Rust implementation of the DeepSeek-OCR inference stack with a fast CLI and an OpenAI-compatible HTTP server. The workspace packages the vision-language model, prompt tooling, and serving layer so you can build document understanding pipelines that run locally on CPU or Apple Metal.
ε¨ζΎδΈζζζ‘£? ηθΏι δΈζ.
- Vision preprocessing β
prepare_vision_input_from_imagebuilds a square global canvas with letterboxing (build_global_view) and, when crop mode is enabled, appliesdynamic_preprocesstiling to produce high-resolution local crops plus optional thumbnails. - SAM + CLIP fusion β each view is normalised via
image_to_tensor, pushed through the Candle ports of SAM (SamBackbone) and CLIP-L (ClipVisionModel), then flattened withbuild_clip_sam_tokensso the features stay spatially aligned. - Projector & layout tokens β the custom
ImageProjectorlinearly maps concatenated SAM/CLIP channels into the language hidden size while injecting learnedimage_newline/view_separatortokens to preserve grid structure, yielding the multimodal embeddings used during decoding. - Tokenizer alignment β
build_prompt_tokenssynthesises<image>spans whose length exactly matches the projected token count (global + local grids), ensuring OpenAI-style prompts remain consistent even after chat history pruning. - Decoder & caching β the text stack is a Candle reimplementation of DeepSeek-V2 (
DeepseekLanguageModel) with optional FlashAttention, rotary position embeddings, andDynamicCacheguards so both the CLI and server can stream tokens efficiently. - Observability & parity β debug builds expose CLIP/SAM traces (
VisionDebugFeatures) so we can diff intermediate tensors against the PyTorch reference; most stages are already numerically aligned, and the few remaining deltas (mainly projector normalisation + vision tiling) are tracked on the roadmap for upcoming releases.
The original DeepSeek-OCR ships as a Python + Transformers stackβpowerful, but hefty to deploy and awkward to embed. Rewriting the pipeline in Rust gives us:
- Smaller deployable artifacts with zero Python runtime or conda baggage.
- Memory-safe, thread-friendly infrastructure that blends into native Rust backends.
- Unified tooling (CLI + server) running on Candle + Rocket without the Python GIL overhead.
- Drop-in compatibility with OpenAI-style clients while tuned for single-turn OCR prompts.
- Candle for tensor compute, with Metal and CUDA backends and FlashAttention support.
- Rocket + async streaming for OpenAI-compatible
/v1/responsesand/v1/chat/completions. - tokenizers (Hugging Face) wrapped by
crates/assetsfor deterministic caching. - Pure Rust vision/prompt pipeline shared by CLI and server to avoid duplicated logic.
- Faster cold-start on Apple Silicon, lower RSS, and native binary distribution.
- Deterministic Hugging Face asset download + verification built into the workspace.
- Automatic single-turn chat compaction so OCR outputs stay stable even when clients send history.
- Ready-to-use OpenAI compatibility for tools like Open WebUI without adapters.
- One repo, two entrypoints β a batteries-included CLI for batch jobs and a Rocket-based server that speaks
/v1/responsesand/v1/chat/completions. - Works out of the box β pulls model weights, configs, and tokenizer from Hugging Face on first run.
- Optimised for Apple Silicon β optional Metal backend with FP16 execution for real-time OCR on laptops.
- OpenAI client compatibility β drop-in replacement for popular SDKs; the server automatically collapses chat history to the latest user turn for OCR-friendly prompts.
- Rust 1.78+ (edition 2024 support)
- Git
- Optional: Apple Silicon running macOS 13+ for Metal acceleration
- (Recommended) Hugging Face account with
HF_TOKENwhen pulling from thedeepseek-ai/DeepSeek-OCRrepo
git clone https://github.com/TimmyOVO/deepseek-ocr.rs.git
cd deepseek-ocr.rs
cargo fetchThe first invocation of the CLI or server downloads the config, tokenizer, and model-00001-of-000001.safetensors (~6.3GB) into DeepSeek-OCR/. To prefetch manually:
cargo run -p deepseek-ocr-cli -- --help # triggers asset downloadSet HF_HOME or HF_TOKEN if you store Hugging Face caches elsewhere. The full model package is ~6.3GB on disk and typically requires ~13GB of RAM headroom during inference (model + activations).
Build and run directly from the workspace:
cargo run -p deepseek-ocr-cli -- \
--prompt "<image>\n<|grounding|>Convert this receipt to markdown." \
--image baselines/sample/images/test.png \
--device cpu --max-new-tokens 512Install the CLI as a binary:
cargo install --path crates/cli
deepseek-ocr-cli --helpKey flags:
--prompt/--prompt-file: text with<image>slots--image: path(s) matching<image>placeholders--deviceand--dtype: choosemetal+f16on Apple Silicon--max-new-tokens: decoding budget
Launch an OpenAI-compatible endpoint:
cargo run -p deepseek-ocr-server -- \
--host 0.0.0.0 --port 8000 \
--device cpu --max-new-tokens 512Notes:
- Use
data:URLs or remotehttp(s)links; local paths are rejected. - The server collapses multi-turn chat inputs to the latest user message to keep prompts OCR-friendly.
- Works out of the box with tools such as Open WebUI or any OpenAI-compatible clientβjust point the base URL to your server (
http://localhost:8000/v1) and select thedeepseek-ocrmodel. - Adjust the request body limit with Rocket config if you routinely send large images.
- Available on macOS 13+ with Apple Silicon.
- Pass
--device metal --dtype f16to either CLI or server. - For best throughput, build the release profile:
cargo build --release -p deepseek-ocr-cli. - Combine with
--max-new-tokensand crop options to tune latency.
crates/coreβ shared inference pipeline, model loaders, conversation templates.crates/cliβ command-line frontend (deepseek-ocr-cli).crates/serverβ Rocket server exposing OpenAI-compatible endpoints.crates/assetsβ asset management (configuration, tokenizer, Hugging Face download helpers).baselines/β reference inputs and outputs for regression testing.
- Weights download fails β export
HF_TOKEN=<your-token>and retry. Assets land in~/.cache/huggingfaceby default. - Slow first response β model load and Metal warm-up happen on the initial request; later runs are faster.
- Large image rejection β increase Rocket JSON limits in
crates/server/src/main.rsor downscale the input.
- β Apple Metal backend with FP16 support and CLI/server parity on macOS.
- π Parity polish β finish projector normalisation + crop tiling alignment; extend intermediate-tensor diff suite beyond the current sample baseline.
- π Grounding & streaming β port the Python post-processing helpers (box extraction, markdown polish) and refine SSE streaming ergonomics.
- π Cross-platform acceleration β stabilise the Windows CUDA/FlashAttention prototype, bring up Vulkan/Metal auto-detection, and add opt-in GPU benchmarks.
- π Packaging & Ops β ship binary releases with deterministic asset checksums, richer logging/metrics, and Helm/docker references for server deploys.
- π Structured outputs β optional JSON schema tools for downstream automation once parity gaps close.
This repository inherits the licenses of its dependencies and the upstream DeepSeek-OCR model. Refer to DeepSeek-OCR/LICENSE for model terms and apply the same restrictions to downstream use.
