Develop Reference

How to download images with specific size from firebase storage

I am using firebase storage in my android app to store images uploaded by users. all images uploaded are square in shape.
I discovered that downloading this images consumes a lot of user bandwidth and i would like to reduce this consumption by reducing the size of image downloaded into a square imageview
I am using Glide to download this images and i have tried to download images of custom size but the image is not appearing on the imageview.
interface
public interface MyDataModel {
public String buildUrl(int width, int height);
}
my class which extends BaseGlideUrlLoader
public class MyUrlLoader extends BaseGlideUrlLoader<MyDataModel> {
public MyUrlLoader(Context context) {
super(context);
}
#Override
protected String getUrl(MyDataModel model, int width, int height) {
// Construct the url for the correct size here.
return model.buildUrl(width, height);
}
}
class which implements MyDataModel interface
public class CustomImageSize implements MyDataModel {
private String uri;
public CustomImageSize(String uri){
this.uri = uri;
}
#Override
public String buildUrl(int width, int height) {
return uri + "?w=" + width + "&h=" + height;
}
}
Finally
CustomImageSize size = new CustomImageSize(uri);
Glide.with(context)
.using(new MyUrlLoader(context))
.load(size)
.centerCrop()
.priority(Priority.HIGH)
.into(imageView);
RESULTS OF SOLUTION ABOVE
Image is not appearing in my square imageview
SOLUTION 2: use firebase image loader
// Reference to an image file in Firebase Storage
StorageReference storageReference = ...;
ImageView imageView = ...;
// Load the image using Glide
Glide.with(this /* context */)
.using(new FirebaseImageLoader())
.load(storageReference)
.into(imageView);
RESULT OF SOLUTION 2 ABOVE
working! image is appearing BUT it's like entire image is been downloaded which consume a lot of bandwidth. I just want a custom size image e.g 200px by 200px to be downloaded.
How can I do or change in my solution 1 above to download images of custom size from firebase storage?
EDIT
I have tried to access one of my images https://firebasestorage.googleapis.com/....m.png from the browser and it was loaded successfully to the webpage. but when i try to put to size specific parameters to my image url link https://firebasestorage.googleapis.com/....m.png?w=100&h=100 an error appeared on the webpage
{
"error": {
"code": 403,
"message": "Permission denied. Could not perform this operation"
}
}

I was finally able to download images from firebase storage using MyUrlLoader class
You see, firebase storage urls look like this
firebasestorage.googleapis.com/XXXX.appspot.com/Folder%2Image.png?&alt=media&token=XXX
As you can see above, the link already have this special question mark character ? which stands for the start of querying string so when i use CustomImageSize class, another ? was being added so the link was ending up with two ? which made downloading to fail
firebasestorage.googleapis.com/XXXX.appspot.com/Folder%2Image.png?&alt=media&token=XXX?w=200&h=200
Solution was to remove the ? in my CustomImageSize class. so it ended up like this
public class CustomImageSize implements MyDataModel {
private String uri;
public CustomImageSize(String uri){
this.uri = uri;
}
#Override
public String buildUrl(int width, int height) {
return uri + "w=" + width + "&h=" + height;
}
}
Although it downloaded, am not sure whether entire image was being downloaded or just the custom size one. This is because, i tried to access the image in my browser after correcting the error that was making viewing to fail, but still i was receiving an entire image. not a resized image (w=200&h=200)

Try downloading your image using the following commands:-
StorageReference islandRef = storageRef.child("yourImage.jpg");
// defines the specific size of your image
final long ONE_MEGABYTE = 1024 * 1024;
islandRef.getBytes(ONE_MEGABYTE).addOnSuccessListener(new OnSuccessListener<byte[]>() {
#Override
public void onSuccess(byte[] bytes) {
// Data for "yourImage.jpg" is returns, use this as needed
}
}).addOnFailureListener(new OnFailureListener() {
#Override
public void onFailure(#NonNull Exception exception) {
// Handle any errors
}
});

Bitmap download for numerous images causing issue

I am learning Android dev. and am developping a Hearthstone app using a Hearthstone API for fun.
My users can search for specific cards and now I wish to implement a Card Displayer that displays cards by their type, and lets the user swipe right or left to display the next one in my JSONArray. My API request gives me one and each JSONObject has an img attribute with the cards image URL.
Therefore, when the user swipes I am doing the following:
// Swipe right -> number - 1 (Previous page)
// Swipe left -> number + 1 (Next page)
public void displayCardNumber(int number) {
APIRequests apiRequests = new APIRequests();
try {
// Gets the JSONObject at 'number' and retrieves its img URL.
JSONObject card = (JSONObject) cardsArray.get(number);
String currentImageURL = (String) card.get("img");
// Here is where my problem is.
Bitmap bitmap = apiRequests.getImageBitmap(currentImageURL);
if (bitmap != null) {
setNewImage(bitmap);
}
} catch (JSONException e) {
e.printStackTrace();
}
}
But apiRequest.getImageBitmap(URL) is where I have a problem.
I must download the image in order to display it, but not only does the following block of code not work when I download more than one image, I must also find an efficient way of displaying my cards (that requires background download perhaps?).
// Returns the image's bitmap using the URL
protected Bitmap getImageBitmap(String currentImageURL) {
try {
Bitmap bitmap = BitmapFactory.decodeStream((InputStream)new URL(currentImageURL).getContent());
return bitmap;
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
Why can't I download more than 1 image? Is my way of getting my Bitmap false?
Thank you.

Use Glide https://github.com/bumptech/glide .This is faster.
Bitmap theBitmap = Glide.
with(this).
load(imgUrl). //image url as string
asBitmap().
into(100, 100). // Width and height
get();
You can also use it with another way like this:
Glide.with(context).load(url) // image url
.thumbnail(0.5f)
.crossFade()
.diskCacheStrategy(DiskCacheStrategy.ALL)
.placeholder(imgId) // If no image found the imgId is the default image id for the imageView
.into(imageView); // imageView to show the image

I have found a solution,
In order to load my image and display it I now use a library called Android Universal Image Loader that lets me do the following:
// Load image, decode it to Bitmap and display Bitmap in ImageView
ImageLoader imageLoader = ImageLoader.getInstance();
ImageView i = (ImageView)view.findViewById(R.id.cardDisplay);
imageLoader.displayImage(currentImageURL, i);
I retrieve the correct URL in my AsyncTask's doInBackground and display it with the library's method.

Picasso - how to get the real image size?

I load an image from URLusing Picasso library. I want to get the real image size, but I can only get the image size in memory:
Picasso.with(this)
.load(imageUrl)
.error(R.drawable.no_image)
.into(photoView, new Callback() {
#Override
public void onSuccess() {
Bitmap bitmap = ((BitmapDrawable)photoView.getDrawable()).getBitmap();
textImageDetail.setText(bitmap.getByteCount());// image size on memory, not actual size of the file
}
#Override
public void onError() { }
});
How to get the size of the loaded image? I think it is stored somewhere in a cache, but I do not know how to access the image file.
Update
Sorry for my bad English, maybe I asked the wrong question. I need to get the image size (128 kb, 2 MB, etc.). NOT the image resolution (800x600, etc.)

You could first get the actual Bitmap image that is getting loaded, and then find the dimensions of that. This has to be run in an asynchronous method like AsyncTask because downloading the image is synchronous. Here is an example:
Bitmap downloadedImage = Picasso.with(this).load(imageUrl).get();
int width = downloadedImage.getWidth();
int height = downloadedImage.getHeight();
If you want to get the actual image size in bytes of the Bitmap, just use
// In bytes
int bitmapSize = downloadedImage.getByteCount();
// In kilobytes
double kbBitmapSize = downloadedImage.getByteCount() / 1000;
Replace the imageUrl with whatever URL you want to use. Hope it helps!

I know this question is old, but I stepped here for an answer and found none.
I found a solution that worked with me using OkHttpClient.
You can fetch the header information only, using OkHttpClient and get the content length without downloading the image.
OkHttpClient httpClient = new OkHttpClient();
Request request = new Request.Builder().url(imageURL).head().build();
Response response = null;
try {
response = httpClient.newCall(request).execute();
String contentLength = response.header("content-length");
int size = Integer.parseInt(contentLength);
} catch (IOException e ) {
if (response!=null) {
response.close();
}
}
Notes:
the above code performs a network call, it should be executed on a background thread.
size is returned in Bytes, you can divide by 1000 if you want it in KB.
this may not work with large files.
Beware, casting to integer could bypass the integer's max value.

Add pre-cached images in apk file for use with Picasso or similar library

I am using Picasso for retrieving and showing images in my Android app. To avoid downloading all images over the network I am trying to add some images with the apk file, as sort of a pre-cached set of images. These images are stored in the assets folder and then copied to the Picasso cache folder on installation. This works as expected, but Picasso still download all images through the network and caches them as .0 and .1 files like this:
root#generic_x86:/data/data/com.my.app/files/images_cache #
ls
10.JPG
100.JPG
101.JPG
102.JPG
11.JPG
1f94664dec9a8c205b7dc50f8a6f3b79.0
1f94664dec9a8c205b7dc50f8a6f3b79.1
2.JPG
4621206beccad87a0fc01df2d080c644.0
4621206beccad87a0fc01df2d080c644.1
The *.JPG images are the ones I copied and the others are the Picasso cached images. Is there a way to make Picasso cache these images properly on installation?
If not, are there any other similar libraries that supports this kind of pre-caching?
Update: trying to cache from Assets folder
I tried making a small snippet that is run at first run of the app. The idea is to iterate the files in the given assets folder and fetch those images with Picasso. However, the below does not cache anything, although I end up in the onSuccess() method of the callback. The asset file names are correct. This is also verified by using the wrong folder name, which puts me in the onError() method of the callback.
I also tried loading it into a temporary ImageView, but it did do any difference.
public static boolean cacheImagesFromAssetsFolder(Context context)
{
boolean ok = false;
try
{
String[] images = context.getAssets().list("my_images");
for (String image : images)
{
Picasso.with(context).load("file:///android_asset/my_images/" + image).fetch(new Callback()
{
#Override
public void onSuccess()
{
// This is where I end up. Success, but nothing happens.
}
#Override
public void onError()
{
}
});
}
ok = true;
}
catch (Exception e)
{
e.printStackTrace();
}
return ok;
}

You could use File URI to request the Picasso to pick the image from your asset location instead of n/w.
Picasso.with(activity) //
.load(Uri.fromFile(file)) // Location of the image from asset folder
Update: How to use your own cache
import com.squareup.picasso.LruCache;
import com.squareup.picasso.Util;
LruCache imageCache = new LruCache(context);
Request request = Request.Builder(Uri.fromFile(asset_file), 0, null).build();
String cacheKey = Util.createKey(request, new StringBuilder());
imageCache.set(cacheKey, bitmap_object_of_asset_image);
Picasso.Builder(context)
.memoryCache(imageCache)
.build().load(asset_url).fetch(callback);

AQuery: How to download images in non-sequential manner without any reference to imageView in the aQuery call

Question 1: Is it possible to download image file without giving the reference to ImageView?
Question 2: Can i download each file in a separage instance of aQuery or do i have to download the file sequentially? e.g, waiting for the callback of current file download and then trigger the next file download call? Below is my code
// Ad is my custom model class
// adList is my list of Ads having URL's to the ads hosted somewhere
// imageView is an invisible imageView as downloading does not start if i don't give any reference to any imageView resource
for (String adUrl : adList) {
if (adUrl.length() > 0) {
AQuery aQuery = new AQuery(DownloadAdActivity.this);
BitmapAjaxCallback callback = new BitmapAjaxCallback();
callBack.url(adUrl);
callBack.fallback(R.id.placeHolderResource);
callBack.fileCache(true);
callBack.memCache(true);
aQuery.id(imageView).image(callBack);
}
}
I need to download 20/30 images when the app starts first time, so far i am doing it by giving a hidden imageView reference and trigging the aQuery sequentially after each image has downloaded. I tried to generate 20/30 request in a loop but only the last aQuery trigger call works which cancels the previous image download call.
Please guide me:
1- How to cache images without giving any reference to the imageView
2- How to download images in parallel manner, not in sequential manner through AQuery.

1) You can use ajax call without ImageView reference to download image.
androidQuery.ajax("url", Bitmap.class, 0, new AjaxCallback<Bitmap>() {
#Override
public void callback(String url, Bitmap bitmap, AjaxStatus status) {
super.callback(url, bitmap, status);
}
});
2) By default you can download 4 images concurrently. But you can change as per your requirement like this
AjaxCallback.setNetworkLimit(8);

You can use Picasso
It will make all the downloads and also the caching for the images.
Anyway if the images are quite small you should prepare a "zip" file and dl all of them with an AsyncTask / Thread and unzip them. Opening and closing the connections to the server are "very expensive" operations in time consuming.

Here is method to obtain bitmap from url using AQuery
static Bitmap myBitmap = null;
public static Bitmap getBitmapFromURL(String src) {
try {
Log.i(TAG, "Image Url is : " + src);
AQuery androidQuery = new AQuery(ChatApplication.getInstance());
androidQuery.ajax(src, Bitmap.class, 0, new AjaxCallback<Bitmap>() {
#Override
public void callback(String url, Bitmap bitmap, AjaxStatus status) {
super.callback(url, bitmap, status);
if (bitmap != null)
myBitmap = bitmap;
}
});
} catch (Exception e) {
Log.i(TAG, "Error due to " + e);
}
return myBitmap;
}

AQuery aq = new AQuery(context);
aq.ajax(url_of_image, Bitmap.class, new AjaxCallback<Bitmap>() {
#Override
public void callback(String url, Bitmap object, AjaxStatus status) {
}
});
Im sorry for replying late,But this is best library I have ever came across.
Yes,You can download. Bitmap object will give you the image.
You can create multiple instances of Aquery if you want to download or pass the each URL after one download finishes,you can use any loop for that.