Supported video formats
Buffer currently supports videos up to 1GB in the file formats of mp4, mov, or avi. Buffer converts uploaded videos to MP4 encoded with H264, and a maximum resolution of 1280x720 (HD). Larger files are likely to be compressed to ensure they can be posted to the social network, but quality loss should be minimal. Unfortunately, we can't support Apple ProRes or raw camera formats like ARRI and RED at this time. For more information on sharing videos through Buffer, feel free to check out this full guide.