Store "source" (unprocessed captured image)

app/src/main/java/org/fairscan/app/MainActivity.kt

@@ -319,7 +319,7 @@ class MainActivity : ComponentActivity() {
         LaunchedEffect(Unit) {
             cameraViewModel.events.collect { event ->
                 when (event) {
-                    is CameraEvent.ImageCaptured -> viewModel.handleImageCaptured(event.jpegBytes)
+                    is CameraEvent.ImageCaptured -> viewModel.handleImageCaptured(event.page)
                 }
             }
         }

app/src/main/java/org/fairscan/app/MainViewModel.kt

@@ -27,9 +27,11 @@ import kotlinx.coroutines.flow.stateIn
 import kotlinx.coroutines.flow.update
 import kotlinx.coroutines.launch
 import org.fairscan.app.data.ImageRepository
+import org.fairscan.app.domain.CapturedPage
 import org.fairscan.app.ui.NavigationState
 import org.fairscan.app.ui.Screen
 import org.fairscan.app.ui.state.DocumentUiModel
+import java.io.ByteArrayOutputStream
 
 class MainViewModel(val imageRepository: ImageRepository, launchMode: LaunchMode): ViewModel() {
 
@@ -67,13 +69,17 @@ class MainViewModel(val imageRepository: ImageRepository, launchMode: LaunchMode
     }
 
     fun movePage(id: String, newIndex: Int) {
-        imageRepository.movePage(id, newIndex)
+        viewModelScope.launch {
-        _pageIds.value = imageRepository.imageIds()
+            imageRepository.movePage(id, newIndex)
+            _pageIds.value = imageRepository.imageIds()
+        }
     }
 
     fun deletePage(id: String) {
-        imageRepository.delete(id)
+        viewModelScope.launch {
-        _pageIds.value = imageRepository.imageIds()
+            imageRepository.delete(id)
+            _pageIds.value = imageRepository.imageIds()
+        }
     }
 
     fun startNewDocument() {
@@ -93,8 +99,19 @@ class MainViewModel(val imageRepository: ImageRepository, launchMode: LaunchMode
         return bytes?.let { BitmapFactory.decodeByteArray(it, 0, it.size) }
     }
 
-    fun handleImageCaptured(jpegBytes: ByteArray) {
+    fun handleImageCaptured(capturedPage: CapturedPage) {
-        imageRepository.add(jpegBytes)
+        viewModelScope.launch {
-        _pageIds.value = imageRepository.imageIds()
+            imageRepository.add(
+                compressJpeg(capturedPage.page, 75),
+                compressJpeg(capturedPage.source, 90)
+            )
+            _pageIds.value = imageRepository.imageIds()
+        }
+    }
+
+    private fun compressJpeg(bitmap: Bitmap, quality: Int): ByteArray {
+        val outputStream = ByteArrayOutputStream()
+        bitmap.compress(Bitmap.CompressFormat.JPEG, quality, outputStream)
+        return outputStream.toByteArray()
     }
 }

app/src/main/java/org/fairscan/app/data/ImageRepository.kt

@@ -19,6 +19,7 @@ import kotlinx.collections.immutable.toImmutableList
 import kotlinx.serialization.json.Json
 import java.io.File
 
+const val SOURCE_DIR_NAME = "sources"
 const val SCAN_DIR_NAME = "scanned_pages"
 const val THUMBNAIL_DIR_NAME = "thumbnails"
 
@@ -28,6 +29,10 @@ class ImageRepository(
     private val thumbnailSizePx: Int,
 ) {
 
+    private val sourceDir: File = File(scanRootDir, SOURCE_DIR_NAME).apply {
+        if (!exists()) mkdirs()
+    }
+
     private val scanDir: File = File(scanRootDir, SCAN_DIR_NAME).apply {
         if (!exists()) mkdirs()
     }
@@ -76,11 +81,12 @@ class ImageRepository(
 
     fun imageIds(): ImmutableList<String> = fileNames.toImmutableList()
 
-    fun add(bytes: ByteArray) {
+    fun add(pageBytes: ByteArray, sourceBytes: ByteArray? = null) {
         val fileName = "${System.currentTimeMillis()}.jpg"
         val file = File(scanDir, fileName)
-        file.writeBytes(bytes)
+        file.writeBytes(pageBytes)
         writeThumbnail(file)
+        sourceBytes?.let { File(sourceDir, fileName).writeBytes(sourceBytes) }
         fileNames.add(fileName)
         saveMetadata()
     }
@@ -158,6 +164,9 @@ class ImageRepository(
         scanDir.listFiles()?.forEach {
             file -> file.delete()
         }
+        sourceDir.listFiles()?.forEach {
+            file -> file.delete()
+        }
         saveMetadata() // "empty" json file
     }
 }

app/src/main/java/org/fairscan/app/domain/CapturedPage.kt

@@ -0,0 +1,23 @@
+/*
+ * Copyright 2025 Pierre-Yves Nicolas
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation, either version 3 of the License, or (at your option)
+ * any later version.
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package org.fairscan.app.domain
+
+import android.graphics.Bitmap
+
+data class CapturedPage(
+    val page: Bitmap,
+    val source: Bitmap
+)

app/src/main/java/org/fairscan/app/ui/screens/camera/CameraScreen.kt

@@ -84,6 +84,7 @@ import kotlinx.collections.immutable.toImmutableList
 import kotlinx.coroutines.delay
 import org.fairscan.app.MainViewModel
 import org.fairscan.app.R
+import org.fairscan.app.domain.CapturedPage
 import org.fairscan.app.ui.Navigation
 import org.fairscan.app.ui.Screen
 import org.fairscan.app.ui.components.CameraPermissionState
@@ -235,7 +236,8 @@ private fun CameraScreenScaffold(
             )
         }
         if (cameraUiState.captureState is CaptureState.CapturePreview) {
-            CapturedImage(cameraUiState.captureState.processed.asImageBitmap(), thumbnailCoords)
+            val page = cameraUiState.captureState.capturedPage.page
+            CapturedImage(page.asImageBitmap(), thumbnailCoords)
         }
     }
 }
@@ -461,7 +463,9 @@ fun CameraScreenPreview() {
 fun CameraScreenPreviewWithProcessedImage() {
     ScreenPreview(CaptureState.CapturePreview(
         debugImage("uncropped/img01.jpg"),
-        debugImage("gallica.bnf.fr-bpt6k5530456s-1.jpg")))
+        CapturedPage(
+            debugImage("gallica.bnf.fr-bpt6k5530456s-1.jpg"),
+            debugImage("gallica.bnf.fr-bpt6k5530456s-1.jpg"))))
 }
 
 @Preview(showBackground = true, widthDp = 640, heightDp = 320)

app/src/main/java/org/fairscan/app/ui/screens/camera/CameraViewModel.kt

@@ -31,6 +31,7 @@ import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 import org.fairscan.app.AppContainer
+import org.fairscan.app.domain.CapturedPage
 import org.fairscan.imageprocessing.Mask
 import org.fairscan.imageprocessing.Quad
 import org.fairscan.imageprocessing.detectDocumentQuad
@@ -40,10 +41,9 @@ import org.opencv.android.Utils
 import org.opencv.core.CvType
 import org.opencv.core.Mat
 import org.opencv.imgproc.Imgproc
-import java.io.ByteArrayOutputStream
 
 sealed interface CameraEvent {
-    data class ImageCaptured(val jpegBytes: ByteArray) : CameraEvent
+    data class ImageCaptured(val page: CapturedPage) : CameraEvent
 }
 
 class CameraViewModel(appContainer: AppContainer): ViewModel() {
@@ -88,7 +88,7 @@ class CameraViewModel(appContainer: AppContainer): ViewModel() {
         _captureState.value = CaptureState.Capturing(frozenImage)
     }
 
-    private fun onCaptureProcessed(captured: Bitmap?) {
+    private fun onCaptureProcessed(captured: CapturedPage?) {
         val current = _captureState.value
         _captureState.value = when {
             current is CaptureState.Capturing && captured != null ->
@@ -117,23 +117,25 @@ class CameraViewModel(appContainer: AppContainer): ViewModel() {
     fun onImageCaptured(imageProxy: ImageProxy?) {
         if (imageProxy != null) {
             viewModelScope.launch {
-                val image = processCapturedImage(imageProxy)
+                val source = imageProxy.toBitmap()
+                val processed = processCapturedImage(source, imageProxy.imageInfo.rotationDegrees)
                 imageProxy.close()
-                onCaptureProcessed(image)
+                onCaptureProcessed(processed?.let { CapturedPage(processed, source) })
             }
         } else {
             onCaptureProcessed(null)
         }
     }
 
-    private suspend fun processCapturedImage(imageProxy: ImageProxy): Bitmap? = withContext(Dispatchers.IO) {
+    private suspend fun processCapturedImage(
+        bitmap: Bitmap,
+        rotationDegrees: Int
+    ): Bitmap? = withContext(Dispatchers.IO) {
         var corrected: Bitmap? = null
-        val bitmap = imageProxy.toBitmap()
         val segmentation = imageSegmentationService.runSegmentationAndReturn(bitmap, 0)
         if (segmentation != null) {
             val mask = segmentation.segmentation
             var quad = detectDocumentQuad(mask, isLiveAnalysis = false)
-            val rotationDegrees = imageProxy.imageInfo.rotationDegrees
             if (quad == null) {
                 val now = System.currentTimeMillis()
                 lastSuccessfulLiveAnalysisState?.timestamp?.let {
@@ -157,14 +159,11 @@ class CameraViewModel(appContainer: AppContainer): ViewModel() {
         return@withContext corrected
     }
 
-    fun addProcessedImage(quality: Int = 75) {
+    fun addProcessedImage() {
         val current = _captureState.value
         if (current is CaptureState.CapturePreview) {
-            val outputStream = ByteArrayOutputStream()
-            current.processed.compress(Bitmap.CompressFormat.JPEG, quality, outputStream)
-            val jpegBytes = outputStream.toByteArray()
             viewModelScope.launch {
-                _events.emit(CameraEvent.ImageCaptured(jpegBytes))
+                _events.emit(CameraEvent.ImageCaptured(current.capturedPage))
             }
         }
         _captureState.value = CaptureState.Idle
@@ -184,7 +183,7 @@ sealed class CaptureState {
     data class CaptureError(override val frozenImage: Bitmap) : CaptureState()
     data class CapturePreview(
         override val frozenImage: Bitmap,
-        val processed: Bitmap,
+        val capturedPage: CapturedPage,
     ) : CaptureState()
 }