Tune print quality defaults: density 2, font 30pt, threshold 160

- Default density to thick (2) for bolder output
- Default font size to 30pt for better readability
- Add draw.fontmode="1" to disable antialiasing for crisp 1-bit text
- Add ImageOps.autocontrast before thresholding images
- Update web GUI defaults to match CLI

fichero/cli.py

@@ -157,17 +157,17 @@ def main() -> None:
 
     p_text = sub.add_parser("text", help="Print text label")
     p_text.add_argument("text", nargs="+", help="Text to print")
-    p_text.add_argument("--density", type=int, default=1, choices=[0, 1, 2],
+    p_text.add_argument("--density", type=int, default=2, choices=[0, 1, 2],
                         help="Print density: 0=light, 1=medium, 2=thick")
     p_text.add_argument("--copies", type=int, default=1, help="Number of copies")
-    p_text.add_argument("--font-size", type=int, default=24, help="Font size in points")
+    p_text.add_argument("--font-size", type=int, default=30, help="Font size in points")
     p_text.add_argument("--label-height", type=int, default=240,
                         help="Label height in pixels (default: 240)")
     p_text.set_defaults(func=cmd_text)
 
     p_image = sub.add_parser("image", help="Print image file")
     p_image.add_argument("path", help="Path to image file")
-    p_image.add_argument("--density", type=int, default=1, choices=[0, 1, 2],
+    p_image.add_argument("--density", type=int, default=2, choices=[0, 1, 2],
                          help="Print density: 0=light, 1=medium, 2=thick")
     p_image.add_argument("--copies", type=int, default=1, help="Number of copies")
     p_image.set_defaults(func=cmd_image)

fichero/imaging.py

@@ -2,7 +2,7 @@
 
 import logging
 
-from PIL import Image, ImageDraw, ImageFont
+from PIL import Image, ImageDraw, ImageFont, ImageOps
 
 from fichero.printer import PRINTHEAD_PX
 
@@ -18,6 +18,7 @@ def prepare_image(img: Image.Image, max_rows: int = 240) -> Image.Image:
         log.warning("Image height %dpx exceeds max %dpx, cropping bottom", new_h, max_rows)
         new_h = max_rows
     img = img.resize((PRINTHEAD_PX, new_h), Image.LANCZOS)
+    img = ImageOps.autocontrast(img, cutoff=1)
     img = img.point(lambda x: 1 if x < 128 else 0, "1")
     return img
 
@@ -31,12 +32,13 @@ def image_to_raster(img: Image.Image) -> bytes:
     return img.tobytes()
 
 
-def text_to_image(text: str, font_size: int = 24, label_height: int = 240) -> Image.Image:
-    """Render text in landscape, then rotate 90 degrees for label printing."""
+def text_to_image(text: str, font_size: int = 30, label_height: int = 240) -> Image.Image:
+    """Render crisp 1-bit text, rotated 90 degrees for label printing."""
     canvas_w = label_height
     canvas_h = PRINTHEAD_PX
     img = Image.new("L", (canvas_w, canvas_h), 255)
     draw = ImageDraw.Draw(img)
+    draw.fontmode = "1"  # disable antialiasing - pure 1-bit glyph rendering
 
     font = ImageFont.load_default(size=font_size)
 

web/index.html

@@ -287,8 +287,8 @@
       <textarea id="textInput" placeholder="Type your label text..." rows="2">Hello</textarea>
       <div class="range-row">
         <label>Font size</label>
-        <input type="range" id="fontSize" min="10" max="72" value="24">
-        <span id="fontSizeVal">24</span>
+        <input type="range" id="fontSize" min="10" max="72" value="30">
+        <span id="fontSizeVal">30</span>
       </div>
       <div class="preview-wrap">
         <canvas id="textPreview"></canvas>
@@ -331,8 +331,8 @@
         <label>Density</label>
         <select id="density">
           <option value="0">Light</option>
-          <option value="1" selected>Medium</option>
-          <option value="2">Thick</option>
+          <option value="1">Medium</option>
+          <option value="2" selected>Thick</option>
         </select>
       </div>
       <div class="setting-item">
@@ -663,7 +663,7 @@ function threshold(canvas) {
   for (let i = 0; i < px.length; i += 4) {
     // Grayscale via luminance
     const gray = 0.299 * px[i] + 0.587 * px[i + 1] + 0.114 * px[i + 2];
-    const bw = gray < 128 ? 0 : 255;
+    const bw = gray < 160 ? 0 : 255;
     px[i] = px[i + 1] = px[i + 2] = bw;
     px[i + 3] = 255;
   }