android - How whatsapp/Instagram or other compresses the image before uploading it to server? -

i used below method compress image before uploading server.

to summarize below code, take image phone/sdcard, convert bitmap , carryout scaling , compression on bitmap. save compressed bitmap on disk image in new location.

this method compress image 3mb - 5mb in 30-100kb. (when check compressed image size on sdcard)

then send newly compressed image of 30-100kb upload on server converting bitmap string ( base64.encodetostring() )

i thought work fine. when check uploaded image on server, size of image same original image size (original size before compressed) instead of compressed 30-100kb size image.

here code:

public string compressimage(string imageuri)   {     string filepath = getrealpathfromuri(imageuri);     bitmap scaledbitmap = null;      bitmapfactory.options options = new bitmapfactory.options();      options.injustdecodebounds = true;     bitmap bmp = bitmapfactory.decodefile(filepath, options);      int actualheight = options.outheight;     int actualwidth = options.outwidth;      float maxheight = 816.0f;     float maxwidth = 612.0f;     float imgratio = actualwidth / actualheight;     float maxratio = maxwidth / maxheight;      if (actualheight > maxheight || actualwidth > maxwidth) {         if (imgratio < maxratio) {               imgratio = maxheight / actualheight;                actualwidth = (int) (imgratio * actualwidth);               actualheight = (int) maxheight;             } else if (imgratio > maxratio) {             imgratio = maxwidth / actualwidth;             actualheight = (int) (imgratio * actualheight);             actualwidth = (int) maxwidth;         } else {             actualheight = (int) maxheight;             actualwidth = (int) maxwidth;          }     }      options.insamplesize = calculateinsamplesize(options, actualwidth, actualheight);      options.injustdecodebounds = false;      options.inpurgeable = true;     options.ininputshareable = true;     options.intempstorage = new byte[16 * 1024];      try {         bmp = bitmapfactory.decodefile(filepath, options);     } catch (outofmemoryerror exception) {         exception.printstacktrace();      }     try {         scaledbitmap = bitmap.createbitmap(actualwidth, actualheight,bitmap.config.argb_8888);     } catch (outofmemoryerror exception) {         exception.printstacktrace();     }      float ratiox = actualwidth / (float) options.outwidth;     float ratioy = actualheight / (float) options.outheight;     float middlex = actualwidth / 2.0f;     float middley = actualheight / 2.0f;      matrix scalematrix = new matrix();     scalematrix.setscale(ratiox, ratioy, middlex, middley);      canvas canvas = new canvas(scaledbitmap);     canvas.setmatrix(scalematrix);     canvas.drawbitmap(bmp, middlex - bmp.getwidth() / 2, middley - bmp.getheight() / 2, new paint(paint.filter_bitmap_flag));      exifinterface exif;     try {         exif = new exifinterface(filepath);          int orientation = exif.getattributeint(                 exifinterface.tag_orientation, 0);         log.d("exif", "exif: " + orientation);         matrix matrix = new matrix();         if (orientation == 6) {             matrix.postrotate(90);             log.d("exif", "exif: " + orientation);         } else if (orientation == 3) {             matrix.postrotate(180);             log.d("exif", "exif: " + orientation);         } else if (orientation == 8) {             matrix.postrotate(270);             log.d("exif", "exif: " + orientation);         }         scaledbitmap = bitmap.createbitmap(scaledbitmap, 0, 0,                 scaledbitmap.getwidth(), scaledbitmap.getheight(), matrix,                 true);     } catch (ioexception e) {         e.printstacktrace();     }      fileoutputstream out = null;     string filename = getfilename();     try {         out = new fileoutputstream(filename);         scaledbitmap.compress(bitmap.compressformat.jpeg, 80, out);      } catch (filenotfoundexception e) {         e.printstacktrace();     } return filename; }  public string getfilename() { file file = new file(environment.getexternalstoragedirectory().getpath(), "myfolder/images"); if (!file.exists()) {     file.mkdirs(); } string uristing = (file.getabsolutepath() + "/" +  system.currenttimemillis() + ".jpg");     return uristing;}  private string getrealpathfromuri(string contenturi) {     uri contenturi = uri.parse(contenturi);     cursor cursor = getcontentresolver().query(contenturi, null, null, null, null);     if (cursor == null) {         return contenturi.getpath();     } else {         cursor.movetofirst();         int index = cursor.getcolumnindex(mediastore.images.imagecolumns.data);         return cursor.getstring(index);     } }  public int calculateinsamplesize(bitmapfactory.options options, int reqwidth, int reqheight) { final int height = options.outheight; final int width = options.outwidth; int insamplesize = 1;  if (height > reqheight || width > reqwidth) {     final int heightratio = math.round((float) height/ (float) reqheight);     final int widthratio = math.round((float) width / (float) reqwidth);     insamplesize = heightratio < widthratio ? heightratio : widthratio;      }       final float totalpixels = width * height;       final float totalreqpixelscap = reqwidth * reqheight * 2;       while (totalpixels / (insamplesize * insamplesize) > totalreqpixelscap) {     insamplesize++; }     return insamplesize; 

}

am going wrong somewhere in above code ? there better method compress image. wondering how can uncompressed image(bitmap) getting uploaded instead of compressed one.

how whatsapp/instagram/facebook compresses image before uploading on server. there library it. thank you.

try this:

private string decodefile(string path,int desiredwidth, int desiredheight) {     string strmyimagepath = null;     bitmap scaledbitmap = null;      try {         // part 1: decode image         bitmap unscaledbitmap = scalingutilities.decodefile(path, desiredwidth, desiredheight, scalinglogic.fit);          if (!(unscaledbitmap.getwidth() <= desiredwidth && unscaledbitmap.getheight() <= desiredheight)) {             // part 2: scale image             scaledbitmap = scalingutilities.createscaledbitmap(unscaledbitmap, desiredwidth, desiredheight, scalinglogic.fit);         } else {             unscaledbitmap.recycle();             return path;         }          // store tmp file          string extr = environment.getexternalstoragedirectory().tostring();         file mfolder = new file(extr + "/tmmfolder");         if (!mfolder.exists()) {             mfolder.mkdir();         }          string s = "tmp.png";          file f = new file(mfolder.getabsolutepath(), s);          strmyimagepath = f.getabsolutepath();         fileoutputstream fos = null;         try {             fos = new fileoutputstream(f);             scaledbitmap.compress(bitmap.compressformat.jpeg, 75, fos);             fos.flush();             fos.close();         } catch (filenotfoundexception e) {              e.printstacktrace();         } catch (exception e) {              e.printstacktrace();         }          scaledbitmap.recycle();     } catch (throwable e) {     }      if (strmyimagepath == null) {         return path;     }     return strmyimagepath;  } 

scalingutilities.java

import android.content.res.resources; import android.graphics.bitmap; import android.graphics.bitmap.config; import android.graphics.bitmapfactory; import android.graphics.bitmapfactory.options; import android.graphics.canvas; import android.graphics.paint; import android.graphics.rect;  /**  * class containing static utility methods bitmap decoding , scaling  *  * @author   */ public class scalingutilities {      /**      * utility function decoding image resource. decoded bitmap      * optimized further scaling requested destination dimensions      * , scaling logic.      *      * @param res resources object containing image data      * @param resid resource id of image data      * @param dstwidth width of destination area      * @param dstheight height of destination area      * @param scalinglogic logic use avoid image stretching      * @return decoded bitmap      */     public static bitmap decoderesource(resources res, int resid, int dstwidth, int dstheight,             scalinglogic scalinglogic) {         options options = new options();         options.injustdecodebounds = true;         bitmapfactory.decoderesource(res, resid, options);         options.injustdecodebounds = false;         options.insamplesize = calculatesamplesize(options.outwidth, options.outheight, dstwidth,                 dstheight, scalinglogic);         bitmap unscaledbitmap = bitmapfactory.decoderesource(res, resid, options);          return unscaledbitmap;     }     public static bitmap decodefile(string path, int dstwidth, int dstheight,             scalinglogic scalinglogic) {         options options = new options();         options.injustdecodebounds = true;         bitmapfactory.decodefile(path, options);         options.injustdecodebounds = false;         options.insamplesize = calculatesamplesize(options.outwidth, options.outheight, dstwidth,                 dstheight, scalinglogic);         bitmap unscaledbitmap = bitmapfactory.decodefile(path, options);          return unscaledbitmap;     }      /**      * utility function creating scaled version of existing bitmap      *      * @param unscaledbitmap bitmap scale      * @param dstwidth wanted width of destination bitmap      * @param dstheight wanted height of destination bitmap      * @param scalinglogic logic use avoid image stretching      * @return new scaled bitmap object      */     public static bitmap createscaledbitmap(bitmap unscaledbitmap, int dstwidth, int dstheight,             scalinglogic scalinglogic) {         rect srcrect = calculatesrcrect(unscaledbitmap.getwidth(), unscaledbitmap.getheight(),                 dstwidth, dstheight, scalinglogic);         rect dstrect = calculatedstrect(unscaledbitmap.getwidth(), unscaledbitmap.getheight(),                 dstwidth, dstheight, scalinglogic);         bitmap scaledbitmap = bitmap.createbitmap(dstrect.width(), dstrect.height(),                 config.argb_8888);         canvas canvas = new canvas(scaledbitmap);         canvas.drawbitmap(unscaledbitmap, srcrect, dstrect, new paint(paint.filter_bitmap_flag));          return scaledbitmap;     }      /**      * scalinglogic defines how scaling should carried out if source ,      * destination image has different aspect ratio.      *      * crop: scales image minimum amount while making sure @ least      * 1 of 2 dimensions fit inside requested destination area.      * parts of source image cropped realize this.      *      * fit: scales image minimum amount while making sure both      * dimensions fit inside requested destination area. resulting      * destination dimensions might adjusted smaller size      * requested.      */     public static enum scalinglogic {         crop, fit     }      /**      * calculate optimal down-sampling factor given dimensions of source      * image, dimensions of destination area , scaling logic.      *      * @param srcwidth width of source image      * @param srcheight height of source image      * @param dstwidth width of destination area      * @param dstheight height of destination area      * @param scalinglogic logic use avoid image stretching      * @return optimal down scaling sample size decoding      */     public static int calculatesamplesize(int srcwidth, int srcheight, int dstwidth, int dstheight,             scalinglogic scalinglogic) {         if (scalinglogic == scalinglogic.fit) {             final float srcaspect = (float)srcwidth / (float)srcheight;             final float dstaspect = (float)dstwidth / (float)dstheight;              if (srcaspect > dstaspect) {                 return srcwidth / dstwidth;             } else {                 return srcheight / dstheight;             }         } else {             final float srcaspect = (float)srcwidth / (float)srcheight;             final float dstaspect = (float)dstwidth / (float)dstheight;              if (srcaspect > dstaspect) {                 return srcheight / dstheight;             } else {                 return srcwidth / dstwidth;             }         }     }      /**      * calculates source rectangle scaling bitmap      *      * @param srcwidth width of source image      * @param srcheight height of source image      * @param dstwidth width of destination area      * @param dstheight height of destination area      * @param scalinglogic logic use avoid image stretching      * @return optimal source rectangle      */     public static rect calculatesrcrect(int srcwidth, int srcheight, int dstwidth, int dstheight,             scalinglogic scalinglogic) {         if (scalinglogic == scalinglogic.crop) {             final float srcaspect = (float)srcwidth / (float)srcheight;             final float dstaspect = (float)dstwidth / (float)dstheight;              if (srcaspect > dstaspect) {                 final int srcrectwidth = (int)(srcheight * dstaspect);                 final int srcrectleft = (srcwidth - srcrectwidth) / 2;                 return new rect(srcrectleft, 0, srcrectleft + srcrectwidth, srcheight);             } else {                 final int srcrectheight = (int)(srcwidth / dstaspect);                 final int scrrecttop = (int)(srcheight - srcrectheight) / 2;                 return new rect(0, scrrecttop, srcwidth, scrrecttop + srcrectheight);             }         } else {             return new rect(0, 0, srcwidth, srcheight);         }     }      /**      * calculates destination rectangle scaling bitmap      *      * @param srcwidth width of source image      * @param srcheight height of source image      * @param dstwidth width of destination area      * @param dstheight height of destination area      * @param scalinglogic logic use avoid image stretching      * @return optimal destination rectangle      */     public static rect calculatedstrect(int srcwidth, int srcheight, int dstwidth, int dstheight,             scalinglogic scalinglogic) {         if (scalinglogic == scalinglogic.fit) {             final float srcaspect = (float)srcwidth / (float)srcheight;             final float dstaspect = (float)dstwidth / (float)dstheight;              if (srcaspect > dstaspect) {                 return new rect(0, 0, dstwidth, (int)(dstwidth / srcaspect));             } else {                 return new rect(0, 0, (int)(dstheight * srcaspect), dstheight);             }         } else {             return new rect(0, 0, dstwidth, dstheight);         }     }  }