Générer des images avec Imagen

dependencies {
  // Import the BoM for the Firebase platform
  implementation(platform("com.google.firebase:firebase-bom:34.4.0"))

  // Add the dependency for the Firebase AI Logic library. When using the BoM,
  // you don't specify versions in Firebase library dependencies
  implementation("com.google.firebase:firebase-ai")
}

val imagenModel = Firebase.ai(backend = GenerativeBackend.vertexAI())
.imagenModel("imagen-3.0-capability-001")

import androidx.compose.ui.graphics.Color as ComposeColor
[...]

@Composable
fun ImagenEditingMaskEditor(
    sourceBitmap: Bitmap,
    onMaskFinalized: (Bitmap) -> Unit,
) {

    val paths = remember { mutableStateListOf<Path>() }
    var currentPath by remember { mutableStateOf<Path?>(null) }
    var scale by remember { mutableFloatStateOf(1f) }
    var offsetX by remember { mutableFloatStateOf(0f) }
    var offsetY by remember { mutableFloatStateOf(0f) }

    Column(
        modifier = Modifier.fillMaxSize(),
    ) {
        Box(
            modifier = Modifier
                .fillMaxWidth()
                .pointerInput(Unit) {
                    detectDragGestures(
                        onDragStart = { startOffset ->
                            val transformedStart = Offset(
                                (startOffset.x - offsetX) / scale,
                                (startOffset.y - offsetY) / scale,
                            )
                            currentPath = Path().apply { moveTo(transformedStart.x, transformedStart.y) }
                        },
                        onDrag = { change, _ ->
                            currentPath?.let {
                                val transformedChange = Offset(
                                    (change.position.x - offsetX) / scale,
                                    (change.position.y - offsetY) / scale,
                                )
                                it.lineTo(transformedChange.x, transformedChange.y)
                                currentPath = Path().apply { addPath(it) }
                            }
                            change.consume()
                        },
                        onDragEnd = {
                            currentPath?.let { paths.add(it) }
                            currentPath = null
                        },
                    )
                },
        ) {
            Image(
                bitmap = sourceBitmap.asImageBitmap(),
                contentDescription = null,
                modifier = Modifier.fillMaxSize(),
                contentScale = ContentScale.Fit,
            )
            Canvas(modifier = Modifier.fillMaxSize()) {
                val canvasWidth = size.width
                val canvasHeight = size.height
                val bitmapWidth = sourceBitmap.width.toFloat()
                val bitmapHeight = sourceBitmap.height.toFloat()
                scale = min(canvasWidth / bitmapWidth, canvasHeight / bitmapHeight)
                offsetX = (canvasWidth - bitmapWidth * scale) / 2
                offsetY = (canvasHeight - bitmapHeight * scale) / 2
                withTransform(
                    {
                        translate(left = offsetX, top = offsetY)
                        scale(scale, scale, pivot = Offset.Zero)
                    },
                ) {
                    val strokeWidth = 70f / scale
                    val stroke = Stroke(width = strokeWidth, cap = StrokeCap.Round, join = StrokeJoin.Round)
                    val pathColor = ComposeColor.White.copy(alpha = 0.5f)
                    paths.forEach { path ->
                        drawPath(path = path, color = pathColor, style = stroke)
                    }
                    currentPath?.let { path ->
                        drawPath(path = path, color = pathColor, style = stroke)
                    }
                }
            }
        }
        Button(
            onClick = {
                val maskBitmap = createMask(sourceBitmap, paths)
                onMaskFinalized(maskBitmap)
            },
        ) {
            Text("Save mask")
        }
    }
}

import android.graphics.Color as AndroidColor
import android.graphics.Paint
[...]

private fun createMaskBitmap(
    sourceBitmap: Bitmap,
    paths: SnapshotStateList<Path>,
): Bitmap {
    val maskBitmap = createBitmap(sourceBitmap.width, sourceBitmap.height)
    val canvas = android.graphics.Canvas(maskBitmap)
    val paint = Paint().apply {
        color = AndroidColor.RED
        strokeWidth = 70f
        style = Paint.Style.STROKE
        strokeCap = Paint.Cap.ROUND
        strokeJoin = Paint.Join.ROUND
        isAntiAlias = true
    }
    paths.forEach { path -> canvas.drawPath(path.asAndroidPath(), paint) }

    return maskBitmap
}

suspend fun insertFlowersIntoImage(
  model: ImagenModel,
  originalImage: Bitmap,
  mask: ImagenMaskReference): ImagenGenerationResponse<ImagenInlineImage> {
    val prompt = "a vase of flowers"

    // Pass the original image, a mask, the prompt, and an editing configuration.
    val editedImage = model.editImage(
        sources = listOf(
            ImagenRawImage(originalImage),
            mask),
        prompt = prompt,
        // Define the editing configuration for inpainting and insertion.
        config = ImagenEditingConfig(ImagenEditMode.INPAINT_INSERTION)
    )

    return editedImage
}

suspend fun removeBallFromImage(model: ImagenModel, originalImage: Bitmap, mask: ImagenMaskReference): ImagenGenerationResponse<ImagenInlineImage> {

    // Optional: provide the prompt describing the content to be removed.
    val prompt = "a ball"

    // Pass the original image, a mask, the prompt, and an editing configuration.
    val editedImage = model.editImage(
        sources = listOf(
            ImagenRawImage(originalImage),
            mask
        ),
        prompt = prompt,
        // Define the editing configuration for inpainting and removal.
        config = ImagenEditingConfig(ImagenEditMode.INPAINT_REMOVAL)
    )

    return editedImage
}

suspend fun expandImage(originalImage: Bitmap, imagenModel: ImagenModel): ImagenGenerationResponse<ImagenInlineImage> {

    // Optionally describe what should appear in the expanded area.
    val prompt = "a sprawling sandy beach next to the ocean"

    val editedImage = model.outpaintImage(
        ImagenRawImage(originalImage),
        Dimension(width, height),
        prompt = prompt,
        newPosition = ImagenImagePlacement.LEFT_CENTER
    )


    return editedImage
}

suspend fun replaceBackground(model: ImagenModel, originalImage: Bitmap): ImagenGenerationResponse<ImagenInlineImage> {
    // Provide the prompt describing the new background.
    val prompt = "space background"

    // Pass the original image, a mask, the prompt, and an editing configuration.
    val editedImage = model.editImage(
        sources = listOf(
            ImagenRawImage(originalImage),
            ImagenBackgroundMask(),
        ),
        prompt = prompt,
        config = ImagenEditingConfig(ImagenEditMode.INPAINT_INSERTION)
    )

    return editedImage
}

suspend fun customizeCatImage(model: ImagenModel, referenceCatImage: Bitmap): ImagenGenerationResponse<ImagenInlineImage> {

    // Define the subject reference using the reference image.
    val subjectReference = ImagenSubjectReference(
        image = referenceCatImage,
        referenceID = 1,
        description = "cat",
        subjectType = ImagenSubjectReferenceType.ANIMAL
    )

    // Provide a prompt that describes the final image.
    // The "[1]" links the prompt to the subject reference with ID 1.
    val prompt = "A cat[1] flying through outer space"

    // Use the editImage API to perform the subject customization.
    val editedImage = model.editImage(
        references = listOf(subjectReference),
        prompt = prompt,
        config = ImagenEditingConfig(
            editSteps = 50 // Number of editing steps, a higher value can improve quality
        )
    )

    return editedImage
}

suspend fun customizeCatImageByControl(model: ImagenModel, referenceCatImage: Bitmap): ImagenGenerationResponse<ImagenInlineImage> {
 
   // Define the subject reference using the reference image.
    val controlReference = ImagenControlReference(
        image = referenceImage,
        referenceID = 1,
        controlType = CONTROL_TYPE_SCRIBBLE
    )

    val prompt = "A cat flying through outer space arranged like the scribble map[1]"

    val editedImage = model.editImage(
        references = listOf(controlReference),
        prompt = prompt,
        config = ImagenEditingConfig(
            editSteps = 50
        )
    )

    return editedImage
}

suspend fun customizeImageByStyle(model: ImagenModel, referenceVanGoghImage: Bitmap): ImagenGenerationResponse<ImagenInlineImage> {

    // Define the style reference using the reference image.
    val styleReference = ImagenStyleReference(
        image = referenceVanGoghImage,
        referenceID = 1,
        description = "Van Gogh style"
    )

    // Provide a prompt that describes the final image.
    // The "1" links the prompt to the style reference with ID 1.
    val prompt = "A cat flying through outer space, in the Van Gogh style[1]"

    // Use the editImage API to perform the style customization.
    val editedImage = model.editImage(
        references = listOf(styleReference),
        prompt = prompt,
        config = ImagenEditingConfig(
            editSteps = 50 // Number of editing steps, a higher value can improve quality
        )
    )

    return editedImage 
}