How to compress jpg/bmp files which I can store in the memory then when needed decompress those images and show to users without losing too much of image quality? How to do the compress and decompress, any guidance/ link would be helpful.
Thank you
create image thumbnails
'byte[] imageData = null;
try
{
final int THUMBNAIL_SIZE = 64;
FileInputStream fis = new FileInputStream(fileName);
Bitmap imageBitmap = BitmapFactory.decodeStream(fis);
imageBitmap = Bitmap.createScaledBitmap(imageBitmap, THUMBNAIL_SIZE, THUMBNAIL_SIZE, false);
ByteArrayOutputStream baos = new ByteArrayOutputStream();
imageBitmap.compress(Bitmap.CompressFormat.JPEG, 100, baos);
imageData = baos.toByteArray();
}
catch(Exception ex) {
}`
if u need for thumbNail then use
ThumbNailUtils.extractThumbnail(Bitmap source,int width,int height)
it show thumbnail from bitmap and when u want to show original bitmap then show bitmap
.
use wisely bitmap object cause it take more memory at runtime.
Related
I had a problem where some of my images are loaded inside imageview rotated. I solved the problem by loading an image using Glide.
The image is loaded inside 100 x 100 imageview. Can I retrieve the image which is stored inside that imageview as 100 x 100 and upload it to the server instead of sending the original image?
Yes you can
public byte[] getImageFromImageView(ImageView imageView,String filePath) {
Drawable imageDrawable = imageView.getDrawable();
Bitmap imageBitmap = ((BitmapDrawable)imageDrawable).getBitmap();
ByteArrayOutputStream stream = new ByteArrayOutputStream();
imageBitmap.compress(Bitmap.CompressFormat.PNG, 100, stream);
byte[] byteArray = stream.toByteArray();
return byteArray;
}
Then upload file to server or you can create RequestBodyand send it to server if you using Retrofit.
I have an app that takes a picture, assigns it to an imageview and then uploads it to a parse server.
The problem is that I need the images to be 200 x 200 px before upload.
Is there a way to do this programatically?
this is my function so far:
public void Myfunction (){
//image
ImageView imageView = (ImageView) findViewById(R.id.imageView);
Bitmap bitmap = ((BitmapDrawable) imageView.getDrawable()).getBitmap();
ByteArrayOutputStream baos = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.JPEG, 40, baos);
byte[] imageInByte = baos.toByteArray();
ParseFile file = new ParseFile("myimage.jpg",imageInByte);
Could anyone help me please?
To scale bitmap down before compress, add
bitmap = Bitmap.createScaledBitmap(bitmap, 200, 200, false));
If your bitmap is not square, you probably want to crop it before scaling
I have a list of mp4 files that i need to extract a thumbnail for each one.
Thumbnail criteria:
The thumbnail must be in Base64 format
The thumbnail has a specific size which will be provided as a method parameter
It must be extracted from the frame in the middle of the file (e.g. if the video duration is 10s then the thumbnail must be from the frame in 5th second.
1 and 2 are currently achieved but I'm not sure how to do 3.
This is my code:
public static String getVideoDrawable(String path, int height, int width) throws OutOfMemoryError{
try {
Bitmap bitmap = ThumbnailUtils.createVideoThumbnail(path, android.provider.MediaStore.Images.Thumbnails.MINI_KIND);
bitmap = Bitmap.createScaledBitmap(bitmap, height, width, false);
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.JPEG, 100, byteArrayOutputStream);
byte[] byteArray = byteArrayOutputStream .toByteArray();
return Base64.encodeToString(byteArray, Base64.DEFAULT);
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
You need to use the MediaMetadataRetriever for that.
MediaMetadataRetriever metadataRetriever = new MediaMetadataRetriever();
try {
metadataRetriever.setDataSource(path);
String duration=metadataRetriever.extractMetadata(MediaMetadataRetriever.METADATA_KEY_DURATION);
long time=Long.valueOf(duration)/2;
Bitmap bitmap = metadataRetriever.getFrameAtTime(time,MediaMetadataRetriever.OPTION_NEXT_SYNC);
//now convert to base64
} catch (Exception ex) {
}
http://developer.android.com/intl/es/reference/android/media/MediaMetadataRetriever.html#getFrameAtTime%28long,%20int%29
I need to obtain the pixel data from a BufferedImage so I can recreate the image from the data. I looked into Raster, but that did not seem to contain the information I need. How can I obtain data from a BufferedImage so I can recreate the image without needing the original file?
You should check out the answers to this question
Java - get pixel array from image
One way to do it is to use
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ImageIO.write(originalImage, "jpg", baos);
baos.flush();
byte[] imageBytes = baos.toByteArray();
baos.close();
Now when you want to create a new BufferedImage from the data you use
ByteArrayInputStream bais = new ByteArrayInputStream(imageBytes);
BufferedImage newImage = null;
try {
newImage = ImageIO.read(bais);
} catch (IOException e) {
// handle exception
}
I am creating an application over Android where I need to manipulate my JPG files. I am not getting much of header information for JPG format so for that I am converting it to Bitmap, manipulated the pixel values in bitmap and then again convert it back to JPG.
Here what problem I am facing is- after manipulating only some pixels of bitmap and
converting it back to JPG, I do not get the same set of pixels I got earlier (for those pixels which I did not manipulate). I am getting the same image as the original in the new image. But when I check new image pixels values for decoding, the untouched pixels are different...
File imagefile = new File(filepath);
FileInputStream fis = new FileInputStream(imagefile);
Bitmap bi = BitmapFactory.decodeStream(fis);
int intArray[];
bi=bi.copy(Bitmap.Config.ARGB_8888,true);
intArray = new int[bi.getWidth()*bi.getHeight()];
bi.getPixels(intArray, 0, bi.getWidth(), 0, 0, bi.getWidth(), bi.getHeight());
int newArray[] = encodeImage(msgbytes,intArray,mbytes); // method where i am manipulating my pixel values
// converting the bitmap data back to JPG file
bi = Bitmap.createBitmap(newArray, bi.getWidth(), bi.getHeight(), Bitmap.Config.ARGB_8888);
ByteArrayOutputStream baos = new ByteArrayOutputStream();
bi.compress(Bitmap.CompressFormat.JPEG, 100, baos);
byte[] data = baos.toByteArray();
Bitmap bitmapimage = BitmapFactory.decodeByteArray(data, 0, data.length);
String filepath = "/sdcard/image/new2.jpg";
File imagefile = new File(filepath);
FileOutputStream fos = new FileOutputStream(imagefile);
bitmapimage.compress(CompressFormat.JPEG, 100, fos);
Help me if I am wrong somewhere or whether I should use some other method to manipulate JPG pixel values...
JPEG is an image format that is usually based on lossy compression. That means that some information that is not important for the human eye is thrown away to further shrink the file size. Try to save your image as a PNG (a lossless format).
Be careful with using
Bitmap bi = BitmapFactory.decodeStream(fis);
bi = bi.copy(Bitmap.Config.ARGB_8888, true);
At the point where you have the first bi you may have already lost a lot of information, instead try using BitmapFactory.Options to force 8888 (which is the default too):
BitmapFactory.Options options = new BitmapFactory.Options();
options.inPreferredConfig = Bitmap.Config.ARGB_8888;
options.inDither = false;
Bitmap bi = BitmapFactory.decodeStream(fis, options);
If you stay with copy you should still recycle() the one that you throw away.