If YouTube won’t accept a video upload, or the video never completes “Processing” on YouTube, try re-encoding the video with FFmpeg. Sometimes lossy conversion is necessary to achieve the YouTube recommended upload settings.

Periscope video downloads use MPEG TS container with .ts file extension. These .ts files can be played back in VLC or similar to confirm content. A lossless conversion to YouTube is possible with:

ffmpeg -i pscp.ts -bsf:a aac_adtstoasc -codec copy -max_muxing_queue_size 1000 pscp.mp4

The FFmpeg option -max_muxing_queue_size is an arbitrary parameter. The default queue size is sometimes not large enough:

Too many packets buffered for output stream 0:1.

• Do not use .mkv extension for YouTube uploads, it will fail to process.
• certain formats like AV1 or FFV1 will fail to finish processing the upload
• after completing Uploading, video should start Processing in less than 5 minutes. If not, it will probably never actually work.

Uploads that don’t finish conversion processing after upload are not viewable on YouTube.