41 lines
997 B
Python
41 lines
997 B
Python
"""EOTF（PQ / ST.2084）相关纯算法。"""
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import numpy as np
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def calculate_pq_curve(gray_levels):
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"""计算 PQ (ST.2084) EOTF 理想曲线。
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Args:
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gray_levels: 灰阶百分比数组 (0-100)
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Returns:
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numpy.ndarray: 归一化亮度数组 (0-1)
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"""
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# PQ 曲线参数（ITU-R BT.2100 标准）
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m1 = 0.1593017578125 # = 2610 / 16384
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m2 = 78.84375 # = 78.84375
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c1 = 0.8359375 # = 3424 / 4096
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c2 = 18.8515625 # = 2413 / 128
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c3 = 18.6875 # = 2392 / 128
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L_bar = []
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for gray in gray_levels:
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V = gray / 100.0
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if V <= 0:
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L_bar.append(0)
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else:
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V_pow = np.power(V, 1 / m2)
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numerator = max(V_pow - c1, 0)
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denominator = c2 - c3 * V_pow
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if denominator > 0:
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L = np.power(numerator / denominator, 1 / m1)
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else:
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L = 0
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L_bar.append(L)
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return np.array(L_bar)
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