Class SharpenOp

java.lang.Object
cloud.opencode.base.image.filter.SharpenOp
public final class SharpenOp extends Object
Unsharp Mask Sharpening Filter 非锐化掩模锐化滤波器

Enhances image edges using unsharp masking: result = src + amount * (src - blur). The blur is computed via GaussianBlurOp with a configurable sigma.

使用非锐化掩模增强图像边缘：result = src + amount * (src - blur)。 模糊通过 GaussianBlurOp 以可配置的 sigma 计算。

Features | 主要功能:

  • Unsharp mask sharpening with configurable amount and sigma - 可配置强度和 sigma 的非锐化掩模锐化
  • Default parameters: amount=1.0, sigma=1.0 - 默认参数：amount=1.0, sigma=1.0
  • Per-channel processing with clamping to [0, 255] - 逐通道处理并钳制到 [0, 255]
  • Alpha channel preservation - Alpha 通道保持不变

Usage Examples | 使用示例:

// Default sharpening (amount=1.0, sigma=1.0)
BufferedImage sharpened = SharpenOp.apply(image);

// Custom amount
BufferedImage sharpened = SharpenOp.apply(image, 1.5);

// Custom amount and sigma
BufferedImage sharpened = SharpenOp.apply(image, 2.0, 2.0);

Performance | 性能特性:

  • Time: O(w * h * k) dominated by Gaussian blur - 时间: O(w * h * k) 由高斯模糊主导
  • Space: O(w * h) - 空间: O(w * h)

Security | 安全性:

  • Thread-safe: Yes (stateless) - 线程安全: 是（无状态）
Since:
JDK 25, opencode-base-image V2.0.0
Author:
Leon Soo www.LeonSoo.com
See Also:

  • Method Details

    • apply

      public static BufferedImage apply(BufferedImage image)
      Apply unsharp mask sharpening with default parameters (amount=1.0, sigma=1.0). 使用默认参数（amount=1.0, sigma=1.0）应用非锐化掩模锐化。
      Parameters:
      image - the source image | 源图像
      Returns:
      the sharpened image | 锐化后的图像
      Throws:
      NullPointerException - if image is null | 当图像为 null 时抛出

    • apply

      public static BufferedImage apply(BufferedImage image, double amount)
      Apply unsharp mask sharpening with custom amount and default sigma=1.0. 使用自定义强度和默认 sigma=1.0 应用非锐化掩模锐化。
      Parameters:
      image - the source image | 源图像
      amount - the sharpening amount (must be >= 0) | 锐化强度（必须 >= 0）
      Returns:
      the sharpened image | 锐化后的图像
      Throws:
      NullPointerException - if image is null | 当图像为 null 时抛出
      ImageOperationException - if amount is negative, NaN, or infinite | 当 amount 为负数、NaN 或无穷时抛出

    • apply

      public static BufferedImage apply(BufferedImage image, double amount, double sigma)
      Apply unsharp mask sharpening with custom amount and sigma. 使用自定义强度和 sigma 应用非锐化掩模锐化。

      The algorithm computes: result = clamp(src + amount * (src - blur)), where blur = GaussianBlurOp.apply(image, sigma).

      算法计算：result = clamp(src + amount * (src - blur))， 其中 blur = GaussianBlurOp.apply(image, sigma)。

      Parameters:
      image - the source image | 源图像
      amount - the sharpening amount (must be >= 0) | 锐化强度（必须 >= 0）
      sigma - the Gaussian blur sigma (must be > 0) | 高斯模糊 sigma（必须大于 0）
      Returns:
      the sharpened image | 锐化后的图像
      Throws:
      NullPointerException - if image is null | 当图像为 null 时抛出
      ImageOperationException - if amount is negative or sigma is not positive | 当 amount 为负数或 sigma 不为正数时抛出