bendns' repos / fimg
fast image operations
Diffstat (limited to 'src/term/sixel.rs')
-rw-r--r--src/term/sixel.rs128
1 files changed, 128 insertions, 0 deletions
diff --git a/src/term/sixel.rs b/src/term/sixel.rs
new file mode 100644
index 0000000..46f2b55
--- /dev/null
+++ b/src/term/sixel.rs
@@ -0,0 +1,128 @@
+use std::fmt::{Debug, Display, Formatter, Result, Write};
+
+use crate::{pixels::convert::PFrom, Image};
+
+/// Outputs [sixel](https://en.wikipedia.org/wiki/Sixel) encoded data in its [`Display`] and [`Debug`] implementations, for easy visual debugging.
+pub struct Sixel<T: AsRef<[u8]>, const N: usize>(pub Image<T, N>);
+
+impl<T: AsRef<[u8]>, const N: usize> std::ops::Deref for Sixel<T, N> {
+ type Target = Image<T, N>;
+
+ fn deref(&self) -> &Self::Target {
+ &self.0
+ }
+}
+
+impl<T: AsRef<[u8]>, const N: usize> Display for Sixel<T, N>
+where
+ [u8; 4]: PFrom<N>,
+{
+ fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+ self.write(f)
+ }
+}
+
+impl<T: AsRef<[u8]>, const N: usize> Debug for Sixel<T, N>
+where
+ [u8; 4]: PFrom<N>,
+{
+ fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+ self.write(f)
+ }
+}
+
+impl<T: AsRef<[u8]>, const N: usize> Sixel<T, N> {
+ /// Write out sixel data.
+ pub fn write(&self, to: &mut impl Write) -> Result
+ where
+ [u8; 4]: PFrom<N>,
+ {
+ to.write_str("Pq")?;
+ write!(to, r#""1;1;{};{}"#, self.width(), self.height())?;
+ let buf;
+ let rgba = if N == 4 {
+ // SAFETY: buffer cannot have half pixels (cant use flatten bcoz N)
+ unsafe { self.buffer().as_ref().as_chunks_unchecked() }
+ } else {
+ buf = self
+ .chunked()
+ .copied()
+ .map(<[u8; 4] as PFrom<N>>::pfrom)
+ .collect::<Vec<_>>();
+ &*buf
+ };
+
+ let q = qwant::NeuQuant::new(15, 255, rgba);
+ // TODO: don't colllect
+ let pixels: Vec<u8> = rgba.iter().map(|&pix| q.index_of(pix) as u8).collect();
+
+ for ([r, g, b], i) in q
+ .color_map_rgb()
+ .map(|x| x.map(|x| (x as f32 * (100. / 255.)) as u32))
+ .zip(0u8..)
+ {
+ write!(to, "#{i};2;{r};{g};{b}")?;
+ }
+ for sixel_row in pixels.chunks_exact(self.width() as usize * 6).map(|x| {
+ let mut x = x
+ .iter()
+ .zip(0u32..)
+ .map(|(&p, j)| (p, (j % self.width(), j / self.width())))
+ .collect::<Vec<_>>();
+ x.sort_unstable();
+ x
+ }) {
+ // extracted
+ for samples in Grouped(&sixel_row, |r| r.0) {
+ write!(to, "#{}", samples[0].0)?;
+ let mut last = -1;
+ for (x, byte) in Grouped(samples, |(_, (x, _))| x).map(|v| {
+ (
+ v[0].1 .0 as i32,
+ v.iter()
+ .map(|&(_, (_, y))| (1 << y))
+ .fold(0, |acc, x| acc | x),
+ )
+ }) {
+ if last + 1 != x {
+ write!(to, "!{}?", x - last - 1)?;
+ }
+ to.write_char((byte + b'?') as char)?;
+ last = x;
+ }
+
+ write!(to, "$")?;
+ }
+ write!(to, "-")?;
+ }
+ write!(to, r"\")?;
+
+ Ok(())
+ }
+}
+
+struct Grouped<'a, K: Eq, T, F: Fn(T) -> K>(&'a [T], F);
+impl<'a, K: Eq, T: Copy, F: Fn(T) -> K> Iterator for Grouped<'a, K, T, F> {
+ type Item = &'a [T];
+ fn next(&mut self) -> Option<Self::Item> {
+ self.0.first()?;
+ self.0
+ .split_at_checked(
+ self.0
+ .array_windows::<2>()
+ .take_while(|&&[a, b]| (self.1)(a) == (self.1)(b))
+ .count()
+ + 1,
+ )
+ .inspect(|(_, t)| self.0 = t)
+ .map(|(h, _)| h)
+ }
+}
+
+#[test]
+fn test() {
+ assert_eq!(
+ Sixel(Image::<Vec<u8>, 3>::open("tdata/small_cat.png")).to_string(),
+ include_str!("../../tdata/small_cat.six")
+ );
+}