paddle ocr
paddle ocr笔记
准备工作
- 下载字典ppocr_keys_v1.txt,下标从1开始
- 模型转换
reference
to onnx
下载模型,或者直接使用python跑一下并且把本地模型拿过来用,一共三个模型:文本检测,文本方向校准,文字识别模型
paddle2onnx --model_dir ./det/ch/ch_PP-OCRv4_det_infer --model_filename inference.pdmodel --params_filename inference.pdiparams --save_file ./det-model.onnx --opset_version 11 --enable_onnx_checker True
paddle2onnx --model_dir ./rec/ch/ch_PP-OCRv4_rec_infer --model_filename inference.pdmodel --params_filename inference.pdiparams --save_file ./rec-model.onnx --opset_version 11 --enable_onnx_checker True
paddle2onnx --model_dir ./cls/ch_ppocr_mobile_v2.0_cls_infer --model_filename inference.pdmodel --params_filename inference.pdiparams --save_file ./cls-padmodel.onnx --opset_version 11 --enable_onnx_checker True
文本检测
import onnxruntime
import cv2
import numpy as np
# 读取图片
# image = cv2.imread("chinese.png")
image = cv2.imread("none.png")
# 加载 ONNX 文本检测模型
det_session = onnxruntime.InferenceSession("./onnx/det-model.onnx")
# 预处理
det_input = cv2.resize(image, (640, 640)) / 255.0 # 归一化
det_input = np.transpose(det_input, (2, 0, 1))[np.newaxis, :, :, :].astype(np.float32)
# 推理
input_name = det_session.get_inputs()[0].name
output_name = det_session.get_outputs()[0].name
det_output = det_session.run([output_name], {input_name: det_input})[0]
# 获取非零值的索引(文本区域)
non_zero_indices = np.nonzero(det_output)
print(f'--------------------------')
print(f'len:{len(non_zero_indices[0])}')
# 打印非零值的索引及对应的值
for i in range(len(non_zero_indices[0])):
print(f'--------------------------')
coords = tuple(non_zero_indices[j][i] for j in range(len(non_zero_indices)))
print(f"坐标: {coords}, 值: {det_output[coords]}")
文本检测
import onnxruntime
import cv2
import numpy as np
# 读取图片
# image = cv2.imread("chinese.png")
# image = cv2.imread("none.png")
image = cv2.imread("oneline.png")
# 加载 ONNX 文本检测模型
det_session = onnxruntime.InferenceSession("./onnx/det-model.onnx")
# 预处理
det_input = cv2.resize(image, (640, 640)) / 255.0 # 归一化
# det_input = image / 255.0 # 归一化
det_input = np.transpose(det_input, (2, 0, 1))[np.newaxis, :, :, :].astype(np.float32)
# 推理
input_name = det_session.get_inputs()[0].name
output_name = det_session.get_outputs()[0].name
det_output = det_session.run([output_name], {input_name: det_input})[0]
#
#
#
# 获取非零值的索引(文本区域)
# non_zero_indices = np.nonzero(det_output)
# print(f'--------------------------')
# print(f'len:{len(non_zero_indices[0])}')
# # 打印非零值的索引及对应的值
# for i in range(len(non_zero_indices[0])):
# print(f'--------------------------')
# coords = tuple(non_zero_indices[j][i] for j in range(len(non_zero_indices)))
# print(f"坐标: {coords}, 值: {det_output[coords]}")
# 5. 确保 `det_output` 是 4D (batch, channels, height, width)
print("det_output shape:", det_output.shape)
# 6. 获取二值化文本区域
box_thresh = 0.3
text_mask = (det_output[0, 0, :, :] > box_thresh).astype(np.uint8) * 255
# 7. 确保 `text_mask` 是单通道 2D 图像
print("text_mask shape:", text_mask.shape) # 应该是 (height, width)
# 8. 显示二值化结果(可选)
cv2.imshow("Text Mask", text_mask)
cv2.waitKey(0)
cv2.destroyAllWindows()
# 9. 确保 `text_mask` 兼容 OpenCV
if len(text_mask.shape) == 3:
text_mask = cv2.cvtColor(text_mask, cv2.COLOR_BGR2GRAY)
# 10. 轮廓检测
contours, _ = cv2.findContours(text_mask, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
# 11. 打印检测到的文本框
for contour in contours:
x, y, w, h = cv2.boundingRect(contour)
print(f"检测到的文本框: x={x}, y={y}, w={w}, h={h}")
文字识别
import onnxruntime
import cv2
import numpy as np
# 读取图片
image = cv2.imread("rec-cv2.imread.png")
target_height = 48
h, w = image.shape[:2]
new_w = int(w * (target_height / h))
new_w = max(32, (new_w // 32) * 32)
image = cv2.resize(image, (new_w, target_height));
print(f'resize: {image.shape}')
# image = cv2.imread("none.png")
# 加载 ONNX 文本检测模型
rec_session = onnxruntime.InferenceSession("./onnx/rec-model.onnx")
# 预处理
# rec_input = cv2.resize(image, (640, 640)) / 255.0 # 归一化
rec_input = image / 255.0 # 归一化
rec_input = np.transpose(rec_input, (2, 0, 1))[np.newaxis, :, :, :].astype(np.float32)
print(f'shape: {rec_input.shape}')
# 推理
input_name = rec_session.get_inputs()[0].name
output_name = rec_session.get_outputs()[0].name
print(f'input_name: {input_name}')
print(f'output_name: {output_name}')
rec_output = rec_session.run([output_name], {input_name: rec_input})[0]
with open('onnx/dict.txt', 'r', encoding='utf-8') as f:
dict_list = f.readlines()
dict_list = [line.strip() for line in dict_list]
# 返回下标的字典
dict_index = {i + 1: char for i, char in enumerate(dict_list)}
print(rec_output[0].shape)
# 假设 rec_output[0] 的 shape 为 (60, 6625)
probabilities = rec_output[0] # 取出 (60, 6625)
# Step 1: 找到每个时间步概率最高的索引
max_indices = np.argmax(probabilities, axis=1) # shape: (60,)
# print(f'--dict: {dict_index}')
# Step 2: CTC 处理(去重)
decoded_text = []
prev_index = -1 # 记录前一个索引,避免重复
for index in max_indices:
if index != prev_index and index in dict_index: # 避免重复 & 确保索引合法
print(f'--index: {index}, dict[{index}] = dict_index[{index}]')
decoded_text.append(dict_index[index])
prev_index = index
# Step 3: 转换为字符串
decoded_text = "".join(decoded_text)
print("识别结果:", decoded_text)