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use std::fmt;
#[derive(Debug, PartialEq, Clone, Copy)]
pub enum ColorType {
Grayscale,
RGB,
Indexed,
GrayscaleAlpha,
RGBA,
}
impl fmt::Display for ColorType {
#[inline]
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(
f,
"{}",
match *self {
ColorType::Grayscale => "Grayscale",
ColorType::RGB => "RGB",
ColorType::Indexed => "Indexed",
ColorType::GrayscaleAlpha => "Grayscale + Alpha",
ColorType::RGBA => "RGB + Alpha",
}
)
}
}
impl ColorType {
#[inline]
pub fn png_header_code(self) -> u8 {
match self {
ColorType::Grayscale => 0,
ColorType::RGB => 2,
ColorType::Indexed => 3,
ColorType::GrayscaleAlpha => 4,
ColorType::RGBA => 6,
}
}
#[inline]
pub fn channels_per_pixel(self) -> u8 {
match self {
ColorType::Grayscale | ColorType::Indexed => 1,
ColorType::GrayscaleAlpha => 2,
ColorType::RGB => 3,
ColorType::RGBA => 4,
}
}
}
#[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Clone, Copy)]
pub enum BitDepth {
One,
Two,
Four,
Eight,
Sixteen,
}
impl fmt::Display for BitDepth {
#[inline]
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(
f,
"{}",
match *self {
BitDepth::One => "1",
BitDepth::Two => "2",
BitDepth::Four => "4",
BitDepth::Eight => "8",
BitDepth::Sixteen => "16",
}
)
}
}
impl BitDepth {
#[inline]
pub fn as_u8(self) -> u8 {
match self {
BitDepth::One => 1,
BitDepth::Two => 2,
BitDepth::Four => 4,
BitDepth::Eight => 8,
BitDepth::Sixteen => 16,
}
}
#[inline]
pub fn from_u8(depth: u8) -> BitDepth {
match depth {
1 => BitDepth::One,
2 => BitDepth::Two,
4 => BitDepth::Four,
8 => BitDepth::Eight,
16 => BitDepth::Sixteen,
_ => panic!("Unsupported bit depth"),
}
}
}
#[derive(Debug, PartialEq, Clone, Copy, Eq, Hash)]
pub enum AlphaOptim {
NoOp,
Black,
White,
Up,
Right,
Down,
Left,
}
impl fmt::Display for AlphaOptim {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(
f,
"{}",
match *self {
AlphaOptim::NoOp => "_",
AlphaOptim::Black => "B",
AlphaOptim::White => "W",
AlphaOptim::Up => "U",
AlphaOptim::Right => "R",
AlphaOptim::Down => "D",
AlphaOptim::Left => "L",
}
)
}
}