Develop Reference

Reduce Bitmap size

So, I'm updating an old e-book reader. The problem I'm facing is the size of the bitmaps (the pages). The way it works is: the app downloads a file, extract it, decode it with our DRM then I can access all pages. The thing is, each page its a 35mb bitmap.
I need to reduce this by a lot. I can't convert the file to any other format.
I tried this:
byte[] rawBytes = intToByteArray(b.getByteCount());
BitmapFactory.Options options = new BitmapFactory.Options();
options.inSampleSize = 4;
Bitmap bit = BitmapFactory.decodeByteArray(rawBytes, 0,rawBytes.length, options);
But the Bitmap keeps returning null, and for what I gathered its when the Bitmap facorty can't decode the bitmap.
So, there is any other way to reduce the impact of this big bitmaps ?

Android bitmap size reduction not reducing memory

I'm new to android and am working on my first real app so i apologize if this question has been answered, or isn't detailed enough. I'm having the common OutOfMemoryError when loading bitmaps to my android app. I've searched around on stackoverflow and went through the google tutorial that describes how to use InSampleSize to reduce the memory for each bitmap.
When testing out the app to see how much memory I was saving by down scaling my bitmaps I noticed that the heap size was still growing at the same rate. I.E. When I use an InSampleSize = 8 vs not scaling the bitmap at all (or InSampleSize = 1) the heap grows the same for each.
I have tried printing the byteCount with:
myImage.getByteCount()
for both of the scaling SampleSizes listed above and they both have identical ByteCounts. Is this the expected behavior? Shouldn't the byte count be reduced since I'm downscaling images?
I was expecting to see the memory used to the bitmap reduced by a factor of 8 or so. Am I missing something, or is my understanding of image scaling incorrect? Thanks.
edit: After doing some testing I discovered that if I used createScaledBitmap the memory was reduced but it required me first inflating the original Bitmap then scaling. I'm assuming this is non-ideal since it requires that. I thought the first method would do this for me but according to my heap dumps it isn't.
Initial Code and heap dump:
private static Bitmap decodeSampledBitmap(Resources res, int resId, int width, int height
{
// First decode with inJustDecodeBounds=true to check dimensions
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
options.inPreferredConfig = Config.ARGB_8888;
BitmapFactory.decodeResource(res, resId, options);
// Calculate inSampleSize
options.inSampleSize = calculateInSampleSize(options, width, height);
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
return BitmapFactory.decodeResource(res, resId, options);
}
Updated code (same as above with the only difference being) and heap dump:
private static Bitmap decodeSampledBitmap(Resource res, int ResId, int width, int height)
{
....
Bitmap bitmap = BitmapFactory.decodeResource(res, resId, options);
return Bitmap.createScaledBitmap(bitmap, options.outWidth/options.inSampleSize, options.outHeight/options.inSampleSize, false);
}
It won't let me post images due to my reputation but according to heap dump it is using 79.155MB. Using the second technique the heap dump is using 26.912 MB.

Are you scaling the Bitmap after decoding it using InSampleSize?

Large bitmaps not loading efficiently from sdcard in Android

By following this link, I have written the following code to show a large image bitmap from sdcard.
try {
InputStream lStreamToImage = context.getContentResolver().openInputStream(Uri.parse(imagePath));
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeStream(lStreamToImage, null, options);
options.inSampleSize = 8; //Decrease the size of decoded image
options.inPreferredConfig = Bitmap.Config.ARGB_4444;
options.inJustDecodeBounds = false;
bitmap = BitmapFactory.decodeStream(lStreamToImage, null, options);
} catch(Exception e){}
image.setImageBitmap(bitmap);
But it is not returning the bitmap(I mean it returns null). In logcat it is showing the below message repeatedly
08-02 17:21:04.389: D/skia(19359): --- SkImageDecoder::Factory returned null
If I will comment the options.inJustDecodeBounds line and rerun it, it works fine but slowly. The developer guide link I provided above says to use inJustDecodeBounds to load bitmaps efficiently.
Please tell me where I am doing wrong.

inJustDecodeBounds does not load bitmaps. That's the point of it. It loads the dimensions of the bitmap without loading the actual bitmap so you can do any pre-processing or checking on the bitmap before you actually load it. This is helpful is you, say, were having memory issues and you needed to check if loading a bitmap would crash you program.
The reason your bitmap might be loading slowly is because it's probably very large and SD cards are very slow.
EDIT:
From the documentation:
If set to true, the decoder will return null (no bitmap), but the out... fields will still be set, allowing the caller to query the bitmap without having to allocate the memory for its pixels.
Edit 2:
Looking at your code with the example provided by Google, it looks like you are doing relatively the same thing. The reason it's returning null is possibly your InputStream has been modified in the first decoding and thus not starting at the beginning of the bitmap's memory address (they use a resource ID rather than InputStream.
From the code you supplied here, here's what I've figured. You are ALWAYS setting a sample size to 8 regardless of what the first decoding gives you. The reason Google decodes the first time is to figure out what the actual size of the bitmap is versus what they want. They determine that the bitmap is ZxZ dimensions and they want YxY dimensions, so they calculate the samplesize that they should use from the second decoding. You are not doing this. You are simply retrieving the dimensions of the bitmap and not using them. THEN, you set the sample size to a hard-coded 8, swapping it to a hard-coded ARGB_4444 bitmap, then decoding the full bitmap in to memory. In other words, these three lines are not being used:
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeStream(lStreamToImage, null, options);
Setting inJustDecodeBounds merely gives you the bitmap's dimensions without putting the bitmap in to memory. It doesn't make it more efficient. It's meant to allow you to load bitmaps in a smaller memory space if they are too big because you can pre-decide what size it should be without decoding the whole thing).
The reason decoding the bitmap is slow might merely be a CPU thing. Depending on the size of your bitmap, you're loading the bitmap from an InputStream from the SDcard which is a slow operation in itself.

BitmapFactory.Options.inSampleSize not being honored?

I have a photo on disk with dimensions 2560 x 1920. This is often too large to load into memory, so I'm trying to use BitmapFactory.Options.inSampleSize to conserve memory. From the docs:
inSampleSize: If set to a value > 1, requests the decoder to subsample the original image, returning a smaller image to save memory.
This is how I use it:
BitmapFactory.Options optsDownSample = new BitmapFactory.Options();
optsDownSample.inSampleSize = 3;
Bitmap bmp = BitmapFactory.decodeFile(path, optsDownSample);
but the app still sometimes crashes on the last line there, and from logcat I can see it's trying to allocate ~5mb, and I suspect this is because the downsampling is not really being honored.
Anyone else know what could be going on here, am I using inSampleSize incorrectly?
Thanks

I'm also struggling understanding how to use the BitmapFactory.Options, based on all the documentation I've read I believe you are just missing the optsDownSample.inJustDecodeBounds = false; as indicated on the Android Developers site.
Best of lucks!

android - out of memory exception when creating bitmap

This question already has answers here:
Strange OutOfMemory issue while loading an image to a Bitmap object
(44 answers)
Closed yesterday.
I am getting the following error after creating bitmap second time around:
04-17 18:28:09.310: ERROR/AndroidRuntime(3458): java.lang.OutOfMemoryError: bitmap size exceeds VM budget
this._profileBitmap = Bitmap.createBitmap(_profileBitmap, xCoor, yCoor, width, height);
From log:
04-17 18:27:57.500: INFO/CameraCropView(3458): Original Photo Size: W 1536 x H 2048
04-17 18:28:06.170: INFO/CameraCropView(3458): xCoor: 291
04-17 18:28:06.170: INFO/CameraCropView(3458): yCoor: 430
04-17 18:28:06.170: INFO/CameraCropView(3458): Width: 952
04-17 18:28:06.170: INFO/CameraCropView(3458): Height: 952
Since the image is huge I get the error. But the interesting thing is the error does not happen the first time, only when I take the picture the second time, which makes me believe this profileBitmap is NOT destroyed. How do I clean this up?

I had the same problem and fix it this way:
My app was ~18MB size, and when I see how much memory left free I was shocked - 654KB (on 1GB RAM!). So I just deleted almost all images from project and downloaded them from the internet on first start, and use pics from SD card when needed.
To check total/free memory for your app use:
Runtime.getRuntime().totalMemory();
Runtime.getRuntime().freeMemory();
EDIT: I forgot the main thing - add in your manifest, between application tag, this line:
android:largeHeap="true"

There are many problems with memory exceptions with bitmaps on Android, many of which are discussed on stackoverflow. It would probably be best if you went through the existing questions to see if yours matches one of the existing ones, then if not, write up what makes your situation different.
Some examples:
Out of memory exception due to large bitmap size
Android: out of memory exception in Gallery
Android handling out of memory exception on image processing
etc:
https://stackoverflow.com/search?q=android+out+of+memory+exception+bitmap

I have explained it in this blog post: android bitmap processing tips
Now here are tips which you can follow and can avoid out of memory exception in your Android Application.
Always use Activity context instead of Application context. because Application context cannot be garbage collected. And release resources as your activity finishes. (life cycle of object should be
same as of activity).
2 . When Activity finishes. Check HEAP DUMP (memory analysis tool in Android studio).
If there are objects in HEAP DUMP from finished activity there is memory leak. review your
code and identify what is causing memory leak.
Always use inSampleSize
Now what is inSampleSize ?
with the help of inSampleSize you are actually telling the decoder not to grab every pixel in memory, instead sub sample image.
This will cause less number of pixels to be loaded in memory than the original image. you can tell decoder to grab every 4th pixel or every second pixel from original image.
if inSampleSize is 4. decoder will return an Image that is 1/16 the number of pixels in original image.
so how much memory you have saved ? calculate :)
Read Bitmap Dimensions before loading into memory.
How reading bitmap dimensions before loading image into memory can help you avoid out of
memory error ? Let's Learn
use inJustBounds = true
here is technique with the help of which you can get image dimension beore loading it in memory
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.id.myimage, options);
int imageHeight = options.outHeight;
int imageWidth = options.outWidth;
String imageType = options.outMimeType;
Above code snippet will not give us any image/bitmap. it will return null for bitmap Object.
but it will definitely return width and height of that image. which is R.id.myimage.
Now you have width and height of Image. you can scale up or scale down image based on these factors:
ImageView size which will be used to display Image.
Available amount of memory. you can check available amount of memory using ActivityManager and getMemoryClass.
Screen size and density of device.
Use appropriate Bitmap Configuration
Bitmap configurations is color space/color depth of an Image. Default bitmap Configuration in Android is RGB_8888 which is 4 bytes per pixel.
If you use RGB_565 color channel which use 2 Bytes per pixel. half the memory allocation for same resolution :)
Use inBitmap property for recycling purpose.
Do not make static Drawable Object as it cannot be garbage collected.
Request large heap in in manifest file.
Use multiple processes if you are doing lot of image processing(memory intensive task) or use NDK (Native Development using c, c++)

You can try calling recycle() on the bitmap when you are done with it. This will clear all the image data and free up the memory. If anything tries to draw the bitmap after this then your app will crash. If you do get a crash it may help you find out what is still holding onto your bitmap.

This happens because you are loading the bitmap directly,which consumes a lot of memory.
Instead use a scaled down version of the picture in _profileBitmap.
This guy explains it pretty well.
http://androidcocktail.blogspot.in/2012/05/solving-bitmap-size-exceeds-vm-budget.html

With Larger images it can be avoided by sampling them into smaller size.
Use below example -
File f = new File(selectedImagePath);
// First decode with inJustDecodeBounds=true to check dimensions
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeStream(new FileInputStream(f), null, options);
// Calculate inSampleSize
options.inSampleSize = calculateInSampleSize(options, 720, 1280); //My device pixel resolution
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
Bitmap bmpPic = BitmapFactory.decodeStream(new FileInputStream(f), null, options);
Bitmap bmpPic1 = Bitmap.createBitmap(bmpPic, 0, 0, bmpPic.getWidth(), bmpPic.getHeight(), mat, true);
img.setImageBitmap(bmpPic1); //img is your ImageView
Reference-
http://developer.android.com/training/displaying-bitmaps/load-bitmap.html

You could use a vector Drawable . It uses an xml file to describe your image , so it consumes less memory.
To do that you should use the SVG format for your images and then generate the xml file using one of these 2 solutions :
Solution 1 : Use the vector asset studio in Android Studio : right click on Drawable file in your project -> new -> vector asset
Solution 2 : Use the svg2android website : https://inloop.github.io/svg2android
Check out this link for further information:
https://developer.android.com/studio/write/vector-asset-studio.html

I had the same issue when the phone was powered off and back on. Simply setting the bitmaps to null and calling System.gc(); fixed all the problems.

I had this issue because I was modifying a bitmap once, and then modifying the modified version a second time, resulting in three versions of the same bitmap (original, plus the two modified versions) being in memory at the same time.
I fixed it by changing my image-editing code to apply both modifications to the same bitmap as a kind of batch process, halving the number of modified versions that my app had to hold in memory.