Stub out reduce operation

src/cli_args.rs

@@ -2,7 +2,7 @@ use clap::Parser;
 use serde::{Deserialize, Serialize};
 
 // use crate::commands::{calculate_mapping, execute_pipeline, extrude, flip, palette, remap_image, rescale, rotate, write_palette, FlipDirection, RotateDegree, Rotate};
-use crate::commands::{Extrude, Flip, Palette, Pipeline, Remap, Rotate, Scale};
+use crate::commands::{Extrude, Flip, Palette, Pipeline, Reduce, Remap, Rotate, Scale};
 
 use crate::load_image;
 
@@ -33,9 +33,12 @@ pub enum Args {
 	#[clap(name = "remap")]
 	#[serde(alias = "remap")]
 	Remap(Remap),
-	#[clap(name = "remap")]
-	#[serde(alias = "remap")]
+	#[clap(name = "pipeline")]
+	#[serde(alias = "pipeline")]
 	Pipeline(Pipeline),
+	#[clap(name = "reduce")]
+	#[serde(alias = "reduce")]
+	Reduce(Reduce),
 }
 
 impl Args {
@@ -85,6 +88,15 @@ impl Args {
 
 				output.save(&remap.output).map_err(anyhow::Error::from)
 			}
+			Args::Reduce(reduce) => {
+				if let Some(amount) = reduce.colours {
+					log::info!("Num cols {}", amount);
+				} else {
+					log::info!("No Limit");
+				}
+
+				Ok(())
+			}
 			Args::Pipeline(pipeline) => pipeline.execute(),
 		}
 	}

src/commands/mod.rs

@@ -5,6 +5,7 @@ mod pipeline;
 mod remap;
 mod rotate;
 mod scale;
+mod reduce;
 
 pub use extrude::Extrude;
 pub use flip::Flip;
@@ -13,3 +14,4 @@ pub use pipeline::Pipeline;
 pub use remap::Remap;
 pub use rotate::Rotate;
 pub use scale::Scale;
+pub use reduce::Reduce;

src/commands/reduce.rs

+use crate::commands::palette::ColourMapping;
+use crate::commands::Palette;
+use crate::utils::{RgbaOutputFormat, TypedOutputFormat};
+use anyhow::Error;
+use clap::Parser;
+use image::{GenericImage, ImageBuffer, Rgba, RgbaImage};
+use serde::{Deserialize, Serialize};
+use std::collections::HashMap;
+
+/// Limit the number of colours by quantity or threshold
+#[derive(Debug, Clone, Parser, Serialize, Deserialize)]
+#[clap(author, version = "0.3.0")]
+pub struct Reduce {
+	/// The path to the image file
+	#[serde(default)]
+	pub input: String,
+	/// The path to write the recoloured image
+	#[serde(default)]
+	pub output: String,
+
+	/// The number of colours to use for quantizing
+	#[clap(short, long)]
+	pub colours: Option<u32>,
+	/// The colour difference threshold to limit colour reduction
+	#[clap(short, long)]
+	pub threshold: Option<f32>,
+}
+
+impl Reduce {
+	pub fn run<T: GenericImage>(&self, mut image: &T) -> anyhow::Result<RgbaOutputFormat> {
+		Err(Error::msg("Reduce is not implemented"))
+
+		// TODO: Reduce impl
+		// let mut palette = Palette::extract_from(image)?;
+		//
+		// let similarity = HashMap::with_capacity(palette.len());
+		// let mapping: ColourMapping = ColourMapping::new();
+		//
+		// while !palette.is_empty() {
+		// 	let next = palette.pop();
+		// }
+		//
+		// Ok(RgbaImage::from_fn(image.width(), image.height(), |x, y| {
+		// 	Rgba::from([0, 0, 0, 0])
+		// }))
+	}
+}