Image Generation - RunAnywhere Documentation

RunAnywhere.images generates an image from a prompt.

let result = try await RunAnywhere.images.generate(prompt: "A lighthouse at dusk")

Signatures

func generate(prompt: String, options: ImageOptions? = nil) async throws -> ImageResult
func generateStream(prompt: String, options: ImageOptions? = nil) async throws
    -> AsyncThrowingStream<ImageEvent, Error>

Options

let result = try await RunAnywhere.images.generate(
    prompt: "A lighthouse at dusk, oil painting",
    options: ImageOptions(
        negativePrompt: "blurry, text, watermark",
        width: 512,
        height: 512,
        steps: 20,
        guidanceScale: 7.5,
        seed: 42
    )
)

Field	Type	Default	Meaning
`negativePrompt`	`String?`	none	What to avoid
`width`	`Int?`	model default	Output width
`height`	`Int?`	model default	Output height
`steps`	`Int?`	model default	Denoising steps; more is slower and usually better
`guidanceScale`	`Float?`	model default	How closely to follow the prompt
`seed`	`Int?`	random	Fix it to reproduce an image
`mode`	`ImageMode`	`.generate`	`.generate` or inpainting
`reportPartials`	`Bool`	`false`	Emit intermediate images while streaming

Watching it appear

With reportPartials: true, the stream emits intermediate images so you can show progress rather than a spinner.

let stream = try await RunAnywhere.images.generateStream(
    prompt: "A lighthouse at dusk",
    options: ImageOptions(steps: 20, reportPartials: true)
)

for try await event in stream {
    switch event {
    case .partial(let image):
        preview = image
    case .completed(let result):
        final = result
    default:
        break
    }
}

Reproducing an image

Fix the seed and every other option, and the same prompt produces the same image.

ImageOptions(seed: 42)

Cost

Image generation is the heaviest thing in the SDK. A 512×512 image at 20 steps takes far longer than a text completion and warms the device noticeably. Show progress, allow cancellation by cancelling the enclosing Task, and do not run it on a timer.