Convert YUV to RGB from camera directly

RgbConversion.kt

package com.netvirta.curvecapturescanner

import android.graphics.ImageFormat
import android.renderscript.Allocation
import android.renderscript.Element
import android.renderscript.RenderScript
import android.renderscript.ScriptIntrinsicYuvToRGB
import android.renderscript.Type
import android.util.Log
import android.util.Size
import android.view.Surface

class RgbConversion(rs: RenderScript, private val mSizeVideoCall: Size) : Allocation.OnBufferAvailableListener {
    private var mInputAllocation: Allocation? = null
    private var mOutputAllocation: Allocation? = null
    private val mScriptC: ScriptIntrinsicYuvToRGB
    private val TAG = RgbConversion::class.java.simpleName
    val inputSurface: Surface
        get() = mInputAllocation!!.surface

    init {

        createAllocations(rs)

        mInputAllocation!!.setOnBufferAvailableListener(this)

        mScriptC = ScriptIntrinsicYuvToRGB.create(rs, Element.U8_4(rs))
    }

    private fun createAllocations(rs: RenderScript) {

        val width = mSizeVideoCall.width
        val height = mSizeVideoCall.height


        val yuvTypeBuilder = Type.Builder(rs, Element.U8_4(rs))
        yuvTypeBuilder.setX(width)
        yuvTypeBuilder.setY(height)

        yuvTypeBuilder.setYuvFormat(ImageFormat.YUV_420_888)

        mInputAllocation = Allocation.createTyped(rs, yuvTypeBuilder.create(),
                Allocation.USAGE_IO_INPUT or Allocation.USAGE_SCRIPT)

        val rgbType = Type.createXY(rs, Element.RGBA_8888(rs), width, height)

        mOutputAllocation = Allocation.createTyped(rs, rgbType,
                Allocation.USAGE_IO_OUTPUT or Allocation.USAGE_SCRIPT)

    }

    fun setOutputSurface(output: Surface) {
        mOutputAllocation!!.surface = output
    }

    override fun onBufferAvailable(a: Allocation) {
        // Get the new frame into the input allocation
        val startTime = System.currentTimeMillis()
        a.ioReceive()

        mScriptC.setInput(a)
        mScriptC.forEach(mOutputAllocation)

        mOutputAllocation!!.ioSend()
        val endTime1 = System.currentTimeMillis()
        Log.d(TAG, """processImage: put memory: ${endTime1 - startTime}ms""")
    }
}