1 /*
<lambda>null2 * Copyright (C) 2021 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 package com.example.testapp
18
19 import android.renderscript.toolkit.Range2d
20
21 /**
22 * Reference implementation of a Convolve operation.
23 */
24 @ExperimentalUnsignedTypes
25 fun referenceConvolve(
26 inputArray: ByteArray,
27 vectorSize: Int,
28 sizeX: Int,
29 sizeY: Int,
30 coefficients: FloatArray,
31 restriction: Range2d?
32 ): ByteArray {
33 val input = Vector2dArray(inputArray.asUByteArray(), vectorSize, sizeX, sizeY)
34 val radius = when (coefficients.size) {
35 9 -> 1
36 25 -> 2
37 else -> {
38 throw IllegalArgumentException("RenderScriptToolkit Convolve. Only 3x3 and 5x5 convolutions are supported. ${coefficients.size} coefficients provided.")
39 }
40 }
41
42 input.clipReadToRange = true
43 val output = input.createSameSized()
44 input.forEach(restriction) { x, y ->
45 output[x, y] = convolveOne(input, x, y, coefficients, radius)
46 }
47 return output.values.asByteArray()
48 }
49
50 @ExperimentalUnsignedTypes
convolveOnenull51 private fun convolveOne(
52 inputAlloc: Vector2dArray,
53 x: Int,
54 y: Int,
55 coefficients: FloatArray,
56 radius: Int
57 ): UByteArray {
58 var sum = FloatArray(paddedSize(inputAlloc.vectorSize))
59 var coefficientIndex = 0
60 for (deltaY in -radius..radius) {
61 for (deltaX in -radius..radius) {
62 val inputVector = inputAlloc[x + deltaX, y + deltaY]
63 sum += inputVector.toFloatArray() * coefficients[coefficientIndex]
64 coefficientIndex++
65 }
66 }
67 return sum.clampToUByte()
68 }
69