## 1. Introduction to Seal Text Recognition Pipeline
Seal text recognition is a technology that automatically extracts and recognizes the content of seals from documents or images. The recognition of seal text is part of document processing and has many applications in various scenarios, such as contract comparison, warehouse entry and exit review, and invoice reimbursement review.
The seal text recognition pipeline is used to recognize the text content of seals, extracting the text information from seal images and outputting it in text form. This pipeline integrates the industry-renowned end-to-end OCR system PP-OCRv4, supporting the detection and recognition of curved seal text. Additionally, this pipeline integrates an optional layout region localization module, which can accurately locate the layout position of the seal within the entire document. It also includes optional document image orientation correction and distortion correction functions. Based on this pipeline, millisecond-level accurate text content prediction can be achieved on a CPU. This pipeline also provides flexible service deployment methods, supporting the use of multiple programming languages on various hardware. Moreover, it offers custom development capabilities, allowing you to train and fine-tune on your own dataset based on this pipeline, and the trained model can be seamlessly integrated.
<b>The seal text recognition</b> pipeline includes a seal text detection module and a text recognition module, as well as optional layout detection module, document image orientation classification module, and text image correction module.
- [Seal Text Detection Module](../module_usage/seal_text_detection.en.md)
<b>If you prioritize model accuracy, choose a model with higher accuracy. If you prioritize inference speed, choose a model with faster inference speed. If you prioritize model storage size, choose a model with smaller storage size.</b>
<p><b>Layout Region Detection Module (Optional):</b></p>
*<b>The layout detection model includes 20 common categories: document title, paragraph title, text, page number, abstract, table, references, footnotes, header, footer, algorithm, formula, formula number, image, table, seal, figure_table title, chart, and sidebar text and lists of references</b>
<table>
<thead>
<tr>
<th>Model</th><th>Model Download Link</th>
<th>mAP(0.5) (%)</th>
<th>GPU Inference Time (ms)<br/>[Normal Mode / High-Performance Mode]</th>
<th>CPU Inference Time (ms)<br/>[Normal Mode / High-Performance Mode]</th>
<td>A higher-precision layout area localization model trained on a self-built dataset containing Chinese and English papers, PPT, multi-layout magazines, contracts, books, exams, ancient books and research reports using RT-DETR-L</td>
<td>A high-precision layout area localization model trained on a self-built dataset containing Chinese and English papers, magazines, contracts, books, exams, and research reports using RT-DETR-L.</td>
<td>A layout area localization model with balanced precision and efficiency, trained on a self-built dataset containing Chinese and English papers, magazines, contracts, books, exams, and research reports using PicoDet-L.</td>
<td>A high-efficiency layout area localization model trained on a self-built dataset containing Chinese and English papers, magazines, contracts, books, exams, and research reports using PicoDet-S.</td>
</tr>
</tbody>
</table>
> ❗ The above list includes the <b>4 core models</b> that are key supported by the text recognition module. The module actually supports a total of <b>13 full models</b>. It includes multiple predefined models of different categories, among which there are 10 models specifically for the seal category. Apart from the three core models mentioned above, the remaining models are listed as follows:
<details><summary> 👉 Details of Model List</summary>
*<b>3-Class Layout Detection Model, including Table, Image, and Stamp</b>
<table>
<thead>
<tr>
<th>Model</th><th>Model Download Link</th>
<th>mAP(0.5) (%)</th>
<th>GPU Inference Time (ms)<br/>[Normal Mode / High-Performance Mode]</th>
<th>CPU Inference Time (ms)<br/>[Normal Mode / High-Performance Mode]</th>
<td>A high-efficiency layout area localization model trained on a self-built dataset of Chinese and English papers, magazines, and research reports using PicoDet-S.</td>
<td>A balanced efficiency and precision layout area localization model trained on a self-built dataset of Chinese and English papers, magazines, and research reports using PicoDet-L.</td>
<td>A high-precision layout area localization model trained on a self-built dataset of Chinese and English papers, magazines, and research reports using RT-DETR-H.</td>
</tr>
</tbody></table>
*<b>17-Class Area Detection Model, including 17 common layout categories: Paragraph Title, Image, Text, Number, Abstract, Content, Figure Caption, Formula, Table, Table Caption, References, Document Title, Footnote, Header, Algorithm, Footer, and Stamp</b>
<table>
<thead>
<tr>
<th>Model</th><th>Model Download Link</th>
<th>mAP(0.5) (%)</th>
<th>GPU Inference Time (ms)<br/>[Normal Mode / High-Performance Mode]</th>
<th>CPU Inference Time (ms)<br/>[Normal Mode / High-Performance Mode]</th>
<td>A high-efficiency layout area localization model trained on a self-built dataset of Chinese and English papers, magazines, and research reports using PicoDet-S.</td>
<td>A balanced efficiency and precision layout area localization model trained on a self-built dataset of Chinese and English papers, magazines, and research reports using PicoDet-L.</td>
<td>A high-precision layout area localization model trained on a self-built dataset of Chinese and English papers, magazines, and research reports using RT-DETR-H.</td>
<td>PP-OCRv4_server_rec_doc is trained on a mixed dataset of more Chinese document data and PP-OCR training data based on PP-OCRv4_server_rec. It has added the ability to recognize some traditional Chinese characters, Japanese, and special characters, and can support the recognition of more than 15,000 characters. In addition to improving the text recognition capability related to documents, it also enhances the general text recognition capability.</td>
The lightweight recognition model of PP-OCRv4 has high inference efficiency and can be deployed on various hardware devices, including edge devices.</td>
<td>The ultra-lightweight English recognition model, trained based on the PP-OCRv4 recognition model, supports the recognition of English letters and numbers.</td>
</tr>
</table>
> ❗ The above list features the <b>4 core models</b> that the text recognition module primarily supports. In total, this module supports <b>18 models</b>. The complete list of models is as follows:
<details><summary> 👉Model List Details</summary>
*<b>Chinese Recognition Model</b>
<table>
<tr>
<th>Model</th><th>Model Download Link</th>
<th>Recognition Avg Accuracy(%)</th>
<th>CPU Inference Time (ms)<br/>[Normal Mode / High-Performance Mode]</th>
<th>CPU Inference Time (ms)<br/>[Normal Mode / High-Performance Mode]</th>
<td>PP-OCRv4_server_rec_doc is trained on a mixed dataset of more Chinese document data and PP-OCR training data based on PP-OCRv4_server_rec. It has added the recognition capabilities for some traditional Chinese characters, Japanese, and special characters. The number of recognizable characters is over 15,000. In addition to the improvement in document-related text recognition, it also enhances the general text recognition capability.</td>
<td>The lightweight recognition model of PP-OCRv4 has high inference efficiency and can be deployed on various hardware devices, including edge devices.</td>
<td>PP-OCRv3’s lightweight recognition model is designed for high inference efficiency and can be deployed on a variety of hardware devices, including edge devices.</td>
</tr>
</table>
<table>
<tr>
<th>Model</th><th>Model Download Link</th>
<th>Recognition Avg Accuracy(%)</th>
<th>GPU Inference Time (ms)<br/>[Normal Mode / High-Performance Mode]</th>
<th>CPU Inference Time (ms)<br/>[Normal Mode / High-Performance Mode]</th>
SVTRv2 is a server text recognition model developed by the OpenOCR team of Fudan University's Visual and Learning Laboratory (FVL). It won the first prize in the PaddleOCR Algorithm Model Challenge - Task One: OCR End-to-End Recognition Task. The end-to-end recognition accuracy on the A list is 6% higher than that of PP-OCRv4.
</td>
</tr>
</table>
<table>
<tr>
<th>Model</th><th>Model Download Link</th>
<th>Recognition Avg Accuracy(%)</th>
<th>GPU Inference Time (ms)<br/>[Normal Mode / High-Performance Mode]</th>
<th>CPU Inference Time (ms)<br/>[Normal Mode / High-Performance Mode]</th>
<tdrowspan="1"> The RepSVTR text recognition model is a mobile text recognition model based on SVTRv2. It won the first prize in the PaddleOCR Algorithm Model Challenge - Task One: OCR End-to-End Recognition Task. The end-to-end recognition accuracy on the B list is 2.5% higher than that of PP-OCRv4, with the same inference speed.</td>
</tr>
</table>
*<b>English Recognition Model</b>
<table>
<tr>
<th>Model</th><th>Model Download Link</th>
<th>Recognition Avg Accuracy(%)</th>
<th>GPU Inference Time (ms)<br/>[Normal Mode / High-Performance Mode]</th>
<th>CPU Inference Time (ms)<br/>[Normal Mode / High-Performance Mode]</th>
<td>The ultra-lightweight English recognition model trained based on the PP-OCRv4 recognition model supports the recognition of English and numbers.</td>
<td>The ultra-lightweight English recognition model trained based on the PP-OCRv3 recognition model supports the recognition of English and numbers.</td>
</tr>
</table>
*<b>Multilingual Recognition Model</b>
<table>
<tr>
<th>Model</th><th>Model Download Link</th>
<th>Recognition Avg Accuracy(%)</th>
<th>GPU Inference Time (ms)<br/>[Normal Mode / High-Performance Mode]</th>
<th>CPU Inference Time (ms)<br/>[Normal Mode / High-Performance Mode]</th>
<td>The ultra-lightweight Korean recognition model trained based on the PP-OCRv3 recognition model supports the recognition of Korean and numbers. </td>
<td>The ultra-lightweight Japanese recognition model trained based on the PP-OCRv3 recognition model supports the recognition of Japanese and numbers.</td>
<td>The ultra-lightweight Traditional Chinese recognition model trained based on the PP-OCRv3 recognition model supports the recognition of Traditional Chinese and numbers.</td>
<td>The ultra-lightweight Telugu recognition model trained based on the PP-OCRv3 recognition model supports the recognition of Telugu and numbers.</td>
<td>The ultra-lightweight Kannada recognition model trained based on the PP-OCRv3 recognition model supports the recognition of Kannada and numbers.</td>
<td>The ultra-lightweight Latin recognition model trained based on the PP-OCRv3 recognition model supports the recognition of Latin script and numbers.</td>
<td>The ultra-lightweight Arabic script recognition model trained based on the PP-OCRv3 recognition model supports the recognition of Arabic script and numbers.</td>
The ultra-lightweight cyrillic alphabet recognition model trained based on the PP-OCRv3 recognition model supports the recognition of cyrillic letters and numbers.</td>
<td>The ultra-lightweight Devanagari script recognition model trained based on the PP-OCRv3 recognition model supports the recognition of Devanagari script and numbers.</td>
</tr>
</table>
</details>
<strong>Test Environment Description:</strong>
<ul>
<li><b>Performance Test Environment</b>
<ul>
<li><strong>Test Dataset：</strong>
<ul>
<li>Document Image Orientation Classification Module: A self-built dataset using PaddleX, covering multiple scenarios such as ID cards and documents, containing 1000 images.</li>
<li>Layout Detection Model: A self-built layout detection dataset using PaddleOCR, including 500 images of common document types such as Chinese and English papers, magazines, contracts, books, exam papers, and research reports.</li>
<li>3-Category Layout Detection Model: A self-built layout detection dataset using PaddleOCR, containing 1154 images of common document types such as Chinese and English papers, magazines, and research reports.</li>
<li>17-Category Region Detection Model: A self-built layout detection dataset using PaddleOCR, including 892 images of common document types such as Chinese and English papers, magazines, and research reports.</li>
<li>Text Detection Model: A self-built Chinese dataset using PaddleOCR, covering multiple scenarios such as street scenes, web images, documents, and handwriting, with 500 images for detection.</li>
<li> Chinese Recognition Model: A self-built Chinese dataset using PaddleOCR, covering multiple scenarios such as street scenes, web images, documents, and handwriting, with 11,000 images for text recognition.</li>
<li>ch_SVTRv2_rec: Evaluation set A for "OCR End-to-End Recognition Task" in the <ahref="https://aistudio.baidu.com/competition/detail/1131/0/introduction">PaddleOCR Algorithm Model Challenge</a></li>
<li>ch_RepSVTR_rec: Evaluation set B for "OCR End-to-End Recognition Task" in the <ahref="https://aistudio.baidu.com/competition/detail/1131/0/introduction">PaddleOCR Algorithm Model Challenge</a>.</li>
<li>English Recognition Model: A self-built English dataset using PaddleX.</li>
<li>Multilingual Recognition Model: A self-built multilingual dataset using PaddleX.</li>
<li>Text Line Orientation Classification Model: A self-built dataset using PaddleX, covering various scenarios such as ID cards and documents, containing 1000 images.</li>
<li>Seal Text Detection Model: A self-built dataset using PaddleX, containing 500 images of circular seal textures.</li>
Before using the seal text recognition production line locally, please ensure that you have completed the installation of the wheel package according to the [installation tutorial](../ppocr/installation.md). Once the installation is complete, you can experience it locally via the command line or integrate it with Python.
### 2.1 命令行方式体验
You can quickly experience the seal_recognition production line effect with a single command:
* The above command line is for quickly experiencing and viewing the effect. Generally, in a project, you often need to integrate through code. You can complete the quick inference of the pipeline with just a few lines of code. The inference code is as follows:
In the above Python script, the following steps were executed:
(1) The seal recognition pipeline object was instantiated via `create_pipeline()`, with the specific parameters described as follows:
<table>
<thead>
<tr>
<th>Parameter</th>
<th>Description</th>
<th>Type</th>
<th>Default Value</th>
</tr>
</thead>
<tbody>
<tr>
<td><code>pipeline</code></td>
<td>The name of the pipeline or the path to the pipeline configuration file. If it is a pipeline name, it must be supported by PaddleX.</td>
<td><code>str</code></td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>config</code></td>
<td>Specific configuration information for the pipeline (if set simultaneously with <code>pipeline</code>, it has higher priority than <code>pipeline</code>, and the pipeline name must be consistent with <code>pipeline</code>).</td>
<td><code>dict[str, Any]</code></td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>device</code></td>
<td>The device used for pipeline inference. It supports specifying the specific card number of the GPU, such as "gpu:0", other hardware card numbers, such as "npu:0", or CPU, such as "cpu". Supports specifying multiple devices simultaneously for parallel inference. For details, please refer to <ahref="../../instructions/parallel_inference.en.md#specifying-multiple-inference-devices">Pipeline Parallel Inference</a>.</td>
<td><code>str</code></td>
<td><code>gpu:0</code></td>
</tr>
<tr>
<td><code>use_hpip</code></td>
<td>Whether to enable the high-performance inference plugin. If set to <code>None</code>, the setting from the configuration file or <code>config</code> will be used.</td>
<td><code>bool</code></td>
<td>None</td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>hpi_config</code></td>
<td>High-performance inference configuration</td>
<td><code>dict</code> | <code>None</code></td>
<td>None</td>
<td><code>None</code></td>
</tr>
</tbody>
</table>
(2) Call the `predict()` method of the Seal Text Recognition pipeline object for inference prediction. This method will return a `generator`. Below are the parameters and their descriptions for the `predict()` method:
<table>
<thead>
<tr>
<th>Parameter</th>
<th>Description</th>
<th>Type</th>
<th>Options</th>
<th>Default Value</th>
</tr>
</thead>
<tr>
<td><code>input</code></td>
<td>Data to be predicted, supports multiple input types (required)</td>
<td><code>Python Var|str|list</code></td>
<td>
<ul>
<li><b>Python Var</b>: Image data represented by <code>numpy.ndarray</code></li>
<li><b>str</b>: Local path of an image or PDF file, e.g., <code>/root/data/img.jpg</code>; <b>URL link</b>, e.g., the network URL of an image or PDF file: <ahref="https://paddle-model-ecology.bj.bcebos.com/paddlex/imgs/demo_image/seal_text_det.png">Example</a>; <b>Local directory</b>, containing images to be predicted, e.g., <code>/root/data/</code> (currently does not support prediction of PDF files in directories; PDF files must be specified with an exact file path)</li>
<li><b>List</b>: Elements of the list must be of the above types, e.g., <code>[numpy.ndarray, numpy.ndarray]</code>, <code>[\"/root/data/img1.jpg\", \"/root/data/img2.jpg\"]</code>, <code>[\"/root/data1\", \"/root/data2\"]</code></li>
</ul>
</td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>device</code></td>
<td>Inference device for the pipeline</td>
<td><code>str|None</code></td>
<td>
<ul>
<li><b>CPU</b>: e.g., <code>cpu</code> for CPU inference;</li>
<li><b>GPU</b>: e.g., <code>gpu:0</code> for inference using the first GPU;</li>
<li><b>NPU</b>: e.g., <code>npu:0</code> for inference using the first NPU;</li>
<li><b>XPU</b>: e.g., <code>xpu:0</code> for inference using the first XPU;</li>
<li><b>MLU</b>: e.g., <code>mlu:0</code> for inference using the first MLU;</li>
<li><b>DCU</b>: e.g., <code>dcu:0</code> for inference using the first DCU;</li>
<li><b>None</b>: If set to <code>None</code>, the default value from the pipeline initialization will be used. During initialization, the local GPU device 0 will be prioritized; if unavailable, the CPU device will be used.</li>
<td>Whether to use the document orientation classification module</td>
<td><code>bool|None</code></td>
<td>
<ul>
<li><b>bool</b>: <code>True</code> or <code>False</code>;</li>
<li><b>None</b>: If set to <code>None</code>, the default value from the pipeline initialization will be used, initialized as <code>True</code>.</li>
</ul>
</td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>use_doc_unwarping</code></td>
<td>Whether to use the document unwarping module</td>
<td><code>bool|None</code></td>
<td>
<ul>
<li><b>bool</b>: <code>True</code> or <code>False</code>;</li>
<li><b>None</b>: If set to <code>None</code>, the default value from the pipeline initialization will be used, initialized as <code>True</code>.</li>
</ul>
</td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>use_layout_detection</code></td>
<td>Whether to use the layout detection module</td>
<td><code>bool|None</code></td>
<td>
<ul>
<li><b>bool</b>: <code>True</code> or <code>False</code>;</li>
<li><b>None</b>: If set to <code>None</code>, the default value from the pipeline initialization will be used, initialized as <code>True</code>.</li>
</ul>
</td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>layout_threshold</code></td>
<td>Confidence threshold for layout detection; only scores above this threshold will be output</td>
<td><code>float|dict|None</code></td>
<td>
<ul>
<li><b>float</b>: Any float greater than <code>0</code></li>
<li><b>dict</b>: Key is the int category ID, value is any float greater than <code>0</code></li>
<li><b>None</b>: If set to <code>None</code>, the default value from the pipeline initialization will be used, initialized as <code>0.5</code></li>
</ul>
</td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>layout_nms</code></td>
<td>Whether to use Non-Maximum Suppression (NMS) for layout detection post-processing</td>
<td><code>bool|None</code></td>
<td>
<ul>
<li><b>bool</b>: <code>True</code> or <code>False</code>;</li>
<li><b>None</b>: If set to <code>None</code>, the default value from the pipeline initialization will be used, initialized as <code>True</code>.</li>
</ul>
</td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>layout_unclip_ratio</code></td>
<td>Expansion ratio of detection box edges; if not specified, the default value from the PaddleX official model configuration will be used</td>
<td><code>float|list|None</code></td>
<td>
<ul>
<li><b>float</b>: Any float greater than 0, e.g., 1.1, which means expanding the width and height of the detection box by 1.1 times while keeping the center unchanged</li>
<li><b>list</b>: e.g., [1.2, 1.5], which means expanding the width of the detection box by 1.2 times and the height by 1.5 times while keeping the center unchanged</li>
<li><b>None</b>: If set to <code>None</code>, the default value from the pipeline initialization will be used, initialized as 1.0</li>
</ul>
</td>
</tr>
<tr>
<td><code>layout_merge_bboxes_mode</code></td>
<td>Merging mode for detection boxes in layout detection output; if not specified, the default value from the PaddleX official model configuration will be used</td>
<td><code>string|None</code></td>
<td>
<ul>
<li><b>large</b>: When set to <code>large</code>, only the largest external box will be retained for overlapping detection boxes, and the internal overlapping boxes will be removed.</li>
<li><b>small</b>: When set to <code>small</code>, only the smallest internal box will be retained for overlapping detection boxes, and the external overlapping boxes will be removed.</li>
<li><b>union</b>: No filtering of boxes will be performed; both internal and external boxes will be retained.</li>
<li><b>None</b>: If set to <code>None</code>, the default value from the pipeline initialization will be used, initialized as <code>large</code>.</li>
</ul>
</td>
<td>None</td>
</tr>
<tr>
<td><code>seal_det_limit_side_len</code></td>
<td>Side length limit for seal text detection</td>
<td><code>int|None</code></td>
<td>
<ul>
<li><b>int</b>: Any integer greater than <code>0</code></li>
<li><b>None</b>: If set to <code>None</code>, the default value from the pipeline initialization will be used, initialized as <code>736</code></li>
</ul>
</td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>seal_rec_score_thresh</code></td>
<td>Text recognition threshold; text results with scores above this threshold will be retained</td>
<td><code>float|None</code></td>
<td>
<ul>
<li><b>float</b>: Any float greater than <code>0</code></li>
<li><b>None</b>: If set to <code>None</code>, the default value from the pipeline initialization will be used, initialized as <code>0.0</code>. This means no threshold is applied.</li>
</ul>
</td>
<td><code>None</code></td>
</tr>
</table>
(3) Process the prediction results. The prediction result for each sample is of `dict` type and supports operations such as printing, saving as an image, and saving as a `json` file:
<table>
<thead>
<tr>
<th>Method</th>
<th>Description</th>
<th>Parameter</th>
<th>Parameter Type</th>
<th>Parameter Description</th>
<th>Default Value</th>
</tr>
</thead>
<tr>
<tdrowspan="3"><code>print()</code></td>
<tdrowspan="3">Print results to the terminal</td>
<td><code>format_json</code></td>
<td><code>bool</code></td>
<td>Whether to format the output content using <code>JSON</code> indentation</td>
<td><code>True</code></td>
</tr>
<tr>
<td><code>indent</code></td>
<td><code>int</code></td>
<td>Specify the indentation level to beautify the output <code>JSON</code> data for better readability, effective only when <code>format_json</code> is <code>True</code></td>
<td>4</td>
</tr>
<tr>
<td><code>ensure_ascii</code></td>
<td><code>bool</code></td>
<td>Control whether to escape non-<code>ASCII</code> characters to <code>Unicode</code>. When set to <code>True</code>, all non-<code>ASCII</code> characters will be escaped; <code>False</code> will retain the original characters, effective only when <code>format_json</code> is <code>True</code></td>
<td><code>False</code></td>
</tr>
<tr>
<tdrowspan="3"><code>save_to_json()</code></td>
<tdrowspan="3">Save results as a json file</td>
<td><code>save_path</code></td>
<td><code>str</code></td>
<td>The file path to save the results. When it is a directory, the saved file name will be consistent with the input file type</td>
<td>None</td>
</tr>
<tr>
<td><code>indent</code></td>
<td><code>int</code></td>
<td>Specify the indentation level to beautify the output <code>JSON</code> data for better readability, effective only when <code>format_json</code> is <code>True</code></td>
<td>4</td>
</tr>
<tr>
<td><code>ensure_ascii</code></td>
<td><code>bool</code></td>
<td>Control whether to escape non-<code>ASCII</code> characters to <code>Unicode</code>. When set to <code>True</code>, all non-<code>ASCII</code> characters will be escaped; <code>False</code> will retain the original characters, effective only when <code>format_json</code> is <code>True</code></td>
<td><code>False</code></td>
</tr>
<tr>
<td><code>save_to_img()</code></td>
<td>Save results as an image file</td>
<td><code>save_path</code></td>
<td><code>str</code></td>
<td>The file path to save the results, supports directory or file path</td>
<td>None</td>
</tr>
</table>
- Calling the `print()` method will print the results to the terminal, and the explanations of the printed content are as follows:
-`input_path`: `(str)` The input path of the image to be predicted.
-`model_settings`: `(Dict[str, bool])` The model parameters required for pipeline configuration.
-`use_doc_preprocessor`: `(bool)` Controls whether to enable the document preprocessing sub-pipeline.
-`use_layout_detection`: `(bool)` Controls whether to enable the layout detection sub-module.
-`layout_det_res`: `(Dict[str, Union[List[numpy.ndarray], List[float]]])` The output result of the layout detection sub-module. Only exists when `use_layout_detection=True`.
-`input_path`: `(Union[str, None])` The image path accepted by the layout detection module. Saved as `None` when the input is a `numpy.ndarray`.
-`page_index`: `(Union[int, None])` Indicates the current page number of the PDF if the input is a PDF file; otherwise, it is `None`.
-`boxes`: `(List[Dict])` A list of detected layout seal regions, with each element containing the following fields:
-`cls_id`: `(int)` The class ID of the detected seal region.
-`score`: `(float)` The confidence score of the detected region.
-`coordinate`: `(List[float])` The coordinates of the four corners of the detection box, in the order of x1, y1, x2, y2, representing the x-coordinate of the top-left corner, the y-coordinate of the top-left corner, the x-coordinate of the bottom-right corner, and the y-coordinate of the bottom-right corner.
-`seal_res_list`: `List[Dict]` A list of seal text recognition results, with each element containing the following fields:
-`input_path`: `(Union[str, None])` The image path accepted by the seal text recognition pipeline. Saved as `None` when the input is a `numpy.ndarray`.
-`page_index`: `(Union[int, None])` Indicates the current page number of the PDF if the input is a PDF file; otherwise, it is `None`.
-`model_settings`: `(Dict[str, bool])` The model configuration parameters for the seal text recognition pipeline.
-`use_doc_preprocessor`: `(bool)` Controls whether to enable the document preprocessing sub-pipeline.
-`use_textline_orientation`: `(bool)` Controls whether to enable the text line orientation classification sub-module.
-`doc_preprocessor_res`: `(Dict[str, Union[str, Dict[str, bool], int]])` The output result of the document preprocessing sub-pipeline. Only exists when `use_doc_preprocessor=True`.
-`input_path`: `(Union[str, None])` The image path accepted by the document preprocessing sub-pipeline. Saved as `None` when the input is a `numpy.ndarray`.
-`model_settings`: `(Dict)` The model configuration parameters for the preprocessing sub-pipeline.
-`use_doc_orientation_classify`: `(bool)` Controls whether to enable document orientation classification.
-`use_doc_unwarping`: `(bool)` Controls whether to enable document unwarping.
-`angle`: `(int)` The predicted result of document orientation classification. When enabled, it takes values [0, 1, 2, 3], corresponding to [0°, 90°, 180°, 270°]; when disabled, it is -1.
-`dt_polys`: `(List[numpy.ndarray])` A list of polygon boxes for seal text detection. Each detection box is represented by a numpy array of multiple vertex coordinates, with the array shape being (n, 2).
-`dt_scores`: `(List[float])` A list of confidence scores for text detection boxes.
-`text_det_params`: `(Dict[str, Dict[str, int, float]])` Configuration parameters for the text detection module.
-`limit_side_len`: `(int)` The side length limit value during image preprocessing.
-`limit_type`: `(str)` The handling method for side length limits.
-`thresh`: `(float)` The confidence threshold for text pixel classification.
-`box_thresh`: `(float)` The confidence threshold for text detection boxes.
-`unclip_ratio`: `(float)` The expansion ratio for text detection boxes.
-`text_type`: `(str)` The type of seal text detection, currently fixed as "seal".
-`text_rec_score_thresh`: `(float)` The filtering threshold for text recognition results.
-`rec_texts`: `(List[str])` A list of text recognition results, containing only texts with confidence scores above `text_rec_score_thresh`.
-`rec_scores`: `(List[float])` A list of confidence scores for text recognition, filtered by `text_rec_score_thresh`.
-`rec_polys`: `(List[numpy.ndarray])` A list of text detection boxes filtered by confidence score, in the same format as `dt_polys`.
-`rec_boxes`: `(numpy.ndarray)` An array of rectangular bounding boxes for detection boxes; the seal recognition pipeline returns an empty array.
- Calling the `save_to_json()` method will save the above content to the specified `save_path`. If a directory is specified, the saved path will be `save_path/{your_img_basename}_res.json`. If a file is specified, it will be saved directly to that file. Since JSON files do not support saving numpy arrays, `numpy.array` types will be converted to list format.
- Calling the `save_to_img()` method will save the visualization results to the specified `save_path`. If a directory is specified, the saved path will be `save_path/{your_img_basename}_seal_res_region1.{your_img_extension}`. If a file is specified, it will be saved directly to that file. (The pipeline usually contains multiple result images, so it is not recommended to specify a specific file path directly, as multiple images will be overwritten, and only the last image will be retained.)
* Additionally, you can obtain visualized images with results and prediction results through attributes, as follows:
<table>
<thead>
<tr>
<th>Attribute</th>
<th>Description</th>
</tr>
</thead>
<tr>
<tdrowspan="1"><code>json</code></td>
<tdrowspan="1">Get the prediction results in <code>json</code> format.</td>
</tr>
<tr>
<tdrowspan="2"><code>img</code></td>
<tdrowspan="2">Get the visualization results in <code>dict</code> format.</td>
</tr>
</table>
- The prediction results obtained through the `json` attribute are of dict type, with content consistent with what is saved by calling the `save_to_json()` method.
- The prediction results returned by the `img` attribute are of dict type. The keys are `layout_det_res`, `seal_res_region1`, and `preprocessed_img`, corresponding to three `Image.Image` objects: one for visualizing layout detection, one for visualizing seal text recognition results, and one for visualizing image preprocessing. If the image preprocessing sub-module is not used, `preprocessed_img` will not be included in the dictionary. If the layout region detection module is not used, `layout_det_res` will not be included.
Additionally, you can obtain the configuration file for the seal text recognition pipeline and load the configuration file for prediction. You can execute the following command to save the results in `my_path`:
If you have obtained the configuration file, you can customize the settings for the seal text recognition pipeline by simply modifying the `pipeline` parameter value in the `create_pipeline` method to the path of the pipeline configuration file. The example is as follows:
<td>Whether to load the document orientation classification module. If set to <code>None</code>, the default value initialized by the production line will be used, initialized to <code>True</code>.</td>
<td><code>bool</code></td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>use_doc_unwarping</code></td>
<td>Whether to load the text image correction module. If set to <code>None</code>, the default value initialized by the production line will be used, initialized to <code>True</code>.</td>
<td><code>bool</code></td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>use_layout_detection</code></td>
<td>Whether to load the layout detection module. If set to <code>None</code>, the default value initialized by the production line will be used, initialized to <code>True</code>.</td>
<td><code>bool</code></td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>layout_threshold</code></td>
<td>Layout detection confidence threshold; only scores greater than this threshold will be output.
<ul>
<li><b>float</b>: Any floating point number greater than <code>0</code></li>
<li><b>dict</b>: Keys are int category IDs, values are any floating point number greater than <code>0</code></li>
<li><b>None</b>: If set to <code>None</code>, the default value initialized by the production line, <code>0.5</code>, will be used</li>
</ul>
</td>
<td><code>float|dict</code></td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>layout_nms</code></td>
<td>Whether to use post-processing NMS in layout detection. If set to <code>None</code>, the default value initialized by the production line, initialized to <code>True</code>, will be used.</td>
<td><code>bool</code></td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>layout_unclip_ratio</code></td>
<td>Scale factor for the sides of the detection box.
<ul>
<li><b>float</b>: A floating point number greater than 0, e.g., 1.1, indicates that the width and height of the detection box output by the model will be expanded by 1.1 times, keeping the center unchanged</li>
<li><b>list</b>: e.g., [1.2, 1.5], indicates that the width will be expanded by 1.2 times and the height by 1.5 times, keeping the center unchanged</li>
<li><b>None</b>: If set to <code>None</code>, the default value initialized by the production line, initialized to 1.0, will be used</li>
</ul>
</td>
<td><code>float|list</code></td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>layout_merge_bboxes_mode</code></td>
<td>Mode for merging detection boxes output by the model in layout detection.
<ul>
<li><b>large</b>: When set to large, only the largest external box will be retained for overlapping detection boxes, and overlapping internal boxes will be deleted</li>
<li><b>small</b>: When set to small, only the small internal box will be retained, and overlapping external boxes will be deleted</li>
<li><b>union</b>: No filtering will be performed, and both internal and external boxes will be retained</li>
<li><b>None</b>: If set to <code>None</code>, the default value initialized by the production line, initialized to <code>large</code>, will be used</li>
</ul>
</td>
<td><code>str</code></td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>seal_det_limit_side_len</code></td>
<td>Image side length limit for seal text detection.
<ul>
<li><b>int</b>: Any integer greater than <code>0</code></li>
<li><b>None</b>: If set to <code>None</code>, the default value initialized by the production line, initialized to <code>736</code>, will be used</li>
</ul>
</td>
<td><code>int</code></td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>seal_det_limit_type</code></td>
<td>Image side length limit type for seal text detection.
<ul>
<li><b>str</b>: Supports <code>min</code> and <code>max</code>; <code>min</code> ensures that the shortest side of the image is not less than <code>det_limit_side_len</code>, while <code>max</code> ensures that the longest side of the image is not greater than <code>limit_side_len</code></li>
<li><b>None</b>: If set to <code>None</code>, the default value initialized by the production line, initialized to <code>min</code>, will be used</li>
</ul>
</td>
<td><code>str</code></td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>seal_det_thresh</code></td>
<td>Detection pixel threshold; only pixels with scores greater than this threshold in the output probability map will be considered as text pixels.
<ul>
<li><b>float</b>: Any floating point number greater than <code>0</code></li>
<li><b>None</b>: If set to <code>None</code>, the default value initialized by the production line, <code>0.2</code>, will be used</li>
</ul>
</td>
<td><code>float</code></td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>seal_det_box_thresh</code></td>
<td>Detection box threshold; when the average score of all pixels within a detection result box is greater than this threshold, the result is considered a text area.
<ul>
<li><b>float</b>: Any floating point number greater than <code>0</code></li>
<li><b>None</b>: If set to <code>None</code>, the default value initialized by the production line, <code>0.6</code>, will be used</li>
</ul>
</td>
<td><code>float</code></td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>seal_det_unclip_ratio</code></td>
<td>Seal text detection expansion coefficient; the larger the value, the greater the expansion area.
<ul>
<li><b>float</b>: Any floating point number greater than <code>0</code></li>
<li><b>None</b>: If set to <code>None</code>, the default value initialized by the production line, <code>0.5</code>, will be used</li>
</ul>
</td>
<td><code>float</code></td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>seal_rec_score_thresh</code></td>
<td>Text recognition threshold; text results with scores greater than this threshold will be retained.
<ul>
<li><b>float</b>: Any floating point number greater than <code>0</code></li>
<li><b>None</b>: If set to <code>None</code>, the default value initialized by the production line, <code>0.0</code>, will be used, meaning no threshold is set</li>
</ul>
</td>
<td><code>float</code></td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>device</code></td>
<td>The device used for inference. Supports specifying a specific card number.
<ul>
<li><b>CPU</b>: e.g., <code>cpu</code> indicates using the CPU for inference</li>
<li><b>GPU</b>: e.g., <code>gpu:0</code> indicates using the first GPU for inference</li>
<li><b>NPU</b>: e.g., <code>npu:0</code> indicates using the first NPU for inference</li>
<li><b>XPU</b>: e.g., <code>xpu:0</code> indicates using the first XPU for inference</li>
<li><b>MLU</b>: e.g., <code>mlu:0</code> indicates using the first MLU for inference</li>
<li><b>DCU</b>: e.g., <code>dcu:0</code> indicates using the first DCU for inference</li>
<li><b>None</b>: If set to <code>None</code>, the default value initialized by the production line will be used, which will prioritize using local GPU 0 if available, otherwise it will use the CPU</li>
</ul>
</td>
<td><code>str</code></td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>enable_hpi</code></td>
<td>Whether to enable high-performance inference.</td>
<td><code>bool</code></td>
<td><code>False</code></td>
</tr>
<tr>
<td><code>use_tensorrt</code></td>
<td>Whether to use TensorRT for inference acceleration.</td>
<td><code>bool</code></td>
<td><code>False</code></td>
</tr>
<tr>
<td><code>min_subgraph_size</code></td>
<td>Minimum subgraph size, used for optimizing model subgraph computation.</td>
<td><code>int</code></td>
<td><code>3</code></td>
</tr>
<tr>
<td><code>precision</code></td>
<td>Computation precision, such as fp32 or fp16.</td>
<td><code>str</code></td>
<td><code>fp32</code></td>
</tr>
<tr>
<td><code>enable_mkldnn</code></td>
<td>Whether to enable the MKL-DNN acceleration library. If set to <code>None</code>, it will be enabled by default.</td>
<td><code>bool</code></td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>cpu_threads</code></td>
<td>The number of threads to use when performing inference on the CPU.</td>
<td><code>int</code></td>
<td><code>8</code></td>
</tr>
</tbody>
</table>
(2) Call the `predict()` method of the seal text recognition production object for inference prediction. This method will return a list of results.
Additionally, the production line also offers the `predict_iter()` method. Both methods are identical in terms of parameter acceptance and result return; the difference lies in that `predict_iter()` returns a `generator`, allowing for gradual processing and retrieval of prediction results. This is suitable for handling large datasets or scenarios where memory saving is desired. You can choose either method based on your actual needs.
Below are the parameters for the `predict()` method and their descriptions:
<table>
<thead>
<tr>
<th>Parameter</th>
<th>Description</th>
<th>Type</th>
<th>Options</th>
<th>Default Value</th>
</tr>
</thead>
<tr>
<td><code>input</code></td>
<td>Data to be predicted, supports multiple input types (required)</td>
<td><code>Python Var|str|list</code></td>
<td>
<ul>
<li><b>Python Var</b>: Image data represented by <code>numpy.ndarray</code></li>
<li><b>str</b>: Local path of an image or PDF file, e.g., <code>/root/data/img.jpg</code>; <b>URL link</b>, e.g., the network URL of an image or PDF file: <ahref="https://paddle-model-ecology.bj.bcebos.com/paddlex/imgs/demo_image/seal_text_det.png">Example</a>; <b>Local directory</b>, containing images to be predicted, e.g., <code>/root/data/</code> (currently does not support prediction of PDF files in directories; PDF files must be specified with an exact file path)</li>
<li><b>List</b>: Elements of the list must be of the above types, e.g., <code>[numpy.ndarray, numpy.ndarray]</code>, <code>[\"/root/data/img1.jpg\", \"/root/data/img2.jpg\"]</code>, <code>[\"/root/data1\", \"/root/data2\"]</code></li>
</ul>
</td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>device</code></td>
<td>Inference device for the pipeline</td>
<td><code>str|None</code></td>
<td>
<ul>
<li><b>CPU</b>: e.g., <code>cpu</code> for CPU inference;</li>
<li><b>GPU</b>: e.g., <code>gpu:0</code> for inference using the first GPU;</li>
<li><b>NPU</b>: e.g., <code>npu:0</code> for inference using the first NPU;</li>
<li><b>XPU</b>: e.g., <code>xpu:0</code> for inference using the first XPU;</li>
<li><b>MLU</b>: e.g., <code>mlu:0</code> for inference using the first MLU;</li>
<li><b>DCU</b>: e.g., <code>dcu:0</code> for inference using the first DCU;</li>
<li><b>None</b>: If set to <code>None</code>, the default value from the pipeline initialization will be used. During initialization, the local GPU device 0 will be prioritized; if unavailable, the CPU device will be used.</li>
<td>Whether to use the document orientation classification module</td>
<td><code>bool|None</code></td>
<td>
<ul>
<li><b>bool</b>: <code>True</code> or <code>False</code>;</li>
<li><b>None</b>: If set to <code>None</code>, the default value from the pipeline initialization will be used, initialized as <code>True</code>.</li>
</ul>
</td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>use_doc_unwarping</code></td>
<td>Whether to use the document unwarping module</td>
<td><code>bool|None</code></td>
<td>
<ul>
<li><b>bool</b>: <code>True</code> or <code>False</code>;</li>
<li><b>None</b>: If set to <code>None</code>, the default value from the pipeline initialization will be used, initialized as <code>True</code>.</li>
</ul>
</td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>use_layout_detection</code></td>
<td>Whether to use the layout detection module</td>
<td><code>bool|None</code></td>
<td>
<ul>
<li><b>bool</b>: <code>True</code> or <code>False</code>;</li>
<li><b>None</b>: If set to <code>None</code>, the default value from the pipeline initialization will be used, initialized as <code>True</code>.</li>
</ul>
</td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>layout_threshold</code></td>
<td>Confidence threshold for layout detection; only scores above this threshold will be output</td>
<td><code>float|dict|None</code></td>
<td>
<ul>
<li><b>float</b>: Any float greater than <code>0</code></li>
<li><b>dict</b>: Key is the int category ID, value is any float greater than <code>0</code></li>
<li><b>None</b>: If set to <code>None</code>, the default value from the pipeline initialization will be used, initialized as <code>0.5</code></li>
</ul>
</td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>layout_nms</code></td>
<td>Whether to use Non-Maximum Suppression (NMS) for layout detection post-processing</td>
<td><code>bool|None</code></td>
<td>
<ul>
<li><b>bool</b>: <code>True</code> or <code>False</code>;</li>
<li><b>None</b>: If set to <code>None</code>, the default value from the pipeline initialization will be used, initialized as <code>True</code>.</li>
</ul>
</td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>layout_unclip_ratio</code></td>
<td>Expansion ratio of detection box edges; if not specified, the default value from the PaddleX official model configuration will be used</td>
<td><code>float|list|None</code></td>
<td>
<ul>
<li><b>float</b>: Any float greater than 0, e.g., 1.1, which means expanding the width and height of the detection box by 1.1 times while keeping the center unchanged</li>
<li><b>list</b>: e.g., [1.2, 1.5], which means expanding the width of the detection box by 1.2 times and the height by 1.5 times while keeping the center unchanged</li>
<li><b>None</b>: If set to <code>None</code>, the default value from the pipeline initialization will be used, initialized as 1.0</li>
</ul>
</td>
</tr>
<tr>
<td><code>layout_merge_bboxes_mode</code></td>
<td>Merging mode for detection boxes in layout detection output; if not specified, the default value from the PaddleX official model configuration will be used</td>
<td><code>string|None</code></td>
<td>
<ul>
<li><b>large</b>: When set to <code>large</code>, only the largest external box will be retained for overlapping detection boxes, and the internal overlapping boxes will be removed.</li>
<li><b>small</b>: When set to <code>small</code>, only the smallest internal box will be retained for overlapping detection boxes, and the external overlapping boxes will be removed.</li>
<li><b>union</b>: No filtering of boxes will be performed; both internal and external boxes will be retained.</li>
<li><b>None</b>: If set to <code>None</code>, the default value from the pipeline initialization will be used, initialized as <code>large</code>.</li>
</ul>
</td>
<td>None</td>
</tr>
<tr>
<td><code>seal_det_limit_side_len</code></td>
<td>Side length limit for seal text detection</td>
<td><code>int|None</code></td>
<td>
<ul>
<li><b>int</b>: Any integer greater than <code>0</code></li>
<li><b>None</b>: If set to <code>None</code>, the default value from the pipeline initialization will be used, initialized as <code>736</code></li>
</ul>
</td>
<td><code>None</code></td>
</tr>
<tr>
<td><code>seal_rec_score_thresh</code></td>
<td>Text recognition threshold; text results with scores above this threshold will be retained</td>
<td><code>float|None</code></td>
<td>
<ul>
<li><b>float</b>: Any float greater than <code>0</code></li>
<li><b>None</b>: If set to <code>None</code>, the default value from the pipeline initialization will be used, initialized as <code>0.0</code>. This means no threshold is applied.</li>
</ul>
</td>
<td><code>None</code></td>
</tr>
</table>
(3) Process the prediction results. The prediction result for each sample is of `dict` type and supports operations such as printing, saving as an image, and saving as a `json` file:
<table>
<thead>
<tr>
<th>Method</th>
<th>Description</th>
<th>Parameter</th>
<th>Parameter Type</th>
<th>Parameter Description</th>
<th>Default Value</th>
</tr>
</thead>
<tr>
<tdrowspan="3"><code>print()</code></td>
<tdrowspan="3">Print results to the terminal</td>
<td><code>format_json</code></td>
<td><code>bool</code></td>
<td>Whether to format the output content using <code>JSON</code> indentation</td>
<td><code>True</code></td>
</tr>
<tr>
<td><code>indent</code></td>
<td><code>int</code></td>
<td>Specify the indentation level to beautify the output <code>JSON</code> data for better readability, effective only when <code>format_json</code> is <code>True</code></td>
<td>4</td>
</tr>
<tr>
<td><code>ensure_ascii</code></td>
<td><code>bool</code></td>
<td>Control whether to escape non-<code>ASCII</code> characters to <code>Unicode</code>. When set to <code>True</code>, all non-<code>ASCII</code> characters will be escaped; <code>False</code> will retain the original characters, effective only when <code>format_json</code> is <code>True</code></td>
<td><code>False</code></td>
</tr>
<tr>
<tdrowspan="3"><code>save_to_json()</code></td>
<tdrowspan="3">Save results as a json file</td>
<td><code>save_path</code></td>
<td><code>str</code></td>
<td>The file path to save the results. When it is a directory, the saved file name will be consistent with the input file type</td>
<td>None</td>
</tr>
<tr>
<td><code>indent</code></td>
<td><code>int</code></td>
<td>Specify the indentation level to beautify the output <code>JSON</code> data for better readability, effective only when <code>format_json</code> is <code>True</code></td>
<td>4</td>
</tr>
<tr>
<td><code>ensure_ascii</code></td>
<td><code>bool</code></td>
<td>Control whether to escape non-<code>ASCII</code> characters to <code>Unicode</code>. When set to <code>True</code>, all non-<code>ASCII</code> characters will be escaped; <code>False</code> will retain the original characters, effective only when <code>format_json</code> is <code>True</code></td>
<td><code>False</code></td>
</tr>
<tr>
<td><code>save_to_img()</code></td>
<td>Save results as an image file</td>
<td><code>save_path</code></td>
<td><code>str</code></td>
<td>The file path to save the results, supports directory or file path</td>
<td>None</td>
</tr>
</table>
<b>Note:</b> The parameters in the configuration file are the pipeline initialization parameters. If you wish to change the initialization parameters of the seal text recognition pipeline, you can directly modify the parameters in the configuration file and load the configuration file for prediction. Additionally, CLI prediction also supports passing in a configuration file. Simply specify the path of the configuration file with `--pipeline`.
- Calling the `print()` method will print the results to the terminal, and the explanations of the printed content are as follows:
-`input_path`: `(str)` The input path of the image to be predicted.
-`model_settings`: `(Dict[str, bool])` The model parameters required for pipeline configuration.
-`use_doc_preprocessor`: `(bool)` Controls whether to enable the document preprocessing sub-pipeline.
-`use_layout_detection`: `(bool)` Controls whether to enable the layout detection sub-module.
-`layout_det_res`: `(Dict[str, Union[List[numpy.ndarray], List[float]]])` The output result of the layout detection sub-module. Only exists when `use_layout_detection=True`.
-`input_path`: `(Union[str, None])` The image path accepted by the layout detection module. Saved as `None` when the input is a `numpy.ndarray`.
-`page_index`: `(Union[int, None])` Indicates the current page number of the PDF if the input is a PDF file; otherwise, it is `None`.
-`boxes`: `(List[Dict])` A list of detected layout seal regions, with each element containing the following fields:
-`cls_id`: `(int)` The class ID of the detected seal region.
-`score`: `(float)` The confidence score of the detected region.
-`coordinate`: `(List[float])` The coordinates of the four corners of the detection box, in the order of x1, y1, x2, y2, representing the x-coordinate of the top-left corner, the y-coordinate of the top-left corner, the x-coordinate of the bottom-right corner, and the y-coordinate of the bottom-right corner.
-`seal_res_list`: `List[Dict]` A list of seal text recognition results, with each element containing the following fields:
-`input_path`: `(Union[str, None])` The image path accepted by the seal text recognition pipeline. Saved as `None` when the input is a `numpy.ndarray`.
-`page_index`: `(Union[int, None])` Indicates the current page number of the PDF if the input is a PDF file; otherwise, it is `None`.
-`model_settings`: `(Dict[str, bool])` The model configuration parameters for the seal text recognition pipeline.
-`use_doc_preprocessor`: `(bool)` Controls whether to enable the document preprocessing sub-pipeline.
-`use_textline_orientation`: `(bool)` Controls whether to enable the text line orientation classification sub-module.
-`doc_preprocessor_res`: `(Dict[str, Union[str, Dict[str, bool], int]])` The output result of the document preprocessing sub-pipeline. Only exists when `use_doc_preprocessor=True`.
-`input_path`: `(Union[str, None])` The image path accepted by the document preprocessing sub-pipeline. Saved as `None` when the input is a `numpy.ndarray`.
-`model_settings`: `(Dict)` The model configuration parameters for the preprocessing sub-pipeline.
-`use_doc_orientation_classify`: `(bool)` Controls whether to enable document orientation classification.
-`use_doc_unwarping`: `(bool)` Controls whether to enable document unwarping.
-`angle`: `(int)` The predicted result of document orientation classification. When enabled, it takes values [0, 1, 2, 3], corresponding to [0°, 90°, 180°, 270°]; when disabled, it is -1.
-`dt_polys`: `(List[numpy.ndarray])` A list of polygon boxes for seal text detection. Each detection box is represented by a numpy array of multiple vertex coordinates, with the array shape being (n, 2).
-`dt_scores`: `(List[float])` A list of confidence scores for text detection boxes.
-`text_det_params`: `(Dict[str, Dict[str, int, float]])` Configuration parameters for the text detection module.
-`limit_side_len`: `(int)` The side length limit value during image preprocessing.
-`limit_type`: `(str)` The handling method for side length limits.
-`thresh`: `(float)` The confidence threshold for text pixel classification.
-`box_thresh`: `(float)` The confidence threshold for text detection boxes.
-`unclip_ratio`: `(float)` The expansion ratio for text detection boxes.
-`text_type`: `(str)` The type of seal text detection, currently fixed as "seal".
-`text_rec_score_thresh`: `(float)` The filtering threshold for text recognition results.
-`rec_texts`: `(List[str])` A list of text recognition results, containing only texts with confidence scores above `text_rec_score_thresh`.
-`rec_scores`: `(List[float])` A list of confidence scores for text recognition, filtered by `text_rec_score_thresh`.
-`rec_polys`: `(List[numpy.ndarray])` A list of text detection boxes filtered by confidence score, in the same format as `dt_polys`.
-`rec_boxes`: `(numpy.ndarray)` An array of rectangular bounding boxes for detection boxes; the seal recognition pipeline returns an empty array.
- Calling the `save_to_json()` method will save the above content to the specified `save_path`. If a directory is specified, the saved path will be `save_path/{your_img_basename}_res.json`. If a file is specified, it will be saved directly to that file. Since JSON files do not support saving numpy arrays, `numpy.array` types will be converted to list format.
- Calling the `save_to_img()` method will save the visualization results to the specified `save_path`. If a directory is specified, the saved path will be `save_path/{your_img_basename}_seal_res_region1.{your_img_extension}`. If a file is specified, it will be saved directly to that file. (The pipeline usually contains multiple result images, so it is not recommended to specify a specific file path directly, as multiple images will be overwritten, and only the last image will be retained.)
* Additionally, you can obtain visualized images with results and prediction results through attributes, as follows:
<table>
<thead>
<tr>
<th>Attribute</th>
<th>Description</th>
</tr>
</thead>
<tr>
<tdrowspan="1"><code>json</code></td>
<tdrowspan="1">Get the prediction results in <code>json</code> format.</td>
</tr>
<tr>
<tdrowspan="2"><code>img</code></td>
<tdrowspan="2">Get the visualization results in <code>dict</code> format.</td>
</tr>
</table>
- The prediction results obtained through the `json` attribute are of dict type, with content consistent with what is saved by calling the `save_to_json()` method.
- The prediction results returned by the `img` attribute are of dict type. The keys are `layout_det_res`, `seal_res_region1`, and `preprocessed_img`, corresponding to three `Image.Image` objects: one for visualizing layout detection, one for visualizing seal text recognition results, and one for visualizing image preprocessing. If the image preprocessing sub-module is not used, `preprocessed_img` will not be included in the dictionary. If the layout region detection module is not used, `layout_det_res` will not be included.
## 3. Development Integration/Deployment
If the pipeline meets your requirements for inference speed and accuracy, you can proceed directly with development integration/deployment.
If you need to integrate the pipeline into your Python project, you can refer to the example code in [2.2 Python Script Method](#22-python脚本方式集成).
In addition, PaddleX also provides three other deployment methods, which are detailed as follows:
🚀 High-Performance Inference: In real-world production environments, many applications have stringent performance requirements for deployment strategies, especially in terms of response speed, to ensure efficient system operation and a smooth user experience. To address this, PaddleOCR offers high-performance inference capabilities aimed at deeply optimizing the performance of model inference and pre/post-processing, thereby significantly accelerating the end-to-end process. For detailed high-performance inference procedures, please refer to [High-Performance Inference](../deployment/high_performance_inference.md).
☁️ Service Deployment: Service deployment is a common form of deployment in real-world production environments. By encapsulating inference functionality into a service, clients can access these services via network requests to obtain inference results. For detailed production service deployment procedures, please refer to [Serving](../deployment/serving.md).
Below are the API references for basic serving deployment and multi-language service invocation examples:
<details><summary>API Reference</summary>
<p>For the main operations provided by the service:</p>
<ul>
<li>The HTTP request method is POST.</li>
<li>The request body and response body are both JSON data (JSON objects).</li>
<li>When the request is processed successfully, the response status code is <code>200</code>, and the attributes of the response body are as follows:</li>
</ul>
<table>
<thead>
<tr>
<th>Name</th>
<th>Type</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr>
<td><code>logId</code></td>
<td><code>string</code></td>
<td>The UUID of the request.</td>
</tr>
<tr>
<td><code>errorCode</code></td>
<td><code>integer</code></td>
<td>Error code. Fixed as <code>0</code>.</td>
</tr>
<tr>
<td><code>errorMsg</code></td>
<td><code>string</code></td>
<td>Error message. Fixed as <code>"Success"</code>.</td>
</tr>
<tr>
<td><code>result</code></td>
<td><code>object</code></td>
<td>The result of the operation.</td>
</tr>
</tbody>
</table>
<ul>
<li>When the request is not processed successfully, the attributes of the response body are as follows:</li>
</ul>
<table>
<thead>
<tr>
<th>Name</th>
<th>Type</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr>
<td><code>logId</code></td>
<td><code>string</code></td>
<td>The UUID of the request.</td>
</tr>
<tr>
<td><code>errorCode</code></td>
<td><code>integer</code></td>
<td>Error code. Same as the response status code.</td>
</tr>
<tr>
<td><code>errorMsg</code></td>
<td><code>string</code></td>
<td>Error message.</td>
</tr>
</tbody>
</table>
<p>The main operations provided by the service are as follows:</p>
<ul>
<li><b><code>infer</code></b></li>
</ul>
<p>Obtain the seal text recognition result.</p>
<p><code>POST /seal-recognition</code></p>
<ul>
<li>The attributes of the request body are as follows:</li>
</ul>
<table>
<thead>
<tr>
<th>Name</th>
<th>Type</th>
<th>Description</th>
<th>Required</th>
</tr>
</thead>
<tbody>
<tr>
<td><code>file</code></td>
<td><code>string</code></td>
<td>The URL of an image or PDF file accessible by the server, or the Base64-encoded content of the file. By default, for PDF files exceeding 10 pages, only the content of the first 10 pages will be processed.<br/>
To remove the page limit, please add the following configuration to the pipeline configuration file:
<pre><code>Serving:
extra:
max_num_input_imgs: null
</code></pre></td>
<td>Yes</td>
</tr>
<tr>
<td><code>fileType</code></td>
<td><code>integer</code> | <code>null</code></td>
<td>The type of file. <code>0</code> indicates a PDF file, <code>1</code> indicates an image file. If this attribute is not present in the request body, the file type will be inferred from the URL.</td>
<td>No</td>
</tr>
<tr>
<td><code>useDocOrientationClassify</code></td>
<td><code>boolean</code> | <code>null</code></td>
<td>Please refer to the description of the <code>use_doc_orientation_classify</code> parameter of the pipeline object's <code>predict</code> method.</td>
<td>No</td>
</tr>
<tr>
<td><code>useDocUnwarping</code></td>
<td><code>boolean</code> | <code>null</code></td>
<td>Please refer to the description of the <code>use_doc_unwarping</code> parameter of the pipeline object's <code>predict</code> method.</td>
<td>No</td>
</tr>
<tr>
<td><code>useLayoutDetection</code></td>
<td><code>boolean</code> | <code>null</code></td>
<td>Please refer to the description of the <code>use_layout_detection</code> parameter of the pipeline object's <code>predict</code> method.</td>
<td>No</td>
</tr>
<tr>
<td><code>layoutThreshold</code></td>
<td><code>number</code> | <code>null</code></td>
<td>Please refer to the description of the <code>layout_threshold</code> parameter of the pipeline object's <code>predict</code> method.</td>
<td>No</td>
</tr>
<tr>
<td><code>layoutNms</code></td>
<td><code>boolean</code> | <code>null</code></td>
<td>Please refer to the description of the <code>layout_nms</code> parameter of the pipeline object's <code>predict</code> method.</td>
<td>Please refer to the description of the <code>layout_unclip_ratio</code> parameter of the pipeline object's <code>predict</code> method.</td>
<td>No</td>
</tr>
<tr>
<td><code>layoutMergeBboxesMode</code></td>
<td><code>string</code> | <code>null</code></td>
<td>Please refer to the description of the <code>layout_merge_bboxes_mode</code> parameter of the pipeline object's <code>predict</code> method.</td>
<td>No</td>
</tr>
<tr>
<td><code>sealDetLimitSideLen</code></td>
<td><code>integer</code> | <code>null</code></td>
<td>Please refer to the description of the <code>seal_det_limit_side_len</code> parameter of the pipeline object's <code>predict</code> method.</td>
<td>No</td>
</tr>
<tr>
<td><code>sealDetLimitType</code></td>
<td><code>string</code> | <code>null</code></td>
<td>Please refer to the description of the <code>seal_det_limit_type</code> parameter of the pipeline object's <code>predict</code> method.</td>
<td>No</td>
</tr>
<tr>
<td><code>sealDetThresh</code></td>
<td><code>number</code> | <code>null</code></td>
<td>Please refer to the description of the <code>seal_det_thresh</code> parameter of the pipeline object's <code>predict</code> method.</td>
<td>No</td>
</tr>
<tr>
<td><code>sealDetBoxThresh</code></td>
<td><code>number</code> | <code>null</code></td>
<td>Please refer to the description of the <code>seal_det_box_thresh</code> parameter of the pipeline object's <code>predict</code> method.</td>
<td>No</td>
</tr>
<tr>
<td><code>sealDetUnclipRatio</code></td>
<td><code>number</code> | <code>null</code></td>
<td>Please refer to the description of the <code>seal_det_unclip_ratio</code> parameter of the pipeline object's <code>predict</code> method.</td>
<td>No</td>
</tr>
<tr>
<td><code>sealRecScoreThresh</code></td>
<td><code>number</code> | <code>null</code></td>
<td>Please refer to the description of the <code>seal_rec_score_thresh</code> parameter of the pipeline object's <code>predict</code> method.</td>
<td>No</td>
</tr>
</tbody>
</table>
<ul>
<li>When the request is processed successfully, the <code>result</code> in the response body has the following properties:</li>
</ul>
<table>
<thead>
<tr>
<th>Name</th>
<th>Type</th>
<th>Meaning</th>
</tr>
</thead>
<tbody>
<tr>
<td><code>sealRecResults</code></td>
<td><code>object</code></td>
<td>The seal text recognition result. The array length is 1 (for image input) or the actual number of document pages processed (for PDF input). For PDF input, each element in the array represents the result of each page actually processed in the PDF file.</td>
</tr>
<tr>
<td><code>dataInfo</code></td>
<td><code>object</code></td>
<td>Information about the input data.</td>
</tr>
</tbody>
</table>
<p>Each element in <code>sealRecResults</code> is an <code>object</code> with the following properties:</p>
<table>
<thead>
<tr>
<th>Name</th>
<th>Type</th>
<th>Meaning</th>
</tr>
</thead>
<tbody>
<tr>
<td><code>prunedResult</code></td>
<td><code>object</code></td>
<td>A simplified version of the <code>res</code> field in the JSON representation generated by the <code>predict</code> method of the production object, where the <code>input_path</code> and the <code>page_index</code> fields are removed.</td>
</tr>
<tr>
<td><code>outputImages</code></td>
<td><code>object</code> | <code>null</code></td>
<td>See the description of the <code>img</code> attribute of the result of the pipeline prediction. The images are in JPEG format and encoded in Base64.</td>
</tr>
<tr>
<td><code>inputImage</code></td>
<td><code>string</code> | <code>null</code></td>
<td>The input image. The image is in JPEG format and encoded in Base64.</td>
</tr>
</tbody>
</table></details>
<details><summary>Multi-language Service Invocation Example</summary>
for i, res in enumerate(result["sealRecResults"]):
print(res["prunedResult"])
for img_name, img in res["outputImages"].items():
img_path = f"{img_name}_{i}.jpg"
with open(img_path, "wb") as f:
f.write(base64.b64decode(img))
print(f"Output image saved at {img_path}")
</code></pre></details>
</details>
<br/>
## 4. Custom Development
If the default model weights provided by the seal text recognition pipeline do not meet your requirements in terms of accuracy or speed, you can try to <b>fine-tune</b> the existing models using <b>your own domain-specific or application data</b> to improve the recognition performance of the seal text recognition pipeline in your scenario.
Since the seal text recognition pipeline consists of several modules, if the pipeline's performance does not meet expectations, the issue may arise from any one of these modules. You can analyze images with poor recognition results to identify which module is problematic and refer to the corresponding fine-tuning tutorial links in the table below for model fine-tuning.
<table>
<thead>
<tr>
<th>Scenario</th>
<th>Fine-Tuning Module</th>
<th>Fine-Tuning Reference Link</th>
</tr>
</thead>
<tbody>
<tr>
<td>Inaccurate or missing seal position detection</td>
