/**
 * 質(zhì)量壓縮
 *
 * @param format  圖片格式 jpeg,png,webp
 * @param quality 圖片的質(zhì)量,0-100,數(shù)值越小質(zhì)量越差
 */
public static void compress(Bitmap.CompressFormat format, int quality) {
    File sdFile = Environment.getExternalStorageDirectory();
    File originFile = new File(sdFile, "originImg.jpg");
    Bitmap originBitmap = BitmapFactory.decodeFile(originFile.getAbsolutePath());
    ByteArrayOutputStream bos = new ByteArrayOutputStream();
    originBitmap.compress(format, quality, bos);
    try {
        FileOutputStream fos = new FileOutputStream(new File(sdFile, "resultImg.jpg"));
        fos.write(bos.toByteArray());
        fos.flush();
        fos.close();
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
}

/**
 * 
 * @param inSampleSize  可以根據(jù)需求計算出合理的inSampleSize
 */
public static void compress(int inSampleSize) {
    File sdFile = Environment.getExternalStorageDirectory();
    File originFile = new File(sdFile, "originImg.jpg");
    BitmapFactory.Options options = new BitmapFactory.Options();
    //設(shè)置此參數(shù)是僅僅讀取圖片的寬高到options中，不會將整張圖片讀到內(nèi)存中，防止oom
    options.inJustDecodeBounds = true;
    Bitmap emptyBitmap = BitmapFactory.decodeFile(originFile.getAbsolutePath(), options);

    options.inJustDecodeBounds = false;
    options.inSampleSize = inSampleSize;
    Bitmap resultBitmap = BitmapFactory.decodeFile(originFile.getAbsolutePath(), options);
    ByteArrayOutputStream bos = new ByteArrayOutputStream();
    resultBitmap.compress(Bitmap.CompressFormat.JPEG, 100, bos);
    try {
        FileOutputStream fos = new FileOutputStream(new File(sdFile, "resultImg.jpg"));
        fos.write(bos.toByteArray());
        fos.flush();
        fos.close();
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
}

 /**
     *  縮放bitmap
     * @param context
     * @param id
     * @param maxW
     * @param maxH
     * @return
     */
    public static Bitmap resizeBitmap(Context context,int id,int maxW,int maxH,boolean hasAlpha,Bitmap reusable){
        Resources resources = context.getResources();
        BitmapFactory.Options options = new BitmapFactory.Options();
        // 只解碼出 outxxx參數(shù) 比如 寬、高
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeResource(resources,id,options);
        //根據(jù)寬、高進行縮放
        int w = options.outWidth;
        int h = options.outHeight;
        //設(shè)置縮放系數(shù)
        options.inSampleSize = calcuteInSampleSize(w,h,maxW,maxH);
        if (!hasAlpha){
            options.inPreferredConfig = Bitmap.Config.RGB_565;
        }
        options.inJustDecodeBounds = false;
        //設(shè)置成能復(fù)用
        options.inMutable=true;
        options.inBitmap=reusable;
        return BitmapFactory.decodeResource(resources,id,options);
    }

    /**
     * 計算縮放系數(shù)
     * @param w
     * @param h
     * @param maxW
     * @param maxH
     * @return 縮放的系數(shù)
     */
    private static int calcuteInSampleSize(int w,int h,int maxW,int maxH) {
        int inSampleSize = 1;
        if (w > maxW && h > maxH){
            inSampleSize = 2;
            //循環(huán) 使寬、高小于 最大的寬、高
            while (w /inSampleSize > maxW && h / inSampleSize > maxH){
                inSampleSize *= 2;
            }
        }
        return inSampleSize;
    }
}

void write_JPEG_file(uint8_t *data, int w, int h, jint q, const char *path) {
//    3.1、創(chuàng)建jpeg壓縮對象
    jpeg_compress_struct jcs;
    //錯誤回調(diào)
    jpeg_error_mgr error;
    jcs.err = jpeg_std_error(&error);
    //創(chuàng)建壓縮對象
    jpeg_create_compress(&jcs);
//    3.2、指定存儲文件  write binary
    FILE *f = fopen(path, "wb");
    jpeg_stdio_dest(&jcs, f);
//    3.3、設(shè)置壓縮參數(shù)
    jcs.image_width = w;
    jcs.image_height = h;
    //bgr
    jcs.input_components = 3;
    jcs.in_color_space = JCS_RGB;
    jpeg_set_defaults(&jcs);
    //開啟哈夫曼功能
    jcs.optimize_coding = true;
    jpeg_set_quality(&jcs, q, 1);
//    3.4、開始壓縮
    jpeg_start_compress(&jcs, 1);
//    3.5、循環(huán)寫入每一行數(shù)據(jù)
    int row_stride = w * 3;//一行的字節(jié)數(shù)
    JSAMPROW row[1];
    while (jcs.next_scanline < jcs.image_height) {
        //取一行數(shù)據(jù)
        uint8_t *pixels = data + jcs.next_scanline * row_stride;
        row[0]=pixels;
        jpeg_write_scanlines(&jcs,row,1);
    }
//    3.6、壓縮完成
    jpeg_finish_compress(&jcs);
//    3.7、釋放jpeg對象
    fclose(f);
    jpeg_destroy_compress(&jcs);
}

   BitmapFactory.Options options = new BitmapFactory.Options();
        // 只解碼出 outxxx參數(shù) 比如 寬、高
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeResource(resources,id,options);
        //根據(jù)寬、高進行縮放
        int w = options.outWidth;
        int h = options.outHeight;
        //設(shè)置縮放系數(shù)
        options.inSampleSize = calcuteInSampleSize(w,h,maxW,maxH);
        if (!hasAlpha){
            options.inPreferredConfig = Bitmap.Config.RGB_565;
        }
        options.inJustDecodeBounds = false;
        //設(shè)置成能復(fù)用
        options.inMutable=true;
        options.inBitmap=reusable;