def load_json_annotations(self):
        """Load json annotation file to get video information."""
        video_infos = mmcv.load(self.ann_file)
        num_videos = len(video_infos)
        path_key = 'frame_dir' if 'frame_dir' in video_infos[0] else 'filename'
        for i in range(num_videos):
            path_value = video_infos[i][path_key]
            if self.data_prefix is not None:
                path_value = osp.join(self.data_prefix, path_value)
            video_infos[i][path_key] = path_value
            if self.multi_class:
                assert self.num_classes is not None
            else:
                assert len(video_infos[i]['label']) == 1
                video_infos[i]['label'] = video_infos[i]['label'][0]
        return video_infos
Load json annotation file to get video information.
EVA-01/video/datasets/build.py