image-compression

I'm using this compression class from the following site: http://voidcanvas.com/whatsapp-like-image-compression-in-android/ Here is my compression class with very little modifications from the original class: import android.content.Context; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.graphics.Canvas; import android.graphics.Matrix; import android.graphics.Paint; import android.media.ExifInterface; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import timber.log.Timber; //http://voidcanvas.com/whatsapp

Having an ecommerce website, We have thousands of product images. On checking pagespeed on google it shows me something like this: I was wondering, if there is any built in feature in Java or any third party library is available with which we can losslessly compress all the images that we host. Hence we can save few KBs of our customers. On searching through internet I found few like punnypng and kraken which are paid, hence we do not have heavy image uploaded every month, subscribing to them is not worth. I would prefer any built in feature in Java or any open source third party library. I

Background I need to rotate images taken by the camera so that they will always have a normal orientation. for this, I use the next code (used this post to get the image orientation) //<= get the angle of the image , and decode the image from the file final Matrix matrix = new Matrix(); //<= prepare the matrix based on the EXIF data (based on https://gist.github.com/9re/1990019 ) final Bitmap rotatedBitmap = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(),matrix,false); bitmap.recycle(); fileOutputStream = new FileOutputStream(tempFilePath); rotatedBitmap.compress

I want to convert my photos from jpg, gif and png to WebP format! When I'm trying to use CMD for using cwebp command, I got this error message : 'cwebp' is not recognized as an internal or external command, operable program or batch file. What should do I do ? I've downloaded all the files needed such as libwebp-0.4.0-windows-x86.zip and WebpCodecSetup.exe (from this url : " https://code.google.com/p/webp/downloads/list "). even I've installed Visual Studio to use its command prompt, but didn't work !!! Is there anyone can help me ?? One more questation: Is anyone know any tool to reduce image

Closed. This question is off-topic. It is not currently accepting answers. Learn more . Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed 2 years ago . Running Google Page Speed on a public site , I saw some suggestions by the tool like the following : Losslessly compressing http://g-ecx.images-amazon.com/images/G/01/electronics/detail-page/Acer-120x120._V137848950_.gi could save 4.8KiB (26% reduction) and they also provide a link to the optimized content.But they do it on a per image basis. I saw some significant reduction on file sizes after

I went through how DCT (discrete cosine transform) is used in image and video compression standards. But why DCT only is preferred over other transforms like dft or dst? Because cos(0) is 1, the first (0th) coefficient of DCT-II is the mean of the values being transformed. This makes the first coefficient of each 8x8 block represent the average tone of its constituent pixels, which is obviously a good start. Subsequent coefficients add increasing levels of detail, starting with sweeping gradients and continuing into increasingly fiddly patterns, and it just so happens that the first few