Android中图片压缩方案详解及源码下载

private Bitmap compressImage(Bitmap image) { 
 ByteArrayOutputStream baos = new ByteArrayOutputStream(); 
 image.compress(Bitmap.CompressFormat.JPEG, 100, baos);//质量压缩方法，这里100表示不压缩，把压缩后的数据存放到baos中 
 int options = 100; 
 while ( baos.toByteArray().length / 1024>100) { //循环判断如果压缩后图片是否大于100kb,大于继续压缩 
 baos.reset();//重置baos即清空baos 
 image.compress(Bitmap.CompressFormat.JPEG, options, baos);//这里压缩options%，把压缩后的数据存放到baos中 
 options -= 10;//每次都减少10 
 } 
 ByteArrayInputStream isBm = new ByteArrayInputStream(baos.toByteArray());//把压缩后的数据baos存放到ByteArrayInputStream中 
 Bitmap bitmap = BitmapFactory.decodeStream(isBm, null, null);//把ByteArrayInputStream数据生成图片 
 return bitmap; 
 }

private Bitmap getimage(String srcPath) { 
 BitmapFactory.Options newOpts = new BitmapFactory.Options(); 
 //开始读入图片，此时把options.inJustDecodeBounds 设回true了 
 newOpts.inJustDecodeBounds = true; 
 Bitmap bitmap = BitmapFactory.decodeFile(srcPath,newOpts);//此时返回bm为空 
 newOpts.inJustDecodeBounds = false; 
 int w = newOpts.outWidth; 
 int h = newOpts.outHeight; 
 //现在主流手机比较多是1280*720分辨率，所以高和宽我们设置为 
 float hh = 1280f;//这里设置高度为1280f 
 float ww = 720f;//这里设置宽度为720f 
 //缩放比。由于是固定比例缩放，只用高或者宽其中一个数据进行计算即可 
 int be = 1;//be=1表示不缩放 
 if (w > h && w > ww) {//如果宽度大的话根据宽度固定大小缩放 
 be = (int) (newOpts.outWidth / ww); 
 } else if (w < h && h > hh) {//如果高度高的话根据宽度固定大小缩放 
 be = (int) (newOpts.outHeight / hh); 
 } 
 if (be <= 0) 
 be = 1; 
 newOpts.inSampleSize = be;//设置缩放比例 
 //重新读入图片，注意此时已经把options.inJustDecodeBounds 设回false了 
 bitmap = BitmapFactory.decodeFile(srcPath, newOpts); 
 return compressImage(bitmap);//压缩好比例大小后再进行质量压缩 
 }

public static void compressBitmapToFile(Bitmap bmp, File file){
 // 尺寸压缩倍数,值越大，图片尺寸越小
 int ratio = 2;
 // 压缩Bitmap到对应尺寸
 Bitmap result = Bitmap.createBitmap(bmp.getWidth() / ratio, bmp.getHeight() / ratio, Config.ARGB_8888);
 Canvas canvas = new Canvas(result);
 Rect rect = new Rect(0, 0, bmp.getWidth() / ratio, bmp.getHeight() / ratio);
 canvas.drawBitmap(bmp, null, rect, null);

 ByteArrayOutputStream baos = new ByteArrayOutputStream();
 // 把压缩后的数据存放到baos中
 result.compress(Bitmap.CompressFormat.JPEG, 100 ,baos);
 try { 
 FileOutputStream fos = new FileOutputStream(file); 
 fos.write(baos.toByteArray()); 
 fos.flush(); 
 fos.close(); 
 } catch (Exception e) { 
 e.printStackTrace(); 
 } 
}

ByteArrayOutputStream out = new ByteArrayOutputStream(); 
image.compress(Bitmap.CompressFormat.JPEG, 85, out); 
float zoom = (float)Math.sqrt(size * 1024 / (float)out.toByteArray().length); 

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

Bitmap result = Bitmap.createBitmap(image, 0, 0, image.getWidth(), image.getHeight(), matrix, true); 

out.reset(); 
result.compress(Bitmap.CompressFormat.JPEG, 85, out); 
while(out.toByteArray().length > size * 1024){ 
 System.out.println(out.toByteArray().length); 
 matrix.setScale(0.9f, 0.9f); 
 result = Bitmap.createBitmap(result, 0, 0, result.getWidth(), result.getHeight(), matrix, true); 
 out.reset(); 
 result.compress(Bitmap.CompressFormat.JPEG, 85, out); 
}

jstring Java_net_bither_util_NativeUtil_compressBitmap(JNIEnv* env,
 jobject thiz, jobject bitmapcolor, int w, int h, int quality,
 jbyteArray fileNameStr, jboolean optimize) {

 AndroidBitmapInfo infocolor;
 BYTE* pixelscolor;
 int ret;
 BYTE * data;
 BYTE *tmpdata;
 char * fileName = jstrinTostring(env, fileNameStr);
 if ((ret = AndroidBitmap_getInfo(env, bitmapcolor, &infocolor)) < 0) {
 LOGE("AndroidBitmap_getInfo() failed ! error=%d", ret);
 return (*env)->NewStringUTF(env, "0");;
 }
 if ((ret = AndroidBitmap_lockPixels(env, bitmapcolor, &pixelscolor)) < 0) {
 LOGE("AndroidBitmap_lockPixels() failed ! error=%d", ret);
 }

 BYTE r, g, b;
 data = NULL;
 data = malloc(w * h * 3);
 tmpdata = data;
 int j = 0, i = 0;
 int color;
 for (i = 0; i < h; i++) {
 for (j = 0; j < w; j++) {
 color = *((int *) pixelscolor);
 r = ((color & 0x00FF0000) >> 16);
 g = ((color & 0x0000FF00) >> 8);
 b = color & 0x000000FF;
 *data = b;
 *(data + 1) = g;
 *(data + 2) = r;
 data = data + 3;
 pixelscolor += 4;

 }

 }
 AndroidBitmap_unlockPixels(env, bitmapcolor);
 int resultCode= generateJPEG(tmpdata, w, h, quality, fileName, optimize);
 free(tmpdata);
 if(resultCode==0){
 jstring result=(*env)->NewStringUTF(env, error);
 error=NULL;
 return result;
 }
 return (*env)->NewStringUTF(env, "1"); //success
}

/**
 * 计算缩放比
 * @param bitWidth 当前图片宽度
 * @param bitHeight 当前图片高度
 * @return int 缩放比
 */
 public static int getRatioSize(int bitWidth, int bitHeight) {
 // 图片最大分辨率
 int imageHeight = 1280;
 int imageWidth = 960;
 // 缩放比
 int ratio = 1;
 // 缩放比,由于是固定比例缩放，只用高或者宽其中一个数据进行计算即可
 if (bitWidth > bitHeight && bitWidth > imageWidth) {
 // 如果图片宽度比高度大,以宽度为基准
 ratio = bitWidth / imageWidth;
 } else if (bitWidth < bitHeight && bitHeight > imageHeight) {
 // 如果图片高度比宽度大，以高度为基准
 ratio = bitHeight / imageHeight;
 }
 // 最小比率为1
 if (ratio <= 0)
 ratio = 1;
 return ratio;
 }

/**
 * @Description: 通过JNI图片压缩把Bitmap保存到指定目录
 * @param curFilePath
 * 当前图片文件地址
 * @param targetFilePath
 * 要保存的图片文件地址
 */
 public static void compressBitmap(String curFilePath, String targetFilePath) {
 // 最大图片大小 500KB
 int maxSize = 500;
 //根据地址获取bitmap
 Bitmap result = getBitmapFromFile(curFilePath);
 ByteArrayOutputStream baos = new ByteArrayOutputStream();
 // 质量压缩方法，这里100表示不压缩，把压缩后的数据存放到baos中
 int quality = 100;
 result.compress(Bitmap.CompressFormat.JPEG, quality, baos);
 // 循环判断如果压缩后图片是否大于500kb,大于继续压缩
 while (baos.toByteArray().length / 1024 > maxSize) {
 // 重置baos即清空baos
 baos.reset();
 // 每次都减少10
 quality -= 10;
 // 这里压缩quality，把压缩后的数据存放到baos中
 result.compress(Bitmap.CompressFormat.JPEG, quality, baos);
 }
 // JNI保存图片到SD卡 这个关键
 NativeUtil.saveBitmap(result, quality, targetFilePath, true);
 // 释放Bitmap
 if (!result.isRecycled()) {
 result.recycle();
 }
 }

package net.bither.util;
import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.Rect;
import android.media.ExifInterface;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
/**
* JNI图片压缩工具类
*
* @Description TODO
* @Package net.bither.util
* @Class NativeUtil
*/
public class NativeUtil {

 private static int DEFAULT_QUALITY = 95;

 /**
 * @Description: JNI基本压缩
 * @param bit
 * bitmap对象
 * @param fileName
 * 指定保存目录名
 * @param optimize
 * 是否采用哈弗曼表数据计算 品质相差5-10倍
 */
 public static void compressBitmap(Bitmap bit, String fileName, boolean optimize) {
 saveBitmap(bit, DEFAULT_QUALITY, fileName, optimize);
 }

 /**
 * @Description: 通过JNI图片压缩把Bitmap保存到指定目录
 * @param image
 * bitmap对象
 * @param filePath
 * 要保存的指定目录
 */
 public static void compressBitmap(Bitmap image, String filePath) {
 // 最大图片大小 150KB
 int maxSize = 150;
 // 获取尺寸压缩倍数
 int ratio = NativeUtil.getRatioSize(image.getWidth(),image.getHeight());
 // 压缩Bitmap到对应尺寸
 Bitmap result = Bitmap.createBitmap(image.getWidth() / ratio,image.getHeight() / ratio, Config.ARGB_8888);
 Canvas canvas = new Canvas(result);
 Rect rect = new Rect(0, 0, image.getWidth() / ratio, image.getHeight() / ratio);
 canvas.drawBitmap(image,null,rect,null);
 ByteArrayOutputStream baos = new ByteArrayOutputStream();
 // 质量压缩方法，这里100表示不压缩，把压缩后的数据存放到baos中
 int options = 100;
 result.compress(Bitmap.CompressFormat.JPEG, options, baos);
 // 循环判断如果压缩后图片是否大于100kb,大于继续压缩
 while (baos.toByteArray().length / 1024 > maxSize) {
 // 重置baos即清空baos
 baos.reset();
 // 每次都减少10
 options -= 10;
 // 这里压缩options%，把压缩后的数据存放到baos中
 result.compress(Bitmap.CompressFormat.JPEG, options, baos);
 }
 // JNI保存图片到SD卡 这个关键
 NativeUtil.saveBitmap(result, options, filePath, true);
 // 释放Bitmap
 if (!result.isRecycled()) {
 result.recycle();
 }
 }

 /**
 * @Description: 通过JNI图片压缩把Bitmap保存到指定目录
 * @param curFilePath
 * 当前图片文件地址
 * @param targetFilePath
 * 要保存的图片文件地址
 */
 public static void compressBitmap(String curFilePath, String targetFilePath) {
 // 最大图片大小 500KB
 int maxSize = 500;
 //根据地址获取bitmap
 Bitmap result = getBitmapFromFile(curFilePath);
 ByteArrayOutputStream baos = new ByteArrayOutputStream();
 // 质量压缩方法，这里100表示不压缩，把压缩后的数据存放到baos中
 int quality = 100;
 result.compress(Bitmap.CompressFormat.JPEG, quality, baos);
 // 循环判断如果压缩后图片是否大于500kb,大于继续压缩
 while (baos.toByteArray().length / 1024 > maxSize) {
 // 重置baos即清空baos
 baos.reset();
 // 每次都减少10
 quality -= 10;
 // 这里压缩quality，把压缩后的数据存放到baos中
 result.compress(Bitmap.CompressFormat.JPEG, quality, baos);
 }
 // JNI保存图片到SD卡 这个关键
 NativeUtil.saveBitmap(result, quality, targetFilePath, true);
 // 释放Bitmap
 if (!result.isRecycled()) {
 result.recycle();
 }

 }

 /**
 * 计算缩放比
 * @param bitWidth 当前图片宽度
 * @param bitHeight 当前图片高度
 * @return int 缩放比
 */
 public static int getRatioSize(int bitWidth, int bitHeight) {
 // 图片最大分辨率
 int imageHeight = 1280;
 int imageWidth = 960;
 // 缩放比
 int ratio = 1;
 // 缩放比,由于是固定比例缩放，只用高或者宽其中一个数据进行计算即可
 if (bitWidth > bitHeight && bitWidth > imageWidth) {
 // 如果图片宽度比高度大,以宽度为基准
 ratio = bitWidth / imageWidth;
 } else if (bitWidth < bitHeight && bitHeight > imageHeight) {
 // 如果图片高度比宽度大，以高度为基准
 ratio = bitHeight / imageHeight;
 }
 // 最小比率为1
 if (ratio <= 0)
 ratio = 1;
 return ratio;
 }

 /**
 * 通过文件路径读获取Bitmap防止OOM以及解决图片旋转问题
 * @param filePath
 * @return
 */
 public static Bitmap getBitmapFromFile(String filePath){
 BitmapFactory.Options newOpts = new BitmapFactory.Options();
 newOpts.inJustDecodeBounds = true;//只读边,不读内容 
 BitmapFactory.decodeFile(filePath, newOpts);
 int w = newOpts.outWidth;
 int h = newOpts.outHeight;
 // 获取尺寸压缩倍数
 newOpts.inSampleSize = NativeUtil.getRatioSize(w,h);
 newOpts.inJustDecodeBounds = false;//读取所有内容
 newOpts.inDither = false;
 newOpts.inPurgeable=true;
 newOpts.inInputShareable=true;
 newOpts.inTempStorage = new byte[32 * 1024];
 Bitmap bitmap = null;
 File file = new File(filePath);
 FileInputStream fs = null;
 try {
 fs = new FileInputStream(file);
 } catch (FileNotFoundException e) {
 e.printStackTrace();
 }
 try {
 if(fs!=null){
 bitmap = BitmapFactory.decodeFileDescriptor(fs.getFD(),null,newOpts);
 //旋转图片
 int photoDegree = readPictureDegree(filePath);
 if(photoDegree != 0){
  Matrix matrix = new Matrix();
  matrix.postRotate(photoDegree);
  // 创建新的图片
  bitmap = Bitmap.createBitmap(bitmap, 0, 0,
  bitmap.getWidth(), bitmap.getHeight(), matrix, true);
 }
 }
 } catch (IOException e) {
 e.printStackTrace();
 } finally{
 if(fs!=null) {
 try {
  fs.close();
 } catch (IOException e) {
  e.printStackTrace();
 }
 }
 }
 return bitmap;
 }

 /**
 *
 * 读取图片属性：旋转的角度
 * @param path 图片绝对路径
 * @return degree旋转的角度
 */

 public static int readPictureDegree(String path) {
 int degree = 0;
 try {
 ExifInterface exifInterface = new ExifInterface(path);
 int orientation = exifInterface.getAttributeInt(
  ExifInterface.TAG_ORIENTATION,
  ExifInterface.ORIENTATION_NORMAL);
 switch (orientation) {
 case ExifInterface.ORIENTATION_ROTATE_90:
  degree = 90;
  break;
 case ExifInterface.ORIENTATION_ROTATE_180:
  degree = 180;
  break;
 case ExifInterface.ORIENTATION_ROTATE_270:
  degree = 270;
  break;
 }
 } catch (IOException e) {
 e.printStackTrace();
 }
 return degree;
 }

 /**
 * 调用native方法
 * @Description:函数描述
 * @param bit
 * @param quality
 * @param fileName
 * @param optimize
 */
 private static void saveBitmap(Bitmap bit, int quality, String fileName, boolean optimize) {
 compressBitmap(bit, bit.getWidth(), bit.getHeight(), quality, fileName.getBytes(), optimize);
 }

 /**
 * 调用底层 bitherlibjni.c中的方法
 * @Description:函数描述
 * @param bit
 * @param w
 * @param h
 * @param quality
 * @param fileNameBytes
 * @param optimize
 * @return
 */
 private static native String compressBitmap(Bitmap bit, int w, int h, int quality, byte[] fileNameBytes,
   boolean optimize);
 /**
 * 加载lib下两个so文件
 */
 static {
 System.loadLibrary("jpegbither");
 System.loadLibrary("bitherjni");
 }
}

public void pickFromGallery() {
 if (Build.VERSION.SDK_INT < Build.VERSION_CODES.KITKAT) {
 startActivityForResult(new Intent(Intent.ACTION_GET_CONTENT).setType("image/*"),
 REQUEST_PICK_IMAGE);
 } else {
 Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
 intent.addCategory(Intent.CATEGORY_OPENABLE);
 intent.setType("image/*");
 startActivityForResult(intent, REQUEST_KITKAT_PICK_IMAGE);
 }
}

public static String getPathByUri(Context context, Uri data){
 if (Build.VERSION.SDK_INT < Build.VERSION_CODES.KITKAT) {
 return getPathByUri4BeforeKitkat(context, data);
 }else {
 return getPathByUri4AfterKitkat(context, data);
 }
 }
 //4.4以前通过Uri获取路径：data是Uri，filename是一个String的字符串，用来保存路径
 public static String getPathByUri4BeforeKitkat(Context context, Uri data) {
 String filename=null;
 if (data.getScheme().toString().compareTo("content") == 0) {
 Cursor cursor = context.getContentResolver().query(data, new String[] { "_data" }, null, null, null);
 if (cursor.moveToFirst()) {
 filename = cursor.getString(0);
 }
 } else if (data.getScheme().toString().compareTo("file") == 0) {// file:///开头的uri
 filename = data.toString().replace("file://", "");// 替换file://
 if (!filename.startsWith("/mnt")) {// 加上"/mnt"头
 filename += "/mnt";
 }
 }
 return filename;
 }
 //4.4以后根据Uri获取路径：
 @SuppressLint("NewApi")
 public static String getPathByUri4AfterKitkat(final Context context, final Uri uri) {
 final boolean isKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
 // DocumentProvider
 if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
 if (isExternalStorageDocument(uri)) {// ExternalStorageProvider
 final String docId = DocumentsContract.getDocumentId(uri);
 final String[] split = docId.split(":");
 final String type = split[0];
 if ("primary".equalsIgnoreCase(type)) {
  return Environment.getExternalStorageDirectory() + "/" + split[1];
 }
 } else if (isDownloadsDocument(uri)) {// DownloadsProvider
 final String id = DocumentsContract.getDocumentId(uri);
 final Uri contentUri = ContentUris.withAppendedId(Uri.parse("content://downloads/public_downloads"),
  Long.valueOf(id));
 return getDataColumn(context, contentUri, null, null);
 } else if (isMediaDocument(uri)) {// MediaProvider
 final String docId = DocumentsContract.getDocumentId(uri);
 final String[] split = docId.split(":");
 final String type = split[0];
 Uri contentUri = null;
 if ("image".equals(type)) {
  contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
 } else if ("video".equals(type)) {
  contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
 } else if ("audio".equals(type)) {
  contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
 }
 final String selection = "_id=?";
 final String[] selectionArgs = new String[] { split[1] };
 return getDataColumn(context, contentUri, selection, selectionArgs);
 }
 } else if ("content".equalsIgnoreCase(uri.getScheme())) {// MediaStore
 // (and
 // general)
 return getDataColumn(context, uri, null, null);
 } else if ("file".equalsIgnoreCase(uri.getScheme())) {// File
 return uri.getPath();
 }
 return null;
 }

 /**
 * Get the value of the data column for this Uri. This is useful for
 * MediaStore Uris, and other file-based ContentProviders.
 *
 * @param context
 * The context.
 * @param uri
 * The Uri to query.
 * @param selection
 * (Optional) Filter used in the query.
 * @param selectionArgs
 * (Optional) Selection arguments used in the query.
 * @return The value of the _data column, which is typically a file path.
 */
 public static String getDataColumn(Context context, Uri uri, String selection, String[] selectionArgs) {
 Cursor cursor = null;
 final String column = "_data";
 final String[] projection = { column };
 try {
 cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs, null);
 if (cursor != null && cursor.moveToFirst()) {
 final int column_index = cursor.getColumnIndexOrThrow(column);
 return cursor.getString(column_index);
 }
 } finally {
 if (cursor != null)
 cursor.close();
 }
 return null;
 }

 /**
 * @param uri
 * The Uri to check.
 * @return Whether the Uri authority is ExternalStorageProvider.
 */
 public static boolean isExternalStorageDocument(Uri uri) {
 return "com.android.externalstorage.documents".equals(uri.getAuthority());
 }

 /**
 * @param uri
 * The Uri to check.
 * @return Whether the Uri authority is DownloadsProvider.
 */
 public static boolean isDownloadsDocument(Uri uri) {
 return "com.android.providers.downloads.documents".equals(uri.getAuthority());
 }

 /**
 * @param uri
 * The Uri to check.
 * @return Whether the Uri authority is MediaProvider.
 */
 public static boolean isMediaDocument(Uri uri) {
 return "com.android.providers.media.documents".equals(uri.getAuthority());
 }