13 files changed, 792 insertions, 0 deletions
diff --git a/dhwt-codec/.gitignore b/dhwt-codec/.gitignore
new file mode 100644
index 0000000..495c6ed
--- /dev/null
+++ b/dhwt-codec/.gitignore
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diff --git a/dhwt-codec/Cargo.lock b/dhwt-codec/Cargo.lock
new file mode 100644
index 0000000..715ba3e
--- /dev/null
+++ b/dhwt-codec/Cargo.lock
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diff --git a/dhwt-codec/Cargo.toml b/dhwt-codec/Cargo.toml
new file mode 100644
index 0000000..080fe20
--- /dev/null
+++ b/dhwt-codec/Cargo.toml
@@ -0,0 +1,9 @@
+[package]
+name = "dhwt-codec"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+bincode = "2.0.0-rc.2"
+clap = { version = "4.0.26", features = ["derive"] }
+rayon = "1.6.0"
diff --git a/dhwt-codec/run b/dhwt-codec/run
new file mode 100755
index 0000000..9f7013e
--- /dev/null
+++ b/dhwt-codec/run
@@ -0,0 +1,16 @@
+#!/bin/fish
+
+set f $argv[1]
+set x $argv[2]
+set y $argv[3]
+set z $argv[4]
+
+# cat /dev/urandom | cargo run --release --bin import -- -x $x -y $y -z $z a/inp
+ffmpeg -i $f -frames:v $z -filter_complex [0]scale={$x}x{$y},format=rgb24 -f rawvideo pipe:1 | cargo run --release --bin import -- -x $x -y $y -z $z a/inp
+
+time cargo run --release --bin encode -- -x $x -y $y -z $z a/inp a/enc
+time cargo run --release --bin decode -- -x $x -y $y -z $z a/enc a/out
+
+cargo run --release --bin export -- -x (math $x / 2) -y (math $y / 2) -z (math $z / 2) a/enc | ffmpeg -y -pixel_format rgb24 -f rawvideo -video_size (math $x / 2)x(math $y / 2) -i pipe:0 a/enc.webm
+cargo run --release --bin export -- -x $x -y $y -z $z a/out | ffmpeg -y -pixel_format rgb24 -f rawvideo -video_size {$x}x{$y} -i pipe:0 a/out.webm
+# cargo run --release --bin export -- -x $x -y $y -z $z a/raw_out | ffplay -pixel_format rgb24 -f rawvideo -video_size {$x}x{$y} pipe:0
diff --git a/dhwt-codec/src/bin/decode.rs b/dhwt-codec/src/bin/decode.rs
new file mode 100644
index 0000000..35881fc
--- /dev/null
+++ b/dhwt-codec/src/bin/decode.rs
@@ -0,0 +1,54 @@
+use clap::Parser;
+use dhwt_codec::{
+    io::{empty_videobuf, infile, outfile, read_videobuf_small, write_videobuf, VideoBuf},
+    transform, trim,
+    view::{BufferView, IndexMode},
+    CommonArgs,
+};
+use rayon::prelude::{IntoParallelIterator, ParallelIterator};
+
+fn main() {
+    let args = CommonArgs::parse();
+
+    let mut inf = infile(&args.infile);
+    let mut of = outfile(&args.outfile);
+
+    for c in 0..args.channels {
+        eprintln!("encoding channel #{c}");
+        let a = empty_videobuf(args.x, args.y, args.z);
+        let b = read_videobuf_small(&mut inf);
+
+        eprintln!("\tdecoding Z");
+        (0..args.x).into_par_iter().for_each(|x| {
+            for y in 0..args.y {
+                run_mode(make_mut(&b), make_mut(&a), IndexMode::XY(x, y), args.z)
+            }
+        });
+        eprintln!("\tdecoding Y");
+        (0..args.x).into_par_iter().for_each(|x| {
+            for z in 0..args.z {
+                run_mode(make_mut(&a), make_mut(&b), IndexMode::XZ(x, z), args.y)
+            }
+        });
+        eprintln!("\tdecoding X");
+        (0..args.y).into_par_iter().for_each(|y| {
+            for z in 0..args.z {
+                run_mode(make_mut(&b), make_mut(&a), IndexMode::YZ(y, z), args.x)
+            }
+        });
+        write_videobuf(&mut of, a);
+    }
+}
+
+fn run_mode(a: &mut VideoBuf, b: &mut VideoBuf, mode: IndexMode, size: usize) {
+    trim::untrim(size, &mut BufferView::new(b, mode));
+    transform::decode(
+        size,
+        &mut BufferView::new(a, mode),
+        &mut BufferView::new(b, mode),
+    );
+}
+
+fn make_mut<T>(r: &T) -> &mut T {
+    unsafe { &mut *((r as *const T) as *mut T) }
+}
diff --git a/dhwt-codec/src/bin/encode.rs b/dhwt-codec/src/bin/encode.rs
new file mode 100644
index 0000000..0e711b0
--- /dev/null
+++ b/dhwt-codec/src/bin/encode.rs
@@ -0,0 +1,54 @@
+use clap::Parser;
+use dhwt_codec::{
+    io::{empty_videobuf, infile, outfile, read_videobuf, write_videobuf_small, VideoBuf},
+    transform, trim,
+    view::{BufferView, IndexMode},
+    CommonArgs,
+};
+use rayon::prelude::{IntoParallelIterator, ParallelIterator};
+
+fn main() {
+    let args = CommonArgs::parse();
+
+    let mut inf = infile(&args.infile);
+    let mut of = outfile(&args.outfile);
+
+    for c in 0..args.channels {
+        eprintln!("encoding channel #{c}");
+        let o = empty_videobuf(args.x, args.y, args.z);
+        let i = read_videobuf(&mut inf);
+
+        eprintln!("\tencoding X");
+        (0..args.y).into_par_iter().for_each(|y| {
+            for z in 0..args.z {
+                run_mode(make_mut(&i), make_mut(&o), IndexMode::YZ(y, z), args.x)
+            }
+        });
+        eprintln!("\tencoding Y");
+        (0..args.x).into_par_iter().for_each(|x| {
+            for z in 0..args.z {
+                run_mode(make_mut(&o), make_mut(&i), IndexMode::XZ(x, z), args.y)
+            }
+        });
+        eprintln!("\tencoding Z");
+        (0..args.x).into_par_iter().for_each(|x| {
+            for y in 0..args.y {
+                run_mode(make_mut(&i), make_mut(&o), IndexMode::XY(x, y), args.z)
+            }
+        });
+        write_videobuf_small(&mut of, o);
+    }
+}
+
+fn run_mode(a: &mut VideoBuf, b: &mut VideoBuf, mode: IndexMode, size: usize) {
+    transform::encode(
+        size,
+        &mut BufferView::new(a, mode),
+        &mut BufferView::new(b, mode),
+    );
+    trim::trim(size, &mut BufferView::new(b, mode));
+}
+
+fn make_mut<T>(r: &T) -> &mut T {
+    unsafe { &mut *((r as *const T) as *mut T) }
+}
diff --git a/dhwt-codec/src/bin/export.rs b/dhwt-codec/src/bin/export.rs
new file mode 100644
index 0000000..73f3067
--- /dev/null
+++ b/dhwt-codec/src/bin/export.rs
@@ -0,0 +1,42 @@
+use clap::Parser;
+use dhwt_codec::io::{infile, read_videobuf};
+use std::io::{stdout, BufWriter, Write};
+
+#[derive(Parser)]
+#[clap(about)]
+struct ExportArgs {
+    #[arg(short)]
+    x: usize,
+    #[arg(short)]
+    y: usize,
+    #[arg(short)]
+    z: usize,
+
+    #[arg(short, long, default_value = "3")]
+    channels: usize,
+
+    infile: String,
+}
+
+fn main() {
+    let args = ExportArgs::parse();
+
+    let mut i = infile(&args.infile);
+    let mut writer = BufWriter::new(stdout());
+
+    let mut channels = vec![];
+    for _ in 0..args.channels {
+        channels.push(read_videobuf(&mut i))
+    }
+
+    for z in 0..args.z {
+        for y in 0..args.y {
+            for x in 0..args.x {
+                for c in 0..args.channels {
+                    writer.write_all(&[channels[c][x][y][z] as u8]).unwrap();
+                }
+            }
+        }
+    }
+    writer.flush().unwrap();
+}
diff --git a/dhwt-codec/src/bin/import.rs b/dhwt-codec/src/bin/import.rs
new file mode 100644
index 0000000..cd2a35e
--- /dev/null
+++ b/dhwt-codec/src/bin/import.rs
@@ -0,0 +1,51 @@
+use clap::Parser;
+use dhwt_codec::io::{outfile, write_videobuf, Value};
+use std::io::{stdin, Read};
+
+#[derive(Parser)]
+#[clap(about)]
+struct ImportArgs {
+    #[arg(short)]
+    x: usize,
+    #[arg(short)]
+    y: usize,
+    #[arg(short)]
+    z: usize,
+
+    #[arg(short, long, default_value = "3")]
+    channels: usize,
+
+    outfile: String,
+}
+
+fn main() {
+    let args = ImportArgs::parse();
+
+    let mut rawbuf = (0..(args.x * args.y * args.z * args.channels))
+        .map(|_| 0u8)
+        .collect::<Vec<_>>();
+    stdin().read_exact(&mut rawbuf).unwrap();
+
+    let mut o = outfile(&args.outfile);
+
+    for c in 0..args.channels {
+        let mut cols = vec![];
+        for x in 0..args.x {
+            let mut col = vec![];
+            for y in 0..args.y {
+                let mut span = vec![];
+                for z in 0..args.z {
+                    span.push(
+                        rawbuf[c
+                            + (x * args.channels)
+                            + (y * args.channels * args.x)
+                            + (z * args.channels * args.x * args.y)] as Value,
+                    );
+                }
+                col.push(span);
+            }
+            cols.push(col)
+        }
+        write_videobuf(&mut o, cols)
+    }
+}
diff --git a/dhwt-codec/src/io.rs b/dhwt-codec/src/io.rs
new file mode 100644
index 0000000..c60bc79
--- /dev/null
+++ b/dhwt-codec/src/io.rs
@@ -0,0 +1,71 @@
+use bincode::config;
+use std::{
+    fs::File,
+    io::{BufReader, BufWriter, Read, Write},
+};
+
+pub type Value = f32;
+pub type VideoBuf = Vec<Vec<Vec<Value>>>;
+pub const ZERO: Value = 0 as Value;
+pub const TWO: Value = 2 as Value;
+
+pub fn empty_videobuf(x: usize, y: usize, z: usize) -> VideoBuf {
+    (0..x)
+        .map(|_| (0..y).map(|_| (0..z).map(|_| ZERO).collect()).collect())
+        .collect()
+}
+
+pub fn outfile(p: &str) -> impl Write {
+    BufWriter::new(File::create(p).unwrap())
+}
+pub fn infile(p: &str) -> impl Read {
+    BufReader::new(File::open(p).unwrap())
+}
+
+pub fn read_videobuf(f: &mut impl Read) -> VideoBuf {
+    bincode::decode_from_std_read(f, config::standard()).unwrap()
+}
+pub fn write_videobuf(f: &mut impl Write, i: VideoBuf) {
+    bincode::encode_into_std_write(i, f, config::standard()).unwrap();
+}
+
+pub fn write_videobuf_small(f: &mut impl Write, mut i: VideoBuf) {
+    for _ in 0..(i.len() / 2) {
+        i.pop();
+    }
+    for i in &mut i {
+        for _ in 0..(i.len() / 2) {
+            i.pop();
+        }
+        for i in i {
+            for _ in 0..(i.len() / 2) {
+                i.pop();
+            }
+        }
+    }
+    write_videobuf(f, i);
+}
+pub fn read_videobuf_small(f: &mut impl Read) -> VideoBuf {
+    let mut i = read_videobuf(f);
+
+    for i in &mut i {
+        for i in i {
+            for _ in 0..i.len() {
+                i.push(ZERO);
+            }
+        }
+    }
+    for i in &mut i {
+        for _ in 0..i.len() {
+            i.push((0..i[0].len()).map(|_| ZERO).collect());
+        }
+    }
+    for _ in 0..i.len() {
+        i.push(
+            (0..i[0].len())
+                .map(|_| ((0..i[0][0].len()).map(|_| ZERO)).collect())
+                .collect(),
+        );
+    }
+    i
+}
diff --git a/dhwt-codec/src/lib.rs b/dhwt-codec/src/lib.rs
new file mode 100644
index 0000000..69d6b4c
--- /dev/null
+++ b/dhwt-codec/src/lib.rs
@@ -0,0 +1,23 @@
+use clap::Parser;
+
+pub mod io;
+pub mod transform;
+pub mod trim;
+pub mod view;
+
+#[derive(Parser)]
+#[clap(about)]
+pub struct CommonArgs {
+    #[arg(short)]
+    pub x: usize,
+    #[arg(short)]
+    pub y: usize,
+    #[arg(short)]
+    pub z: usize,
+
+    #[arg(short, long, default_value = "3")]
+    pub channels: usize,
+
+    pub infile: String,
+    pub outfile: String,
+}
diff --git a/dhwt-codec/src/transform.rs b/dhwt-codec/src/transform.rs
new file mode 100644
index 0000000..82bccd1
--- /dev/null
+++ b/dhwt-codec/src/transform.rs
@@ -0,0 +1,42 @@
+use crate::io::{Value, TWO};
+use std::ops::{Index, IndexMut};
+
+pub fn encode<X: Index<usize, Output = Value> + IndexMut<usize, Output = Value>>(
+    size: usize,
+    a: &mut X,
+    b: &mut X,
+) {
+    let mut k = size;
+    while k != 1 {
+        k /= 2;
+        for i in 0..k {
+            let x = a[i * 2];
+            let y = a[i * 2 + 1];
+            b[i] = x + y;
+            b[k + i] = x - y;
+        }
+        for i in 0..k {
+            a[i] = b[i]
+        }
+    }
+}
+
+pub fn decode<X: Index<usize, Output = Value> + IndexMut<usize, Output = Value>>(
+    size: usize,
+    a: &mut X,
+    b: &mut X,
+) {
+    let mut k = 1;
+    while k != size {
+        for i in 0..k {
+            let avr = a[i] / TWO;
+            let spread = a[i + k] / TWO;
+            b[i * 2] = avr + spread;
+            b[i * 2 + 1] = avr - spread;
+        }
+        k *= 2;
+        for i in 0..k {
+            a[i] = b[i]
+        }
+    }
+}
diff --git a/dhwt-codec/src/trim.rs b/dhwt-codec/src/trim.rs
new file mode 100644
index 0000000..85a920a
--- /dev/null
+++ b/dhwt-codec/src/trim.rs
@@ -0,0 +1,36 @@
+use crate::io::{Value, TWO, ZERO};
+use std::ops::{Index, IndexMut};
+
+pub fn trim<X: Index<usize, Output = Value> + IndexMut<usize, Output = Value>>(
+    size: usize,
+    a: &mut X,
+) {
+    let half = size / 2;
+    let quarter = size / 4;
+    for i in 0..(size / 2 / 4) {
+        let hi = half + i * 4;
+        let qi = quarter + i * 2;
+        a[qi] = (a[qi + 0] + a[qi + 1]) / TWO;
+        a[qi + 1] = (a[hi + 0] + a[hi + 1] + a[hi + 2] + a[hi + 3]) / (TWO * TWO);
+    }
+    for i in half..size {
+        a[i] = ZERO;
+    }
+}
+
+pub fn untrim<X: Index<usize, Output = Value> + IndexMut<usize, Output = Value>>(
+    size: usize,
+    a: &mut X,
+) {
+    let half = size / 2;
+    let quarter = size / 4;
+    for i in 0..(size / 2 / 4) {
+        let hi = half + i * 4;
+        let qi = quarter + i * 2;
+        a[hi + 0] = a[qi + 1];
+        a[hi + 1] = a[qi + 1];
+        a[hi + 2] = a[qi + 1];
+        a[hi + 3] = a[qi + 1];
+        a[qi + 1] = a[qi];
+    }
+}
diff --git a/dhwt-codec/src/view.rs b/dhwt-codec/src/view.rs
new file mode 100644
index 0000000..0f2ecf7
--- /dev/null
+++ b/dhwt-codec/src/view.rs
@@ -0,0 +1,42 @@
+use std::ops::{Index, IndexMut};
+
+use crate::io::{VideoBuf, Value};
+
+#[derive(Copy, Clone, Debug)]
+pub enum IndexMode {
+    XY(usize, usize),
+    XZ(usize, usize),
+    YZ(usize, usize),
+}
+
+pub struct BufferView<'a> {
+    mode: IndexMode,
+    buf: &'a mut VideoBuf,
+}
+
+impl<'a> BufferView<'a> {
+    pub fn new(buf: &'a mut VideoBuf, mode: IndexMode) -> Self {
+        BufferView { mode, buf }
+    }
+}
+
+impl Index<usize> for BufferView<'_> {
+    type Output = Value;
+
+    fn index(&self, a: usize) -> &Self::Output {
+        match self.mode {
+            IndexMode::XY(x, y) => &self.buf[x][y][a],
+            IndexMode::XZ(x, z) => &self.buf[x][a][z],
+            IndexMode::YZ(y, z) => &self.buf[a][y][z],
+        }
+    }
+}
+impl IndexMut<usize> for BufferView<'_> {
+    fn index_mut(&mut self, a: usize) -> &mut Self::Output {
+        match self.mode {
+            IndexMode::XY(x, y) => &mut self.buf[x][y][a],
+            IndexMode::XZ(x, z) => &mut self.buf[x][a][z],
+            IndexMode::YZ(y, z) => &mut self.buf[a][y][z],
+        }
+    }
+}