I'm intending to display very large Images in Android.
My first solution - to supply them as pdf - fails because not every handheld got a pdf-viewer preinstalled, and I don't want to require the users to install one.
So I have a png now (width = 3998px height=2827px) that I want to display. I downloaded this image to test how it would be displayed the gallery. It was quite painful. It seems that the galery renders this picture only once, and if I Zoom in, I cannot read the text at all.
So I wrote a testActivity which simply has an ImageView nested in a LinearLayout. I put the image into the drawable and set it as ImageView's image-source.
Unforunately the app crashes immediatly, due to an "
ERROR/AndroidRuntime(8906): Caused by: java.lang.OutOfMemoryError: bitmap size exceeds VM budget"
I didn't expect that ONE single Image can be too large forVM's memory
. I played a little bit around, set ImageViews
size to 3998 & 2827px
, put the Image to sdCard
and read it manually with a fileInputStream
.
To my big surprise it now shows my image, but if I turn my Nexus S horizontal I get the same OutOfMemoryError
as before.
Can somewone point me the main difference between recieving a Bitmap through a FileInputStream
or to set it as ImageView's
source.
Also I'm not able to scroll comfortable with two parent scrollViews
I searching for a simple solution to display ONE large image
at a time with the ability to scroll horizontal and vertical
while able to zoom in and out.
here is a sample of the image I want to display
I know it's an old post but I spent a lot of time on this problem, so here's my solution.
I wanted to display a 2000×3000 picture but I got out of memory or the image was too large to be displayed.
To begin, I get the dimensions of the picture:
o = new BitmapFactory.Options();
o.inJustDecodeBounds=true;
pictures = BitmapFactory.decodeStream(new FileInputStream(f), null, o);
Then I cut it up into four parts and displayed them with four ImageViews.
I tried to load the full picture and cut it into four (using BitmapFactory.create(bitmap,int,int,int,int)
) but got out of memory again.
So I decided to use some BitMapRegionDecoder:
for (int i = 0; i < 2; i++) {
for (int j = 0; j < 2; j++) {
ImageView iv = new ImageView(this);
InputStream istream = null;
try {
istream = this.getContentResolver().openInputStream(Uri.fromFile(f));
} catch (FileNotFoundException e1) {
e1.printStackTrace();
}
BitmapRegionDecoder decoder = null;
try {
decoder = BitmapRegionDecoder.newInstance(istream, false);
} catch (IOException e) {
e.printStackTrace();
}
int nw = (j*width/k);
int nh = (i*height/k);
Bitmap bMap = decoder.decodeRegion(new Rect(nw,nh, (nw+width/k),(nh+height/k)), null);
iv.setImageBitmap(bMap);
}
}
This worked.