40、验证码识别与图像水印技术解析

验证码识别与图像水印技术解析

1. 验证码识别模型

1.1 模型结构

BypassCaptcha 模型有着独特的结构，各层信息如下表所示：
| Layer (type) | Output shape | Params | Connected to |
| — | — | — | — |
| Image (Input Layer) | [(None, 200, 50, 1)] | 0 | [] |
| Conv1(conv2D) | (None, 200, 50, 32) | 320 | [‘image[0][0]’] |
| Pool1[MaxPooling2D] | (None, 100, 25, 32) | 0 | [‘conv1[0][0]’] |
| Conv2(conv2D) | (None, 100, 25, 64) | 18,496 | [‘pool1[0][0]’] |
| Pool2[MaxPooling2D] | (None, 50, 12, 64) | 0 | [‘conv2[0][0]’] |
| Reshape(Reshape) | (None, 50, 768) | 0 | [‘pool2[0][0]’] |
| Dense1(Dense) | (None, 50, 64) | 49,216 | [‘reshape[0][0]’] |
| Dropout_2(Dropout) | (None, 50, 64) | 0 | [‘dense1[0][0]’] |
| Bidirectional_4(Bidirectional) | (None, 50, 256)