HarmonyOS NEXT AI基础视觉服务-文字识别

// 导入功能模块
import { camera, cameraPicker } from '@kit.CameraKit';
import { fileIo } from '@kit.CoreFileKit';
import image from '@ohos.multimedia.image';
import { textRecognition } from '@kit.CoreVisionKit';

// 创建相机选择器实例
const res = await cameraPicker.pick(getContext(), [
  cameraPicker.PickerMediaType.PHOTO
], {
  cameraPosition: camera.CameraPosition.CAMERA_POSITION_BACK
});

// 获取拍摄的图片URI
const imageUri = res.resultUri;

// 将图片转换为可识别的像素图
const fileSource = await fileIo.open(imageUri, fileIo.OpenMode.READ_ONLY);
const imageSource = image.createImageSource(fileSource.fd);
const pixelMap = await imageSource.createPixelMap();

// 配置视觉识别参数
let visionInfo: textRecognition.VisionInfo = {
  pixelMap: pixelMap
};

// 执行文字识别并获取结果
const recognitionResult = await textRecognition.recognizeText(visionInfo);
this.text = recognitionResult.value;

@Entry
@Component
struct TextRecognition {
  @State text: string = '';

  // 按钮点击事件处理
  async openCamera() {
    // 整合上述步骤的完整调用逻辑
  }

  build() {
    Column() {
      Button('拍照 文字识别')
        .onClick(() => this.openCamera())
      
      Text(this.text)
        .fontSize(20)
        .margin(10)
    }
    .padding(20)
  }
}

// 原始代码保持完整，仅添加说明注释
import { camera, cameraPicker } from '@kit.CameraKit';
import { fileIo } from '@kit.CoreFileKit';
import image from '@ohos.multimedia.image';
import { textRecognition } from '@kit.CoreVisionKit';

@Entry
@Component
struct TextRecognition {
  @State text: string = '';

  // 主功能方法：整合相机调用与文字识别
  async openCamera() {
    // 步骤1：调用相机拍摄
    const res = await cameraPicker.pick(getContext(), [cameraPicker.PickerMediaType.PHOTO], {
      cameraPosition: camera.CameraPosition.CAMERA_POSITION_BACK
    })

    // 步骤2：检查OCR能力可用性
// 使用canIUse接口检测设备是否支持文字识别能力
    if (canIUse('SystemCapability.AI.OCR.TextRecognition')) {
      // 步骤3：处理图像文件
      const fileSource = await fileIo.open(res.resultUri, fileIo.OpenMode.READ_ONLY);
      const imageSource = image.createImageSource(fileSource.fd);
      const chooseImage = await imageSource.createPixelMap();

      // 步骤4：执行文字识别
      let visionInfo: textRecognition.VisionInfo = {
        pixelMap: chooseImage
      };
      const data = await textRecognition.recognizeText(visionInfo);
      
      // 更新识别结果到界面
      this.text = data.value
    }
  }

  // UI布局
  build() {
    Column() {
      Button('拍照 文字识别')
        .onClick(() => {
          this.openCamera()
        })
      
      Text(this.text)
        .fontSize(20)
        .margin(10)
    }
    .height('100%')
    .width('100%')
  }
}