Flutter？获取视频第一帧

Question

Flutter项目中如何获取本地视频文件的第一帧？这是我的代码：

ImagePicker.pickVideo(source: ImageSource.camera).then((File file) {
  if (file != null && mounted) {
    //I got the video file here, but I want to get the first frame of the video.
  }
 });
},

Answer 1

首先，从文件对象获取文件路径并将其传递给下面的方法，该方法使用video_thumbnail lib 生成缩略图

Future<File> genThumbnailFile(String path) async {
    final fileName = await VideoThumbnail.thumbnailFile(
      video: path,
      thumbnailPath: (await getTemporaryDirectory()).path,
      imageFormat: ImageFormat.PNG,
      maxHeight: 100, // specify the height of the thumbnail, let the width auto-scaled to keep the source aspect ratio
      quality: 75,
    );
    File file = File(fileName);
    return file;
  }

其次，要使用它，您需要使用调用在另一个方法中接收 File 对象await，然后setState()更新文件。

 File file = await genThumbnailFile(filePath);
 setState(() {});

最后，使用类似的文件

Image.file(file, fit: BoxFit.cover,)

Answer 2

String thumb = await Thumbnails.getThumbnail(
    thumbnailFolder:'[FOLDER PATH TO STORE THUMBNAILS]', // creates the specified path if it doesnt exist
    videoFile: '[VIDEO PATH HERE]',
    imageType: ThumbFormat.PNG,
    quality: 30);

/*
* thumbnailFolder property can be omitted if you dont wish to keep the generated thumbails past each usage
*/