license: mit
library_name: coreml
pipeline_tag: image-text-to-text
base_model: microsoft/Florence-2-base
base_model_relation: quantized
tags:
- coreml
- core-ml
- ios
- macos
- apple
- on-device
- vision-language
- captioning
- ocr
- grounding
- arxiv:2311.06242
Florence-2 — Core ML
Microsoft, 2024
Vision-language captioning, OCR, and VQA. Three-stage encoder-decoder. 768×768 input.

Core ML conversion of microsoft/Florence-2 for on-device inference on iPhone, iPad and Mac. Converted with coremltools; the packages are stateless, so all sequencing and buffering lives in your Swift code.
| Task | image text to text |
| Upstream | microsoft/Florence-2 |
| Packages | 3 |
| Download size | 229 MB |
| Minimum iOS | 17.0 |
| Peak RAM | ~1200 MB |
Files
| File | Size | Compute units | SHA-256 |
|---|---|---|---|
Florence2VisionEncoder.mlpackage.zip |
77 MB | cpuOnly |
9422f189c21220a0… |
Florence2TextEncoder.mlpackage.zip |
69 MB | cpuOnly |
f985deeef0408ea8… |
Florence2Decoder.mlpackage.zip |
81 MB | cpuOnly |
fe85a6faab528127… |
florence2_vocab.json |
976 KB | - |
861fee9af5520403… |
| Total | 229 MB |
compute_units is not a suggestion -- it is the configuration the conversion was verified against. Moving a package to a different compute unit can silently change the numerics (FP16 attention overflow) or crash on the GPU.
Download
hf download mlboydaisuke/coreml-zoo --include "florence2/*" --local-dir ./florence2
unzip './florence2/florence2/*.zip' -d ./florence2
Use in Swift
import CoreML
let config = MLModelConfiguration()
config.computeUnits = .cpuOnly // as converted — see the table above
// Unzip the .mlpackage, drop it into your Xcode target and Xcode compiles it
// at build time:
let model = try Florence2VisionEncoder(configuration: config)
// ...or compile a downloaded .mlpackage at runtime:
let compiled = try await MLModel.compileModel(at: mlpackageURL)
let model = try MLModel(contentsOf: compiled, configuration: config)
This model is split into 3 Core ML packages that are driven in sequence from Swift. Load them one at a time, copy the outputs out of the
MLMultiArraybuffers and release each model before loading the next — two large Core ML models resident at once will OOM on an iPhone.
Demo
- Sample app —
sample_apps/Florence2Demo, a standalone SwiftUI project. - Models Zoo — this model is downloadable and runnable inside the Models Zoo app on the App Store, no build required.
Conversion
- Script:
convert_florence2.py - Pitfalls hit during conversion (FP16 overflow, ANE buffer limits, stride handling):
docs/coreml_conversion_notes.md - Model index: CoreML-Models
License
The conversion inherits the upstream license: MIT.
Credits
- Upstream authors: microsoft/Florence-2, 2024
- Core ML conversion: john-rocky (Daisuke Majima)