Attach a 2–30 second clip below, start the instruction with “Extend the video by 8 seconds” and describe what happens next. Seedance 2.5 picks up on the last frame. Runs on Seedance 2.5.
An extension is new footage that begins exactly where your clip stops: same subject, same set, same light and grade, plus whatever you ask to happen next. It is the fix for a shot that ends one beat too early, a take that needs a longer hold for the edit, or a sequence you want to build out a few seconds at a time.
Each task uses the current generator quote for its model, duration, resolution and references. Identical settings cost the same credits on every plan; subscriptions do not reduce the task credit charge.
A paid user’s run on Open AI Image, shown unedited apart from compression. The source clip ends on a close-up of the climber’s hand on the pipe; the extension opens on that same frame and plays out the instruction in four timed stages.
The instruction opens with the goal (“Extend the source video forward by 10 seconds”), describes the last frame of the source so the model holds it, then lays out four timed stages: the mechanical shoulder sparks and seizes (0–3 s), the arm falls away and he drops to hang one-handed (3–5 s), a wide shot of him swinging over the shaft (5–8 s), and a close-up of the trembling hand holding on (8–10 s). It ends with style, diegetic sound cues and what must stay consistent.
[Generation Goal] Extend the source video forward by 10 seconds as a live-action cinematic climbing sequence. The central subject is Elion, and the primary event is Elion's exposed mechanical shoulder failing mid pull-up: the servos seize, that arm tears loose from the pipe, and he drops to hang by one flesh-and-blood arm over the open shaft. [Source Video] The source video defines Elion's identity, clothing, the mechanical shoulder, the rusted pipe, the wall plate, the lighting, and the film grade. Continue directly from the source video's last frame: close-up, Elion's chin just above the round rusted pipe, eyes looking up, jaw set, his left hand clamped over the top of the pipe beside the bolted steel wall plate, the polished steel mechanical shoulder showing through the torn dark jacket at the lower left of frame. Hold this composition, framing, and light for the opening moment before any new action begins. [Characters] Elion — tousled black hair, pale freckled skin, grey-blue eyes, torn charcoal canvas jacket. His right shoulder is mechanical: layered polished steel plates and exposed joint actuators with a thin orange wire, visible through the torn fabric. His right hand grips the pipe further to the left, just outside the frame. His left arm is flesh and blood. The output contains only one Elion throughout. [Scene] An abandoned brutalist concrete shaft: board-formed concrete walls, a square rusted steel plate bolted flat to the right-hand wall, and a single thick rusted pipe extending from the plate horizontally out into the open shaft. Below, the shaft falls away many storeys into deep shadow. Elion is a small figure against the enormous wall. The shaft is empty; no other people are present. [Stage 1 | 0-3 seconds] Initial state: the source video's last frame, exactly as described above. Primary event: Elion clenches his teeth and strains to haul himself higher, neck tendons standing out. A rising servo whine comes from the mechanical shoulder, then a grinding stutter. A short burst of small orange sparks spits out through the torn jacket, and a thin wisp of smoke curls from the joint. The steel plates jerk twice and lock rigid. End state: Elion's eyes snap wide toward his own shoulder, the shoulder frozen and smoking, chin still level with the pipe. [Stage 2 | 3-5 seconds] Continue from the previous stage: same close-up, same pipe and wall plate, left hand still clamped beside the plate. Primary event: The mechanical arm goes dead and falls away from the pipe. Elion's whole body drops in one hard jolt, his face sliding down out of frame below the pipe. His left hand stays clamped on the pipe as his full weight snaps onto it: the arm whips straight, the pipe dips and shudders, rust dust bursts off its surface. End state: Only Elion's left hand and straightened forearm remain in frame, locked on the pipe beside the wall plate. [Stage 3 | 5-8 seconds] Cut to a wide shot from out in the open shaft, level with the pipe, looking back at the right-hand wall. Primary event: Elion hangs by his left arm alone from the pipe beside the wall plate, a small figure against the vast concrete wall, legs dangling over the dark drop. His body swings out away from the wall and back in a slow pendulum arc. The mechanical arm hangs limp at his side, twitching once, a last spark falling and fading into the dark below. End state: The swing settles, Elion hanging one-armed, body turning slightly, the drop beneath him. [Stage 4 | 8-10 seconds] Cut to a close-up on Elion's left hand and forearm on the pipe, the wall plate at the right edge of frame. Primary event: The fingers are white at the knuckles, the forearm tendons trembling hard, the whole arm shaking under his weight. The fingers slide a few millimetres along the rusted surface, then clench and hold. End state: Elion's left hand still wrapped around the pipe, the arm visibly trembling, rust flakes drifting down past the frame. [Visual Style] Match the source video: 35mm film look, visible organic grain, natural lens softness toward the frame edges, neutral natural colour, grey concrete stays grey, rust stays brown. The sparks are the only warm, bright colour. Skin with real pores, sweat sheen, and grime. Motion blur on the drop. All action plays at real-time speed, with no slow motion. [Audio] Diegetic only: <Elion's strained breathing through clenched teeth>, <a rising mechanical servo whine>, <a harsh grinding stutter of gears>, <a sharp electrical crackle and spark hiss>, <a ragged cry as he drops>, <a hard metallic clang and groan as the pipe takes his full weight>, <the wall plate bolts creaking>, <rust flakes ticking down into the dark>, <fast, shaking breaths>, low hollow wind moving through the shaft. NO BGM. [Maintain Consistency] Keep Elion's identity, torn jacket, and mechanical right shoulder consistent with the source video. The mechanical arm stays limp after it fails. The left hand stays on the pipe beside the wall plate from Stage 2 to the end. The pipe extends from the wall plate on the right-hand wall, and the drop stays below throughout.
In the generator, choose Seedance 2.5 and attach one MP4 or MOV clip of 2 to 30 seconds, up to 200 MB and at least 480p. Only upload footage you have the right to use.
Start with “Extend the video by N seconds”. The word extend (or prolong, or the same verb in Chinese, Japanese, Korean, Spanish, Portuguese, German, French or Russian) switches the job to extend mode, and the composer shows a “Video extend” badge. Then describe the last frame and the next action.
Set 4 to 30 seconds of new footage and 480p, 720p or 1080p (1080p from Pro, Premium and credit packs; Lite goes up to 720p). The aspect ratio follows your clip. The composer shows the exact credit cost before you generate.
The result is the new segment only, starting on your clip’s last frame. Place it straight after the original in any editor; because the first frame matches, the join plays as one continuous shot.
Starter instruction (prefilled when you open the generator from here):
Extend the video forward by 5 seconds. Continue directly from the last frame with the same camera, lighting and sound, then [describe the next action].
Each task uses the current generator quote for its model, duration, resolution and references. Identical settings cost the same credits on every plan; subscriptions do not reduce the task credit charge.
| Job | 480p | 720p | 1080p |
|---|---|---|---|
| Per billed second | 2.12 | 4.58 | 10.21 |
| 5 s clip + 5 s new | 21 | 46 | 102 |
| 10 s clip + 10 s new | 42 | 92 | 204 |
| 10 s clip + 20 s new | 64 | 137 | 306 |
| 30 s clip + 30 s new | 127 | 275 | 613 |
Credits the generator charges on each plan today (plan discounts included, as a new subscriber), and the dollar value of those credits at the plan’s price per credit. Taxes not included.
| Plan | Billed amount | Credits | Price per credit |
|---|---|---|---|
| Lite 300 | $14.90/month | 300/month | $0.0497 |
| Lite 300 | $156.00/year | 300/month | $0.0433 |
| Pro 600 | $29.00/month | 600/month | $0.0483 |
| Pro 600 | $174.00/year | 600/month | $0.0242 |
| Pro 1300 | $59.00/month | 1300/month | $0.0454 |
| Pro 1300 | $598.80/year | 1300/month | $0.0384 |
| Pro 2000 | $89.00/month | 2000/month | $0.0445 |
| Pro 2000 | $828.00/year | 2000/month | $0.0345 |
| Premium 3500 | $149.00/month | 3500/month | $0.0426 |
| Premium 3500 | $1188.00/year | 3500/month | $0.0283 |
| Premium 5200 | $219.00/month | 5200/month | $0.0421 |
| Premium 5200 | $2028.00/year | 5200/month | $0.0325 |
| Premium 7200 | $299.00/month | 7200/month | $0.0415 |
| Premium 7200 | $2748.00/year | 7200/month | $0.0318 |
| Credit pack | $29.90 | 350 | $0.0854 |
| Credit pack | $49.90 | 600 | $0.0832 |
| Credit pack | $79.90 | 1000 | $0.0799 |
| Credit pack | $199.00 | 2500 | $0.0796 |
| Credit pack | $999.00 | 13000 | $0.0768 |
Annual plans are billed yearly. Starter credits are valid for 180 days; other standard packs for 365 days. Taxes and personal offers are shown in checkout.
Eligible new verified accounts may claim up to 5 welcome credits for 7 days after human verification, while the promotion budget is available. This can cover a low-cost image, not a guaranteed free video. New video generation requires sufficient purchased credits or eligible bounded unlimited capacity. See pricing for every plan and pack, or the AI video price index for the per-second rate of every model.
Seedance 2.5 generates the extension’s sound together with the picture, so footsteps, impacts, engine noise and room tone land on the frames that cause them. Describe the sound you want in the instruction, for example “diegetic sound only: strained breathing, a metallic clang, wind in the shaft, no music”, and it carries on from the source’s mood.
Spoken lines work too: put the words in quotes and name who says them. Switching audio off returns a silent clip for your own mix; the credit cost is the same either way. On Open AI Image, Seedance 2.0, Veo 3.1, Kling 3.0, Wan 3.0 and MiniMax H3 also generate sound in text-to-video and image-to-video, but only Seedance 2.5 extends an existing clip.
Open AI Image is an independent platform and is not affiliated with ByteDance or the other model providers named here. The example above is a customer’s generation on Open AI Image.