remove spacers in image processing

src/cli.rs

@@ -151,6 +151,9 @@ pub struct ImageProcessingOptions {
         help = "Disable dithering. Brightness will be adjusted so that around half of the pixels are on."
     )]
     pub no_dither: bool,
+
+    #[arg(long, help = "Do not remove the spacers from the image.")]
+    pub no_spacers: bool,
 }
 
 #[derive(clap::Parser, std::fmt::Debug, Clone)]

src/image_processing.rs

@@ -6,32 +6,57 @@ use image::{
     imageops::{resize, FilterType},
     DynamicImage, ImageBuffer, Luma,
 };
-use servicepoint::{Bitmap, PIXEL_HEIGHT, PIXEL_WIDTH};
+use log::{debug, trace};
+use servicepoint::{Bitmap, Grid, PIXEL_HEIGHT, PIXEL_WIDTH, TILE_HEIGHT, TILE_SIZE};
+use std::time::Instant;
 
+#[derive(Debug)]
 pub struct ImageProcessingPipeline {
     options: ImageProcessingOptions,
 }
 
+const SPACER_HEIGHT: usize = TILE_SIZE / 2;
+const PIXEL_HEIGHT_INCLUDING_SPACERS: usize = SPACER_HEIGHT * (TILE_HEIGHT - 1) + PIXEL_HEIGHT;
+
 impl ImageProcessingPipeline {
     pub fn new(options: ImageProcessingOptions) -> Self {
+        debug!("Creating image pipeline: {:?}", options);
         Self { options }
     }
 
     pub fn process(&self, frame: DynamicImage) -> Bitmap {
-        let frame = Self::resize_grayscale(&frame);
+        let start_time = Instant::now();
+
+        let frame = self.resize_grayscale(frame);
         let frame = self.grayscale_processing(frame);
-        self.grayscale_to_bitmap(frame)
+        let mut result = self.grayscale_to_bitmap(frame);
+
+        if !self.options.no_spacers {
+            result = Self::remove_spacers(result);
+        }
+
+        trace!("image processing took {:?}", start_time.elapsed());
+        result
     }
 
-    fn resize_grayscale(frame: &DynamicImage) -> ImageBuffer<Luma<u8>, Vec<u8>> {
+    fn resize_grayscale(&self, frame: DynamicImage) -> ImageBuffer<Luma<u8>, Vec<u8>> {
+        // TODO: keep aspect ratio
+        // TODO: make it work for non-maximum sizes
+
         let frame = frame.grayscale().to_luma8();
-        let frame = resize(
+
+        let target_height = if self.options.no_spacers {
+            PIXEL_HEIGHT
+        } else {
+            PIXEL_HEIGHT_INCLUDING_SPACERS
+        };
+
+        resize(
             &frame,
             PIXEL_WIDTH as u32,
-            PIXEL_HEIGHT as u32,
+            target_height as u32,
             FilterType::Nearest,
-        );
-        frame
+        )
     }
 
     fn grayscale_processing(
@@ -65,4 +90,23 @@ impl ImageProcessingPipeline {
             ostromoukhov_dither(orig, u8::MAX / 2)
         }
     }
+
+    fn remove_spacers(bitmap: Bitmap) -> Bitmap {
+        let mut result = Bitmap::max_sized();
+
+        let mut source_y = 0;
+        for result_y in 0..result.height() {
+            if result_y != 0 && result_y % TILE_SIZE == 0 {
+                source_y += 4;
+            }
+
+            for x in 0..result.width() {
+                result.set(x, result_y, bitmap.get(x, source_y));
+            }
+
+            source_y += 1;
+        }
+
+        result
+    }
 }

src/pixels.rs

@@ -53,4 +53,5 @@ fn pixels_image(
             CompressionCode::default(),
         ))
         .expect("failed to send image command");
+    info!("sent image to display");
 }

src/stream_window.rs

@@ -1,5 +1,7 @@
-use crate::cli::{ImageProcessingOptions, StreamScreenOptions};
-use crate::image_processing::ImageProcessingPipeline;
+use crate::{
+    cli::{ImageProcessingOptions, StreamScreenOptions},
+    image_processing::ImageProcessingPipeline,
+};
 use image::{DynamicImage, ImageBuffer, Rgb, Rgba};
 use log::{error, info, warn};
 use scap::{
@@ -7,15 +9,9 @@ use scap::{
     frame::convert_bgra_to_rgb,
     frame::Frame,
 };
-use servicepoint::{
-    Command, CompressionCode, Connection, Origin, FRAME_PACING, PIXEL_HEIGHT, TILE_HEIGHT,
-    TILE_SIZE,
-};
+use servicepoint::{Command, CompressionCode, Connection, Origin, FRAME_PACING};
 use std::time::Duration;
 
-const SPACER_HEIGHT: usize = TILE_SIZE / 2;
-const PIXEL_HEIGHT_INCLUDING_SPACERS: usize = SPACER_HEIGHT * (TILE_HEIGHT - 1) + PIXEL_HEIGHT;
-
 pub fn stream_window(
     connection: &Connection,
     options: StreamScreenOptions,