1. fetchSubFileDataList to get the collection of sub-photos.
2. Use fetchFileData to download the sub photos one by one.
It should be noted that when downloading continuously, the next photo needs to be downloaded after the previous photo's download task is finished, i.e. the callback indicates failure or success.
Some aircraft have cameras and gimbal cameras that automatically compose panoramas after taking panoramic photos, so there is no need to perform the first step.
Additional information: Mavic 2 pro does not support acquiring panoramic sub-images, and the camera does not synthesize panoramic images by itself.