Add gif components

17 files changed, 382 insertions, 417 deletions

diff --git a/Cargo.toml b/Cargo.toml
index 2121b44..f4ffb22 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -7,4 +7,12 @@ license = "CC0-1.0"
 description = "Gif encoding and decoding with fine control"
 repository = "https://github.com/genuinebyte/gifed"
 
+[dev-dependencies]
+criterion = "0.3"
+rand = "0.7.3"
+
 [dependencies]
+
+[[bench]]
+name = "lzw_encode"
+harness = false
\ No newline at end of file
diff --git a/README.md b/README.md
index e6bb540..d48b26e 100644
--- a/README.md
+++ b/README.md
@@ -12,7 +12,9 @@ always will be, one of the main goals of this crate.
 - [ ] Automatically select the lowest version possible when writing
 - [ ] Read GIF87a
 - [ ] Read GIF89a
-- [ ] Feature to allow using [weezl][weezl-crates] for LZW compression instead of the built-in
-- [ ] Well written and easy to understand docs! (Can never truly be finished, but "good enough")
+- [ ] Feature to allow using the [weezl][weezl-crates] crate for LZW compression instead of the built-in
+- [ ] Feature to allow using the [rgb][rgb-crates] crate for the color type.
+- [ ] Well written and easy to understand docs! `bitvec` quality, but who can match that?
 
-[weezl-crates]: https://crates.io/crates/weezl
\ No newline at end of file
+[weezl-crates]: https://crates.io/crates/weezl
+[rgb-crates]: https://crates.io/crates/rgb
\ No newline at end of file
diff --git a/benches/lzw_encode.rs b/benches/lzw_encode.rs
new file mode 100644
index 0000000..33440b2
--- /dev/null
+++ b/benches/lzw_encode.rs
@@ -0,0 +1,13 @@
+use criterion::{black_box, criterion_group, criterion_main, Criterion};
+use rand::{thread_rng, Rng};
+use gifed::LZW;
+
+pub fn criterion_benchmark(c: &mut Criterion) {
+	let mut random = [0u8; 255];
+	thread_rng().fill(&mut random[..]);
+
+    c.bench_function("lzw encode 255bytes", |b| b.iter(|| LZW::encode(8, black_box(&random))));
+}
+
+criterion_group!(benches, criterion_benchmark);
+criterion_main!(benches);
\ No newline at end of file
diff --git a/src/common/mod.rs b/src/components/color.rs
index 1080e29..dc134ef 100644
--- a/src/common/mod.rs
+++ b/src/components/color.rs
@@ -1,8 +1,3 @@
-pub enum Version {
-	Gif87a,
-	Gif89a
-}
-
 pub struct Color {
 	pub r: u8,
 	pub g: u8,
@@ -11,10 +6,6 @@ pub struct Color {
 
 impl Color {
 	pub fn new(r: u8, g: u8, b: u8) -> Self {
-		Self {
-			r,
-			g,
-			b
-		}
+		Self { r, g, b }
 	}
 }
\ No newline at end of file
diff --git a/src/components/colortable.rs b/src/components/colortable.rs
new file mode 100644
index 0000000..f756169
--- /dev/null
+++ b/src/components/colortable.rs
@@ -0,0 +1,67 @@
+use std::ops::Deref;
+pub use super::Color;
+
+pub struct ColorTable {
+	table: Vec<Color>
+}
+
+impl ColorTable {
+	pub fn new() -> Self {
+		Self {
+			table: vec![]
+		}
+	}
+
+	/// Returns the number of colors in the color table as used by the packed
+	/// fields in the Logical Screen Descriptor and Image Descriptor. You can
+	/// get the actual size with the [`len`](struct.ColorTable.html#method.len) method.
+	pub fn packed_len(&self) -> u8 {
+		((self.table.len() as f32).log2().ceil() - 1f32) as u8
+	}
+
+	/// Returns the number of items in the table
+	pub fn len(&self) -> usize {
+		self.table.len()
+	}
+
+	/// Pushes a color on to the end of the table
+	pub fn push(&mut self, color: Color) {
+		self.table.push(color);
+	}
+}
+
+impl Deref for ColorTable {
+	type Target = [Color];
+
+	fn deref(&self) -> &Self::Target {
+		&self.table
+	}
+}
+
+impl From<Vec<Color>> for ColorTable {
+	fn from(table: Vec<Color>) -> Self{
+		ColorTable {
+			table
+		}
+	}
+}
+
+impl From<&ColorTable> for Box<[u8]> {
+	fn from(table: &ColorTable) -> Self {
+		let mut vec = vec![];
+
+		for color in table.iter() {
+			vec.extend_from_slice(&[color.r, color.g, color.b]);
+		}
+
+		let packed_len = 2u8.pow(table.packed_len() as u32 + 1);
+		let padding = (packed_len as usize - table.len()) * 3;
+		if padding > 0 {
+			vec.extend_from_slice(&vec![0; padding]);
+		}
+
+		vec.into_boxed_slice()
+	}
+}
+
+//TODO: TryFrom Vec<u8> (must be multiple of 3 len) and From Vec<Color>
\ No newline at end of file
diff --git a/src/components/gif.rs b/src/components/gif.rs
new file mode 100644
index 0000000..2709fe8
--- /dev/null
+++ b/src/components/gif.rs
@@ -0,0 +1,82 @@
+use super::{ColorTable, Image, LogicalScreenDescriptor, Version};
+
+pub struct Gif {
+	pub header: Version,
+	pub logical_screen_descriptor: LogicalScreenDescriptor,
+	pub global_color_table: Option<ColorTable>,
+	pub images: Vec<Image>
+	// Trailer at the end of this struct is 0x3B //
+}
+
+impl Gif {
+	pub fn to_vec(&self) -> Vec<u8> {
+		let mut out = vec![];
+
+		out.extend_from_slice((&self.header).into());
+		
+		let mut boxed: Box<[u8]> = (&self.logical_screen_descriptor).into();
+		out.extend_from_slice(&*boxed);
+
+		// While we output the color table, grab it's length to use when
+		// outputting the image, or 0 if we don't have a GCT
+		let mcs = if let Some(gct) = &self.global_color_table {
+			boxed = gct.into();
+			out.extend_from_slice(&*boxed);
+
+			gct.packed_len()
+		} else {
+			0
+		};
+
+		for image in self.images.iter() {
+			boxed = image.as_boxed_slice(mcs);
+			out.extend_from_slice(&*boxed);
+		}
+
+		// Write Trailer
+		out.push(0x3B);
+
+		out
+	}
+}
+
+#[cfg(test)]
+pub mod gif {
+	use crate::Color;
+	use crate::writer::{GifBuilder, ImageBuilder};
+	use super::*;
+
+	#[test]
+	fn to_vec() {
+		let gct = vec![
+			Color::new(1, 2, 3), Color::new(253, 254, 255)
+		];
+		let colortable = vec![
+			Color::new(0, 0, 0), Color::new(128, 0, 255)
+		];
+		let indicies = vec![0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 0, 0];
+
+		let expected_out = vec![
+			0x47, 0x49, 0x46, 0x38, 0x37, 0x61, // Version - GIF87a
+			0x04, 0x00, 0x04, 0x00, 0b1000_0000, 0x00, 0x00, // Logical Screen Descriptor
+			1, 2, 3, 253, 254, 255, // Global Color Table
+			0x2C, 0x00, 0x00, 0x00, 0x00, 0x04, 0x00, 0x04, 0x00, 0b1000_0000, // Image Descriptor 1
+			0, 0, 0, 128, 0, 255, // Color Table
+			0x02, 0x05, 0x84, 0x1D, 0x81, 0x7A, 0x50, 0x00, // Image Data 1
+			0x2C, 0x00, 0x00, 0x00, 0x00, 0x04, 0x00, 0x04, 0x00, 0b0000_0000, // Image Descriptor 2
+			0x02, 0x05, 0x84, 0x1D, 0x81, 0x7A, 0x50, 0x00, // Image Data 2
+			0x3B // Trailer
+		];
+
+		let actual_out = GifBuilder::new(Version::Gif87a, 4, 4)
+			.global_color_table(gct.into())
+			.image(ImageBuilder::new(4, 4)
+				.color_table(colortable.into())
+				.indicies(indicies.clone())
+			).image(ImageBuilder::new(4, 4)
+				.indicies(indicies)
+			).build().to_vec();
+
+		assert_eq!(actual_out, expected_out);
+	}
+}
\ No newline at end of file
diff --git a/src/components/image.rs b/src/components/image.rs
new file mode 100644
index 0000000..07f9555
--- /dev/null
+++ b/src/components/image.rs
@@ -0,0 +1,47 @@
+use crate::LZW;
+use super::{ColorTable, ImageDescriptor};
+
+pub struct Image {
+	pub image_descriptor: ImageDescriptor,
+	pub local_color_table: Option<ColorTable>,
+	pub indicies: Vec<u8>
+}
+
+impl Image {
+	pub fn as_boxed_slice(&self, minimum_code_size: u8) -> Box<[u8]> {
+		let mut out = vec![];
+
+		let mut boxed: Box<[u8]> = (&self.image_descriptor).into();
+		out.extend_from_slice(&*boxed);
+
+		// Table based image data //
+
+		// Get the mcs while we write out the color table
+		let mut mcs = if let Some(lct) = &self.local_color_table {
+			boxed = lct.into();
+			out.extend_from_slice(&*boxed);
+
+			lct.packed_len()
+		} else {
+			minimum_code_size
+		};
+
+		if mcs < 2 {
+			mcs = 2; // Must be true: 0 <= mcs <= 8
+		}
+
+		// First write out the MCS
+		out.push(mcs);
+
+		let compressed = LZW::encode(mcs, &self.indicies);
+		
+		for chunk in compressed.chunks(255) {
+			out.push(chunk.len() as u8);
+			out.extend_from_slice(chunk);
+		}
+		// Data block length 0 to indicate an end
+		out.push(0x00);
+
+		out.into_boxed_slice()
+	}
+}
\ No newline at end of file
diff --git a/src/components/imagedescriptor.rs b/src/components/imagedescriptor.rs
new file mode 100644
index 0000000..c911baa
--- /dev/null
+++ b/src/components/imagedescriptor.rs
@@ -0,0 +1,45 @@
+pub struct ImageDescriptor {
+	// Image Seperator 0x2C is the first byte //
+	pub left: u16,
+	pub top: u16,
+	pub width: u16,
+	pub height: u16,
+	pub packed: u8
+}
+
+impl ImageDescriptor {
+	pub fn color_table_present(&mut self, is_present: bool) {
+		if is_present {
+			self.packed |= 0b1000_0000;
+		} else {
+			self.packed &= 0b0111_1111;
+		}
+	}
+
+	pub fn color_table_size(&mut self, size: u8) {
+		// GCT size is calulated by raising two to this number plus one,
+		// so we have to work backwards.
+		let size = (size as f32).log2().ceil() - 1f32;
+		self.packed |= size as u8;
+	}
+
+	//TODO: Setter for sort flag in packed field
+	//TODO: Setter for interlace flag in packed field
+}
+
+impl From<&ImageDescriptor> for Box<[u8]> {
+	fn from(desc: &ImageDescriptor) -> Self {
+		let mut vec = vec![];
+
+		vec.push(0x2C); // Image Seperator
+		vec.extend_from_slice(&desc.left.to_le_bytes());
+		vec.extend_from_slice(&desc.top.to_le_bytes());
+		vec.extend_from_slice(&desc.width.to_le_bytes());
+		vec.extend_from_slice(&desc.height.to_le_bytes());
+		vec.push(desc.packed);
+
+		vec.into_boxed_slice()
+	}
+}
+
+//TODO: Impl to allow changing the packed field easier
\ No newline at end of file
diff --git a/src/components/logicalscreendescriptor.rs b/src/components/logicalscreendescriptor.rs
new file mode 100644
index 0000000..b20c9d5
--- /dev/null
+++ b/src/components/logicalscreendescriptor.rs
@@ -0,0 +1,40 @@
+pub struct LogicalScreenDescriptor {
+	pub width: u16,
+	pub height: u16,
+	pub packed: u8,
+	pub background_color_index: u8,
+	pub pixel_aspect_ratio: u8
+}
+
+impl LogicalScreenDescriptor {
+	pub fn color_table_present(&mut self, is_present: bool) {
+		if is_present {
+			self.packed |= 0b1000_0000;
+		} else {
+			self.packed &= 0b0111_1111;
+		}
+	}
+
+	pub fn color_table_size(&mut self, size: u8) {
+		// GCT size is calulated by raising two to this number plus one,
+		// so we have to work backwards.
+		let size = (size as f32).log2().ceil() - 1f32;
+		self.packed |= size as u8;
+	}
+
+	//TODO: Setter for sort flag in packed field
+	//TODO: Setter for color resolution in packed field
+}
+
+impl From<&LogicalScreenDescriptor> for Box<[u8]> {
+	fn from(lsd: &LogicalScreenDescriptor) -> Self {
+		let mut vec = vec![];
+		vec.extend_from_slice(&lsd.width.to_le_bytes());
+		vec.extend_from_slice(&lsd.height.to_le_bytes());
+		vec.push(lsd.packed);
+		vec.push(lsd.background_color_index);
+		vec.push(lsd.pixel_aspect_ratio);
+
+		vec.into_boxed_slice()
+	}
+}
\ No newline at end of file
diff --git a/src/components/mod.rs b/src/components/mod.rs
new file mode 100644
index 0000000..1650d36
--- /dev/null
+++ b/src/components/mod.rs
@@ -0,0 +1,15 @@
+mod color;
+mod colortable;
+mod gif;
+mod image;
+mod imagedescriptor;
+mod logicalscreendescriptor;
+mod version;
+
+pub use color::Color;
+pub use colortable::ColorTable;
+pub use gif::Gif;
+pub use image::Image;
+pub use imagedescriptor::ImageDescriptor;
+pub use logicalscreendescriptor::LogicalScreenDescriptor;
+pub use version::Version;
\ No newline at end of file
diff --git a/src/components/version.rs b/src/components/version.rs
new file mode 100644
index 0000000..a5d688d
--- /dev/null
+++ b/src/components/version.rs
@@ -0,0 +1,13 @@
+pub enum Version {
+	Gif87a,
+	Gif89a
+}
+
+impl From<&Version> for &[u8] {
+	fn from(version: &Version) -> Self {
+		match version {
+			Version::Gif87a => b"GIF87a",
+			Version::Gif89a => b"GIF89a"
+		}
+	}
+}
\ No newline at end of file
diff --git a/src/lib.rs b/src/lib.rs
index 187decb..6eb07d6 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,5 +1,6 @@
-mod common;
-mod writer;
+mod components;
+mod lzw;
+pub mod writer;
 
-pub use common::Version;
-pub use writer::GifBuilder;
\ No newline at end of file
+pub use components::*;
+pub use lzw::LZW;
\ No newline at end of file
diff --git a/src/writer/lzw.rs b/src/lzw.rs
index 1970617..1970617 100644
--- a/src/writer/lzw.rs
+++ b/src/lzw.rs
diff --git a/src/writer/gifbuilder.rs b/src/writer/gifbuilder.rs
index ff98ba7..6ae55d5 100644
--- a/src/writer/gifbuilder.rs
+++ b/src/writer/gifbuilder.rs
@@ -1,12 +1,11 @@
-use crate::common::{Color, Version};
-use super::OutVec;
+use crate::components::{ColorTable, Gif, LogicalScreenDescriptor, Version};
 use super::ImageBuilder;
 
 pub struct GifBuilder {
 	version: Version,
 	width: u16,
 	height: u16,
-	global_color_table: Option<Vec<Color>>,
+	global_color_table: Option<ColorTable>,
 	background_color_index: u8,
 	imagebuilders: Vec<ImageBuilder>
 }
@@ -23,13 +22,8 @@ impl GifBuilder {
 		}
 	}
 
-	pub fn global_color_table(mut self, vec: Vec<Color>) -> Self {
-		if vec.len() == 0 || vec.len() > 256 {
-			//TODO: Throw error instead of panic
-			panic!("GCT has to be less than or 256 colors in size, and at least one");
-		}
-
-		self.global_color_table = Some(vec);
+	pub fn global_color_table(mut self, table: ColorTable) -> Self {
+		self.global_color_table = Some(table);
 
 		self
 	}
@@ -49,190 +43,30 @@ impl GifBuilder {
 		self
 	}
 
-	pub fn write_to_vec(&self) -> Vec<u8> {
-		let mut out = OutVec::new();
-
-		self
-			.write_header(&mut out)
-			.write_logical_screen_descriptor(&mut out)
-			.write_global_color_table(&mut out)
-			.write_images(&mut out)
-			.write_trailer(&mut out);
-
-		out.vec()
-	}
-
-	fn write_header(&self, out: &mut OutVec) -> &Self {
-		out.push_slice(b"GIF");
-
-		//TODO: Automatically detect version
-		match self.version {
-			Version::Gif87a => out.push_slice(b"87a"),
-			Version::Gif89a => out.push_slice(b"89a")
+	pub fn build(self) -> Gif {
+		let mut lsd = LogicalScreenDescriptor {
+			width: self.width,
+			height: self.height,
+			packed: 0, // Set later
+			background_color_index: self.background_color_index,
+			pixel_aspect_ratio: 0 //TODO: Allow configuring
 		};
 
-		self
-	}
-
-	fn write_logical_screen_descriptor(&self, out: &mut OutVec) -> &Self {
-		out.push_u16(self.width).push_u16(self.height);
-
-		let mut packed: u8 = 0;
-
 		if let Some(gct) = &self.global_color_table {
-			packed |= 0b1000_0000; // Set the GCT flag
-
-			// GCT size is calulated by raising two to this number plus one,
-			// so we have to work backwards.
-			let size = (gct.len() as f32).log2().ceil() - 1f32;
-			
-			packed |= size as u8;
+			lsd.color_table_present(true);
+			lsd.color_table_size(gct.len() as u8);
 		}
-		//TODO: Color Resolution and Sort Flag fields in packed.
-		out.push_u8(packed);
-
-		out.push_u8(self.background_color_index)
-			.push_u8(0x00); //TOOD: Allow setting pixel aspect ratio
 
-		self
-	}
-
-	fn write_global_color_table(&self, out: &mut OutVec) -> &Self {
-		if let Some(gct) = &self.global_color_table {
-			out.push_colors(&gct);
+		let mut images = vec![];
+		for builder in self.imagebuilders.into_iter() {
+			images.push(builder.build());
 		}
 
-		self
-	}
-
-	fn write_images(&self, out: &mut OutVec) -> &Self {
-		//TODO: Deduplicate color table size code
-		let mcs = if let Some(gct) = &self.global_color_table {
-			((gct.len() as f32).log2().ceil() - 1f32) as u8
-		} else {
-			0
-		};
-
-		for ib in &self.imagebuilders {
-			let image = ib.write_to_vec(mcs);
-			out.push_slice(&image);
+		Gif {
+			header: self.version,
+			logical_screen_descriptor: lsd,
+			global_color_table: self.global_color_table,
+			images
 		}
-
-		self
-	}
-
-	fn write_trailer(&self, out: &mut OutVec) {
-		/*
-			"This block is a single-field block indicating the end of the GIF Data Stream. 
-			It contains the fixed value 0x3B."
-		*/
-		out.push_u8(0x3B);
-	}
-}
-
-#[cfg(test)]
-pub mod gifbuilder_test {
-	use super::*;
-
-	#[test]
-	pub fn writer_header() {
-		let mut out = OutVec::new();
-		GifBuilder::new(Version::Gif87a, 0, 0).write_header(&mut out);
-
-		assert_eq!(out.vec(), b"GIF87a");
-	}
-
-	#[test]
-	pub fn write_logical_screen_descriptor() {
-		let mut out = OutVec::new();
-		GifBuilder::new(Version::Gif87a, 4, 4).write_logical_screen_descriptor(&mut out);
-
-		assert_eq!(out.vec(), vec![0x04, 0x00, 0x04, 0x00, 0x00, 0x00, 0x00]);
-
-		let mut out = OutVec::new();
-		let gct = vec![
-			Color::new(0, 0, 0), Color::new(0, 0, 0), Color::new(0, 0, 0),
-			Color::new(0, 0, 0), Color::new(0, 0, 0)
-		];
-		GifBuilder::new(Version::Gif87a, 4, 4).global_color_table(gct).write_logical_screen_descriptor(&mut out);
-
-		assert_eq!(out.vec(), vec![0x04, 0x00, 0x04, 0x00, 0b1000_0010, 0x00, 0x00]);
-	}
-
-	#[test]
-	pub fn write_global_color_table() {
-		let mut out = OutVec::new();
-		let gct = vec![
-			Color::new(1, 2, 3), Color::new(253, 254, 255)
-		];
-		GifBuilder::new(Version::Gif87a, 4, 4).global_color_table(gct).write_global_color_table(&mut out);
-
-		assert_eq!(out.vec(), vec![1, 2, 3, 253, 254, 255]);
-	}
-
-	#[test]
-	fn write_images() {
-		let gct = vec![
-			Color::new(1, 2, 3), Color::new(253, 254, 255)
-		];
-		let colortable = vec![
-			Color::new(0, 0, 0), Color::new(128, 0, 255)
-		];
-		let indicies = vec![0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 0, 0];
-
-		let expected_out = vec![
-			0x2C, 0x00, 0x00, 0x00, 0x00, 0x04, 0x00, 0x04, 0x00, 0b1000_0000, // Image Descriptor 1
-			0, 0, 0, 128, 0, 255, // Color Table
-			0x02, 0x05, 0x84, 0x1D, 0x81, 0x7A, 0x50, 0x00, // Image Data 1
-			0x2C, 0x00, 0x00, 0x00, 0x00, 0x04, 0x00, 0x04, 0x00, 0b0000_0000, // Image Descriptor 2
-			0x02, 0x05, 0x84, 0x1D, 0x81, 0x7A, 0x50, 0x00 // Image Data 2
-		];
-
-		let mut out = OutVec::new();
-		GifBuilder::new(Version::Gif87a, 4, 4)
-			.global_color_table(gct)
-			.image(ImageBuilder::new(4, 4)
-				.color_table(colortable)
-				.indicies(indicies.clone())
-			).image(ImageBuilder::new(4, 4)
-				.indicies(indicies)
-			).write_images(&mut out);
-
-		assert_eq!(out.vec(), expected_out);
-	}
-
-	#[test]
-	fn write_to_vec() {
-		let gct = vec![
-			Color::new(1, 2, 3), Color::new(253, 254, 255)
-		];
-		let colortable = vec![
-			Color::new(0, 0, 0), Color::new(128, 0, 255)
-		];
-		let indicies = vec![0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 0, 0];
-
-		let expected_out = vec![
-			0x47, 0x49, 0x46, 0x38, 0x37, 0x61, // Version - GIF87a
-			0x04, 0x00, 0x04, 0x00, 0b1000_0000, 0x00, 0x00, // Logical Screen Descriptor
-			1, 2, 3, 253, 254, 255, // Global Color Table
-			0x2C, 0x00, 0x00, 0x00, 0x00, 0x04, 0x00, 0x04, 0x00, 0b1000_0000, // Image Descriptor 1
-			0, 0, 0, 128, 0, 255, // Color Table
-			0x02, 0x05, 0x84, 0x1D, 0x81, 0x7A, 0x50, 0x00, // Image Data 1
-			0x2C, 0x00, 0x00, 0x00, 0x00, 0x04, 0x00, 0x04, 0x00, 0b0000_0000, // Image Descriptor 2
-			0x02, 0x05, 0x84, 0x1D, 0x81, 0x7A, 0x50, 0x00, // Image Data 2
-			0x3B // Trailer
-		];
-
-		let mut out = OutVec::new();
-		let actual_out = GifBuilder::new(Version::Gif87a, 4, 4)
-			.global_color_table(gct)
-			.image(ImageBuilder::new(4, 4)
-				.color_table(colortable)
-				.indicies(indicies.clone())
-			).image(ImageBuilder::new(4, 4)
-				.indicies(indicies)
-			).write_to_vec();
-
-		assert_eq!(actual_out, expected_out);
 	}
 }
\ No newline at end of file
diff --git a/src/writer/imagebuilder.rs b/src/writer/imagebuilder.rs
index cd96908..0636bb3 100644
--- a/src/writer/imagebuilder.rs
+++ b/src/writer/imagebuilder.rs
@@ -1,13 +1,11 @@
-use crate::common::Color;
-use super::OutVec;
-use super::LZW;
+use crate::components::{ColorTable, Image, ImageDescriptor};
 
 pub struct ImageBuilder {
 	left_offset: u16,
 	top_offset: u16,
 	width: u16,
 	height: u16,
-	color_table: Option<Vec<Color>>,
+	color_table: Option<ColorTable>,
 	indicies: Vec<u8>
 }
 
@@ -39,13 +37,8 @@ impl ImageBuilder {
 		self
 	}
 
-	pub fn color_table(mut self, vec: Vec<Color>) -> Self {
-		if vec.len() == 0 || vec.len() > 256 {
-			//TODO: Throw error instead of panic
-			panic!("Color table has to be less than or 256 colors in size, and at least one");
-		}
-
-		self.color_table = Some(vec);
+	pub fn color_table(mut self, table: ColorTable) -> Self {
+		self.color_table = Some(table);
 
 		self
 	}
@@ -55,142 +48,24 @@ impl ImageBuilder {
 		self
 	}
 
-	//TODO: Make lzw_minimum_code_size optional. ONly needed with global color tables
-	pub fn write_to_vec(&self, lzw_minimum_code_size: u8) -> Vec<u8> {
-		let mut out = OutVec::new();
-
-		self.write_image_descriptor(&mut out)
-			.write_color_table(&mut out)
-			.write_image_data(&mut out, lzw_minimum_code_size);
-
-		out.vec()
-	}
-
-	fn write_image_descriptor(&self, out: &mut OutVec) -> &Self {
-		// Image seperator. At the start of every image descriptor
-		out.push_u8(0x2C)
-		.push_u16(self.left_offset)
-		.push_u16(self.top_offset)
-		.push_u16(self.width)
-		.push_u16(self.height);
-
-		// Taken from gifbuilder.rs
-		//TODO: deduplciate code
-		let mut packed: u8 = 0;
-		if let Some(ct) = &self.color_table {
-			packed |= 0b1000_0000; // Set the color table flag
-
-			let size = (ct.len() as f32).log2().ceil() - 1f32;
-			
-			packed |= size as u8;
+	pub fn build(self) -> Image {
+		let mut imgdesc = ImageDescriptor {
+			left: self.left_offset,
+			top: self.top_offset,
+			width: self.width,
+			height: self.height,
+			packed: 0 // Set later
+		};
+
+		if let Some(lct) = &self.color_table {
+			imgdesc.color_table_present(true);
+			imgdesc.color_table_size(lct.packed_len());
 		}
-		//TODO: Interlace and Sort flags in packed
-		out.push_u8(packed);
-
-		self
-	}
 
-	fn write_color_table(&self, out: &mut OutVec) -> &Self {
-		if let Some(ct) = &self.color_table {
-			out.push_colors(&ct);
+		Image {
+			image_descriptor: imgdesc,
+			local_color_table: self.color_table,
+			indicies: self.indicies
 		}
-
-		self
-	}
-
-	fn write_image_data(&self, out: &mut OutVec, minimum_code_size: u8) -> &Self {
-		let mut mcs = minimum_code_size;
-
-		//TODO: Deduplicate color table size code
-		if let Some(ct) = &self.color_table {
-			mcs = ((ct.len() as f32).log2().ceil() - 1f32) as u8;
-		}
-
-		if mcs < 2 {
-			// Must always be true: 2 <= mcs <= 8
-			mcs = 2;
-		}
-
-		// First write out the MCS
-		out.push_u8(mcs);
-
-		let compressed = LZW::encode(mcs, &self.indicies);
-		
-		for chunk in compressed.chunks(255) {
-			out.push_u8(chunk.len() as u8);
-			out.push_slice(chunk);
-		}
-		// Data block length 0 to indicate an end
-		out.push_u8(0x00);
-
-		self
 	}
 }
-
-#[cfg(test)]
-mod imagebuilder_test {
-	use super::*;
-
-	#[test]
-	fn write_to_vec() {
-		let colortable = vec![
-			Color::new(0, 0, 0),
-			Color::new(128, 0, 255)
-		];
-		let indicies = vec![0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 0, 0];
-
-		let expected_out = vec![
-			0x2C, 0x00, 0x00, 0x00, 0x00, 0x04, 0x00, 0x04, 0x00, 0b1000_0000, // Image Descriptor
-			0, 0, 0, 128, 0, 255, // Color Table
-			0x02, 0x05, 0x84, 0x1D, 0x81, 0x7A, 0x50, 0x00 // Image Data
-		];
-		let actual_out = ImageBuilder::new(4, 4)
-			.color_table(colortable)
-			.indicies(indicies)
-			.write_to_vec(0);
-
-		assert_eq!(actual_out, expected_out);
-	}
-
-	#[test]
-	fn write_image_descriptor() {
-		let mut out = OutVec::new();
-		ImageBuilder::new(16, 16).offsets(1, 6).write_image_descriptor(&mut out);
-
-		assert_eq!(out.vec(), vec![0x2C, 0x01, 0x00, 0x06, 0x00, 0x10, 0x00, 0x10, 0x00, 0x00]);
-
-		let mut out = OutVec::new();
-		ImageBuilder::new(16, 16)
-			.offsets(1, 6)
-			.color_table(vec![Color::new(0, 0, 0)])
-			.write_image_descriptor(&mut out);
-
-		assert_eq!(out.vec(), vec![0x2C, 0x01, 0x00, 0x06, 0x00, 0x10, 0x00, 0x10, 0x00, 0b1000_0000]);
-	}
-
-	#[test]
-	fn write_color_table() {
-		let mut out = OutVec::new();
-		ImageBuilder::new(16, 16)
-			.color_table(vec![Color::new(1, 2, 3), Color::new(253, 254, 255)])
-			.write_color_table(&mut out);
-
-		assert_eq!(out.vec(), vec![0x01, 0x02, 0x03, 0xFD, 0xFE, 0xFF]);
-	}
-
-	#[test]
-	fn write_image_data() {
-		#[test]
-		fn encode() {
-			let indicies = vec![0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 0, 0];
-			let output = vec![0x02, 0x05, 0x84, 0x1D, 0x81, 0x7A, 0x50, 0x00];
-
-			let mut out = OutVec::new();
-			ImageBuilder::new(16, 16)
-				.indicies(indicies)
-				.write_image_data(&mut out, 2);
-	
-			assert_eq!(out.vec(), output);
-		}
-	}
-}
\ No newline at end of file
diff --git a/src/writer/mod.rs b/src/writer/mod.rs
index 965dcfa..b801a3a 100644
--- a/src/writer/mod.rs
+++ b/src/writer/mod.rs
@@ -1,9 +1,5 @@
-mod outvec;
 mod gifbuilder;
-mod lzw;
 mod imagebuilder;
 
-use outvec::OutVec;
 pub use gifbuilder::GifBuilder;
-use lzw::LZW;
 pub use imagebuilder::ImageBuilder;
\ No newline at end of file
diff --git a/src/writer/outvec.rs b/src/writer/outvec.rs
deleted file mode 100644
index eb04934..0000000
--- a/src/writer/outvec.rs
+++ /dev/null
@@ -1,64 +0,0 @@
-use crate::common::Color;
-
-#[derive(Debug, PartialEq)]
-pub struct OutVec {
-	data: Vec<u8>
-}
-
-impl OutVec {
-	pub fn new() -> Self {
-		Self {
-			data: vec![]
-		}
-	}
-
-	pub fn push_u8(&mut self, n: u8) -> &mut Self {
-		self.data.push(n);
-		self
-	}
-
-	pub fn push_u16(&mut self, n: u16) -> &mut Self {
-		self.data.extend_from_slice(&n.to_le_bytes());
-		self
-	}
-
-	pub fn push_u32(&mut self, n: u32) -> &mut Self {
-		self.data.extend_from_slice(&n.to_le_bytes());
-		self
-	}
-
-	pub fn push_u64(&mut self, n: u64) -> &mut Self {
-		self.data.extend_from_slice(&n.to_le_bytes());
-		self
-	}
-
-	pub fn push_slice(&mut self, slice: &[u8]) -> &mut Self {
-		self.data.extend_from_slice(slice);
-		self
-	}
-
-	pub fn push_color(&mut self, color: &Color) -> &mut Self {
-		self.data.extend_from_slice(&[color.r, color.g, color.b]);
-		self
-	}
-
-	pub fn push_colors(&mut self, colors: &[Color]) -> &mut Self {
-		for color in colors {
-			self.push_color(color);
-		}
-		self
-	}
-
-	pub fn vec(self) -> Vec<u8> {
-		self.data
-	}
-}
-
-impl From<Vec<u8>> for OutVec {
-	fn from(v: Vec<u8>) -> Self {
-		let mut outvec = Self::new();
-		outvec.push_slice(&v);
-
-		outvec
-	}
-}
\ No newline at end of file