Skip to content

feat(liveness): Use backend-provided values for some FaceDectector values #191

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
Parent: feat(liveness): Add support for a no light liveness challenge
merged 1 commit into from
Sep 24, 2024
Merged

feat(liveness): Use backend-provided values for some FaceDectector values #191

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
14 changes: 8 additions & 6 deletions liveness/src/main/java/com/amplifyframework/ui/liveness/ml/FaceDetector.kt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -18,6 +18,7 @@ package com.amplifyframework.ui.liveness.ml
import android.content.Context
import android.graphics.RectF
import androidx.annotation.VisibleForTesting
import com.amplifyframework.predictions.aws.models.FaceTargetChallenge
import com.amplifyframework.predictions.aws.models.FaceTargetMatchingParameters
import com.amplifyframework.ui.liveness.R
import com.amplifyframework.ui.liveness.camera.LivenessCoordinator.Companion.TARGET_HEIGHT
Expand All @@ -42,10 +43,12 @@ internal class FaceDetector(private val livenessState: LivenessState) {
outputScores: Array<Array<FloatArray>>
): List<Detection> {
val detections = mutableListOf<Detection>()
val faceTargetChallenge = livenessState.faceTargetChallenge ?: return emptyList()
for (i in 0 until NUM_BOXES) {
var score = outputScores[0][i][0]
score = computeSigmoid(score)
if (score < MIN_SCORE_THRESHOLD) {

if (score < faceTargetChallenge.faceTargetMatching.faceDetectionThreshold) {
continue
}

Expand Down Expand Up @@ -159,6 +162,7 @@ internal class FaceDetector(private val livenessState: LivenessState) {
scaledMouth,
scaledLeftEar,
scaledRightEar,
faceTargetChallenge.faceTargetMatching.targetHeightWidthRatio
)
renormalizedDetections.add(
Detection(
Expand All @@ -183,13 +187,14 @@ internal class FaceDetector(private val livenessState: LivenessState) {
nose: Landmark,
mouth: Landmark,
leftEar: Landmark,
rightEar: Landmark
rightEar: Landmark,
heightWidthRatio: Float
): RectF {
val pupilDistance = calculatePupilDistance(leftEye, rightEye)
val faceHeight = calculateFaceHeight(leftEye, rightEye, mouth)

val ow = (ALPHA * pupilDistance + GAMMA * faceHeight) / 2
val oh = GOLDEN_RATIO * ow
val oh = heightWidthRatio * ow

val eyeCenterX = (leftEye.x + rightEye.x) / 2
val eyeCenterY = (leftEye.y + rightEye.y) / 2
Expand Down Expand Up @@ -450,7 +455,6 @@ internal class FaceDetector(private val livenessState: LivenessState) {

companion object {
private const val MIN_SUPPRESSION_THRESHOLD = 0.3f
private const val MIN_SCORE_THRESHOLD = 0.7f
private val strides = listOf(8, 16, 16, 16)
private const val ASPECT_RATIOS_SIZE = 1
private const val MIN_SCALE = 0.1484375f
Expand All @@ -459,7 +463,6 @@ internal class FaceDetector(private val livenessState: LivenessState) {
private const val ANCHOR_OFFSET_Y = 0.5f
private const val INPUT_SIZE_HEIGHT = 128
private const val INPUT_SIZE_WIDTH = 128
private const val GOLDEN_RATIO = 1.618f
private const val ALPHA = 2.0f
private const val GAMMA = 1.8f
const val X_SCALE = 128f
Expand All @@ -479,7 +482,6 @@ internal class FaceDetector(private val livenessState: LivenessState) {
* 14, 15 - right eye tragion
*/
const val NUM_COORDS = 16
const val INITIAL_FACE_DISTANCE_THRESHOLD = 0.32f

fun loadModel(context: Context): Interpreter {
val modelFileDescriptor =
Expand Down
2 changes: 1 addition & 1 deletion liveness/src/main/java/com/amplifyframework/ui/liveness/state/LivenessState.kt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -222,7 +222,7 @@ internal data class LivenessState(
leftEye, rightEye, mouth,
LivenessCoordinator.TARGET_WIDTH, LivenessCoordinator.TARGET_HEIGHT
)
if (faceDistance >= FaceDetector.INITIAL_FACE_DISTANCE_THRESHOLD) {
if (faceDistance >= faceTargetChallenge!!.faceTargetMatching.faceDistanceThresholdMin) {
livenessCheckState =
LivenessCheckState.Initial.withMoveFaceFurtherAwayMessage()
} else {
Expand Down
6 changes: 3 additions & 3 deletions liveness/src/test/java/com/amplifyframework/ui/liveness/ml/FaceDetectorTest.kt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -37,8 +37,7 @@ internal class FaceDetectorTest {
private val mouth = Landmark(0.5062596f, 0.68926525f)
private val leftEar = Landmark(0.78989476f, 0.5973732f)
private val rightEar = Landmark(0.16585289f, 0.5668279f)
private val width = 0.65490234f
private val height = 0.49117205f
private val heightWidthRatio = 1.618f

@Before
fun setup() {
Expand Down Expand Up @@ -68,7 +67,8 @@ internal class FaceDetectorTest {
nose,
mouth,
leftEar,
rightEar
rightEar,
heightWidthRatio
)

// then
Expand Down