压缩100k图片不失真的方法；先获取图片的原始长度和宽度；然后计算图片的缩放值；最后等比例压缩；
下面代码是压缩的工具类；
public class PictureUtil {
/**
* 主方法
*
* @param filePath
* @return
*/
public static InputStream bitmapToString(String filePath) {
Bitmap bm = getSmallBitmap(filePath);
ByteArrayOutputStream baos = new ByteArrayOutputStream();
bm.compress(Bitmap.CompressFormat.JPEG, 60, baos);
// 把压缩后的数据baos存放到ByteArrayInputStream中
ByteArrayInputStream isBm = new ByteArrayInputStream(
baos.toByteArray());
return isBm;
}
/**
* 计算图片的缩放值
*
* @param options
* @param reqWidth
* @param reqHeight
* @return
*/
public static int calculateInSampleSize(BitmapFactory.Options options,
int reqWidth, int reqHeight) {
// Raw height and width of image
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > reqHeight || width > reqWidth) {
// Calculate ratios of height and width to requested height and
// width
final int heightRatio = Math.round((float) height
/ (float) reqHeight);
final int widthRatio = Math.round((float) width / (float) reqWidth);
// Choose the smallest ratio as inSampleSize value, this will
// guarantee
// a final image with both dimensions larger than or equal to the
// requested height and width.
inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;
}
return inSampleSize;
}
/**
* 根据路径获得突破并压缩返回bitmap用于显示
*
* @param imagesrc
* @return
*/
public static Bitmap getSmallBitmap(String filePath) {
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFile(filePath, options);
// Calculate inSampleSize
options.inSampleSize = calculateInSampleSize(options, 800, 480);
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
return BitmapFactory.decodeFile(filePath, options);
}
/**
* 根据路径删除图片
*
* @param path
*/
public static void deleteTempFile(String path) {
File file = new File(path);
if (file.exists()) {
file.delete();
}
}
/**
* 添加到图库
*/
public static void galleryAddPic(Context context, String path) {
Intent mediaScanIntent = new Intent(
Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
File f = new File(path);
Uri contentUri = Uri.fromFile(f);
mediaScanIntent.setData(contentUri);
context.sendBroadcast(mediaScanIntent);
}
/**
* 获取保存图片的目录
*
* @return
*/
public static File getAlbumDir() {
File dir = new File(
Environment
.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES),
getAlbumName());
if (!dir.exists()) {
dir.mkdirs();
}
return dir;
}
/**
* 获取保存 隐患检查的图片文件夹名称
*
* @return
*/
public static String getAlbumName() {
return "sheguantong";
}
}
下面是上传图片的工具类；只需要提供图片url就可以了；
**
*
* 上传工具类上传压缩；
* @author spring sky
* Email:[email protected]
* QQ:840950105
* MyName:石明政
*/
public class UploadUtil {
private static final String TAG = "uploadFile";
private static final int TIME_OUT = 10*1000; //超时时间
private static final String CHARSET = "utf-8"; //设置编码
/**
* android上传文件到服务器
* @param file 需要上传的文件
* @param RequestURL 请求的rul
* @return 返回响应的内容
*/
public static String uploadFile(String file,String RequestURL)
{
String result = null;
String BOUNDARY = UUID.randomUUID().toString(); //边界标识 随机生成
String PREFIX = "--" , LINE_END = "\r\n";
String CONTENT_TYPE = "multipart/form-data"; //内容类型
try {
URL url = new URL(RequestURL);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(TIME_OUT);
conn.setConnectTimeout(TIME_OUT);
conn.setDoInput(true); //允许输入流
conn.setDoOutput(true); //允许输出流
conn.setUseCaches(false); //不允许使用缓存
conn.setRequestMethod("POST"); //请求方式
conn.setRequestProperty("Charset", CHARSET); //设置编码
conn.setRequestProperty("connection", "keep-alive");
conn.setRequestProperty("Content-Type", CONTENT_TYPE + ";boundary=" + BOUNDARY);
if(file!=null){
/**
* 当文件不为空，把文件包装并且上传
*/
DataOutputStream dos = new DataOutputStream(conn.getOutputStream());
InputStream is =PictureUtil.bitmapToString(file);
byte[] bytes = new byte[9000];
int len = 0;
while((len=is.read(bytes))!=-1){
dos.write(bytes, 0, len);
}
is.close();
dos.write(LINE_END.getBytes());
byte[] end_data = (PREFIX+BOUNDARY+PREFIX+LINE_END).getBytes();
dos.write(end_data);
dos.flush();
/**
* 获取响应码 200=成功
* 当响应成功，获取响应的流
*/
int res = conn.getResponseCode();
Log.e(TAG, "response code:"+res);
// if(res==200)
// {
Log.e(TAG, "request success");
InputStream input = conn.getInputStream();
StringBuffer sb1= new StringBuffer();
int ss ;
while((ss=input.read())!=-1)
{
sb1.append((char)ss);
}
result = sb1.toString();
Log.e(TAG, "result : "+ result);
// }
// else{
// Log.e(TAG, "request error");
// }
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return result;
}
public static InputStream compressImage(String file) {
Bitmap bitmap = BitmapFactory.decodeFile(file);
BitmapFactory.Options newOpts = new BitmapFactory.Options();
// 开始读入图片，此时把options.inJustDecodeBounds设为true
newOpts.inJustDecodeBounds = true;
bitmap = BitmapFactory.decodeFile(file, newOpts);
newOpts.inJustDecodeBounds = false;
int w = newOpts.outWidth;
int h = newOpts.outHeight;
// 设置分辨率
float hh = 800f;
float ww = 400f;
// 缩放比。由于是固定的比例缩放，只用高或者宽其中一个数据进行计算即可
int be = 1;
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) {// 如果宽度大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newOpts.inJustDecodeBounds = false
bitmap = BitmapFactory.decodeFile(file, newOpts);
try {
// Bitmap bitmapyas=compressImage1(bitmap);
return compressImage2(bitmap);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
return null;
}
}
public static InputStream compressImage2(Bitmap bitmap) throws Exception {
try {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.JPEG, 100, baos);
int options = 100;
int size = baos.toByteArray().length / 1024;
while (size > 40 && options > 0) {
baos.reset();// 重置baos即清空baos
options -=10;// 每次都减少10
// 这里压缩options%，把压缩后的数据存放到baos中
bitmap.compress(Bitmap.CompressFormat.JPEG, options, baos);
size = baos.toByteArray().length / 1024;
}
// 把压缩后的数据baos存放到ByteArrayInputStream中
ByteArrayInputStream isBm = new ByteArrayInputStream(
baos.toByteArray());
return isBm;
} catch (Exception e) {
throw e;
}
}
}