assistant-android/app/src/main/java/com/gh/common/util/BitmapUtils.java

package com.gh.common.util;

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.PixelFormat;
import android.graphics.drawable.Drawable;
import android.media.ExifInterface;

import java.io.BufferedOutputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

/**
 * Created by LGT on 2016/10/21.
 */
public class BitmapUtils {

    /**
     * 保存图片
     *
     * @param newPath
     * @param filePath
     * @return
     */
    public static boolean savePicture(String newPath, String filePath) {
        BitmapFactory.Options options = new BitmapFactory.Options();
//        options.inSampleSize = 2;
        Bitmap bitmap = BitmapFactory.decodeFile(filePath, options);

        File file = new File(newPath);
        int quality = 80;
        do {
            try {
                BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(file));
                bitmap.compress(Bitmap.CompressFormat.JPEG, quality, bos);
                bos.flush();
                bos.close();
            } catch (IOException e) {
                file.delete();
                e.printStackTrace();
                return false;
            }
            quality -= 10;
            if (quality < 10) {
                quality = 10;
            }
        } while (file.length() > 81920 && quality > 10);
        return true;
    }

    /**
     * 保存图片
     *
     * @param newPath
     * @param filePath
     * @return
     */

    // TODO 应该根据图片分辨率大小 采取不同的压缩方式 （质量/分辨率）
    public static boolean savePicture(String newPath, String filePath, int compressSize) {
        BitmapFactory.Options options = new BitmapFactory.Options();
        Bitmap bitmap = BitmapFactory.decodeFile(filePath, options);

        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        bitmap.compress(Bitmap.CompressFormat.JPEG, 85, bos);
        float zoom = (float) Math.sqrt(compressSize / (float) bos.toByteArray().length);

        Matrix matrix = new Matrix();
        matrix.setScale(zoom, zoom);

        Bitmap result = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true);
        bos.reset();

        result.compress(Bitmap.CompressFormat.JPEG, 85, bos);

        while (bos.toByteArray().length > compressSize) {
            matrix.setScale(0.9f, 0.9f);

            result = Bitmap.createBitmap(result, 0, 0, result.getWidth(), result.getHeight(), matrix, true);
            bos.reset();
            result.compress(Bitmap.CompressFormat.JPEG, 85, bos);
        }


        File file = new File(newPath);
        try {
            BufferedOutputStream fbos = new BufferedOutputStream(new FileOutputStream(file));
            result.compress(Bitmap.CompressFormat.JPEG, 85, fbos);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
            return false;
        }

        return true;
    }

    /**
     * 根据文件路径返回bitmap
     *
     * @param filepath 文件路径
     * @param w        宽
     * @param h        高
     * @return bitmap
     */
    public static Bitmap getBitmapByFile(String filepath, int w, int h) {
        try {
            BitmapFactory.Options options = new BitmapFactory.Options();
            // 设置为ture只获取图片大小
            options.inJustDecodeBounds = true;
            options.inPreferredConfig = Bitmap.Config.RGB_565;
            // 返回为空
            BitmapFactory.decodeFile(filepath, options);
            int width = options.outWidth;
            int height = options.outHeight;
            float scaleWidth = 0.f, scaleHeight = 0.f;
            if (width > w || height > h) {
                // 缩放
                scaleWidth = ((float) width) / w;
                scaleHeight = ((float) height) / h;
            }
            options.inJustDecodeBounds = false;
            int scale = (int) Math.ceil(Math.max(scaleWidth, scaleHeight));
            if (scale % 2 == 1) {
                scale += 1;
            }
            options.inSampleSize = scale;
            Bitmap bitmap = BitmapFactory.decodeFile(filepath, options);
            bitmap = rotatePicture(filepath, bitmap);
            if (bitmap != null) {
                return bitmap;
            }
            return null;
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }

    public static Bitmap rotatePicture(String path, Bitmap bitmap) {
        int rotate = 0;
        try {
            ExifInterface exifInterface = new ExifInterface(path);
            int orientation = exifInterface.getAttributeInt(
                    ExifInterface.TAG_ORIENTATION,
                    ExifInterface.ORIENTATION_NORMAL);
            switch (orientation) {
                case ExifInterface.ORIENTATION_ROTATE_90:
                    rotate = 90;
                    break;
                case ExifInterface.ORIENTATION_ROTATE_180:
                    rotate = 180;
                    break;
                case ExifInterface.ORIENTATION_ROTATE_270:
                    rotate = 270;
                    break;
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        if (rotate != 0) {
            Matrix matrix = new Matrix();
            matrix.setRotate(rotate);
            return Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(),
                    bitmap.getHeight(), matrix, true);
        } else {
            return bitmap;
        }
    }

    /**
     * Drawable转Bitmap
     */
    public static Bitmap drawableToBitmap(Drawable drawable) {
        if (drawable == null) {
            return null;
        }

        // 取 drawable 的长宽
        int w = drawable.getIntrinsicWidth();
        int h = drawable.getIntrinsicHeight();
        // 取 drawable 的颜色格式
        Bitmap.Config config = drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888
                : Bitmap.Config.RGB_565;
        //建立对应的Bitmap
        Bitmap bitmap = Bitmap.createBitmap(w, h, config);
        // 建立对应 bitmap 的画布
        Canvas canvas = new Canvas(bitmap);
        drawable.setBounds(0, 0, w, h);
        // 把 drawable 内容画到画布中
        drawable.draw(canvas);

        return bitmap;
    }

}