目录

如何为AI合成的媒体文件添加隐式标识

问题现象

根据HarmonyOS应用上架要求，对于人工智能合成的内容，需要在合成内容的文件元数据中添加隐式标识。如何为人工智能合成的媒体文件（图片、音频、视频）添加文件隐式标识。

背景知识

解决方案

对于音视频媒体文件可以使用ffmpeg工具为音视频文件添加元数据，在HarmonyOS中可以使用三方库@ohos/mp4parser(V2.0.7)调用ffmpeg命令为音视频文件添加隐式标识。对于图片文件，通过modifyImageProperty接口将隐式元数据标识添加到图片的EXIF属性UserComment中。

  1. 对于人工智能合成的音频（m4a, mp3）以及视频文件(mp4, mkv)，直接使用三方库@ohos/mp4parser(V2.0.7)调用ffmpeg命令添加文件隐式标识。参考代码如下：
    const AV_AIGC_METADATA =
  '{"Label":"value1","ContentProducer":"value2","ProduceID":"value3","ReservedCode1":"value4","ContentPropagator":"value5","PropagateID":"value6","ReservedCode2":"value7"}';


/**
 *
 * @param inputPath 输入音视频文件的沙箱路径（无隐式标识）
 * @param outputPath 输出文件的沙箱路径（添加隐式标识）
 * @param aigcMetadata 需要写入的AIGC文件元数据
 * @returns
 */
async function addAIGC4AVFile(inputPath: string, outputPath: string, aigcMetadata: string): Promise<void> {
  let callback: ICallBack = {
    callBackResult: (code: number) => {
      if (code === 0) {
        console.info('Add aigc metadata succeed');
      } else {
        console.error('Add aigc metadata failed');
      }
    },
  };
  let cmd =
    `ffmpeg -i ${inputPath} -metadata AIGC="${aigcMetadata}" -movflags use_metadata_tags -c copy ${outputPath} -y`;
  MP4Parser.ffmpegCmd(cmd, callback);
}
  2. 对于人工智能合成的图片文件（jpg、png），通过modifyImageProperty接口添加文件隐式标识到图片的EXIF属性UserComment中。参考代码如下：
    const IMAGE_AIGC_METADATA =
  '{"AIGC":{"Label":"value1","ContentProducer":"value2","ProduceID":"value3","ReservedCode1":"value4","ContentPropagator":"value5","PropagateID":"value6","ReservedCode2":"value7"}}';


/**
 *
 * @param imageFilePath 输入图片文件的沙箱路径
 * @param aigcMetadata 需要写入的AIGC文件元数据
 */
async function addAIGC4ImageFile(imageFilePath: string, aigcMetadata: string) {
  let imageSource: image.ImageSource | undefined;
  try {
    imageSource = image.createImageSource(imageFilePath);
    await imageSource.modifyImageProperty(image.PropertyKey.USER_COMMENT, aigcMetadata);
    console.info(`Add aigc metadata succeed.`);
  } catch (error) {
    console.error(`Failed to invoke ImageSource.modifyImageProperty. Cause: ${JSON.stringify(error)}`);
  } finally {
    await imageSource?.release();
  }
}

完整参考代码如下：

import { ICallBack, MP4Parser } from '@ohos/mp4parser';
import image from '@ohos.multimedia.image';
import { fileIo } from '@kit.CoreFileKit';


const AV_AIGC_METADATA =
  '{"Label":"value1","ContentProducer":"value2","ProduceID":"value3","ReservedCode1":"value4","ContentPropagator":"value5","PropagateID":"value6","ReservedCode2":"value7"}';


/**
 *
 * @param inputPath 输入音视频文件的沙箱路径（无隐式标识）
 * @param outputPath 输出文件的沙箱路径（添加隐式标识）
 * @param aigcMetadata 需要写入的AIGC文件元数据
 * @returns
 */
async function addAIGC4AVFile(inputPath: string, outputPath: string, aigcMetadata: string): Promise<void> {
  let callback: ICallBack = {
    callBackResult: (code: number) => {
      if (code === 0) {
        console.info('Add aigc metadata succeed');
      } else {
        console.error('Add aigc metadata failed');
      }
    },
  };
  let cmd =
    `ffmpeg -i ${inputPath} -metadata AIGC="${aigcMetadata}" -movflags use_metadata_tags -c copy ${outputPath} -y`;
  MP4Parser.ffmpegCmd(cmd, callback);
}


const IMAGE_AIGC_METADATA =
  '{"AIGC":{"Label":"value1","ContentProducer":"value2","ProduceID":"value3","ReservedCode1":"value4","ContentPropagator":"value5","PropagateID":"value6","ReservedCode2":"value7"}}';


/**
 *
 * @param imageFilePath 输入图片文件的沙箱路径
 * @param aigcMetadata 需要写入的AIGC文件元数据
 */
async function addAIGC4ImageFile(imageFilePath: string, aigcMetadata: string) {
  let imageSource: image.ImageSource | undefined;
  try {
    imageSource = image.createImageSource(imageFilePath);
    await imageSource.modifyImageProperty(image.PropertyKey.USER_COMMENT, aigcMetadata);
    console.info(`Add aigc metadata succeed.`);
  } catch (error) {
    console.error(`Failed to invoke ImageSource.modifyImageProperty. Cause: ${JSON.stringify(error)}`);
  } finally {
    await imageSource?.release();
  }
}


async function copyFile2Sandbox(rawFilePath: string, sandboxFilePath: string, context: Context) {
  let sandboxFile: fileIo.File | undefined;
  try {
    sandboxFile = await fileIo.open(sandboxFilePath, fileIo.OpenMode.CREATE | fileIo.OpenMode.WRITE_ONLY);
    let content = await context.resourceManager.getRawFileContent(rawFilePath);
    await fileIo.write(sandboxFile.fd, content.buffer.slice(0));
  } catch (error) {
    console.error(`Failed to copy rawfile to sandbox. Cause: ${JSON.stringify(error)}`);
  } finally {
    if (sandboxFile) {
      await fileIo.close(sandboxFile.fd);
    }
  }
}


@Entry
@Component
struct Index {
  build() {
    Column({ space: 20 }) {
      Button('Video')
        .padding(9)
        .fontSize(30)
        .onClick(async () => {
          let context = this.getUIContext().getHostContext() as Context;
          const inputPath = context.filesDir + '/input.mp4';
          const outputPath = context.filesDir + '/output.mp4';
          await copyFile2Sandbox('input.mp4', inputPath, context); // input.mp4为rawfile文件，根据实际使用的文件替换
          await addAIGC4AVFile(inputPath, outputPath, AV_AIGC_METADATA);
        });


      Button('Audio')
        .padding(9)
        .fontSize(30)
        .onClick(async () => {
          let context = this.getUIContext().getHostContext() as Context;
          const inputPath = context.filesDir + '/input.m4a';
          const outputPath = context.filesDir + '/output.m4a';
          await copyFile2Sandbox('input.m4a', inputPath, context); // input.m4a为rawfile文件，根据实际使用的文件替换
          await addAIGC4AVFile(inputPath, outputPath, AV_AIGC_METADATA);
        });


      Button('Image')
        .padding(9)
        .fontSize(30)
        .onClick(async () => {
          let context = this.getUIContext().getHostContext() as Context;
          const inputPath = context.filesDir + '/image.jpg';
          await copyFile2Sandbox('image.jpg', inputPath, context); // image.jpg为rawfile文件，根据实际使用的文件替换
          await addAIGC4ImageFile(inputPath, IMAGE_AIGC_METADATA);
        });
    }
    .width('100%')
    .height('100%')
    .justifyContent(FlexAlign.Center)
    .alignItems(HorizontalAlign.Center);
  }
}