crayfis/crayfis-android

Android version of the CRAYFIS app

crayfis-android's Issues

Replace Android ID indexing

The Android ID is an app-specific, rather than hardware-specific, identifier. As a result, a user who uninstalls and reinstalls the app or updates the Android OS will see their data linked to a new phone on the CRAYFIS website, and the weights/hotcells will be reset. We should either (1) index phones based on a hardware identifier although this is not recommended or (2) present users with a way to migrate their phones to a new Android ID.

Android 11

In August 2021, new releases are required to target Android 11. This prevents, without special permission, foreground services which access camera/location to be started in the background. Our AutoStart feature does exactly this, so we will need to either delete it or get permission from Google.

SDK 24 (Nougat) Improvements

Renderscript in Nougat can include reduction kernels, which will be more efficient for the RAW histogram and L2 processing. The Allocation.createAllocations() function can also be used to generate input buffers which share a bufferQueue, which may also improve performance for YUV (i.e. by passing the buffers directly through the Surface rather than through the grayscale() Renderscript kernel).

This has been tried before (see, for instance, this past snapshot) but in this implementation, different memory for the two Allocation usages caused inconsistent trigger results. For example, calling Allocation.copy2DRangeTo() immediately before and after Allocation.ioReceive() will typically yield different results for the old and new buffers, but occasionally the buffer values will not be changed; however, invoking a kernel on the Allocation will reflect the new buffer values.

Kill OpenCV?

OpenCV is an artifact of pre-Renderscript processing, and is currently only used for a few niche functions in the PRECALIBRATION state. While this has its advantages — the same OpenCV functions can be used in python on the server — this comes at the cost of a vastly inflated .apk size. If these operations can be efficiently performed without the OpenCV libraries, this would significantly reduce .apk size.