backend: Add colorthief.py

pywal/__main__.py

@@ -36,6 +36,10 @@ def get_args(args):
     arg.add_argument("-b", metavar="background",
                      help="Custom background color to use.")
 
+    arg.add_argument("--backend", metavar="backend",
+                     help="Which color backend to use.",
+                     const="wal", type=str, nargs="?", default="wal")
+
     arg.add_argument("-c", action="store_true",
                      help="Delete all cached colorschemes.")
 
@@ -120,7 +124,8 @@ def process_args(args):
 
     if args.i:
         image_file = image.get(args.i)
-        colors_plain = colors.generate(image_file, light=args.l)
+        colors_plain = colors.generate(img=image_file, light=args.l,
+                                       backend=args.backend)
 
     if args.f:
         colors_plain = colors.file(args.f)

pywal/backends/__init__.py

@@ -9,8 +9,10 @@
 Created by Dylan Araps.
 """
 
+from . import colorthief
 from . import wal
 
 __all__ = [
+    "colorthief",
     "wal",
 ]

pywal/backends/colorthief.py

@@ -0,0 +1,64 @@
+"""
+Generate a colorscheme using ColorThief.
+"""
+import sys
+
+from colorthief import ColorThief
+
+from .. import util
+from ..settings import COLOR_COUNT
+
+
+def create_palette(img, colors):
+    """Create palette."""
+    raw_colors = colors[:1] + colors[8:16] + colors[8:-1]
+
+    # Modify colors to make a better scheme.
+    raw_colors[0] = util.darken_color(colors[0], 0.80)
+    raw_colors[15] = util.lighten_color(colors[15], 0.80)
+    raw_colors[7] = raw_colors[15]
+
+    colors = {"wallpaper": img, "alpha": util.Color.alpha_num,
+              "special": {}, "colors": {}}
+
+    for i, color in enumerate(raw_colors):
+        colors["colors"]["color%s" % i] = util.lighten_color(color, 0.25)
+
+    raw_colors[8] = util.blend_color(raw_colors[0], raw_colors[15])
+
+    colors["colors"]["color0"] = raw_colors[0]
+    colors["special"]["background"] = raw_colors[0]
+    colors["special"]["foreground"] = raw_colors[15]
+    colors["special"]["cursor"] = raw_colors[1]
+
+    return colors
+
+
+def gen_colors(img, color_count):
+    """Loop until 16 colors are generated."""
+    color_thief = ColorThief(img)
+    color_cmd = color_thief.get_palette
+
+    for i in range(0, 20, 1):
+        raw_colors = color_cmd(color_count=color_count + i)
+
+        if len(raw_colors) > 16:
+            break
+
+        elif i == 19:
+            print("colors: ColorThief couldn't generate a suitable scheme",
+                  "for the image. Exiting...")
+            sys.exit(1)
+
+        else:
+            print("colors: ColorThief couldn't generate a %s color palette, "
+                  "trying a larger palette size %s."
+                  % (color_count, color_count + i))
+
+    return [util.rgb_to_hex(color) for color in raw_colors]
+
+
+def get(img, color_count=COLOR_COUNT, light=False):
+    """Get colorscheme."""
+    colors = gen_colors(img, color_count)
+    return create_palette(img, colors)

pywal/colors.py

@@ -12,6 +12,7 @@ from .settings import CACHE_DIR, COLOR_COUNT, __cache_version__
 def get(backend_type="wal"):
     """Get backend function name from name."""
     return {
+        "colorthief": backends.colorthief.get,
         "wal": backends.wal.get,
     }.get(backend_type, backend_type)