| --- |
| license: apache-2.0 |
| library_name: onnxruntime |
| pipeline_tag: image-to-text |
| tags: |
| - kaptchaocr |
| - captcha |
| - ocr |
| - onnx |
| - onnxruntime |
| - text-recognition |
| - pp-ocrv6 |
| --- |
| |
| <img src="assets/hero-banner.png" alt="KaptchaOCR" width="100%"> |
|
|
| # KaptchaOCR ft-tiny |
|
|
| One of the five fine-tuned **KaptchaOCR** models. This repository contains the |
| `tiny_rec.onnx` recognizer and its `tiny_rec.json` charset only. |
|
|
| KaptchaOCR is a Rust CAPTCHA library and server: |
| [github.com/ozalt/kaptchaocr](https://github.com/ozalt/kaptchaocr). |
|
|
| ## Model card |
|
|
| | Field | Value | |
| | --- | --- | |
| | Task | text recognition (CTC) | |
| | Base | PP-OCRv6 tiny | |
| | Profile | `fast` | |
| | Size | 4.3 MB | |
| | Input | RGB, height 48, dynamic width | |
| | Charset | 6,906 characters (`tiny_rec.json`) | |
| | Training data | 169,311 CAPTCHA images / 194,355 labels (oversampled), case-sensitive, 73 classes | |
| | Validation | 5,000 images | |
|
|
| The model is inference-only. KaptchaOCR handles preprocessing, CTC decoding |
| and the HTTP/server layer. |
|
|
| ## Benchmark |
|
|
| Held-out CAPTCHA sets, **4,399 images** total. Exact match is the whole string, |
| case-sensitive. Latency is mean ms/image on an Intel i5-1145G7, single process. |
|
|
| | Set | Exact | |
| | --- | ---: | |
| | archive1 | 52% | |
| | archive2 | 88% | |
| | archive3 | 95% | |
| | hammer888 | 42% | |
| | kaggle | 58% | |
| | lcsd | 94% | |
| | **Overall** | **67.0%** | |
|
|
| Character accuracy: **88.8%**. Mean latency: **9.8 ms**. |
|
|
| The test images are image-disjoint from training but come from the same public |
| sources, so this is not an out-of-distribution benchmark. Full tables, including |
| the comparison models (ddddocr and PP-OCRv6 base), are in the |
| [benchmark page](https://github.com/ozalt/kaptchaocr/blob/main/benchmarks/README.md). |
|
|
| ## Usage |
|
|
| Use the shipped manifest entry with the KaptchaOCR binary: |
|
|
| ```sh |
| kaptchaocr --ocr --manifest model/models.json --rec-model ft-tiny |
| ``` |
|
|
| For a non-inline build, point at this repo's files directly: |
|
|
| ```sh |
| kaptchaocr --ocr --ocr-path tiny_rec.onnx |
| ``` |
|
|
| The charset must sit next to the model with the same base name (`tiny_rec.onnx` → |
| `tiny_rec.json`). Manifest entry: |
|
|
| ```json |
| {"name": "ft-tiny", "task": "rec", "path": "tiny_rec.onnx", "charset": "tiny_rec.json"} |
| ``` |
|
|
| ## License |
|
|
| Apache-2.0. Fine-tuned from the PP-OCRv6 tiny model |
| ([PaddleOCR](https://github.com/PaddlePaddle/PaddleOCR), Apache-2.0). No |
| ddddocr weights are included in this repository. |
|
|
| ## Links |
|
|
| - [GitHub](https://github.com/ozalt/kaptchaocr) |
| - [All KaptchaOCR models](https://huggingface.co/collections/zaltahir/kaptchaocr) |
| - [Benchmarks](https://github.com/ozalt/kaptchaocr/blob/main/benchmarks/README.md) |
|
|
