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# Exposure
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Image intensity and exposure adjustment operations for enhancing image contrast, brightness, and visibility. Includes histogram operations, gamma correction, and adaptive enhancement methods.
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## Capabilities
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### Histogram Operations
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```python { .api }
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def histogram(image, nbins=256, source_range='image', normalize=False):
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    """Calculate image histogram."""
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def equalize_hist(image, nbins=256, mask=None):
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    """Global histogram equalization."""
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def equalize_adapthist(image, kernel_size=None, clip_limit=0.01, nbins=256):
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    """Adaptive histogram equalization (CLAHE)."""
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def match_histograms(image, reference, multichannel=False, channel_axis=None):
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    """Match image histogram to reference."""
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def cumulative_distribution(image, nbins=256):
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    """Compute cumulative distribution function."""
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```
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### Intensity Adjustment
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```python { .api }
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def rescale_intensity(image, in_range='image', out_range='dtype'):
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    """Rescale image intensity values."""
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def adjust_gamma(image, gamma=1, gain=1):
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    """Apply gamma correction."""
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def adjust_sigmoid(image, cutoff=0.5, gain=10, inv=False):
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    """Apply sigmoid intensity adjustment."""
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def adjust_log(image, gain=1, inv=False):
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    """Apply logarithmic intensity adjustment."""
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```
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### Quality Assessment
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```python { .api }
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def is_low_contrast(image, fraction_threshold=0.05, lower_percentile=1, upper_percentile=99, method='linear'):
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    """Check if image has low contrast."""
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```
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## Types
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```python { .api }
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from numpy.typing import NDArray
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import numpy as np
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Histogram = NDArray[np.integer]
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IntensityRange = tuple
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GammaValue = float
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```