1Stanford University2Massachusetts Institute of Technology3Peking University4University of California, Berkeley5ByteDance✦Project lead & corresponding author
When an object leaves the frame,does the same object reappear?
In autoregressive long-video generation models
When an object leaves the frame,does the same object reappear?
Baseline2×
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01
Eye & brow
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Ear
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Memory capacity
How can we extend the effective context?
How can we extend the effective context?
02
Precise utilization
How can we precisely utilize long-range context?
01
Sliding Window
Limited context window.
Sliding window
02
Packed Context
Distant history is progressively coarsened.
•••
Packed Context
Existing Methods
High noiseGlobal structure
Low noiseFine detail
High-noise phase
Determines global semantic structure and motion dynamics.
Low-noise phase
Refines high-frequency textures, edges, and local details.
High-noise branch
Preserve temporal continuity while coarsening spatial detail.
HistoryLimited context
Context window
↓Temporal continuity · spatial coarsening
Compressed historyFull-history context
Context window
The context window now covers the full temporal span.
Low-noise branch
Preserve spatial detail through rotating sparse views.
HistoryLimited context
Context window
↻Cyclic shift across denoising timesteps
Rotating detail viewFull-history coverage
Context window
Rotating offsets recover detail across the entire history.
The diffusion timestep selects how history is compressed.
High noiseLow noise
Global history
Higher temporal densitySpatially coarse
Detail history
Spatially detailedTemporally sparse + rotating
Full historical coverage within a fixed token budget.
01
Memory capacity
✓ Solved
How can we extend theeffective context?
02
Precise utilization
How can we preciselyutilize long-range context?
Context Window
Context Window
Attention weight
Context WindowFirst frameHidden GTAdjacent frames
→Prediction×Retrieval failed
Long-video datasets
Adjacent frames are usually enough to predict what comes next.
Forward+Reverse
Reverse + forward
Reverse + forward turns any video into a loop.
Target FramesHidden GTHistory InputTarget
Shortcut
Crop
Shortcut removed.
Synthetic historyReversed videoDrop with probability pdrop
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↻Clickany video to compare frames
1sgap
FramePackLongLiveLongCat-VideoRing Forcing
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5sgap
FramePackLongLiveLongCat-VideoRing Forcing
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15sgap
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30sgap
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60sgap
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1 minute
Speed
PromptA dynamic tour through an art gallery filled with paintings, sculptures, and installations in diverse styles. Visitors move gracefully through the modern, naturally lit space while wide shots, close-ups, and sweeping camera moves reveal the works and the flow of the gallery.
PromptA close-up 3D animated scene of a short, fluffy monster kneeling beside a melting red candle. Its large eyes and open mouth gaze at the flame with wonder and curiosity. Warm dramatic light reveals every detail of its gentle expression inside a cozy room.
PromptA cinematic, grainy view of a white and orange tabby cat joyfully darting through a dense garden as if chasing something. The ground-level camera follows the narrow path through leaves and flowers while warm daylight catches the cat’s orange fur.
PromptA realistic archaeological excavation in a vast desert, where archaeologists carefully uncover a worn plastic chair buried beneath layers of sand. The setting sun casts long shadows across the dunes as a close, low camera angle emphasizes their detailed work.
PromptA highly detailed close-up in HD, focusing on dew droplets glistening on the delicate petals of a blue rose. Soft velvety petals, intricate patterns, and subtle gradients remain crisp against a blurred background as each droplet catches the light.
PromptA Chinese boy wearing glasses sits in a fast food restaurant, enjoying a cheeseburger with his eyes closed. He holds it with both hands and takes a big bite while warm, inviting light captures the joyful moment from a slightly low close-up angle.
PromptA student with thick-rimmed glasses walks through a classic university library corridor, hugging books and looking up in wonder at the high shelves. Rhythmic sunlight crosses his face as he moves through the deep, quiet space.
PromptAn older Chinese man sits at a warmly lit table and eats a bowl of noodles. The camera stays close to his expressive face and natural hand movements as steam rises through the intimate restaurant atmosphere.
PromptA woman in a flowing red dress walks through a luminous city street at night. The camera tracks her through saturated neon reflections, passing traffic, and shifting crowds while preserving her identity and movement over time.
