def test_bitmap_not_available_error():
"""
Trigger LIQ_BITMAP_NOT_AVAILABLE and ensure that
liq.BitmapNotAvailableError is raised
"""
attr = liq.Attr()
hist = liq.Histogram(attr)
with pytest.raises(liq.BitmapNotAvailableError):
result = hist.quantize(attr)
def test_unsupported_error():
"""
Trigger LIQ_UNSUPPORTED and ensure that liq.UnsupportedError is
raised
"""
# A simple way of getting LIQ_UNSUPPORTED is adding more than 256
# fixed colors to a histogram
attr = liq.Attr()
hist = liq.Histogram(attr)
for i in range(256):
hist.add_fixed_color(liq.Color(i, 0, 0, 255), 0)
with pytest.raises(liq.UnsupportedError):
hist.add_fixed_color(liq.Color(255, 255, 0, 255), 0)
def test_histogram_add_fixed_color():
"""
Test Histogram.add_fixed_color
"""
width_A, height_A, input_pixels_A = utils.load_test_image('flower')
width_B, height_B, input_pixels_B = utils.load_test_image('flower-huechange-1')
assert width_A == width_B
width, height = width_A, height_A
attr = liq.Attr()
hist = liq.Histogram(attr)
image_A = attr.create_rgba(input_pixels_A, width, height, 0)
hist.add_image(attr, image_A)
image_B = attr.create_rgba(input_pixels_B, width, height, 0)
hist.add_image(attr, image_B)
FIXED_COLORS = [
liq.Color(255, 0, 0, 255), # red
liq.Color(0, 0, 255, 255), # blue
liq.Color(128, 0, 128, 255), # purple
liq.Color(255, 255, 0, 255), # yellow
]
for fixedColor in FIXED_COLORS:
hist.add_fixed_color(fixedColor, 0)
result = hist.quantize(attr)
result_palette = result.get_palette()
# Check that we have a decently-sized palette
assert len(result_palette) > 128
# Try remapping both images -- make sure we don't get an exception
# or something
result.remap_image(image_A)
result.remap_image(image_B)
# Check that the fixed colors are present in the output palette
for fixedColor in FIXED_COLORS:
assert fixedColor in result_palette
def test_histogram_basic():
"""
Basic test of Histogram:
- __init__()
- add_image()
- quantize()
"""
# Testing with three input images
width_A, height_A, input_pixels_A = utils.load_test_image('flower')
width_B, height_B, input_pixels_B = utils.load_test_image('flower-huechange-1')
width_C, height_C, input_pixels_C = utils.load_test_image('flower-huechange-2')
assert width_A == width_B == width_C
assert height_A == height_B == height_C
width, height = width_A, height_A
attr = liq.Attr()
hist = liq.Histogram(attr)
image_A = attr.create_rgba(input_pixels_A, width, height, 0)
hist.add_image(attr, image_A)
image_B = attr.create_rgba(input_pixels_B, width, height, 0)
hist.add_image(attr, image_B)
image_C = attr.create_rgba(input_pixels_C, width, height, 0)
hist.add_image(attr, image_C)
result = hist.quantize(attr)
# Check that we have a decently-sized palette
assert len(result.get_palette()) > 128
# Try remapping all three images -- make sure we don't get an
# exception or something
result.remap_image(image_A)
result.remap_image(image_B)
result.remap_image(image_C)
def test_histogram_add_colors():
"""
Test Histogram.add_colors(), as well as the HistogramEntry class
"""
# First, quantize flower-huechange-1.jpg on its own
width, height, input_pixels = utils.load_test_image('flower-huechange-1')
attr = liq.Attr()
other_image = attr.create_rgba(input_pixels, width, height, 0)
result = other_image.quantize(attr)
result_pixels = result.remap_image(other_image)
result_palette = result.get_palette()
# ~
# Create a list of HistogramEntrys for it
entries = []
for i, color in enumerate(result_palette):
count = result_pixels.count(i)
entry = liq.HistogramEntry(color, count)
entries.append(entry)
# Test HistogramEntry getters
assert entry.color == color
assert entry.count == count
# Test setters
entry.color = result_palette[0]
entry.count = 50
assert entry.color == result_palette[0]
assert entry.count == 50
# (Set properties back to what they should be)
entry.color = color
entry.count = count
assert entries
# ~
# Set up a Histogram
attr = liq.Attr()
hist = liq.Histogram(attr)
# Add flower.jpg as an image
width, height, input_pixels = utils.load_test_image('flower')
image = attr.create_rgba(input_pixels, width, height, 0)
hist.add_image(attr, image)
# Add the HistogramEntrys for flower-huechange-1.jpg
hist.add_colors(attr, entries, 0)
# And quantize
result = hist.quantize(attr)
# ~
# Check that we have a decently-sized palette
assert len(result.get_palette()) > 128
# Try remapping both images -- make sure we don't get an exception
# or something
result.remap_image(image)
result.remap_image(other_image)