>: <span class="ident">u8</span>) <span class="op">-</span><span class="op">></span> <span class="prelude-ty">Option</span><span class="op"><</span><span class="ident">BitDepth</span><span class="op">></span> {
<span class="kw">match</span> <span class="ident">n</span> {
<span class="number">1</span> <span class="op">=</span><span class="op">></span> <span class="prelude-val">Some</span>(<span class="ident">BitDepth</span>::<span class="ident">One</span>),
<span class="number">2</span> <span class="op">=</span><span class="op">></span> <span class="prelude-val">Some</span>(<span class="ident">BitDepth</span>::<span class="ident">Two</span>),
<span class="number">4</span> <span class="op">=</span><span class="op">></span> <span class="prelude-val">Some</span>(<span class="ident">BitDepth</span>::<span class="ident">Four</span>),
<span class="number">8</span> <span class="op">=</span><span class="op">></span> <span class="prelude-val">Some</span>(<span class="ident">BitDepth</span>::<span class="ident">Eight</span>),
<span class="number">16</span> <span class="op">=</span><span class="op">></span> <span class="prelude-val">Some</span>(<span class="ident">BitDepth</span>::<span class="ident">Sixteen</span>),
<span class="kw">_</span> <span class="op">=</span><span class="op">></span> <span class="prelude-val">None</span>
}
}
}
<span class="doccomment">/// Pixel dimensions information</span>
<span class="attribute">#[<span class="ident">derive</span>(<span class="ident">Clone</span>, <span class="ident">Copy</span>, <span class="ident">Debug</span>)]</span>
<span class="kw">pub</span> <span class="kw">struct</span> <span class="ident">PixelDimensions</span> {
<span class="doccomment">/// Pixels per unit, X axis</span>
<span class="kw">pub</span> <span class="ident">xppu</span>: <span class="ident">u32</span>,
<span class="doccomment">/// Pixels per unit, Y axis</span>
<span class="kw">pub</span> <span class="ident">yppu</span>: <span class="ident">u32</span>,
<span class="doccomment">/// Either *Meter* or *Unspecified*</span>
<span class="kw">pub</span> <span class="ident">unit</span>: <span class="ident">Unit</span>,
}
<span class="attribute">#[<span class="ident">derive</span>(<span class="ident">Debug</span>, <span class="ident">Clone</span>, <span class="ident">Copy</span>, <span class="ident">PartialEq</span>, <span class="ident">Eq</span>)]</span>
<span class="attribute">#[<span class="ident">repr</span>(<span class="ident">u8</span>)]</span>
<span class="doccomment">/// Physical unit of the pixel dimensions</span>
<span class="kw">pub</span> <span class="kw">enum</span> <span class="ident">Unit</span> {
<span class="ident">Unspecified</span> <span class="op">=</span> <span class="number">0</span>,
<span class="ident">Meter</span> <span class="op">=</span> <span class="number">1</span>,
}
<span class="kw">impl</span> <span class="ident">Unit</span> {
<span class="doccomment">/// u8 -> Self. Temporary solution until Rust provides a canonical one.</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">from_u8</span>(<span class="ident">n</span>: <span class="ident">u8</span>) <span class="op">-</span><span class="op">></span> <span class="prelude-ty">Option</span><span class="op"><</span><span class="ident">Unit</span><span class="op">></span> {
<span class="kw">match</span> <span class="ident">n</span> {
<span class="number">0</span> <span class="op">=</span><span class="op">></span> <span class="prelude-val">Some</span>(<span class="ident">Unit</span>::<span class="ident">Unspecified</span>),
<span class="number">1</span> <span class="op">=</span><span class="op">></span> <span class="prelude-val">Some</span>(<span class="ident">Unit</span>::<span class="ident">Meter</span>),
<span class="kw">_</span> <span class="op">=</span><span class="op">></span> <span class="prelude-val">None</span>
}
}
}
<span class="doccomment">/// Frame control information</span>
<span class="attribute">#[<span class="ident">derive</span>(<span class="ident">Clone</span>, <span class="ident">Debug</span>)]</span>
<span class="kw">pub</span> <span class="kw">struct</span> <span class="ident">FrameControl</span> {
<span class="doccomment">/// Sequence number of the animation chunk, starting from 0</span>
<span class="kw">pub</span> <span class="ident">sequence_number</span>: <span class="ident">u32</span>,
<span class="doccomment">/// Width of the following frame</span>
<span class="kw">pub</span> <span class="ident">width</span>: <span class="ident">u32</span>,
<span class="doccomment">/// Height of the following frame</span>
<span class="kw">pub</span> <span class="ident">height</span>: <span class="ident">u32</span>,
<span class="doccomment">/// X position at which to render the following frame</span>
<span class="kw">pub</span> <span class="ident">x_offset</span>: <span class="ident">u32</span>,
<span class="doccomment">/// Y position at which to render the following frame</span>
<span class="kw">pub</span> <span class="ident">y_offset</span>: <span class="ident">u32</span>,
<span class="doccomment">/// Frame delay fraction numerator</span>
<span class="kw">pub</span> <span class="ident">delay_num</span>: <span class="ident">u16</span>,
<span class="doccomment">/// Frame delay fraction denominator</span>
<span class="kw">pub</span> <span class="ident">delay_den</span>: <span class="ident">u16</span>,
<span class="doccomment">/// Type of frame area disposal to be done after rendering this frame</span>
<span class="kw">pub</span> <span class="ident">dispose_op</span>: <span class="ident">u8</span>,
<span class="doccomment">/// Type of frame area rendering for this frame</span>
<span class="kw">pub</span> <span class="ident">blend_op</span>: <span class="ident">u8</span>,
}
<span class="doccomment">/// Animation control information</span>
<span class="attribute">#[<span class="ident">derive</span>(<span class="ident">Clone</span>, <span class="ident">Copy</span>, <span class="ident">Debug</span>)]</span>
<span class="kw">pub</span> <span class="kw">struct</span> <span class="ident">AnimationControl</span> {
<span class="doccomment">/// Number of frames</span>
<span class="kw">pub</span> <span class="ident">num_frames</span>: <span class="ident">u32</span>,
<span class="doccomment">/// Number of times to loop this APNG. 0 indicates infinite looping.</span>
<span class="kw">pub</span> <span class="ident">num_plays</span>: <span class="ident">u32</span>,
}
<span class="attribute">#[<span class="ident">derive</span>(<span class="ident">Debug</span>, <span class="ident">Clone</span>)]</span>
<span class="kw">pub</span> <span class="kw">enum</span> <span class="ident">Compression</span> {
<span class="doccomment">/// Default level </span>
<span class="ident">Default</span>,
<span class="doccomment">/// Fast minimal compression</span>
<span class="ident">Fast</span>,
<span class="doccomment">/// Higher compression level </span>
<span class="doccomment">///</span>
<span class="doccomment">/// Best in this context isn't actually the highest possible level</span>
<span class="doccomment">/// the encoder can do, but is meant to emulate the `Best` setting in the `Flate2`</span>
<span class="doccomment">/// library.</span>
<span class="ident">Best</span>,
<span class="ident">Huffman</span>,
<span class="ident">Rle</span>,
}
<span class="doccomment">/// PNG info struct</span>
<span class="attribute">#[<span class="ident">derive</span>(<span class="ident">Debug</span>)]</span>
<span class="kw">pub</span> <span class="kw">struct</span> <span class="ident">Info</span> {
<span class="kw">pub</span> <span class="ident">width</span>: <span class="ident">u32</span>,
<span class="kw">pub</span> <span class="ident">height</span>: <span class="ident">u32</span>,
<span class="kw">pub</span> <span class="ident">bit_depth</span>: <span class="ident">BitDepth</span>,
<span class="kw">pub</span> <span class="ident">color_type</span>: <span class="ident">ColorType</span>,
<span class="kw">pub</span> <span class="ident">interlaced</span>: <span class="ident">bool</span>,
<span class="kw">pub</span> <span class="ident">trns</span>: <span class="prelude-ty">Option</span><span class="op"><</span><span class="ident">Vec</span><span class="op"><</span><span class="ident">u8</span><span class="op">></span><span class="op">></span>,
<span class="kw">pub</span> <span class="ident">pixel_dims</span>: <span class="prelude-ty">Option</span><span class="op"><</span><span class="ident">PixelDimensions</span><span class="op">></span>,
<span class="kw">pub</span> <span class="ident">palette</span>: <span class="prelude-ty">Option</span><span class="op"><</span><span class="ident">Vec</span><span class="op"><</span><span class="ident">u8</span><span class="op">></span><span class="op">></span>,
<span class="kw">pub</span> <span class="ident">frame_control</span>: <span class="prelude-ty">Option</span><span class="op"><</span><span class="ident">FrameControl</span><span class="op">></span>,
<span class="kw">pub</span> <span class="ident">animation_control</span>: <span class="prelude-ty">Option</span><span class="op"><</span><span class="ident">AnimationControl</span><span class="op">></span>,
<span class="kw">pub</span> <span class="ident">compression</span>: <span class="ident">Compression</span>,
<span class="kw">pub</span> <span class="ident">filter</span>: <span class="ident">filter</span>::<span class="ident">FilterType</span>,
}
<span class="kw">impl</span> <span class="ident">Default</span> <span class="kw">for</span> <span class="ident">Info</span> {
<span class="kw">fn</span> <span class="ident">default</span>() <span class="op">-</span><span class="op">></span> <span class="ident">Info</span> {
<span class="ident">Info</span> {
<span class="ident">width</span>: <span class="number">0</span>,
<span class="ident">height</span>: <span class="number">0</span>,
<span class="ident">bit_depth</span>: <span class="ident">BitDepth</span>::<span class="ident">Eight</span>,
<span class="ident">color_type</span>: <span class="ident">ColorType</span>::<span class="ident">Grayscale</span>,
<span class="ident">interlaced</span>: <span class="bool-val">false</span>,
<span class="ident">palette</span>: <span class="prelude-val">None</span>,
<span class="ident">trns</span>: <span class="prelude-val">None</span>,
<span class="ident">pixel_dims</span>: <span class="prelude-val">None</span>,
<span class="ident">frame_control</span>: <span class="prelude-val">None</span>,
<span class="ident">animation_control</span>: <span class="prelude-val">None</span>,
<span class="comment">// Default to `deflate::Compresion::Fast` and `filter::FilterType::Sub` </span>
<span class="comment">// to maintain backward compatible output. </span>
<span class="ident">compression</span>: <span class="ident">Compression</span>::<span class="ident">Fast</span>,
<span class="ident">filter</span>: <span class="ident">filter</span>::<span class="ident">FilterType</span>::<span class="ident">Sub</span>,
}
}
}
<span class="kw">impl</span> <span class="ident">Info</span> {
<span class="doccomment">/// Size of the image</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">size</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-</span><span class="op">></span> (<span class="ident">u32</span>, <span class="ident">u32</span>) {
(<span class="self">self</span>.<span class="ident">width</span>, <span class="self">self</span>.<span class="ident">height</span>)
}
<span class="doccomment">/// Returns true if the image is an APNG image.</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">is_animated</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-</span><span class="op">></span> <span class="ident">bool</span> {
<span class="self">self</span>.<span class="ident">frame_control</span>.<span class="ident">is_some</span>() <span class="kw-2">&</span><span class="op">&</span> <span class="self">self</span>.<span class="ident">animation_control</span>.<span class="ident">is_some</span>()
}
<span class="doccomment">/// Returns the frame control information of the image</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">animation_control</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-</span><span class="op">></span> <span class="prelude-ty">Option</span><span class="op"><</span><span class="kw-2">&</span><span class="ident">AnimationControl</span><span class="op">></span> {
<span class="self">self</span>.<span class="ident">animation_control</span>.<span class="ident">as_ref</span>()
}
<span class="doccomment">/// Returns the frame control information of the current frame</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">frame_control</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-</span><span class="op">></span> <span class="prelude-ty">Option</span><span class="op"><</span><span class="kw-2">&</span><span class="ident">FrameControl</span><span class="op">></span> {
<span class="self">self</span>.<span class="ident">frame_control</span>.<span class="ident">as_ref</span>()
}
<span class="doccomment">/// Returns the bits per pixel</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">bits_per_pixel</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-</span><span class="op">></span> <span class="ident">usize</span> {
<span class="self">self</span>.<span class="ident">color_type</span>.<span class="ident">samples</span>() <span class="op">*</span> <span class="self">self</span>.<span class="ident">bit_depth</span> <span class="kw">as</span> <span class="ident">usize</span>
}
<span class="doccomment">/// Returns the bytes per pixel</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">bytes_per_pixel</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-</span><span class="op">></span> <span class="ident">usize</span> {
<span class="self">self</span>.<span class="ident">color_type</span>.<span class="ident">samples</span>() <span class="op">*</span> ((<span class="self">self</span>.<span class="ident">bit_depth</span> <span class="kw">as</span> <span class="ident">usize</span> <span class="op">+</span> <span class="number">7</span>) <span class="op">></span><span class="op">></span> <span class="number">3</span>)
}
<span class="doccomment">/// Returns the number of bytes needed for one deinterlaced image</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">raw_bytes</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-</span><span class="op">></span> <span class="ident">usize</span> {
<span class="self">self</span>.<span class="ident">height</span> <span class="kw">as</span> <span class="ident">usize</span> <span class="op">*</span> <span class="self">self</span>.<span class="ident">raw_row_length</span>()
}
<span class="doccomment">/// Returns the number of bytes needed for one deinterlaced row </span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">raw_row_length</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-</span><span class="op">></span> <span class="ident">usize</span> {
<span class="kw">let</span> <span class="ident">bits</span> <span class="op">=</span> <span class="self">self</span>.<span class="ident">width</span> <span class="kw">as</span> <span class="ident">usize</span> <span class="op">*</span> <span class="self">self</span>.<span class="ident">color_type</span>.<span class="ident">samples</span>() <span class="op">*</span> <span class="self">self</span>.<span class="ident">bit_depth</span> <span class="kw">as</span> <span class="ident">usize</span>;
<span class="kw">let</span> <span class="ident">extra</span> <span class="op">=</span> <span class="ident">bits</span> <span class="op">%</span> <span class="number">8</span>;
<span class="ident">bits</span><span class="op">/</span><span class="number">8</span>
<span class="op">+</span> <span class="kw">match</span> <span class="ident">extra</span> { <span class="number">0</span> <span class="op">=</span><span class="op">></span> <span class="number">0</span>, <span class="kw">_</span> <span class="op">=</span><span class="op">></span> <span class="number">1</span> }
<span class="op">+</span> <span class="number">1</span> <span class="comment">// filter method</span>
}
<span class="doccomment">/// Returns the number of bytes needed for one deinterlaced row of width `width`</span>
<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">raw_row_length_from_width</span>(<span class="kw-2">&</span><span class="self">self</span>, <span class="ident">width</span>: <span class="ident">u32</span>) <span class="op">-</span><span class="op">></span> <span class="ident">usize</span> {
<span class="kw">let</span> <span class="ident">bits</span> <span class="op">=</span> <span class="ident">width</span> <span class="kw">as</span> <span class="ident">usize</span> <span class="op">*</span> <span class="self">self</span>.<span class="ident">color_type</span>.<span class="ident">samples</span>() <span class="op">*</span> <span class="self">self</span>.<span class="ident">bit_depth</span> <span class="kw">as</span> <span class="ident">usize</span>;
<span class="kw">let</span> <span class="ident">extra</span> <span class="op">=</span> <span class="ident">bits</span> <span class="op">%</span> <span class="number">8</span>;
<span class="ident">bits</span><span class="op">/</span><span class="number">8</span>
<span class="op">+</span> <span class="kw">match</span> <span class="ident">extra</span> { <span class="number">0</span> <span class="op">=</span><span class="op">></span> <span class="number">0</span>, <span class="kw">_</span> <span class="op">=</span><span class="op">></span> <span class="number">1</span> }
<span class="op">+</span> <span class="number">1</span> <span class="comment">// filter method</span>
}
}
<span class="macro">bitflags</span><span class="macro">!</span> {
<span class="doccomment">/// # Output transformations</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Only `IDENTITY` and `TRANSFORM_EXPAND | TRANSFORM_STRIP_ALPHA` can be used at the moment.</span>
<span class="kw">pub</span> <span class="kw">struct</span> <span class="ident">Transformations</span>: <span class="ident">u32</span> {
<span class="doccomment">/// No transformation</span>
<span class="kw">const</span> <span class="ident">IDENTITY</span> <span class="op">=</span> <span class="number">0x0000</span>; <span class="comment">// read and write */</span>
<span class="doccomment">/// Strip 16-bit samples to 8 bits</span>
<span class="kw">const</span> <span class="ident">STRIP_16</span> <span class="op">=</span> <span class="number">0x0001</span>; <span class="comment">// read only */</span>
<span class="doccomment">/// Discard the alpha channel</span>
<span class="kw">const</span> <span class="ident">STRIP_ALPHA</span> <span class="op">=</span> <span class="number">0x0002</span>; <span class="comment">// read only */</span>
<span class="doccomment">/// Expand 1; 2 and 4-bit samples to bytes</span>
<span class="kw">const</span> <span class="ident">PACKING</span> <span class="op">=</span> <span class="number">0x0004</span>; <span class="comment">// read and write */</span>
<span class="doccomment">/// Change order of packed pixels to LSB first</span>
<span class="kw">const</span> <span class="ident">PACKSWAP</span> <span class="op">=</span> <span class="number">0x0008</span>; <span class="comment">// read and write */</span>
<span class="doccomment">/// Expand paletted images to RGB; expand grayscale images of</span>
<span class="doccomment">/// less than 8-bit depth to 8-bit depth; and expand tRNS chunks</span>
<span class="doccomment">/// to alpha channels.</span>
<span class="kw">const</span> <span class="ident">EXPAND</span> <span class="op">=</span> <span class="number">0x0010</span>; <span class="comment">// read only */</span>
<span class="doccomment">/// Invert monochrome images</span>
<span class="kw">const</span> <span class="ident">INVERT_MONO</span> <span class="op">=</span> <span class="number">0x0020</span>; <span class="comment">// read and write */</span>
<span class="doccomment">/// Normalize pixels to the sBIT depth</span>
<span class="kw">const</span> <span class="ident">SHIFT</span> <span class="op">=</span> <span class="number">0x0040</span>; <span class="comment">// read and write */</span>
<span class="doccomment">/// Flip RGB to BGR; RGBA to BGRA</span>
<span class="kw">const</span> <span class="ident">BGR</span> <span class="op">=</span> <span class="number">0x0080</span>; <span class="comment">// read and write */</span>
<span class="doccomment">/// Flip RGBA to ARGB or GA to AG</span>
<span class="kw">const</span> <span class="ident">SWAP_ALPHA</span> <span class="op">=</span> <span class="number">0x0100</span>; <span class="comment">// read and write */</span>
<span class="doccomment">/// Byte-swap 16-bit samples</span>
<span class="kw">const</span> <span class="ident">SWAP_ENDIAN</span> <span class="op">=</span> <span class="number">0x0200</span>; <span class="comment">// read and write */</span>
<span class="doccomment">/// Change alpha from opacity to transparency</span>
<span class="kw">const</span> <span class="ident">INVERT_ALPHA</span> <span class="op">=</span> <span class="number">0x0400</span>; <span class="comment">// read and write */</span>
<span class="kw">const</span> <span class="ident">STRIP_FILLER</span> <span class="op">=</span> <span class="number">0x0800</span>; <span class="comment">// write only */</span>
<span class="kw">const</span> <span class="ident">STRIP_FILLER_BEFORE</span> <span class="op">=</span> <span class="number">0x0800</span>; <span class="comment">// write only</span>
<span class="kw">const</span> <span class="ident">STRIP_FILLER_AFTER</span> <span class="op">=</span> <span class="number">0x1000</span>; <span class="comment">// write only */</span>
<span class="kw">const</span> <span class="ident">GRAY_TO_RGB</span> <span class="op">=</span> <span class="number">0x2000</span>; <span class="comment">// read only */</span>
<span class="kw">const</span> <span class="ident">EXPAND_16</span> <span class="op">=</span> <span class="number">0x4000</span>; <span class="comment">// read only */</span>
<span class="kw">const</span> <span class="ident">SCALE_16</span> <span class="op">=</span> <span class="number">0x8000</span>; <span class="comment">// read only */</span>
}
}
<span class="doccomment">/// Mod to encapsulate the converters depending on the `deflate` crate.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Since this only contains trait impls, there is no need to make this public, they are simply</span>
<span class="doccomment">/// available when the mod is compiled as well.</span>
<span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"png-encoding"</span>)]</span>
<span class="kw">mod</span> <span class="ident">deflate_convert</span> {
<span class="kw">extern</span> <span class="kw">crate</span> <span class="ident">deflate</span>;
<span class="kw">use</span> <span class="kw">super</span>::<span class="ident">Compression</span>;
<span class="kw">impl</span> <span class="ident">From</span><span class="op"><</span><span class="ident">deflate</span>::<span class="ident">Compression</span><span class="op">></span> <span class="kw">for</span> <span class="ident">Compression</span> {
<span class="kw">fn</span> <span class="ident">from</span>(<span class="ident">c</span>: <span class="ident">deflate</span>::<span class="ident">Compression</span>) <span class="op">-</span><span class="op">></span> <span class="self">Self</span> {
<span class="kw">match</span> <span class="ident">c</span> {
<span class="ident">deflate</span>::<span class="ident">Compression</span>::<span class="ident">Default</span> <span class="op">=</span><span class="op">></span> <span class="ident">Compression</span>::<span class="ident">Default</span>,
<span class="ident">deflate</span>::<span class="ident">Compression</span>::<span class="ident">Fast</span> <span class="op">=</span><span class="op">></span> <span class="ident">Compression</span>::<span class="ident">Fast</span>,
<span class="ident">deflate</span>::<span class="ident">Compression</span>::<span class="ident">Best</span> <span class="op">=</span><span class="op">></span> <span class="ident">Compression</span>::<span class="ident">Best</span>,
}
}
}
<span class="kw">impl</span> <span class="ident">From</span><span class="op"><</span><span class="ident">Compression</span><span class="op">></span> <span class="kw">for</span> <span class="ident">deflate</span>::<span class="ident">CompressionOptions</span> {
<span class="kw">fn</span> <span class="ident">from</span>(<span class="ident">c</span>: <span class="ident">Compression</span>) <span class="op">-</span><span class="op">></span> <span class="self">Self</span> {
<span class="kw">match</span> <span class="ident">c</span> {
<span class="ident">Compression</span>::<span class="ident">Default</span> <span class="op">=</span><span class="op">></span> <span class="ident">deflate</span>::<span class="ident">CompressionOptions</span>::<span class="ident">default</span>(),
<span class="ident">Compression</span>::<span class="ident">Fast</span> <span class="op">=</span><span class="op">></span> <span class="ident">deflate</span>::<span class="ident">CompressionOptions</span>::<span class="ident">fast</span>(),
<span class="ident">Compression</span>::<span class="ident">Best</span> <span class="op">=</span><span class="op">></span> <span class="ident">deflate</span>::<span class="ident">CompressionOptions</span>::<span class="ident">high</span>(),
<span class="ident">Compression</span>::<span class="ident">Huffman</span> <span class="op">=</span><span class="op">></span> <span class="ident">deflate</span>::<span class="ident">CompressionOptions</span>::<span class="ident">huffman_only</span>(),
<span class="ident">Compression</span>::<span class="ident">Rle</span> <span class="op">=</span><span class="op">></span> <span class="ident">deflate</span>::<span class="ident">CompressionOptions</span>::<span class="ident">rle</span>(),
}
}
}
}
</pre></div>
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