使用 Camera.Parameters 调整亮度、对比度

Question

我正在尝试制作一个相机应用程序，但我找不到使用 Camera.Parameters 更改相机亮度和对比度的方法所以我的问题是如何将亮度和对比度功能添加到 increase/decrease brightness/contrast。例如，如果我增加 seekbarit 增加亮度。如果我减少搜索栏，它会降低亮度。请编辑我的代码或单独回答以帮助我。

package com.example.beautymaker;

import android.content.Context;

import android.graphics.Bitmap;
import android.graphics.Color;
import android.hardware.Camera;
import android.hardware.camera2.CameraCharacteristics;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;

import com.zomato.photofilters.imageprocessors.Filter;
import com.zomato.photofilters.imageprocessors.subfilters.BrightnessSubFilter;

import java.io.IOException;
import java.util.List;

public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {
    private SurfaceHolder mHolder;
    private Camera mCamera;

    public CameraPreview(Context context, Camera camera) {
        super(context);
        mCamera = camera;
        mHolder = getHolder();
        mHolder.addCallback(this);
        /*Camera.Parameters params = camera.getParameters();
        final int[] previewFpsRange = new int[2];
        params.getPreviewFpsRange(previewFpsRange);
        if (previewFpsRange[0] == previewFpsRange[1]) {
            final List<int[]> supportedFpsRanges = params.getSupportedPreviewFpsRange();
            for (int[] range : supportedFpsRanges) {
                if (range[0] != range[1]) {
                    params.setPreviewFpsRange(range[0], range[1]);
                    break;
                }
            }
        }*/



        // deprecated setting, but required on Android versions prior to 3.0
        mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

    }

    public void surfaceCreated(SurfaceHolder holder) {
        try {
            // create the surface and start camera preview
            if (mCamera == null) {
                mCamera.setPreviewDisplay(holder);
                mCamera.startPreview();


            }
        } catch (IOException e) {
            Log.d(VIEW_LOG_TAG, "Error setting camera preview: " + e.getMessage());
        }
    }

    public void refreshCamera(Camera camera) {
        if (mHolder.getSurface() == null) {
            // preview surface does not exist
            return;
        }
        // stop preview before making changes
        try {
            mCamera.stopPreview();
        } catch (Exception e) {
            // ignore: tried to stop a non-existent preview
        }
        // set preview size and make any resize, rotate or
        // reformatting changes here
        // start preview with new settings
        setCamera;
        try {
            mCamera.setPreviewDisplay(mHolder);
            mCamera.startPreview();
        } catch (Exception e) {
            Log.d(VIEW_LOG_TAG, "Error starting camera preview: " + e.getMessage());
        }
    }

    public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
        // If your preview can change or rotate, take care of those events here.
        // Make sure to stop the preview before resizing or reformatting it.
        refreshCamera(mCamera);
    }

    public void setCamera(Camera camera) {
        //method to set a camera instance

        mCamera = camera;
        Camera.Parameters parameters = mCamera.getParameters();


//        parameters.setPreviewFpsRange(1500,3000);

        parameters.setExposureCompensation(parameters.getMaxExposureCompensation());

        if(parameters.isAutoExposureLockSupported())
        {
            parameters.setAutoExposureLock(false);
        }

//        parameters.setColorEffect(Camera.Parameters.WHITE_BALANCE_INCANDESCENT);
        parameters.getAutoExposureLock();
        parameters.set("iso",50);
//                parameters.setWhiteBalance();
        parameters.setAutoWhiteBalanceLock(true);
        parameters.setWhiteBalance(Camera.Parameters.WHITE_BALANCE_SHADE);



        /*Filter filter = new Filter();
        filter.addSubFilter(new BrightnessSubFilter(parameters));*/

        mCamera.setParameters(parameters);



    }

    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {
        // TODO Auto-generated method stub
        // mCamera.release();

    }

    //for brightness
    public static Bitmap doBrightness(Bitmap src, int value) {
        // image size
        int width = src.getWidth();
        int height = src.getHeight();
        // create output bitmap
        Bitmap bmOut = Bitmap.createBitmap(width, height, src.getConfig());
        // color information
        int A, R, G, B;
        int pixel;

        // scan through all pixels
        for(int x = 0; x < width; ++x) {
            for(int y = 0; y < height; ++y) {
                // get pixel color
                pixel = src.getPixel(x, y);
                A = Color.alpha(pixel);
                R = Color.red(pixel);
                G = Color.green(pixel);
                B = Color.blue(pixel);

                // increase/decrease each channel
                R += value;
                if(R > 255) { R = 255; }
                else if(R < 0) { R = 0; }

                G += value;
                if(G > 255) { G = 255; }
                else if(G < 0) { G = 0; }

                B += value;
                if(B > 255) { B = 255; }
                else if(B < 0) { B = 0; }

                // apply new pixel color to output bitmap
                bmOut.setPixel(x, y, Color.argb(A, R, G, B));
            }
        }

        // return final image
        return bmOut;
    }
}

Answer 1

Camera.Parameters 中没有实现此目的的方法。您必须阅读此 documentation 以了解此 class 以检查可用参数，此 class 在 API 21 及更高版本中已弃用。

使用 Camera.Parameters 调整亮度、对比度

Adjust Brightness, Contrast using Camera.Parameters

camera-api