java - 图像亮度对比度搜索栏

Question

我正在开发一个应用程序，我想实现一些“过滤器”，如对比度/亮度/色调等。我想通过 seekbar valuechanged 完成所有这些更改。此处找到的所有示例对于通过搜索栏进行实时更改一点也不流畅，并且未针对 12mpxl 及以上的照片进行优化。我想要像 instagram 的手动调整这样的东西，非常流畅。感谢您的宝贵时间。

Answer 1

试试这个。您可以使用 ColorMatrix 调整亮度、对比度、色调等。

import android.graphics.ColorFilter;
import android.graphics.ColorMatrix;
import android.graphics.ColorMatrixColorFilter;

public class ColorFilterGenerator {

private static double DELTA_INDEX[] = {
        0, 0.01, 0.02, 0.04, 0.05, 0.06, 0.07, 0.08, 0.1, 0.11,
        0.12, 0.14, 0.15, 0.16, 0.17, 0.18, 0.20, 0.21, 0.22, 0.24,
        0.25, 0.27, 0.28, 0.30, 0.32, 0.34, 0.36, 0.38, 0.40, 0.42,
        0.44, 0.46, 0.48, 0.5, 0.53, 0.56, 0.59, 0.62, 0.65, 0.68,
        0.71, 0.74, 0.77, 0.80, 0.83, 0.86, 0.89, 0.92, 0.95, 0.98,
        1.0, 1.06, 1.12, 1.18, 1.24, 1.30, 1.36, 1.42, 1.48, 1.54,
        1.60, 1.66, 1.72, 1.78, 1.84, 1.90, 1.96, 2.0, 2.12, 2.25,
        2.37, 2.50, 2.62, 2.75, 2.87, 3.0, 3.2, 3.4, 3.6, 3.8,
        4.0, 4.3, 4.7, 4.9, 5.0, 5.5, 6.0, 6.5, 6.8, 7.0,
        7.3, 7.5, 7.8, 8.0, 8.4, 8.7, 9.0, 9.4, 9.6, 9.8,
        10.0
};

public static ColorFilter adjustHue(float value) {
    ColorMatrix cm = new ColorMatrix();

    adjustHue(cm, value);

    return new ColorMatrixColorFilter(cm);
}

public static ColorFilter adjustExposure(float value) {
    ColorMatrix cm = new ColorMatrix();

    adjustExposure(cm, value);

    return new ColorMatrixColorFilter(cm);
}

public static ColorFilter adjustTemperature(int r, int g, int b) {
    ColorMatrix cm = new ColorMatrix();

    adjustTemperature(cm, r, g, b);

    return new ColorMatrixColorFilter(cm);
}

public static ColorFilter adjustContrast(float value) {
    ColorMatrix cm = new ColorMatrix();

    //adjustContrast(cm, value);

    setContrast(cm, value);

    return new ColorMatrixColorFilter(cm);
}

public static ColorFilter adjustSaturation(int value) {
    ColorMatrix cm = new ColorMatrix();

    adjustSaturation(cm, value);

    return new ColorMatrixColorFilter(cm);
}

public static ColorFilter adjustBrightness(int value) {
    ColorMatrix cm = new ColorMatrix();

    adjustBrightness(cm, value);

    return new ColorMatrixColorFilter(cm);
}

public static void adjustHue(ColorMatrix cm, float value) {
    value = cleanValue(value, 180f) / 180f * (float) Math.PI;
    if (value == 0) {
        return;
    }
    float cosVal = (float) Math.cos(value);
    float sinVal = (float) Math.sin(value);
    float lumR = 0.213f;
    float lumG = 0.715f;
    float lumB = 0.072f;
    float[] mat = new float[]
            {
                    lumR + cosVal * (1 - lumR) + sinVal * (-lumR), lumG + cosVal * (-lumG) + sinVal * (-lumG), lumB + cosVal * (-lumB) + sinVal * (1 - lumB), 0, 0,
                    lumR + cosVal * (-lumR) + sinVal * (0.143f), lumG + cosVal * (1 - lumG) + sinVal * (0.140f), lumB + cosVal * (-lumB) + sinVal * (-0.283f), 0, 0,
                    lumR + cosVal * (-lumR) + sinVal * (-(1 - lumR)), lumG + cosVal * (-lumG) + sinVal * (lumG), lumB + cosVal * (1 - lumB) + sinVal * (lumB), 0, 0,
                    0f, 0f, 0f, 1f, 0f,
                    0f, 0f, 0f, 0f, 1f};
    cm.postConcat(new ColorMatrix(mat));
}

public static void adjustContrast(ColorMatrix cm, int value) {
    value = (int) cleanValue(value, 100);
    if (value == 0) {
        return;
    }
    float x;
    if (value < 0) {
        x = 127 + value / 100 * 127;
    } else {
        x = value % 1;
        if (x == 0) {
            x = (float) DELTA_INDEX[value];
        } else {
            //x = DELTA_INDEX[(p_val<<0)]; // this is how the IDE does it.
            x = (float) DELTA_INDEX[(value << 0)] * (1 - x) + (float) DELTA_INDEX[(value << 0) + 1] * x; // use linear interpolation for more granularity.
        }
        x = x * 127 + 127;
    }

    float[] mat = new float[]
            {
                    x / 127, 0, 0, 0, 0.5f * (127 - x),
                    0, x / 127, 0, 0, 0.5f * (127 - x),
                    0, 0, x / 127, 0, 0.5f * (127 - x),
                    0, 0, 0, 1, 0,
                    0, 0, 0, 0, 1
            };
    cm.postConcat(new ColorMatrix(mat));

}

private static void setContrast(ColorMatrix cm, float contrast) {
    float scale = contrast + 1.f;
    float translate = (-.5f * scale + .5f) * 255.f;
    cm.set(new float[]{
            scale, 0, 0, 0, translate,
            0, scale, 0, 0, translate,
            0, 0, scale, 0, translate,
            0, 0, 0, 1, 0});
}

public static void adjustSaturation(ColorMatrix cm, float value) {
    value = cleanValue(value, 100);
    if (value == 0) {
        return;
    }

    float x = 1 + ((value > 0) ? 3 * value / 100 : value / 100);
    float lumR = 0.3086f;
    float lumG = 0.6094f;
    float lumB = 0.0820f;

    float[] mat = new float[]
            {
                    lumR * (1 - x) + x, lumG * (1 - x), lumB * (1 - x), 0, 0,
                    lumR * (1 - x), lumG * (1 - x) + x, lumB * (1 - x), 0, 0,
                    lumR * (1 - x), lumG * (1 - x), lumB * (1 - x) + x, 0, 0,
                    0, 0, 0, 1, 0,
                    0, 0, 0, 0, 1
            };
    cm.postConcat(new ColorMatrix(mat));
}

public static void adjustBrightness(ColorMatrix cm, float value) {
    value = cleanValue(value, 100);
    if (value == 0) {
        return;
    }

    float[] mat = new float[]
            {
                    1, 0, 0, 0, value,
                    0, 1, 0, 0, value,
                    0, 0, 1, 0, value,
                    0, 0, 0, 1, 0,
                    0, 0, 0, 0, 1
            };
    cm.postConcat(new ColorMatrix(mat));
}

public static void adjustTemperature(ColorMatrix cm, int r, int g, int b) {

    cm.set(new float[]{
            r / 255.0f, 0, 0, 0, 0,
            0, g / 255.0f, 0, 0, 0,
            0, 0, b / 255.0f, 0, 0,
            0, 0, 0, 1, 0});
}

public static void adjustExposure(ColorMatrix cm, float value) {
    value = cleanValue(value, 100);
//        if (value == 0) {
//            return;
//        }
//
//        float[] mat = new float[]
//                {
//                        value, 0, 0, 0, 0,
//                        0, value, 0, 0, 0,
//                        0, 0, value, 0, 0,
//                        0, 0, 0, 1, 0,
//                };
//        cm.postConcat(new ColorMatrix(mat));
     cm.set(new float[]{
            value, 0, 0, 0, 0,
            0, value, 0, 0, 0,
            0, 0, value, 0, 0,
            0, 0, 0, 1, 0,
    });
}

protected static float cleanValue(float p_val, float p_limit) {
    return Math.min(p_limit, Math.max(-p_limit, p_val));
}
}

只需在 onProgressChanged 中使用它。例如-

 mainImageView.setColorFilter(ColorFilterGenerator.adjustContrast(progress));