Handle padded camera rows in QR scanner (#6012)

Camera HALs may expose a Y plane whose row stride is wider than the visible image. Pass that stride to ZXing so padded rows remain aligned, and cover the vendor-layout case with a valid VLESS QR regression test.

V2rayNG/app/src/main/java/com/v2ray/ang/ui/ScannerActivity.kt

@@ -69,6 +69,7 @@ import com.v2ray.ang.ui.base.HelperBaseComponentActivity
 import com.v2ray.ang.ui.compose.AppTopBar
 import com.v2ray.ang.util.LogUtil
 import com.v2ray.ang.util.QRCodeDecoder
+import java.nio.ByteBuffer
 import java.util.concurrent.Executors
 import java.util.concurrent.atomic.AtomicBoolean
 import android.util.Size as TargetSize
@@ -410,15 +411,14 @@ private fun processImageProxy(
         return
     }
     try {
-        val buffer = imageProxy.planes[0].buffer
-        val bytes = ByteArray(buffer.remaining())
-        buffer.get(bytes)
         val width = imageProxy.width
         val height = imageProxy.height
-        val source = PlanarYUVLuminanceSource(
-            bytes, width, height,
-            0, 0, width, height,
-            false
+        val yPlane = imageProxy.planes[0]
+        val source = createYPlaneLuminanceSource(
+            buffer = yPlane.buffer,
+            width = width,
+            height = height,
+            rowStride = yPlane.rowStride,
         )
         val binaryBitmap = BinaryBitmap(HybridBinarizer(source))
         val hints = mapOf(
@@ -437,3 +437,26 @@ private fun processImageProxy(
         imageProxy.close()
     }
 }
+
+internal fun createYPlaneLuminanceSource(
+    buffer: ByteBuffer,
+    width: Int,
+    height: Int,
+    rowStride: Int,
+): PlanarYUVLuminanceSource {
+    val bufferCopy = buffer.duplicate()
+    val bytes = ByteArray(bufferCopy.remaining())
+    bufferCopy.get(bytes)
+    // Camera HALs may pad each Y row. ZXing advances rows by dataWidth, so the
+    // reported row stride must be used instead of the visible image width.
+    return PlanarYUVLuminanceSource(
+        bytes,
+        rowStride,
+        height,
+        0,
+        0,
+        width,
+        height,
+        false,
+    )
+}

V2rayNG/app/src/test/java/com/v2ray/ang/ui/ScannerActivityTest.kt

@@ -0,0 +1,48 @@
+package com.v2ray.ang.ui
+
+import com.google.zxing.BarcodeFormat
+import com.google.zxing.BinaryBitmap
+import com.google.zxing.DecodeHintType
+import com.google.zxing.MultiFormatReader
+import com.google.zxing.common.HybridBinarizer
+import com.google.zxing.qrcode.QRCodeWriter
+import org.junit.Assert.assertEquals
+import org.junit.Test
+import java.nio.ByteBuffer
+
+class ScannerActivityTest {
+
+    @Test
+    fun paddedCameraRowsDecodeQrCode() {
+        val payload = "vless://00000000-0000-4000-8000-000000006007@example.com:443" +
+            "?encryption=none&security=tls&type=tcp#issue-6007-gallery"
+        val width = 320
+        val height = 320
+        val rowStride = width + 32
+        val qrCode = QRCodeWriter().encode(payload, BarcodeFormat.QR_CODE, width, height)
+        val paddedYPlane = ByteArray(rowStride * height)
+
+        for (y in 0 until height) {
+            for (x in 0 until width) {
+                paddedYPlane[y * rowStride + x] = if (qrCode[x, y]) 0 else 0xFF.toByte()
+            }
+            for (x in width until rowStride) {
+                paddedYPlane[y * rowStride + x] = (x + y).toByte()
+            }
+        }
+
+        val source = createYPlaneLuminanceSource(
+            buffer = ByteBuffer.wrap(paddedYPlane),
+            width = width,
+            height = height,
+            rowStride = rowStride,
+        )
+        val hints = mapOf(
+            DecodeHintType.POSSIBLE_FORMATS to listOf(BarcodeFormat.QR_CODE),
+            DecodeHintType.TRY_HARDER to true,
+        )
+        val result = MultiFormatReader().decode(BinaryBitmap(HybridBinarizer(source)), hints)
+
+        assertEquals(payload, result.text)
+    }
+}