loading a bitmap to the "right" size - android

i want to load a bitmap off the SD card and display it. the image on the SD card is 2592x1728, and i want to display this image in a 200x200 pixel image. when i load the image, obviously, I don't want to load the entire image into memory (2592x1728x3 bytes!). is there a way to automatically load it into the right size?

Take a look at this snippet. Its about as good as it gets. You will have to read over the whole image at least once, but you can scale it down to a Bitmap object that is a little bit less cumbersome to work with.
Strange out of memory issue while loading an image to a Bitmap object

Related

Load Very Large Bitmap

I'm taking whole screenshot of a WebView and display the bitmap on an ImageView. The bitmap can be 7 screen height. (E.g. 1440x14000 px)
I'm frequently face with
OutOfMemoryError.
I've seen this
This says that load a scaled down version into memory but I don't want to lose image quality. There are the same approaches on the web.
Is there any way to handle OutOfMemoryError without loading scaled down version?
The bitmap can be 7 screen height. (E.g. 1440x14000 px)
Note that this means that the user cannot see the whole image at once at full resolution.
I'm frequently face with OutOfMemoryError
On most devices, you will have a very difficult time loading an image that large, as you cannot get a single contiguous memory block that big.
This says that load a scaled down version into memory but I don't want to lose image quality
To some extent, you do not have much of a choice. If you want the user to see the full extent of the picture at once, the image has to be scaled to fit the screen.
Is there any way to handle OutOfMemoryError without loading scaled down version?
There are ImageView replacements that offer pan and zoom. Some of those, such as this one, handle loading in pieces of the image at a time, with whatever scaling is necessary for the current zoom level, to make it more likely that you will be able to show the user the entire image.
It is not a solution, of course, but I'm also not familiar with your exact needs, so maybe this may help you a little - you can try to play with bitmap options during decoding. Try to use Bitmap.Config.inPreferredConfig as RGB_565 - this will reduce size of your bitmap twice comparing to default ARGB_8888. But, of course, if you use complex images in your web page this may reduce their quality.

Loading images into big size imageviews

I know that ,according to android docs, that if you have a big image. Then you scale it down to size of the image view you are loading it to (using the decodeResources and Options class).
Now my question is, lets say you want to load background picture and the source image is of similar size, do you just load the image? Or do you actually scale it down a bit and then using the FITXY to stretch it?
I am trying to avoid Out Of Memory exceptions here
Thank you

how device gallery show large images?

Whenever I try to show large size(1 MB) bitmap in imageview, system throw OutOfMemory exception.
If I place 7-8 MB image, gallery can easily show that image.
Just want to know How device default gallery is able to show large image in easy way?
Which mechanism is used by device gallery?
Generally speaking, they subsample the image. A 1MB PNG or JPEG file will be much higher resolution than the screen, and so it is wasteful to load the whole image in. Subsampling allows you to load the image in much closer to the actual size of the ImageView you will use, allowing it to fit in memory better. A simple approach to subsampling involves using inSampleSize on BitmapFactory.Options; Dave Morrissey's SubsamplingScaleImageView offers pinch-to-zoom and such while peforming subsampling (note: I have not tried this component, as I just ran across it a minute ago).

Android Efficient Bitmap processing

My scenario:
In my activity, I have to show 2 galleries, 1 with large image and another is a thumbnail(same exactly like default Gallery application).
My doubts:
I am planning to save as 2 images(1 with large size and another one with thumbnail size) in sdcard for fast processing. Is that good practice? since it will increase the size.
Or Shall I resize the large image during the getView method of BaseAdapter to small size for displaying in thumbnail gallery?
Which one is the good practice? I don't want to slow down my app.
See this example.
I will suggest you that, put only your large image inside your sdcard. But at runtime, Android provides a good facility to get Thumbnails using MediaStore.Images.Thumbnails.
Edit:
You can also get use Loading Sample Sized Bitmap. This will first create a sample size of your requirement. Then will give you a Thumbnail sized Bitmap.
StackOverflowAnswers:
1) Get thumbnail of image on SD card

Is there a way to crop a large image on android without loading into memory?

I don't want to display the bitmap on the screen. Just trying to create a max square image out of the original image from sdcard and then uploading to server. Is there a way to crop an image without loading the image into memory? or load the image in chunks and then save to file?
I don't know if I understand well the question but this could help:
http://developer.android.com/reference/android/graphics/BitmapRegionDecoder.html
BitmapRegionDecoder can be used to decode a rectangle region from an image. BitmapRegionDecoder is particularly useful when an original image is large and you only need parts of the image.
Hope to help :)

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