Platform specs ask for bitrate and GOP: what Sume lets you set

Platform specs often list encoder settings such as bitrate, GOP length or B frames, but Sume's media APIs do not take them. A request with codec, crf, ffmpeg, filter or cmd fields is rejected with ffmpeg_fields_rejected. What you can set is output size, frame rate, whether to keep audio, and whether a trim re-encodes or copies.

What the specs ask for

The values are from each vendor page, read 2026-10-08.

What you can set on Sume

These are the controls the docs list.

How to read the gap

Many of these asks are about the final platform transcode, not about your upload. YouTube states its settings as recommended upload encoding, and platforms re-encode whatever you send. The fields Sume refuses are the ones you cannot verify from outside anyway.

What you can do is check the facts a file shows. Video inspect returns probe data, so you can read frame rate, size and duration from the output instead of assuming them. For the bitrate rows, compare file size with duration yourself: size in megabits divided by seconds.

• Choose fps 30 or 60 explicitly if the platform wants a fixed rate; omitting fps on Timeline matches the sources.
• Use exact trim when you need a consistent H.264 file.
• Treat bitrate and GOP rows as platform guidance, not something Sume will set.

Cost of a spec check

One exact trim is $0.02 and one Timeline render is $0.10 per output minute. Probing the result with video inspect without a transcript adds no speech-to-text charge, because that is billed only for the transcript.

Verifying the output

Probe the file you get back rather than trusting the request. Video inspect returns the probe data for a Sume-hosted file, including duration and size, and video frames returns stills so you can look at the first and last frame, which is where encoder problems and stray black frames tend to show up.

If a number on the vendor page is a hard limit, such as a maximum file size, check the artifact's size after render and keep a margin. If it is a recommendation, such as a bitrate, treat the platform's own transcode as the final word. A file that passes every check you can run is the best input you can give that transcode.