docs/version3.x/inference_deployment/cross_platform/android_deployment.md
本项目是 PaddleOCR v6 在 Android 平台的部署示例,基于 ONNX Runtime 实现移动端 OCR 推理。项目采用 SDK 与 Demo 分离 架构,SDK 模块可独立集成到第三方应用。
ppocr-android/
├── ppocr-sdk/ # OCR SDK(Android Library)
│ ├── src/main/
│ │ ├── assets/models/ # 模型文件目录
│ │ │ ├── det/ # 检测模型:inference.onnx
│ │ │ └── rec/ # 识别模型:inference.onnx, inference.yml
│ │ └── java/com/paddle/ocr/
│ │ ├── PaddleOCR.kt # [公开 API] SDK 入口
│ │ ├── PaddleOCRConfig.kt # [公开 API] 推理参数配置
│ │ └── ...
│ └── build.gradle.kts
├── app/ # Demo App
│ ├── src/main/java/com/paddle/ocr/demo/
│ │ ├── OCRApplication.kt # 初始化 SDK
│ │ └── ui/ # Compose UI
│ └── build.gradle.kts
├── run_benchmark.sh # 性能测试脚本
└── README.md
| 依赖 | 版本 |
|---|---|
| Android Studio | Ladybug (2024.2+) |
| JDK | 17 |
| Kotlin | 2.1.0 |
| minSdk | 26 (Android 8.0) |
| ONNX Runtime | 1.21.1 |
| OpenCV | 4.5.3 |
git clone https://github.com/PaddlePaddle/PaddleOCR.git
cd PaddleOCR/deploy/ppocr-android
本项目支持以下模型:
| 模型 | HuggingFace | BOS |
|---|---|---|
| PP-OCRv6_small | 检测模型 / 识别模型 | 检测模型 / 识别模型 |
| PP-OCRv6_tiny | 检测模型 / 识别模型 | 检测模型 / 识别模型 |
| PP-OCRv5_mobile | 检测模型 / 识别模型 | 检测模型 / 识别模型 |
下载并解压后,将文件放入 ppocr-sdk/src/main/assets/models/ 目录:
inference.onnx 放入 models/det/inference.onnx 和 inference.yml 放入 models/rec/# 编译 Debug APK
./gradlew :app:assembleDebug
# 安装到设备
./gradlew :app:installDebug
或使用 Android Studio 直接运行。
ppocr-sdk/ 复制到项目根目录settings.gradle.kts 添加:
include(":ppocr-sdk")
build.gradle.kts 添加:
implementation(project(":ppocr-sdk"))
# 构建 AAR
./gradlew :ppocr-sdk:assembleRelease
AAR 输出:ppocr-sdk/build/outputs/aar/ppocr-sdk-release.aar
在 App 模块 build.gradle.kts 添加:
dependencies {
implementation(files("libs/ppocr-sdk-release.aar"))
// AAR 不传递依赖,需手动添加
implementation("com.microsoft.onnxruntime:onnxruntime-android:1.21.1")
implementation("com.quickbirdstudios:opencv:4.5.3")
implementation("org.jetbrains.kotlinx:kotlinx-coroutines-android:1.9.0")
}
// 默认配置
val ocr = PaddleOCR.create(context)
// 自定义配置
val ocr = PaddleOCR.create(
context = context,
config = PaddleOCRConfig(
detThresh = 0.3f,
detBoxThresh = 0.6f,
recScoreThresh = 0.0f,
recBatchSize = 1,
),
engineConfig = EngineConfig(numThreads = 4),
detModelAssetPath = "models/det/inference.onnx",
recModelAssetPath = "models/rec/inference.onnx",
recConfigAssetPath = "models/rec/inference.yml",
)
// 传入 Bitmap
val result = ocr.recognize(bitmap)
// 传入图片字节数据(推荐,与 Python 流程一致)
val result = ocr.recognize(imageBytes)
// 读取结果
result.results.forEach { item ->
println("文本: ${item.text}, 置信度: ${item.confidence}")
println("坐标: ${item.box.points}")
}
println("检测: ${result.detectionTimeMs}ms, 识别: ${result.recognitionTimeMs}ms")
ocr.release()
data class PaddleOCRConfig(
val detImgMode: String = "BGR", // 输入色彩模式
val detLimitSideLen: Int = 64, // 检测侧边长限制
val detLimitType: String = "min", // 限制策略
val detMaxSideLimit: Int = 4000, // 最长边上限
val detThresh: Float = 0.3f, // 二值化阈值
val detBoxThresh: Float = 0.6f, // 检测框置信度阈值
val detUnclipRatio: Float = 1.5f, // 检测框扩展比例
val detMaxCandidates: Int = 3000, // 最大候选框数
val detUseDilation: Boolean = false, // 是否膨胀
val detScoreMode: String = "fast", // 打分模式
val detBoxType: String = "quad", // 检测框类型
val recScoreThresh: Float = 0.0f, // 识别置信度阈值
val recBatchSize: Int = 1, // 识别批大小
)
data class OCRRunResult(
val results: List<OCRResult>, // 识别结果列表
val detectionTimeMs: Long, // 检测耗时
val recognitionTimeMs: Long, // 识别耗时
val totalTimeMs: Long, // 总耗时
val lineCount: Int, // 识别行数
// 详细计时...
)
data class OCRResult(
val box: OCRBox, // 检测框坐标
val text: String, // 识别文本
val confidence: Float, // 置信度
)
项目提供自动化性能测试脚本:
# 运行 benchmark(10次测试,3次预热)
./run_benchmark.sh 10 3
# 输出示例
╔═════════════════════════════════════════════════════════════════════════╗
║ PP-OCRv6 Speed Benchmark Results ║
╠═════════════════════════════════════════════════════════════════════════╣
║ Device: GM1900 | OS: Android 9 | Lines: 5 ║
║ Cold load: 158ms | Warmup: 3 | Measured: 10 ║
╠═════════════════════════════════════════════════════════════════════════╣
+-----------------------------+----------+----------+----------+----------+
| Stage | Mean ms | Stdev | P90 | Min ms|
+-----------------------------+----------+----------+----------+----------+
| Total pipeline | 420.40 | 6.37 | 427 | 413 |
+-----------------------------+----------+----------+----------+----------+
| Detection (total) | 348.70 | 4.67 | 356 | 343 |
| Preprocess | 33.30 | 2.90 | 36 | 28 |
| Inference | 311.00 | 2.93 | 315 | 304 |
| Postprocess | 4.40 | 0.49 | 5 | 4 |
| Recognition (total) | 66.20 | 3.16 | 68 | 64 |
| Preprocess | 3.00 | 0.89 | 4 | 2 |
| Inference | 60.60 | 3.14 | 63 | 58 |
| Postprocess | 2.60 | 0.92 | 4 | 1 |
| Pipeline overhead | 5.50 | 0.50 | 6 | 5 |
+-----------------------------+----------+----------+----------+----------+
╚═════════════════════════════════════════════════════════════════════════╝
PaddleOCR.create() 前需先调用 OpenCVUtils.init(context)create() 和 recognize() 都是 suspend 函数,需在协程中调用release() 释放资源ppocr-sdk/proguard-rules.pro