diff options
Diffstat (limited to 'src/image.rs')
| -rw-r--r-- | src/image.rs | 184 |
1 files changed, 118 insertions, 66 deletions
diff --git a/src/image.rs b/src/image.rs index db10a162..717b1a93 100644 --- a/src/image.rs +++ b/src/image.rs @@ -2,6 +2,7 @@ use std::io; +use crate::diag::StrResult; use crate::util::Buffer; /// A raster or vector image. @@ -19,61 +20,26 @@ pub struct Image { height: u32, } -/// A decoded image. -pub enum DecodedImage { - /// A pixel raster format, like PNG or JPEG. - Raster(image::DynamicImage), - /// An SVG vector graphic. - Svg(usvg::Tree), -} - -/// A raster or vector image format. -#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)] -pub enum ImageFormat { - /// Raster format for illustrations and transparent graphics. - Png, - /// Lossy raster format suitable for photos. - Jpg, - /// Raster format that is typically used for short animated clips. - Gif, - /// The vector graphics format of the web. - Svg, -} - impl Image { - /// Create an image from a raw buffer and a file extension. + /// Create an image from a buffer and a format. /// - /// The file extension is used to determine the format. - pub fn new(data: Buffer, ext: &str) -> io::Result<Self> { - let format = match ext { - "svg" | "svgz" => ImageFormat::Svg, - "png" => ImageFormat::Png, - "jpg" | "jpeg" => ImageFormat::Jpg, - "gif" => ImageFormat::Gif, - _ => { - return Err(io::Error::new( - io::ErrorKind::InvalidData, - "unknown image format", - )); - } - }; - + /// Extracts the width and height. + pub fn new(data: Buffer, format: ImageFormat) -> StrResult<Self> { let (width, height) = match format { - ImageFormat::Svg => { + ImageFormat::Vector(VectorFormat::Svg) => { let opts = usvg::Options::default(); - let tree = - usvg::Tree::from_data(&data, &opts.to_ref()).map_err(invalid)?; + let tree = usvg::Tree::from_data(&data, &opts.to_ref()) + .map_err(format_usvg_error)?; let size = tree.svg_node().size; let width = size.width().ceil() as u32; let height = size.height().ceil() as u32; (width, height) } - _ => { + ImageFormat::Raster(format) => { let cursor = io::Cursor::new(&data); - let format = convert_format(format); - let reader = image::io::Reader::with_format(cursor, format); - reader.into_dimensions().map_err(invalid)? + let reader = image::io::Reader::with_format(cursor, format.into()); + reader.into_dimensions().map_err(format_image_error)? } }; @@ -101,39 +67,125 @@ impl Image { } /// Decode the image. - pub fn decode(&self) -> io::Result<DecodedImage> { + pub fn decode(&self) -> StrResult<DecodedImage> { Ok(match self.format { - ImageFormat::Svg => { + ImageFormat::Vector(VectorFormat::Svg) => { let opts = usvg::Options::default(); - let tree = - usvg::Tree::from_data(&self.data, &opts.to_ref()).map_err(invalid)?; + let tree = usvg::Tree::from_data(&self.data, &opts.to_ref()) + .map_err(format_usvg_error)?; DecodedImage::Svg(tree) } - _ => { + ImageFormat::Raster(format) => { let cursor = io::Cursor::new(&self.data); - let format = convert_format(self.format); - let reader = image::io::Reader::with_format(cursor, format); - let dynamic = reader.decode().map_err(invalid)?; - DecodedImage::Raster(dynamic) + let reader = image::io::Reader::with_format(cursor, format.into()); + let dynamic = reader.decode().map_err(format_image_error)?; + DecodedImage::Raster(dynamic, format) } }) } } -/// Convert a raster image format to the image crate's format. -fn convert_format(format: ImageFormat) -> image::ImageFormat { - match format { - ImageFormat::Png => image::ImageFormat::Png, - ImageFormat::Jpg => image::ImageFormat::Jpeg, - ImageFormat::Gif => image::ImageFormat::Gif, - ImageFormat::Svg => panic!("must be a raster format"), +/// A raster or vector image format. +#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)] +pub enum ImageFormat { + /// A raster graphics format. + Raster(RasterFormat), + /// A vector graphics format. + Vector(VectorFormat), +} + +/// A raster graphics format. +#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)] +pub enum RasterFormat { + /// Raster format for illustrations and transparent graphics. + Png, + /// Lossy raster format suitable for photos. + Jpg, + /// Raster format that is typically used for short animated clips. + Gif, +} + +/// A vector graphics format. +#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)] +pub enum VectorFormat { + /// The vector graphics format of the web. + Svg, +} + +impl From<RasterFormat> for image::ImageFormat { + fn from(format: RasterFormat) -> Self { + match format { + RasterFormat::Png => image::ImageFormat::Png, + RasterFormat::Jpg => image::ImageFormat::Jpeg, + RasterFormat::Gif => image::ImageFormat::Gif, + } } } -/// Turn any error into an I/O error. -fn invalid<E>(error: E) -> io::Error -where - E: std::error::Error + Send + Sync + 'static, -{ - io::Error::new(io::ErrorKind::InvalidData, error) +impl From<ttf_parser::RasterImageFormat> for RasterFormat { + fn from(format: ttf_parser::RasterImageFormat) -> Self { + match format { + ttf_parser::RasterImageFormat::PNG => RasterFormat::Png, + } + } +} + +impl From<ttf_parser::RasterImageFormat> for ImageFormat { + fn from(format: ttf_parser::RasterImageFormat) -> Self { + Self::Raster(format.into()) + } +} + +/// A decoded image. +pub enum DecodedImage { + /// A decoded pixel raster. + Raster(image::DynamicImage, RasterFormat), + /// An decoded SVG tree. + Svg(usvg::Tree), +} + +/// Format the user-facing raster graphic decoding error message. +fn format_image_error(error: image::ImageError) -> String { + match error { + image::ImageError::Limits(_) => "file is too large".into(), + _ => "failed to decode image".into(), + } +} + +/// Format the user-facing SVG decoding error message. +fn format_usvg_error(error: usvg::Error) -> String { + match error { + usvg::Error::NotAnUtf8Str => "file is not valid utf-8".into(), + usvg::Error::MalformedGZip => "file is not compressed correctly".into(), + usvg::Error::ElementsLimitReached => "file is too large".into(), + usvg::Error::InvalidSize => { + "failed to parse svg: width, height, or viewbox is invalid".into() + } + usvg::Error::ParsingFailed(error) => match error { + roxmltree::Error::UnexpectedCloseTag { expected, actual, pos } => { + format!( + "failed to parse svg: found closing tag '{actual}' \ + instead of '{expected}' in line {}", + pos.row + ) + } + roxmltree::Error::UnknownEntityReference(entity, pos) => { + format!( + "failed to parse svg: unknown entity '{entity}' in line {}", + pos.row + ) + } + roxmltree::Error::DuplicatedAttribute(attr, pos) => { + format!( + "failed to parse svg: duplicate attribute '{attr}' in line {}", + pos.row + ) + } + roxmltree::Error::NoRootNode => { + "failed to parse svg: missing root node".into() + } + roxmltree::Error::SizeLimit => "file is too large".into(), + _ => "failed to parse svg".into(), + }, + } } |