diff options
Diffstat (limited to 'poezio/colors.py')
| -rw-r--r-- | poezio/colors.py | 39 |
1 files changed, 8 insertions, 31 deletions
diff --git a/poezio/colors.py b/poezio/colors.py index 6bbbb12e..c1019145 100644 --- a/poezio/colors.py +++ b/poezio/colors.py @@ -3,6 +3,8 @@ import curses import hashlib import math +from . import hsluv + Palette = Dict[float, int] # BT.601 (YCbCr) constants, see XEP-0392 @@ -33,13 +35,6 @@ def ncurses_color_to_rgb(color: int) -> Tuple[float, float, float]: return r / 5, g / 5, b / 5 -def rgb_to_ycbcr(r: float, g: float, b: float) -> Tuple[float, float, float]: - y = K_R * r + K_G * g + K_B * b - cr = (r - y) / (1 - K_R) / 2 - cb = (b - y) / (1 - K_B) / 2 - return y, cb, cr - - def generate_ccg_palette(curses_palette: List[int], reference_y: float) -> Palette: cbcr_palette = {} # type: Dict[float, Tuple[float, int]] @@ -48,8 +43,10 @@ def generate_ccg_palette(curses_palette: List[int], # drop grayscale if r == g == b: continue - y, cb, cr = rgb_to_ycbcr(r, g, b) - key = round(cbcr_to_angle(cb, cr), 2) + h, _, y = hsluv.rgb_to_hsluv((r, g, b)) + # this is to keep the code compatible with earlier versions of XEP-0392 + y = y / 100 + key = round(h) try: existing_y, *_ = cbcr_palette[key] except KeyError: @@ -68,35 +65,15 @@ def text_to_angle(text: str) -> float: hf = hashlib.sha1() hf.update(text.encode("utf-8")) hue = int.from_bytes(hf.digest()[:2], "little") - return hue / 65535 * math.pi * 2 - - -def angle_to_cbcr_edge(angle: float) -> Tuple[float, float]: - cr = math.sin(angle) - cb = math.cos(angle) - if abs(cr) > abs(cb): - factor = 0.5 / abs(cr) - else: - factor = 0.5 / abs(cb) - return cb * factor, cr * factor - - -def cbcr_to_angle(cb: float, cr: float) -> float: - magn = math.sqrt(cb**2 + cr**2) - if magn > 0: - cr /= magn - cb /= magn - return math.atan2(cr, cb) % (2 * math.pi) + return hue / 65535 * 360 def ccg_palette_lookup(palette: Palette, angle: float) -> int: # try quick lookup first try: - color = palette[round(angle, 2)] + return palette[round(angle)] except KeyError: pass - else: - return color best_metric = float("inf") best = None |