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TEXT RECOGNITION
DATA PREPARATION
PaddleOCR supports two data formats: LMDB
is used to train public data and evaluation algorithms; general data
is used to train your own data:
Please organize the dataset as follows:
The default storage path for training data is PaddleOCR/train_data
, if you already have a dataset on your disk, just create a soft link to the dataset directory:
ln -sf <path/to/dataset> <path/to/paddle_ocr>/train_data/dataset
- Dataset download
If you do not have a dataset locally, you can download it on the official website icdar2015. Also refer to DTRB,download the lmdb format dataset required for benchmark
If you want to reproduce the paper indicators of SRN, you need to download offline augmented data, extraction code: y3ry. The augmented data is obtained by rotation and perturbation of mjsynth and synthtext. Please unzip the data to {your_path}/PaddleOCR/train_data/data_lmdb_Release/training/path.
- Use your own dataset:
If you want to use your own data for training, please refer to the following to organize your data.
- Training set
First put the training images in the same folder (train_images), and use a txt file (rec_gt_train.txt) to store the image path and label.
- Note: by default, the image path and image label are split with \t, if you use other methods to split, it will cause training error
" Image file name Image annotation "
train_data/train_0001.jpg 简单可依赖
train_data/train_0002.jpg 用科技让复杂的世界更简单
PaddleOCR provides label files for training the icdar2015 dataset, which can be downloaded in the following ways:
# Training set label
wget -P ./train_data/ic15_data https://paddleocr.bj.bcebos.com/dataset/rec_gt_train.txt
# Test Set Label
wget -P ./train_data/ic15_data https://paddleocr.bj.bcebos.com/dataset/rec_gt_test.txt
The final training set should have the following file structure:
|-train_data
|-ic15_data
|- rec_gt_train.txt
|- train
|- word_001.png
|- word_002.jpg
|- word_003.jpg
| ...
- Test set
Similar to the training set, the test set also needs to be provided a folder containing all images (test) and a rec_gt_test.txt. The structure of the test set is as follows:
|-train_data
|-ic15_data
|- rec_gt_test.txt
|- test
|- word_001.jpg
|- word_002.jpg
|- word_003.jpg
| ...
- Dictionary
Finally, a dictionary ({word_dict_name}.txt) needs to be provided so that when the model is trained, all the characters that appear can be mapped to the dictionary index.
Therefore, the dictionary needs to contain all the characters that you want to be recognized correctly. {word_dict_name}.txt needs to be written in the following format and saved in the utf-8
encoding format:
l
d
a
d
r
n
In word_dict.txt
, there is a single word in each line, which maps characters and numeric indexes together, e.g "and" will be mapped to [2 5 1]
ppocr/utils/ppocr_keys_v1.txt
is a Chinese dictionary with 6623 characters.
ppocr/utils/ic15_dict.txt
is an English dictionary with 63 characters
ppocr/utils/dict/french_dict.txt
is a French dictionary with 118 characters
ppocr/utils/dict/japan_dict.txt
is a Japanese dictionary with 4399 characters
ppocr/utils/dict/korean_dict.txt
is a Korean dictionary with 3636 characters
ppocr/utils/dict/german_dict.txt
is a German dictionary with 131 characters
ppocr/utils/dict/en_dict.txt
is a English dictionary with 63 characters
You can use it on demand.
The current multi-language model is still in the demo stage and will continue to optimize the model and add languages. You are very welcome to provide us with dictionaries and fonts in other languages, If you like, you can submit the dictionary file to dict or corpus file to corpus and we will thank you in the Repo.
To customize the dict file, please modify the character_dict_path
field in configs/rec/rec_icdar15_train.yml
and set character_type
to ch
.
- Custom dictionary
If you need to customize dic file, please add character_dict_path field in configs/rec/rec_icdar15_train.yml to point to your dictionary path. And set character_type to ch.
- Add space category
If you want to support the recognition of the space
category, please set the use_space_char
field in the yml file to True
.
Note: use_space_char only takes effect when character_type=ch
TRAINING
PaddleOCR provides training scripts, evaluation scripts, and prediction scripts. In this section, the CRNN recognition model will be used as an example:
First download the pretrain model, you can download the trained model to finetune on the icdar2015 data:
cd PaddleOCR/
# Download the pre-trained model of MobileNetV3
wget -P ./pretrain_models/ https://paddleocr.bj.bcebos.com/dygraph_v2.0/en/rec_mv3_none_bilstm_ctc_v2.0_train.tar
# Decompress model parameters
cd pretrain_models
tar -xf rec_mv3_none_bilstm_ctc_v2.0_train.tar && rm -rf rec_mv3_none_bilstm_ctc_v2.0_train.tar
Start training:
# GPU training Support single card and multi-card training, specify the card number through --gpus
# Training icdar15 English data and saving the log as train_rec.log
python3 -m paddle.distributed.launch --gpus '0,1,2,3' tools/train.py -c configs/rec/rec_icdar15_train.yml
- Data Augmentation
PaddleOCR provides a variety of data augmentation methods. If you want to add disturbance during training, please set distort: true
in the configuration file.
The default perturbation methods are: cvtColor, blur, jitter, Gasuss noise, random crop, perspective, color reverse.
Each disturbance method is selected with a 50% probability during the training process. For specific code implementation, please refer to: img_tools.py
- Training
PaddleOCR supports alternating training and evaluation. You can modify eval_batch_step
in configs/rec/rec_icdar15_train.yml
to set the evaluation frequency. By default, it is evaluated every 500 iter and the best acc model is saved under output/rec_CRNN/best_accuracy
during the evaluation process.
If the evaluation set is large, the test will be time-consuming. It is recommended to reduce the number of evaluations, or evaluate after training.
- Tip: You can use the
-c
parameter to select multiple model configurations under theconfigs/rec/
path for training. The recognition algorithms supported by PaddleOCR are:
Configuration file | Algorithm | backbone | trans | seq | pred |
---|---|---|---|---|---|
rec_chinese_lite_train_v2.0.yml | CRNN | Mobilenet_v3 small 0.5 | None | BiLSTM | ctc |
rec_chinese_common_train_v2.0.yml | CRNN | ResNet34_vd | None | BiLSTM | ctc |
rec_chinese_lite_train.yml | CRNN | Mobilenet_v3 small 0.5 | None | BiLSTM | ctc |
rec_chinese_common_train.yml | CRNN | ResNet34_vd | None | BiLSTM | ctc |
rec_icdar15_train.yml | CRNN | Mobilenet_v3 large 0.5 | None | BiLSTM | ctc |
rec_mv3_none_bilstm_ctc.yml | CRNN | Mobilenet_v3 large 0.5 | None | BiLSTM | ctc |
rec_mv3_none_none_ctc.yml | Rosetta | Mobilenet_v3 large 0.5 | None | None | ctc |
rec_mv3_tps_bilstm_ctc.yml | STARNet | Mobilenet_v3 large 0.5 | tps | BiLSTM | ctc |
rec_mv3_tps_bilstm_attn.yml | RARE | Mobilenet_v3 large 0.5 | tps | BiLSTM | attention |
rec_r34_vd_none_bilstm_ctc.yml | CRNN | Resnet34_vd | None | BiLSTM | ctc |
rec_r34_vd_none_none_ctc.yml | Rosetta | Resnet34_vd | None | None | ctc |
rec_r34_vd_tps_bilstm_ctc.yml | STARNet | Resnet34_vd | tps | BiLSTM | ctc |
For training Chinese data, it is recommended to use
rec_chinese_lite_train_v2.0.yml. If you want to try the result of other algorithms on the Chinese data set, please refer to the following instructions to modify the configuration file:
co
Take rec_chinese_lite_train_v2.0.yml
as an example:
Global:
...
# Add a custom dictionary, such as modify the dictionary, please point the path to the new dictionary
character_dict_path: ppocr/utils/ppocr_keys_v1.txt
# Modify character type
character_type: ch
...
# Whether to recognize spaces
use_space_char: True
Optimizer:
...
# Add learning rate decay strategy
lr:
name: Cosine
learning_rate: 0.001
...
...
Train:
dataset:
# Type of dataset,we support LMDBDateSet and SimpleDataSet
name: SimpleDataSet
# Path of dataset
data_dir: ./train_data/
# Path of train list
label_file_list: ["./train_data/train_list.txt"]
transforms:
...
- RecResizeImg:
# Modify image_shape to fit long text
image_shape: [3, 32, 320]
...
loader:
...
# Train batch_size for Single card
batch_size_per_card: 256
...
Eval:
dataset:
# Type of dataset,we support LMDBDateSet and SimpleDataSet
name: SimpleDataSet
# Path of dataset
data_dir: ./train_data
# Path of eval list
label_file_list: ["./train_data/val_list.txt"]
transforms:
...
- RecResizeImg:
# Modify image_shape to fit long text
image_shape: [3, 32, 320]
...
loader:
# Eval batch_size for Single card
batch_size_per_card: 256
...
Note that the configuration file for prediction/evaluation must be consistent with the training.
- Multi-language
PaddleOCR also provides multi-language. The configuration file in configs/rec/multi_languages
provides multi-language configuration files. Currently, the multi-language algorithms supported by PaddleOCR are:
Configuration file | Algorithm name | backbone | trans | seq | pred | language | |
---|---|---|---|---|---|---|
rec_en_lite_train.yml | CRNN | Mobilenet_v3 small 0.5 | None | BiLSTM | ctc | English | |
rec_french_lite_train.yml | CRNN | Mobilenet_v3 small 0.5 | None | BiLSTM | ctc | French | |
rec_ger_lite_train.yml | CRNN | Mobilenet_v3 small 0.5 | None | BiLSTM | ctc | German | |
rec_japan_lite_train.yml | CRNN | Mobilenet_v3 small 0.5 | None | BiLSTM | ctc | Japanese | |
rec_korean_lite_train.yml | CRNN | Mobilenet_v3 small 0.5 | None | BiLSTM | ctc | Korean | |
The multi-language model training method is the same as the Chinese model. The training data set is 100w synthetic data. A small amount of fonts and test data can be downloaded on Baidu Netdisk,Extraction code:frgi.
If you want to finetune on the basis of the existing model effect, please refer to the following instructions to modify the configuration file:
Take rec_french_lite_train
as an example:
Global:
...
# Add a custom dictionary, such as modify the dictionary, please point the path to the new dictionary
character_dict_path: ./ppocr/utils/dict/french_dict.txt
...
# Whether to recognize spaces
use_space_char: True
...
Train:
dataset:
# Type of dataset,we support LMDBDateSet and SimpleDataSet
name: SimpleDataSet
# Path of dataset
data_dir: ./train_data/
# Path of train list
label_file_list: ["./train_data/french_train.txt"]
...
Eval:
dataset:
# Type of dataset,we support LMDBDateSet and SimpleDataSet
name: SimpleDataSet
# Path of dataset
data_dir: ./train_data
# Path of eval list
label_file_list: ["./train_data/french_val.txt"]
...
EVALUATION
The evaluation data set can be modified via configs/rec/rec_icdar15_reader.yml
setting of label_file_path
in EvalReader.
# GPU evaluation, Global.checkpoints is the weight to be tested
python3 -m paddle.distributed.launch --gpus '0' tools/eval.py -c configs/rec/rec_icdar15_reader.yml -o Global.checkpoints={path/to/weights}/best_accuracy
PREDICTION
- Training engine prediction
Using the model trained by paddleocr, you can quickly get prediction through the following script.
The default prediction picture is stored in infer_img
, and the weight is specified via -o Global.checkpoints
:
# Predict English results
python3 tools/infer_rec.py -c configs/rec/ch_ppocr_v2.0/rec_chinese_lite_train_v2.0.yml -o Global.checkpoints={path/to/weights}/best_accuracy TestReader.infer_img=doc/imgs_words/en/word_1.jpg
Input image:
Get the prediction result of the input image:
infer_img: doc/imgs_words/en/word_1.png
index: [19 24 18 23 29]
word : joint
The configuration file used for prediction must be consistent with the training. For example, you completed the training of the Chinese model with python3 tools/train.py -c configs/rec/ch_ppocr_v2.0/rec_chinese_lite_train_v2.0.yml
, you can use the following command to predict the Chinese model:
# Predict Chinese results
python3 tools/infer_rec.py -c configs/rec/ch_ppocr_v2.0/rec_chinese_lite_train_v2.0.yml -o Global.checkpoints={path/to/weights}/best_accuracy TestReader.infer_img=doc/imgs_words/ch/word_1.jpg
Input image:
Get the prediction result of the input image:
infer_img: doc/imgs_words/ch/word_1.jpg
index: [2092 177 312 2503]
word : 韩国小馆