Android image capturing and scaling - android

I am using the Camera activity to capture the JPEG image. After image is saved and the controll is returned back to my application activity I would like to to determine the captured JPEG image dimensions without loading the whole image into memory via Bitmap object - can it be easily done somehow?
Is there any class, which reads the JPEG header and give me such information? I would like to avoid OOM conditions - but might be it is not a problem to load the whole image into memory - is it?
After knowing the dimensions I would like to use BitmapFactory to scale the image.
Thanks a lot
Kind Regards,
STeN

Perhaps a work-around (see 2nd approach) by setting the quality?
bmp.compress(CompressFormat.JPEG, 75,
pfos);
You would have to do a trial run to see what size the quality gets you though...
*The first approach creates a log file to get the width and height but not sure if you wanted the extra step of looking at a log file.

You can use the ExifInterface class to read the image width and height.

Related

How to increase Image Memory using Bitmap Factory option

I want to use Big Size Image In Back Ground so How Can I do And i want to It's Working For All Device
As per your requirement, I guess that you are getting image from server end. Some time big size Bitmap throw OutOfMemoryException. So do one thing. Use this library to compress image and then show it to ImageView.
https://github.com/zetbaitsu/Compressor
You can also use Library. It provide you facility to fix image size and quality. so it won't be problem for you.
Nostra Image Loader

Saving Bitmap Image without shrinking width and height

What im trying to do is to save an edited bitmap that is composed by 2 bitmaps overlayed. My application allows the user to draw on top of a picture and save it.
My problem is: when i save the result image, it gets smaller, even setting the quality to 100. So, if the user saves and edit the image multiple times, the image will get smaller and smaller.
I save the bitmap with this:
result.compress(Bitmap.CompressFormat.JPEG, 100, fos);
I debugged the code, and at this point the width and height are fine, but after saving, the image shrinks.
I've researched for questions about this, but the ones i've found had no answers that could help me.
What i need is a way to save a bitmap without shrinking it, but i need it to be in image format, like JPG, PNG, etc.
Thanks in advance.
I guess is not at the time when you are saving the image, the issue is when you are editing the image (creating layers). Check that mechanism, maybe you are setting the image size there.

Android imageview image quality matter?

I am writing a Android app which need to display some high quality picture(took from professional DSLR). The problem is it can't be display from gallery.
I choose a photo in Gallery first. The target picture is 2464*1632 JPEG, roughly 4.5M;
Then I just need to compress it to 800*600 and display it in imageview:
image.setImageBitmap(this.bmp);
Thing is that I have tested other image I downloaded form internet(really low quality), and it works without any problem. Can anybody tell me why it can't be displayed? I will be really appericiated
Large images are tricky to handle due to limited memory. You have several choices:
Use a WebView (this allows you to have pinch and zoom functionality to make use of those extra pixels
Decode the image down to the size of the display and then put it in an ImageView using BitmapOpts http://developer.android.com/reference/android/graphics/BitmapFactory.Options.html and changing inSampleSize. It seems you may be having difficulty with that, so consider using createScaledBitmap which just needs the dest width and height.

BitmapFactory.decodeFileDescriptor

I need to upload a large image. The right way would be to use BitmapFactory.decodeFileDescriptor with inSampleSize options. But the problem, that the image is still to big to fit in memory on some devices. Is there a way, to somehow recieve an InputStream of a scaled image instead of bitmap?
Or can you suggest any other way?
Always the best place to start is the provided documentation.. they provide sample code of how to Displaying Bitmaps Efficiently
start from here, it'll help you Load Large Bitmaps Efficiently

Access to separate pixel of JPEG image in Android

In my android project I need to get access for each separate pixel of JPEG image. Image created by built-in photo application. I try to convert JPEG into Bitmap class instance, but OutOfMemoryException was thrown. After searching info about this problem I have found the following solution: resize image! But quality of image is important in my project, and i can't resize it. Is there any way to get each-pixel access?
if your image is too big and the quality is important i suppose the best way is to use or create your own class to cut the image in zone (eg : 50*50 px) , there is several jpeg info class in the internet to help you understand how work jpeg files.
Have you tried BufferedImage ? (it's not in the sdk but maybe usable)
The nature of jpeg makes it very hard to get the value of a single pixel. The main reason is that the data is not byte aligned, another is that everything is encoded in blocks that can be of sizes 8x16, 16x8 and 8x8. Also, you need to handle subsampling of chroma values.
If the image contains restart markers, maybe you can skip into the image so you don't have to decode the whole image before getting the pixel value.

Categories

Resources