def extract_colors_from_files(max_colors=1, scale_by=0.5, color_space=ColorSpace.LAB,
palette_name="xkcd_49", fail_silently=True, *args):
""" Returns color: [files] mapping for a given set of files.
Allows to specify many files for examination (*args).
:param palette_name: colors palette name used for examination (web, xkcd_49 or xkcd_full)
:param color_space: color space for which calculations are performed (either LAB or RGB)
:param max_colors: maximum number of colors in palette (can be less if less number of colors has been identified)
:param scale_by: ratio by which image is reduced before an examination, use this for optimization, number [0.0, 1.0]
:param fail_silently: tells if program should continue on image read errors
Returns JSON-formatted object mapping colors to a list of images used for examination.
"""
results = {}
# get palette by name
palette = PALETTES[palette_name]
for image_path in args:
try:
colors = api.extract_colors(image_path,
palette=palette,
max_colors=max_colors,
scale_by=scale_by,
color_space=color_space)
except IOError:
if not fail_silently:
raise
else:
for color in colors:
if color not in results:
results[color] = []
results[color].append(image_path)
return dumps(results)
def test_flag(self):
image_path = self._full_path("images/flag.jpg")
palette = extract_colors(image_path, max_colors=3)
self.assertEquals(palette, ["navy blue", "red", "white"])
def test_bag(self):
image_path = self._full_path("images/bag.jpg")
palette = extract_colors(image_path, max_colors=2)
self.assertEquals(palette, ["white", "salmon"])
def test_simple_black(self):
image_path = self._full_path("images/1x1/000000.jpg")
image_palette = extract_colors(image_path)
self.assertEquals(image_palette, ["black"])
def test_simple_white(self):
image_path = self._full_path("images/1x1/ffffff.jpg")
image_palette = extract_colors(image_path)
self.assertEquals(image_palette, ["white"])
def test_simple_red(self):
image_path = self._full_path("images/1x1/ff0000.jpg")
image_palette = extract_colors(image_path)
self.assertEquals(image_palette, ["red"])
def test_max_colors_3(self):
image_palette = extract_colors(self.EXAMPLE_IMAGE, max_colors=3)
self.assertEquals(len(image_palette), 3)
def test_simple_white(self):
image_path = self._full_path("images/1x1/ffffff.jpg")
image_palette = extract_colors(image_path)
self.assertEquals(image_palette, ["white"])
def test_scale_down_does_not_change_results_if_small(self):
palette_from_scale_1 = extract_colors(self.EXAMPLE_IMAGE, max_colors=4, scale_by=1.0)
palette_from_scale_2 = extract_colors(self.EXAMPLE_IMAGE, max_colors=4, scale_by=0.9)
self.assertEquals(palette_from_scale_1, palette_from_scale_2)
def test_valid_image(self):
image_palette = extract_colors(self.EXAMPLE_IMAGE)
self.assertTrue(image_palette)
def test_sign(self):
image_path = self._full_path("images/sign.jpg")
palette = extract_colors(image_path, max_colors=3)
self.assertEquals(palette, ["light blue", "orange", "black"])
def test_flag(self):
image_path = self._full_path("images/flag.jpg")
palette = extract_colors(image_path, max_colors=3)
self.assertEquals(palette, ["navy blue", "red", "white"])
def test_bag(self):
image_path = self._full_path("images/bag.jpg")
palette = extract_colors(image_path, max_colors=2)
self.assertEquals(palette, ["white", "salmon"])
def test_simple_black(self):
image_path = self._full_path("images/1x1/000000.jpg")
image_palette = extract_colors(image_path)
self.assertEquals(image_palette, ["black"])
def test_sign(self):
image_path = self._full_path("images/sign.jpg")
palette = extract_colors(image_path, max_colors=3)
self.assertEquals(palette, ["light blue", "orange", "black"])
def test_scale_change_results_if_significant(self):
palette_from_scale_1 = extract_colors(self.EXAMPLE_IMAGE, max_colors=4, scale_by=1.0)
palette_from_scale_2 = extract_colors(self.EXAMPLE_IMAGE, max_colors=4, scale_by=0.1)
self.assertNotEquals(palette_from_scale_1, palette_from_scale_2)
def test_simple_red(self):
image_path = self._full_path("images/1x1/ff0000.jpg")
image_palette = extract_colors(image_path)
self.assertEquals(image_palette, ["red"])