working

Cargo.toml

@@ -3,16 +3,12 @@ name = "pi-frame-server"
 version = "0.1.0"
 edition = "2021"
 
-[features]
-gui = []
-spi = ["dep:epd-waveshare", "dep:linux-embedded-hal"]
-
 [dependencies]
 anyhow = "1.0.86"
 clap = { version = "4.5.7", features = ["derive"] }
-epd-waveshare = { git = "https://github.com/caemor/epd-waveshare.git", optional = true }
+epd-waveshare = { git = "https://github.com/caemor/epd-waveshare.git" }
 image = "0.25.1"
-linux-embedded-hal = { version = "0.4.0", optional = true }
+linux-embedded-hal = { version = "0.4.0" }
 num-traits = "0.2.19"
 palette = "0.7.6"
 rayon = "1.10.0"

build.sh

@@ -0,0 +1,6 @@
+#!/bin/bash
+set +x
+cross build --target aarch64-unknown-linux-gnu
+rsync -aczP target/aarch64-unknown-linux-gnu/debug/pi-frame-server 192.168.0.186:
+# scp target/aarch64-unknown-linux-gnu/debug/pi-frame-server 192.168.0.186:
+ssh 192.168.0.186 ./pi-frame-server load

src/display.rs

@@ -0,0 +1,88 @@
+use epd_waveshare::{epd7in3f::Epd7in3f, prelude::WaveshareDisplay};
+use linux_embedded_hal::spidev::SpiModeFlags;
+use linux_embedded_hal::spidev::SpidevOptions;
+use linux_embedded_hal::{CdevPin, Delay, SpidevBus, SpidevDevice};
+
+use linux_embedded_hal::gpio_cdev::{Chip, LineRequestFlags};
+use anyhow::Result;
+
+pub fn demo() -> Result<()> {
+    let mut spi = SpidevDevice::open("/dev/spidev0.0")?;
+    let spi_options = SpidevOptions::new()
+        .bits_per_word(8)
+        .max_speed_hz(10_000_000)
+        .mode(SpiModeFlags::SPI_MODE_0)
+        .build();
+    spi.configure(&spi_options)?;
+    let mut gpiochip = Chip::new("/dev/gpiochip0")?;
+    let busy_pin = CdevPin::new(gpiochip.get_line(24)?.request(
+        LineRequestFlags::INPUT,
+        0,
+        "frametool",
+    )?)?;
+    let dc_pin = CdevPin::new(gpiochip.get_line(25)?.request(
+        LineRequestFlags::OUTPUT,
+        0,
+        "frametool",
+    )?)?;
+    let rst_pin = CdevPin::new(gpiochip.get_line(17)?.request(
+        LineRequestFlags::OUTPUT,
+        0,
+        "frametool",
+    )?)?;
+    let mut delay = Delay {};
+
+    let mut panel = Epd7in3f::new(&mut spi, busy_pin, dc_pin, rst_pin, &mut delay, None)?;
+    panel.show_7block(&mut spi, &mut delay)?;
+    Ok(())
+}
+
+
+pub struct DisplayWrapper {
+    spi: SpidevDevice,
+    gpiochip: Chip,
+    delay: Delay,
+    panel: Epd7in3f<SpidevDevice, CdevPin, CdevPin, CdevPin, Delay>
+}
+
+impl DisplayWrapper {
+    pub fn new() -> Result<DisplayWrapper> {
+        let mut spi = SpidevDevice::open("/dev/spidev0.0")?;
+        let spi_options = SpidevOptions::new()
+            .bits_per_word(8)
+            .max_speed_hz(10_000_000)
+            .mode(SpiModeFlags::SPI_MODE_0)
+            .build();
+        spi.configure(&spi_options)?;
+
+        let mut gpiochip = Chip::new("/dev/gpiochip0")?;
+        let busy_pin = CdevPin::new(gpiochip.get_line(24)?.request(
+            LineRequestFlags::INPUT,
+            0,
+            "frametool",
+        )?)?;
+        let dc_pin = CdevPin::new(gpiochip.get_line(25)?.request(
+            LineRequestFlags::OUTPUT,
+            0,
+            "frametool",
+        )?)?;
+        let rst_pin = CdevPin::new(gpiochip.get_line(17)?.request(
+            LineRequestFlags::OUTPUT,
+            0,
+            "frametool",
+        )?)?;
+        let mut delay = Delay {};
+        let panel = Epd7in3f::new(&mut spi, busy_pin, dc_pin, rst_pin, &mut delay, None)?;
+
+        Ok(DisplayWrapper {
+            spi,
+            gpiochip,
+            delay,
+            panel
+        })
+    }
+    pub fn display(&mut self, buf: &[u8]) -> Result<()>{
+        self.panel.update_and_display_frame(&mut self.spi, buf, &mut self.delay)?;
+        Ok(())
+    }
+}

src/imageproc.rs

@@ -1,8 +1,7 @@
-use image::ColorType::Rgb8;
 
 use image::RgbImage;
 
-use palette::{cast::FromComponents, color_difference::EuclideanDistance, FromColor, IntoColor, Oklab, Srgb};
+use palette::{cast::FromComponents, color_difference::Ciede2000, IntoColor, Lab, Srgb};
 
 /// Palette used on the display; pixels can be one of these colors.
 ///
@@ -41,9 +40,9 @@ pub enum DisplayColor {
     Orange,
 }
 
-impl Into<Srgb> for DisplayColor {
-    fn into(self) -> Srgb {
-        DISPLAY_PALETTE[self as usize]
+impl From<DisplayColor> for Srgb {
+    fn from(value: DisplayColor) -> Self {
+        DISPLAY_PALETTE[value as usize]
     }
 }
 
@@ -60,34 +59,62 @@ impl DisplayColor {
             _ => panic!("unexpected DisplayColor {}", value),
         }
     }
-}
 
+    fn into_byte(color1: Self, color2: Self) -> u8 {
+        let upper: u8 = color1.into();
+        let lower: u8 = color2.into();
+        upper << 4 | lower
+    }
+}
+impl From<DisplayColor> for u8 {
+    fn from(value: DisplayColor) -> Self {
+        value as u8
+    }
+}
 /// Buffer to be sent to the EInk display.
 #[derive(Debug)]
-pub struct EInkBuffer {
-    data: Vec<DisplayColor>,
-    width: usize,
-    height: usize,
-}
+pub struct EInkBuffer(Vec<DisplayColor>);
 
 impl EInkBuffer {
-    /// Converts the EInkBuffer into data that can be sent over the SPI API
-    /// Bin-packs the two 4-bit colors into bytes.
-    pub fn into_buffer(&self) -> Vec<u8> {
-        vec![]
+    pub fn into_display_buffer(&self) -> Vec<u8> {
+        let mut buf = Vec::with_capacity(self.0.len()/2);
+
+        for colors in self.0.chunks_exact(2) {
+            buf.push(DisplayColor::into_byte(colors[0], colors[1]));
         }
 
-    pub fn new(width: usize, height: usize) -> EInkBuffer {
-        EInkBuffer {
-            data: vec![DisplayColor::Black; width * height],
-            width,
-            height,
+        buf
     }
+    pub fn new(width: usize, height: usize) -> Self {
+        let v = vec![DisplayColor::Black; width * height];
+        EInkBuffer(v)
     }
 }
 
+// impl EInkBuffer {
+//     /// Converts the EInkBuffer into data that can be sent over the SPI API
+//     /// Bin-packs the two 4-bit colors into bytes.
+//     pub fn into_buffer(&self) -> Vec<u8> {
+//         vec![]
+//     }
+//
+//     pub fn new(width: usize, height: usize) -> EInkBuffer {
+//         EInkBuffer {
+//             data: vec![DisplayColor::Black; width * height],
+//             width,
+//             height,
+//         }
+//     }
+//     pub fn set(&mut self, x: usize, y: usize, value: DisplayColor) {
+//         self.data[x + y * self.width] = value;
+//     }
+//     pub fn get(&self, x:usize, y:usize) -> DisplayColor {
+//         self.data[x 
+//     }
+// }
+
 pub trait Ditherer {
-    fn dither(&self, img: &RgbImage) -> EInkBuffer;
+    fn dither(&self, img: &RgbImage, output: &mut EInkBuffer);
 }
 
 // fn color_distance(c1: LinSrgb, c2: LinSrgb) -> f32 {
@@ -101,13 +128,14 @@ pub trait Ditherer {
 /// Find the closest approximate palette color to the given sRGB value.
 /// This uses euclidian distance in linear space.
 pub fn nearest_neighbor(color: Srgb) -> (DisplayColor, f32) {
+    let input: Lab = color.into_color();
 
     let (nearest, dist) = DISPLAY_PALETTE
         .iter()
         .enumerate()
         .map(|(idx, p_color)| {
-            let lab: Oklab = p_color.clone().into_color();
-            (idx, color.distance(p_color.into_format()))
+            let c: Lab = (*p_color).into_color();
+            (idx, input.difference(c))
         })
         .min_by(|(_, a), (_, b)| a.total_cmp(b))
         .unwrap();
@@ -117,14 +145,18 @@ pub fn nearest_neighbor(color: Srgb) -> (DisplayColor, f32) {
 pub struct NNDither();
 
 impl Ditherer for NNDither {
-    fn dither(&self, img: &RgbImage) -> EInkBuffer {
+    fn dither(&self, img: &RgbImage, output: &mut EInkBuffer) {
         assert!(img.width() == 800);
         assert!(img.height() == 480);
-        let mut buf = EInkBuffer::new(800, 480);
-        // img.enumerate_pixels().for_each(|(x, y, pix)| {
-        //     buf[x + y * 800] = nearest_neighbor(Srgb::from_components());
-        // });
+        
+        // sRGB view into the given image. zero copy!
         let srgb = <&[Srgb<u8>]>::from_components(&**img);
-        buf
+
+        for (idx, pixel) in srgb.iter().enumerate() {
+            let (n, _) = nearest_neighbor(pixel.into_format());
+            output.0[idx] = n;
+        }
+
     }
 }
+

src/main.rs

@@ -1,9 +1,12 @@
-use clap::{Args, Parser, Subcommand};
-use epd_waveshare::{epd7in3f::Epd7in3f, prelude::WaveshareDisplay};
-
+pub mod display;
 pub mod imageproc;
 
-/// The main
+use crate::display::DisplayWrapper;
+use crate::imageproc::{Ditherer, EInkBuffer, NNDither};
+use clap::{Parser, Subcommand};
+use image::RgbImage;
+
+/// Display images over
 #[derive(Debug, Parser)]
 #[command(version, about)]
 struct Cli {
@@ -14,47 +17,25 @@ struct Cli {
 #[derive(Debug, Subcommand)]
 enum Command {
     /// Load a single image
-    Load,
+    Show,
     /// Start the HTTP sever
     Serve,
 }
 
-use linux_embedded_hal::spidev::SpidevOptions;
-use linux_embedded_hal::spidev::SpiModeFlags;
-use linux_embedded_hal::{CdevPin, Delay, SpidevBus, SpidevDevice};
-
-use linux_embedded_hal::gpio_cdev::{Chip, LineRequestFlags};
-
 fn main() -> anyhow::Result<()> {
     let cli = Cli::parse();
     println!("CLI {cli:?}");
-    if let Command::Load = cli.command {
-        println!("loading");
 
-        let mut spi = SpidevDevice::open("/dev/spidev0.0")?;
-        let spi_options = SpidevOptions::new().bits_per_word(8).max_speed_hz(10_000_000).mode(SpiModeFlags::SPI_MODE_0).build();
-        spi.configure(&spi_options)?;
-        let mut gpiochip = Chip::new("/dev/gpiochip0")?;
-        let busy_pin = CdevPin::new(gpiochip.get_line(24)?.request(
-            LineRequestFlags::INPUT,
-            0,
-            "frametool",
-        )?)?;
-        let dc_pin = CdevPin::new(gpiochip.get_line(25)?.request(
-            LineRequestFlags::OUTPUT,
-            0,
-            "frametool",
-        )?)?;
-        let rst_pin = CdevPin::new(gpiochip.get_line(17)?.request(
-            LineRequestFlags::OUTPUT,
-            0,
-            "frametool",
-        )?)?;
-        let mut delay = Delay { };
+    if let Command::Show = cli.command {
+        let img: RgbImage = image::io::Reader::open("myimage.png")?.decode()?.into();
+        let mut display = DisplayWrapper::new()?;
 
-        let mut panel = Epd7in3f::new(&mut spi, busy_pin, dc_pin, rst_pin, &mut delay, None)?;
-        panel.show_7block(&mut spi, &mut delay)?;
+        let mut eink_buf = EInkBuffer::new(800, 480);
+        let dither = NNDither {};
 
+        dither.dither(&img, &mut eink_buf);
+        let raw_buf = eink_buf.into_display_buffer();
+        display.display(&raw_buf)?;
     }
 
     Ok(())