mp4parser获得GPS定位

Question

亲爱的，
我在新的项目中，我需要从MP4视频访问GPS定位工作。这是我试过的代码，但得到空指针异常。

File videoFile = new File(videoFilePath); 
if (!videoFile.exists()) { 
    throw new FileNotFoundException("File " + videoFilePath + " not exists"); 
} 
if (!videoFile.canRead()) { 
    throw new IllegalStateException("No read permissions to file " + videoFilePath); 
} 
IsoFile isoFile = new IsoFile(videoFilePath); 
AppleNameBox nam = Path.getPath(isoFile, "/moov[0]/udta[0]/meta[0]/ilst/©xyz"); 
String xml = nam.getValue(); 

感谢，
嗡

Answer 1

此代码为我工作。当没有位置标签可用时，它给NPE。

private String readVideoLocation(String fullFilePath) throws Exception { 
    File videoFile = new File(fullFilePath); 
    if (!videoFile.exists()) { 
     throw new FileNotFoundException("File " + fullFilePath + " not exists"); 
    } 

    if (!videoFile.canRead()) { 
     throw new IllegalStateException("No read permissions to file " + fullFilePath); 
    } 

    FileDataSourceImpl fileDataSource = new FileDataSourceImpl(fullFilePath); 
    IsoFile isoFile = new IsoFile(fileDataSource); 

    AppleGPSCoordinatesBox locBox = Path.getPath(isoFile, "/moov[0]/udta[0]/meta[0]/ilst/©xyz"); 
    String xml = locBox.getValue(); 
    isoFile.close(); 
    return xml; 
}