Cheapest AI person swap on Sume: the 5-second Recast floor

The cheapest valid H3 Max Recast job on Sume is a 5 second source at 768p: 5 seconds at $0.375 is $1.875. At 1080p the same clip is $2.8125. A source shorter than 5 seconds is rejected, so there is no cheaper tier to drop to.

That floor is useful as a unit: it is what you pay to find out whether a given face, outfit and shot survive a swap.

The floor by length

Seconds are rounded up before pricing, so a 5.2 second source bills as 6 seconds. The table shows the first few valid lengths.

Making a 5 second test slice

Do not test on the full clip. Cut the most demanding 5 seconds: the one with the closest face, the fastest head turn or the most movement. Sume's video trim takes one clip on your workspace's media.sume.com and a start plus either end or duration, and returns a new MP4. A clip that is not on media.sume.com has to be imported first, because the trim has no open-internet fetch.

Send the slice to Recast at 768p with your reference photos. If the face holds, run the full length; if it does not, you have spent $1.875 on that discovery instead of $11.25.

What the floor does not give you

A cheap test is not a guarantee. fal's schema says the source must be 5 to 30 seconds with no single shot over 15 seconds (fal H3 Max Recast API schema), and the hard part of a real clip is often the cut, which a 5 second slice may not contain. Test one slice that includes a cut if the final has them.

• Sume takes 1 to 4 person photos, so test with all the photos you plan to use.
• Do not assume two runs of the same slice match. Judge on stills and motion, not on one frame.
• Check the result with a frame sample from video_inspect before deciding.

How to use the floor

The five second floor shapes how you plan a cut. A one second reaction shot costs the same as five seconds, so group short shots that need the same swap into one source of at least five seconds, rather than sending several tiny files.

Use the floor for testing as well. A five second clip is the cheapest way to check that a reference photo and a prompt produce the identity you want before committing to a thirty second source. If the five second test fails, change the photo, not the clip length.

Remember that billing uses the rounded-up source length, so a 5.2 second source is priced as six seconds. Trim to the shot you need and do not pad with footage you are not going to use.

What a five second test costs

At 768p a five second Recast costs $1.875, and at 1080p $2.8125 before rounding to cents on the invoice. Ten tests at 768p cost $18.75. That is the price of choosing a reference photo with evidence instead of a guess.

Keep the test brief short. Name the person to replace and the person to insert in one sentence, and use a photo with a clear face and even light. Record which photo and prompt produced the best test so the full run starts from the winner.

• Test at 768p, which is the default on Sume, and run the final clip at 1080p only if the client needs it.
• Keep every test result URL until the client signs off.