Develop Reference

Android: Display camera still capture on TextureView Quickly?

I'm using the Android Camera2 API to take still capture images and displaying them on a TextureView (for later image editing).
I have been scouring the web for a faster method to:
Decode Camera Image buffer into bitmap
Scale bitmap to size of screen and rotate it (since it comes in rotated 90 degrees)
Display it on a texture view
Currently I've managed an execution time of around 0.8s for the above, but this is too long for my particular application.
A few solutions I've considered were:
Simply taking a single frame of the preview (timing-wise this was fast, except that I had no control over auto flash)
Trying to get instead a YUV_420_888 formatted image and then somehow turning that into a bitmap (there's a lot of stuff online that might help but my initial attempts bore no fruit as of yet)
Simply sending a reduced quality image from the camera itself, but from what I've read it looks like the JPEG_QUALITY parameter in CaptureRequests does nothing! I've also tried setting BitmapFactory options inSampleSize but without any noticeable improvement in speed.
Finding some way to directly manipulate the jpeg byte array from image buffer to transform it and then converting to bitmap, all in one shot
For your reference, the following code takes the image buffer, decodes and transforms it, and displays it on the textureview:
Canvas canvas = mTextureView.lockCanvas();
// obtain image bytes (jpeg) from image in camera fragment
// mFragment.getImage() returns Image object
ByteBuffer buffer = mFragment.getImage().getPlanes()[0].getBuffer();
byte[] bytes = new byte[buffer.remaining()];
buffer.get(bytes);
// decoding process takes several hundred milliseconds
Bitmap src = BitmapFactory.decodeByteArray(bytes, 0, bytes.length);
mFragment.getImage().close();
// resize horizontally oriented images
if (src.getWidth() > src.getHeight()) {
// transformation matrix that scales and rotates
Matrix matrix = new Matrix();
if (CameraLayout.getFace() == CameraCharacteristics.LENS_FACING_FRONT) {
matrix.setScale(-1, 1);
}
matrix.postRotate(90);
matrix.postScale(((float) canvas.getWidth()) / src.getHeight(),
((float) canvas.getHeight()) / src.getWidth());
// bitmap creation process takes another several hundred millis!
Bitmap resizedBitmap = Bitmap.createBitmap(
src, 0, 0, src.getWidth(), src.getHeight(), matrix, true);
canvas.drawBitmap(resizedBitmap, 0, 0, null);
} else {
canvas.drawBitmap(src, 0, 0, null);
}
// post canvas to texture view
mTextureView.unlockCanvasAndPost(canvas);
This is my first question on stack overflow, so I apologize if I haven't quite followed common conventions.
Thanks in advance for any feedback.

If all you're doing with this is to draw it into a View, and won't be saving it, have you tried to simply request JPEGs that are lower resolution than maximum, and match the screen dimensions better?
Alternatively, if you need the full-size image, JPEG images typically contain a thumbnail - extracting that and displaying it is a lot faster than processing the full-resolution image.
In terms of your current code, if possible, you should avoid having to create a second Bitmap with the scaling. Could you instead place an ImageView on top of your TextureView when you want to display the image, and then rely on its built-in scaling?
Or use Canvas.concat(Matrix) instead of creating the intermediate Bitmap?

How to rotate the bitmap in android by using c/c++ native code

In My Business card reader android application , i got high resolution image/large size image, when i was rotation the that image, it will take more time some times it will show outOfMemory exception. so please help me to rotate image bitmap in C/C++ native code.`
I use below code for image rotating.
private Bitmap rotateBitmap(Bitmap source, int angle) {
Matrix matrix = new Matrix();
matrix.postRotate(angle);
Bitmap createBitmap = Bitmap.createBitmap(source, 0, 0,
source.getWidth(), source.getHeight(), matrix, true);
source.recycle();
return createBitmap;
}
`

Image rotation happens only in native code, so need to rewrite the same thing, you need to improve your implementation, it will be good if you share some piece of code

Have a look at solution for OutOfMemoryError:bitmap in stackoverflow you might find something there. And post your answer if you find something(I realy wonder how you deal with that:) )
I found some nice explanations when searching in google like outofmemoryexception bitmap android
and a tutorial on avoid outofmemroyexception while scaling image

Converting Bitmap in memory to Bitmap with Bitmap.Config.RGB_565

I have a loaded Bitmap which I would like to convert to set the config to Bitmap.Config.RGB_565. Is there a simple way of converting a Bitmap to this configuration after the Bitmap is already loaded into memory? For example, below I have a bitmap being decoded from the application resources, however, how would I convert an already loaded Bitmap to RGB_565? I'm sure it's something simple, however, I'm fairly new to working with Bitmaps and after a few hours of looking online, unfortunately I couldn't find what I needed specifically.
BitmapFactory.Options options = new BitmapFactory.Options();
options.inPreferredConfig=Bitmap.Config.RGB_565
bitmap=BitmapFactory.decodeResource(getResources(), R.drawable.myphoto ,options);

You can also try this:
Bitmap converted = original.copy(Config.RGB_565, false);
From the documentation of Bitmap.copy():
Tries to make a new bitmap based on the dimensions of this bitmap, setting the new bitmap's config to the one specified, and then copying this bitmap's pixels into the new bitmap. If the conversion is not supported, or the allocator fails, then this returns NULL.
Looking through the native source code, you should be fine converting between any values of Bitmap.Config.

I haven't tested this but it should work:
private Bitmap convert(Bitmap bitmap, Bitmap.Config config) {
Bitmap convertedBitmap = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), config);
Canvas canvas = new Canvas(convertedBitmap);
Paint paint = new Paint();
paint.setColor(Color.BLACK);
canvas.drawBitmap(bitmap, 0, 0, paint);
return convertedBitmap;
}
call the methods like this:
Bitmap convertedBitmap = convert(bitmap, Bitmap.Config.RGB_565);
You can do all kinds of additional transformations like rotating, stretching etc. if you use the drawBitmap with a Matrix.

Found the answer here https://stackoverflow.com/a/12148450/1364673, thanks to
siliconeagle.
The solution is to create a new bitmap with the required encoding as per link above example.

Merging image from camera with image from drawables

I´m trying to merge 2 images, one is bitmap from camera, second one is .png file stored in drawables. What I did was that I used both images as bitmaps and I tried to merge them by using canvas, something like this:
Bitmap topImage = BitmapFactory.decodeFile("gui.png");
Bitmap bottomImage = BitmapFactory.decodeByteArray(arg0, 0, arg0.length);
Canvas canvas = new Canvas(bottomImage);
canvas.drawBitmap(topImage, 0, 0, null);
But I keep getting "Bitmap size exceeds VM budget" error all the time. I tried nearly everything, but still, it keeps throwing this error. Is there another way of merging 2 images? What i need to do is simple - I need to take photo and save it merged with that .PNG image stored in drawables. For example this app is very close to what i need - https://play.google.com/store/apps/details?id=com.hl2.hud&feature=search_result#?t=W251bGwsMSwyLDEsImNvbS5obDIuaHVkIl0.
Thanks :)

See the below code for combining two images.
This method returns combined bitmap
public Bitmap combineImages(Bitmap frame, Bitmap image) {
Bitmap cs = null;
Bitmap rs = null;
rs = Bitmap.createScaledBitmap(frame, image.getWidth() + 50,
image.getHeight() + 50, true);
cs = Bitmap.createBitmap(rs.getWidth(), rs.getHeight(),
Bitmap.Config.RGB_565);
Canvas comboImage = new Canvas(cs);
comboImage.drawBitmap(image, 25, 25, null);
comboImage.drawBitmap(rs, 0, 0, null);
if (rs != null) {
rs.recycle();
rs = null;
}
Runtime.getRuntime().gc();
return cs;
}
You can change height and width as per your requirements
Hope this will help...

How large are the images? I've only encountered this problem when trying to load large images into memory.
Is the byte array your decoding actually an image?
From a quick look at the android docs you can capture an image using the default camera app which may work in this situation.
http://developer.android.com/training/camera/photobasics.html
Also see this question: Capture Image from Camera and Display in Activity
Edit: You may also need to scale the image from the camera down if it is very large. See the end of the android page I linked to for details on that.

Android bitmap quality issues

In my app, the bitmap is drawn as if the color is some lower quality type. If i load up the background image using the gallery app, it loads just fine and does not look like it's super low quality. The code i am using to load and draw my images is simple:
//Code for initializing the Bitmap
Bitmap bitmap = Bitmap.createScaledBitmap(BitmapFactory.decodeResource(getResources(), R.drawable.none), (int) (canvas.getWidth() * compression), (int) (canvas.getHeight() * compression), true);
//...
//Code for drawing this Bitmap
canvas.drawBitmap(bitmap, null, new RectF(0, 0, canvas.getWidth(), canvas.getHeight()), null);
If nothing in the code tells you what is wrong, i made an image comparing what the image actually looks like on a computer or other image viewer, and what it looks like in the app.

question is somewhat similar to Bad image quality after resizing/scaling bitmap
try disabling scaling, resize in an offscreen bitmap and make sure that Bitmap is 32 bits (ARGB888):
Options options = new BitmapFactory.Options();
options.inScaled = false;
options.inDither = false;
options.inPreferredConfig = Bitmap.Config.ARGB_8888;
Bitmap source = BitmapFactory.decodeResource(a.getResources(), path, options);
another good and complete answer about image scaling/processing can be found at Quality problems when resizing an image at runtime