diff --git a/src/cli.rs b/src/cli.rs
index 12a478e..1ee5783 100644
--- a/src/cli.rs
+++ b/src/cli.rs
@@ -114,14 +114,6 @@ pub enum StreamCommand {
#[derive(clap::Parser, std::fmt::Debug, Clone)]
pub struct StreamScreenOptions {
- #[arg(
- long,
- short,
- default_value_t = false,
- help = "Disable dithering - improves performance"
- )]
- pub no_dither: bool,
-
#[arg(
long,
short,
diff --git a/src/ledwand_dither.rs b/src/ledwand_dither.rs
index 135515c..be1091e 100644
--- a/src/ledwand_dither.rs
+++ b/src/ledwand_dither.rs
@@ -1,17 +1,7 @@
//! Based on https://github.com/WarkerAnhaltRanger/CCCB_Ledwand
-use image::{GenericImage, GrayImage};
-use servicepoint::{PIXEL_HEIGHT, PIXEL_WIDTH};
-
-pub struct LedwandDither {
- options: LedwandDitherOptions,
- tmpbuf: GrayImage,
-}
-
-#[derive(Debug, Default)]
-pub struct LedwandDitherOptions {
- pub size: Option<(u32, u32)>,
-}
+use image::GrayImage;
+use servicepoint::{BitVec, Bitmap, PIXEL_HEIGHT};
type GrayHistogram = [usize; 256];
@@ -21,164 +11,495 @@ struct HistogramCorrection {
factor: f32,
}
-impl LedwandDither {
- pub fn new(options: LedwandDitherOptions) -> Self {
- let (width, height) = options
- .size
- .unwrap_or((PIXEL_WIDTH as u32, PIXEL_HEIGHT as u32));
- Self {
- tmpbuf: GrayImage::new(width, height),
- options,
+pub fn histogram_correction(image: &mut GrayImage) {
+ let histogram = make_histogram(image);
+ let correction = determine_histogram_correction(image, histogram);
+ apply_histogram_correction(image, correction)
+}
+
+fn make_histogram(image: &GrayImage) -> GrayHistogram {
+ let mut histogram = [0; 256];
+ for pixel in image.pixels() {
+ histogram[pixel.0[0] as usize] += 1;
+ }
+ histogram
+}
+
+fn determine_histogram_correction(
+ image: &GrayImage,
+ histogram: GrayHistogram,
+) -> HistogramCorrection {
+ let adjustment_pixels = image.len() / PIXEL_HEIGHT;
+
+ let mut num_pixels = 0;
+ let mut brightness = 0;
+
+ let mincut = loop {
+ num_pixels += histogram[brightness as usize];
+ brightness += 1;
+ if num_pixels >= adjustment_pixels {
+ break u8::min(brightness, 20);
+ }
+ };
+
+ let minshift = loop {
+ num_pixels += histogram[brightness as usize];
+ brightness += 1;
+ if num_pixels >= 2 * adjustment_pixels {
+ break u8::min(brightness, 64);
+ }
+ };
+
+ brightness = u8::MAX;
+ num_pixels = 0;
+ let maxshift = loop {
+ num_pixels += histogram[brightness as usize];
+ brightness -= 1;
+ if num_pixels >= 2 * adjustment_pixels {
+ break u8::max(brightness, 192);
+ }
+ };
+
+ let pre_offset = -(mincut as f32 / 2.);
+ let post_offset = -(minshift as f32);
+ let factor = (255.0 - post_offset) / maxshift as f32;
+ HistogramCorrection {
+ pre_offset,
+ post_offset,
+ factor,
+ }
+}
+
+fn apply_histogram_correction(image: &mut GrayImage, correction: HistogramCorrection) {
+ for pixel in image.pixels_mut() {
+ let pixel = &mut pixel.0[0];
+ let value =
+ (*pixel as f32 + correction.pre_offset) * correction.factor + correction.post_offset;
+ *pixel = value.clamp(0f32, u8::MAX as f32) as u8;
+ }
+}
+
+pub fn median_brightness(image: &GrayImage) -> u8 {
+ let histogram = make_histogram(image);
+ let midpoint = image.len() / 2;
+
+ debug_assert_eq!(
+ image.len(),
+ histogram.iter().copied().map(usize::from).sum()
+ );
+
+ let mut num_pixels = 0;
+ for brightness in u8::MIN..=u8::MAX {
+ num_pixels += histogram[brightness as usize];
+ if num_pixels >= midpoint {
+ return brightness;
}
}
- pub fn histogram_correction(image: &mut GrayImage) {
- let histogram = Self::make_histogram(image);
- let correction = Self::determine_histogram_correction(image, histogram);
- Self::apply_histogram_correction(image, correction)
+ unreachable!("Somehow less pixels where counted in the histogram than exist in the image")
+}
+
+pub fn blur(source: &GrayImage, destination: &mut GrayImage) {
+ assert_eq!(source.len(), destination.len());
+
+ copy_border(source, destination);
+ blur_inner_pixels(source, destination);
+}
+
+pub fn sharpen(source: &GrayImage, destination: &mut GrayImage) {
+ assert_eq!(source.len(), destination.len());
+
+ copy_border(source, destination);
+ sharpen_inner_pixels(source, destination);
+}
+
+fn copy_border(source: &GrayImage, destination: &mut GrayImage) {
+ let last_row = source.height() - 1;
+ for x in 0..source.width() {
+ destination[(x, 0)] = source[(x, 0)];
+ destination[(x, last_row)] = source[(x, last_row)];
}
-
- fn make_histogram(image: &GrayImage) -> GrayHistogram {
- let mut histogram = [0; 256];
- for pixel in image.pixels() {
- histogram[pixel.0[0] as usize] += 1;
- }
- histogram
+ let last_col = source.width() - 1;
+ for y in 0..source.height() {
+ destination[(0, y)] = source[(0, y)];
+ destination[(last_col, y)] = source[(last_col, y)];
}
+}
- fn determine_histogram_correction(
- image: &GrayImage,
- histogram: GrayHistogram,
- ) -> HistogramCorrection {
- let adjustment_pixels = image.len() / PIXEL_HEIGHT;
-
- let mut num_pixels = 0;
- let mut brightness = 0;
-
- let mincut = loop {
- num_pixels += histogram[brightness as usize];
- brightness += 1;
- if num_pixels >= adjustment_pixels {
- break u8::min(brightness, 20);
- }
- };
-
- let minshift = loop {
- num_pixels += histogram[brightness as usize];
- brightness += 1;
- if num_pixels >= 2 * adjustment_pixels {
- break u8::min(brightness, 64);
- }
- };
-
- brightness = u8::MAX;
- num_pixels = 0;
- let maxshift = loop {
- num_pixels += histogram[brightness as usize];
- brightness -= 1;
- if num_pixels >= 2 * adjustment_pixels {
- break u8::max(brightness, 192);
- }
- };
-
- let pre_offset = -(mincut as f32 / 2.);
- let post_offset = -(minshift as f32);
- let factor = (255.0 - post_offset) / maxshift as f32;
- HistogramCorrection {
- pre_offset,
- post_offset,
- factor,
- }
- }
-
- fn apply_histogram_correction(image: &mut GrayImage, correction: HistogramCorrection) {
- for pixel in image.pixels_mut() {
- let pixel = &mut pixel.0[0];
- let value = (*pixel as f32 + correction.pre_offset) * correction.factor
- + correction.post_offset;
- *pixel = value.clamp(0f32, u8::MAX as f32) as u8;
- }
- }
-
- pub fn median_brightness(image: &GrayImage) -> u8 {
- let histogram = Self::make_histogram(image);
- let midpoint = image.len() / 2;
-
- debug_assert_eq!(
- image.len(),
- histogram.iter().copied().map(usize::from).sum()
- );
-
- let mut num_pixels = 0;
- for brightness in u8::MIN..=u8::MAX {
- num_pixels += histogram[brightness as usize];
- if num_pixels >= midpoint {
- return brightness;
- }
- }
-
- unreachable!("Somehow less pixels where counted in the histogram than exist in the image")
- }
-
- pub fn blur(source: &GrayImage, destination: &mut GrayImage) {
- assert_eq!(source.len(), destination.len());
-
- Self::copy_border(source, destination);
- Self::blur_inner_pixels(source, destination);
- }
-
- pub fn sharpen(source: &GrayImage, destination: &mut GrayImage) {
- assert_eq!(source.len(), destination.len());
-
- Self::copy_border(source, destination);
- Self::sharpen_inner_pixels(source, destination);
- }
-
- fn copy_border(source: &GrayImage, destination: &mut GrayImage) {
- let last_row = source.height() -1;
- for x in 0..source.width() {
- destination[(x, 0)] = source[(x, 0)];
- destination[(x, last_row)] = source[(x, last_row)];
- }
- let last_col = source.width() - 1;
- for y in 0..source.height() {
- destination[(0, y)] = source[(0, y)];
- destination[(last_col, y)] = source[(last_col, y)];
- }
- }
-
- fn blur_inner_pixels(source: &GrayImage, destination: &mut GrayImage) {
- for y in 1..source.height() - 2 {
- for x in 1..source.width() - 2 {
- let weighted_sum = source.get_pixel(x - 1, y - 1).0[0] as u32
- + source.get_pixel(x, y - 1).0[0] as u32
- + source.get_pixel(x + 1, y - 1).0[0] as u32
- + source.get_pixel(x - 1, y).0[0] as u32
- + 8 * source.get_pixel(x, y).0[0] as u32
- + source.get_pixel(x + 1, y).0[0] as u32
- + source.get_pixel(x - 1, y + 1).0[0] as u32
- + source.get_pixel(x, y + 1).0[0] as u32
- + source.get_pixel(x + 1, y + 1).0[0] as u32;
- let blurred = weighted_sum / 16;
- destination.get_pixel_mut(x, y).0[0] = blurred.clamp(u8::MIN as u32, u8::MAX as u32) as u8;
- }
- }
- }
-
- fn sharpen_inner_pixels(source: &GrayImage, destination: &mut GrayImage) {
- for y in 1..source.height() - 2 {
- for x in 1..source.width() - 2 {
- let weighted_sum = -(source.get_pixel(x - 1, y - 1).0[0] as i32)
- - source.get_pixel(x, y - 1).0[0] as i32
- - source.get_pixel(x + 1, y - 1).0[0] as i32
- - source.get_pixel(x - 1, y).0[0] as i32
- + 9 * source.get_pixel(x, y).0[0] as i32
- - source.get_pixel(x + 1, y).0[0] as i32
- - source.get_pixel(x - 1, y + 1).0[0] as i32
- - source.get_pixel(x, y + 1).0[0] as i32
- - source.get_pixel(x + 1, y + 1).0[0] as i32;
- destination.get_pixel_mut(x, y).0[0] = weighted_sum.clamp(u8::MIN as i32, u8::MAX as i32) as u8;
- }
+fn blur_inner_pixels(source: &GrayImage, destination: &mut GrayImage) {
+ for y in 1..source.height() - 2 {
+ for x in 1..source.width() - 2 {
+ let weighted_sum = source.get_pixel(x - 1, y - 1).0[0] as u32
+ + source.get_pixel(x, y - 1).0[0] as u32
+ + source.get_pixel(x + 1, y - 1).0[0] as u32
+ + source.get_pixel(x - 1, y).0[0] as u32
+ + 8 * source.get_pixel(x, y).0[0] as u32
+ + source.get_pixel(x + 1, y).0[0] as u32
+ + source.get_pixel(x - 1, y + 1).0[0] as u32
+ + source.get_pixel(x, y + 1).0[0] as u32
+ + source.get_pixel(x + 1, y + 1).0[0] as u32;
+ let blurred = weighted_sum / 16;
+ destination.get_pixel_mut(x, y).0[0] =
+ blurred.clamp(u8::MIN as u32, u8::MAX as u32) as u8;
}
}
}
+
+fn sharpen_inner_pixels(source: &GrayImage, destination: &mut GrayImage) {
+ for y in 1..source.height() - 2 {
+ for x in 1..source.width() - 2 {
+ let weighted_sum = -(source.get_pixel(x - 1, y - 1).0[0] as i32)
+ - source.get_pixel(x, y - 1).0[0] as i32
+ - source.get_pixel(x + 1, y - 1).0[0] as i32
+ - source.get_pixel(x - 1, y).0[0] as i32
+ + 9 * source.get_pixel(x, y).0[0] as i32
+ - source.get_pixel(x + 1, y).0[0] as i32
+ - source.get_pixel(x - 1, y + 1).0[0] as i32
+ - source.get_pixel(x, y + 1).0[0] as i32
+ - source.get_pixel(x + 1, y + 1).0[0] as i32;
+ destination.get_pixel_mut(x, y).0[0] =
+ weighted_sum.clamp(u8::MIN as i32, u8::MAX as i32) as u8;
+ }
+ }
+}
+
+pub(crate) fn ostromoukhov_dither(source: GrayImage, bias: u8) -> Bitmap {
+ let width = source.width();
+ let height = source.height();
+ assert_eq!(width % 8, 0);
+
+ let mut source = source.into_raw();
+ let mut destination = BitVec::repeat(false, source.len());
+
+ for y in 0..height as usize {
+ let start = y * width as usize;
+ if y % 2 == 0 {
+ for x in 0..width as usize {
+ ostromoukhov_dither_pixel(
+ &mut source,
+ &mut destination,
+ start + x,
+ width as usize,
+ y == (height - 1) as usize,
+ 1,
+ bias,
+ );
+ }
+ } else {
+ for x in (0..width as usize).rev() {
+ ostromoukhov_dither_pixel(
+ &mut source,
+ &mut destination,
+ start + x,
+ width as usize,
+ y == (height - 1) as usize,
+ -1,
+ bias,
+ );
+ }
+ }
+ }
+
+ Bitmap::from_bitvec(width as usize, destination)
+}
+
+#[inline]
+fn ostromoukhov_dither_pixel(
+ source: &mut [u8],
+ destination: &mut BitVec,
+ position: usize,
+ width: usize,
+ last_row: bool,
+ direction: isize,
+ bias: u8,
+) {
+ let old_pixel = source[position];
+
+ let destination_value = old_pixel > bias;
+ destination.set(position, destination_value);
+
+ let error = if destination_value {
+ 255 - old_pixel
+ } else {
+ old_pixel
+ };
+
+ let mut diffuse = |to: usize, mat: i16| {
+ let diffuse_value = source[to] as i16 + mat;
+ source[to] = diffuse_value.clamp(u8::MIN.into(), u8::MAX.into()) as u8;
+ };
+
+ let lookup = if destination_value {
+ ERROR_DIFFUSION_MATRIX[error as usize].map(move |i| -i)
+ } else {
+ ERROR_DIFFUSION_MATRIX[error as usize]
+ };
+ diffuse((position as isize + direction) as usize, lookup[0]);
+
+ if !last_row {
+ diffuse(
+ ((position + width) as isize - direction) as usize,
+ lookup[1],
+ );
+ diffuse(((position + width) as isize) as usize, lookup[2]);
+ }
+}
+
+const ERROR_DIFFUSION_MATRIX: [[i16; 3]; 256] = [
+ [0, 1, 0],
+ [1, 0, 0],
+ [1, 0, 1],
+ [2, 0, 1],
+ [2, 0, 2],
+ [3, 0, 2],
+ [4, 0, 2],
+ [4, 1, 2],
+ [5, 1, 2],
+ [5, 2, 2],
+ [5, 3, 2],
+ [6, 3, 2],
+ [6, 3, 3],
+ [7, 3, 3],
+ [7, 4, 3],
+ [8, 4, 3],
+ [8, 5, 3],
+ [9, 5, 3],
+ [9, 5, 4],
+ [10, 6, 3],
+ [10, 6, 4],
+ [11, 7, 3],
+ [11, 7, 4],
+ [11, 8, 4],
+ [12, 7, 5],
+ [12, 7, 6],
+ [12, 7, 7],
+ [12, 7, 8],
+ [12, 7, 9],
+ [13, 7, 9],
+ [13, 7, 10],
+ [13, 7, 11],
+ [13, 7, 12],
+ [14, 7, 12],
+ [14, 8, 12],
+ [15, 8, 12],
+ [15, 9, 12],
+ [16, 9, 12],
+ [16, 10, 12],
+ [17, 10, 12],
+ [17, 11, 12],
+ [18, 12, 11],
+ [19, 12, 11],
+ [19, 13, 11],
+ [20, 13, 11],
+ [20, 14, 11],
+ [21, 15, 10],
+ [22, 15, 10],
+ [22, 17, 9],
+ [23, 17, 9],
+ [24, 18, 8],
+ [24, 19, 8],
+ [25, 19, 8],
+ [26, 20, 7],
+ [26, 21, 7],
+ [27, 22, 6],
+ [28, 23, 5],
+ [28, 24, 5],
+ [29, 25, 4],
+ [30, 26, 3],
+ [31, 26, 3],
+ [31, 28, 2],
+ [32, 28, 2],
+ [33, 29, 1],
+ [34, 30, 0],
+ [33, 31, 1],
+ [32, 33, 1],
+ [32, 33, 2],
+ [31, 34, 3],
+ [30, 36, 3],
+ [29, 37, 4],
+ [29, 37, 5],
+ [28, 39, 5],
+ [32, 34, 7],
+ [37, 29, 8],
+ [42, 23, 10],
+ [46, 19, 11],
+ [51, 13, 12],
+ [52, 14, 13],
+ [53, 13, 12],
+ [53, 14, 13],
+ [54, 14, 13],
+ [55, 14, 13],
+ [55, 14, 13],
+ [56, 15, 14],
+ [57, 14, 13],
+ [56, 15, 15],
+ [55, 17, 15],
+ [54, 18, 16],
+ [53, 20, 16],
+ [52, 21, 17],
+ [52, 22, 17],
+ [51, 24, 17],
+ [50, 25, 18],
+ [49, 27, 18],
+ [47, 29, 19],
+ [48, 29, 19],
+ [48, 29, 20],
+ [49, 29, 20],
+ [49, 30, 20],
+ [50, 31, 20],
+ [50, 31, 20],
+ [51, 31, 20],
+ [51, 31, 21],
+ [52, 31, 21],
+ [52, 32, 21],
+ [53, 32, 21],
+ [53, 32, 22],
+ [55, 32, 21],
+ [56, 31, 22],
+ [58, 31, 21],
+ [59, 30, 22],
+ [61, 30, 21],
+ [62, 29, 22],
+ [64, 29, 21],
+ [65, 28, 22],
+ [67, 28, 21],
+ [68, 27, 22],
+ [70, 27, 21],
+ [71, 26, 22],
+ [73, 26, 21],
+ [75, 25, 21],
+ [76, 25, 21],
+ [78, 24, 21],
+ [80, 23, 21],
+ [81, 23, 21],
+ [83, 22, 21],
+ [85, 21, 20],
+ [85, 22, 21],
+ [85, 22, 22],
+ [84, 24, 22],
+ [84, 24, 23],
+ [84, 25, 23],
+ [83, 27, 23],
+ [83, 28, 23],
+ [82, 29, 24],
+ [82, 30, 24],
+ [81, 31, 25],
+ [80, 32, 26],
+ [80, 33, 26],
+ [79, 35, 26],
+ [79, 36, 26],
+ [78, 37, 27],
+ [77, 38, 28],
+ [77, 39, 28],
+ [76, 41, 28],
+ [75, 42, 29],
+ [75, 43, 29],
+ [74, 44, 30],
+ [74, 45, 30],
+ [75, 46, 30],
+ [75, 46, 30],
+ [76, 46, 30],
+ [76, 46, 31],
+ [77, 46, 31],
+ [77, 47, 31],
+ [78, 47, 31],
+ [78, 47, 32],
+ [79, 47, 32],
+ [79, 48, 32],
+ [80, 49, 32],
+ [83, 46, 32],
+ [86, 44, 32],
+ [90, 42, 31],
+ [93, 40, 31],
+ [96, 39, 30],
+ [100, 36, 30],
+ [103, 35, 29],
+ [106, 33, 29],
+ [110, 30, 29],
+ [113, 29, 28],
+ [114, 29, 28],
+ [115, 29, 28],
+ [115, 29, 28],
+ [116, 30, 29],
+ [117, 29, 28],
+ [117, 30, 29],
+ [118, 30, 29],
+ [119, 30, 29],
+ [109, 43, 27],
+ [100, 57, 23],
+ [90, 71, 20],
+ [80, 85, 17],
+ [70, 99, 14],
+ [74, 98, 12],
+ [78, 97, 10],
+ [81, 96, 9],
+ [85, 95, 7],
+ [89, 94, 5],
+ [92, 93, 4],
+ [96, 92, 2],
+ [100, 91, 0],
+ [100, 90, 2],
+ [100, 88, 5],
+ [100, 87, 7],
+ [99, 86, 10],
+ [99, 85, 12],
+ [99, 84, 14],
+ [99, 82, 17],
+ [98, 81, 20],
+ [98, 80, 22],
+ [98, 79, 24],
+ [98, 77, 27],
+ [98, 76, 29],
+ [97, 75, 32],
+ [97, 73, 35],
+ [97, 72, 37],
+ [96, 71, 40],
+ [96, 69, 43],
+ [96, 67, 46],
+ [96, 66, 48],
+ [95, 65, 51],
+ [95, 63, 54],
+ [95, 61, 57],
+ [94, 60, 60],
+ [94, 58, 63],
+ [94, 57, 65],
+ [93, 55, 69],
+ [93, 54, 71],
+ [93, 52, 74],
+ [92, 51, 77],
+ [92, 49, 80],
+ [91, 47, 84],
+ [91, 46, 86],
+ [93, 49, 82],
+ [96, 52, 77],
+ [98, 55, 73],
+ [101, 58, 68],
+ [104, 61, 63],
+ [106, 65, 58],
+ [109, 68, 53],
+ [111, 71, 49],
+ [114, 74, 44],
+ [116, 78, 39],
+ [118, 76, 40],
+ [119, 74, 42],
+ [120, 73, 43],
+ [122, 71, 44],
+ [123, 69, 46],
+ [124, 67, 48],
+ [125, 66, 49],
+ [127, 64, 50],
+ [128, 62, 52],
+ [129, 60, 54],
+ [131, 58, 55],
+ [132, 57, 56],
+ [136, 47, 63],
+ [139, 38, 70],
+ [143, 29, 76],
+ [147, 19, 83],
+ [151, 9, 90],
+ [154, 0, 97],
+ [160, 0, 92],
+ [171, 0, 82],
+ [183, 0, 71],
+ [184, 0, 71],
+];
diff --git a/src/stream_window.rs b/src/stream_window.rs
index 0358c61..6975ebf 100644
--- a/src/stream_window.rs
+++ b/src/stream_window.rs
@@ -1,7 +1,7 @@
use crate::cli::StreamScreenOptions;
-use crate::ledwand_dither::{LedwandDither, LedwandDitherOptions};
+use crate::ledwand_dither::*;
use image::{
- imageops::{dither, resize, BiLevel, FilterType},
+ imageops::{resize, FilterType},
DynamicImage, ImageBuffer, Luma, Rgb, Rgba,
};
use log::{error, info, warn};
@@ -11,42 +11,31 @@ use scap::{
frame::Frame,
};
use servicepoint::{
- Bitmap, Command, CompressionCode, Connection, Origin, FRAME_PACING, PIXEL_HEIGHT, PIXEL_WIDTH,
+ Command, CompressionCode, Connection, Origin, FRAME_PACING, PIXEL_HEIGHT, PIXEL_WIDTH,
};
use std::time::Duration;
pub fn stream_window(connection: &Connection, options: StreamScreenOptions) {
info!("Starting capture with options: {:?}", options);
- warn!("this implementation does not drop any frames - set a lower fps or disable dithering if your computer cannot keep up.");
let capturer = match start_capture(&options) {
Some(value) => value,
None => return,
};
- let mut bitmap = Bitmap::new(PIXEL_WIDTH, PIXEL_HEIGHT);
info!("now starting to stream images");
loop {
let mut frame = get_next_frame(&capturer);
- LedwandDither::histogram_correction(&mut frame);
+ histogram_correction(&mut frame);
let mut orig = frame.clone();
- LedwandDither::blur(&orig, &mut frame);
+ blur(&orig, &mut frame);
std::mem::swap(&mut frame, &mut orig);
- LedwandDither::sharpen(&orig, &mut frame);
+ sharpen(&orig, &mut frame);
- let cutoff = if options.no_dither {
- LedwandDither::median_brightness(&frame)
- } else {
- dither(&mut frame, &BiLevel);
- u8::MAX / 2
- };
-
- for (mut dest, src) in bitmap.iter_mut().zip(frame.pixels()) {
- *dest = src.0[0] > cutoff;
- }
+ let bitmap = ostromoukhov_dither(frame, u8::MAX / 2);
connection
.send(Command::BitmapLinearWin(