BYTEDANCE

Bytedance Seedance 1.5 Pro is an advanced text-to-video model designed to generate broadcast-ready video clips, complete with synchronized dialogue, sound effects, and music, all from a single text prompt. Utilizing a dual-branch diffusion transformer, Seedance 1.5 Pro renders video and audio in the same latent space, ensuring tightly synchronized lip movements and natural foley without the need for any post-production editing.

This model is ideal for producing short-form, high-quality video content for commercial use, social media platforms (such as TikTok, Reels, and YouTube Shorts), product ads, dramatic scenes, talking-head avatars, storyboards, previsualizations, and music videos. Seedance 1.5 Pro targets users seeking efficient and flexible video generation workflows—such as content creators, marketers, filmmakers, and teams in need of quick visual storytelling or preproduction assets.

Core Capabilities

Seedance 1.5 Pro excels at creating 4–12 second video clips (up to 12 seconds maximum), supporting resolutions up to 1080p at 24 frames per second with smooth temporal consistency. The model’s hallmark feature is native audio generation, which includes spoken dialogue, ambient sound, foley effects, and background music, all closely matched to the visual content. Lip-sync accuracy and audio-visual timing are maintained without manual adjustment.

The model delivers cinematic camera grammar—including pan, tilt, zoom, dolly, orbit, tracking shots, and rack focus—directly interpreted from the user’s text prompts. The model honors prompt instructions for camera style (e.g. “handheld with subtle shake”, “smooth orbit right”, or “locked tripod”) and can execute sophisticated motion dynamics in response. Camera position may be fixed or dynamic, as specified.

Character consistency is another key advantage: faces, wardrobe details, and expressions are preserved across frames and throughout a clip, even as the camera’s angle or distance changes. This stability supports multi-character storytelling and maintains visual narrative coherence. The model also manages emotional arcs, multi-character blocking, and logical scene progression.

Technical Details

• Input Modality: Text prompt (required), describing scene, action, dialogue, camera movements, and audio details
• Output Modality: Video (MP4 H.264), with audio encoded at 48 kHz AAC
• Supported output resolutions: 480p, 720p, and 1080p
• Aspect ratios supported: 21:9, 16:9 (default), 4:3, 1:1, 3:4, 9:16
• Clip duration: 4 to 12 seconds (default 5 seconds)
• Frame rate: Up to 24 fps
• Audio: Mixed dialogue, foley, and score by default; can be disabled for silent video
• Camera control: Option to fix the camera (tripod shot) or allow described movement
• Reproducibility: Accepts a random seed to allow deterministic outputs
• Safety: Optional safety checker may be enabled
• Start/end frame anchoring: When used for image-to-video, start and end frames can be set by uploading reference images; the model generates realistic dynamics and transitions between these anchors
• API access: Available through the fal.ai platform

Performance Characteristics

• Inference speed: Approximately 30–45 seconds to generate a 5-second video clip (precise time varies by hardware)
• Output format: MP4 (H.264), audio in AAC at 48 kHz

Limitations and Best Practices

• Clip length: Maximum video length supported is 12 seconds
• Resolution: Up to 1080p is supported; higher resolutions are not documented
• Prompt specificity: For best results, prompts should be specific and focused on one location and 1–2 main characters per clip
• Coherence: Keeping scenes concise and minimizing quick location/character changes improves narrative and visual consistency
• Start/end frames: Only applicable for image-to-video workflows; not part of default text-to-video usage
• Motion realism: The model generates physics-aware movement, not merely interpolated frames, supporting dynamic camera and character actions

Ideal Use Cases

• Short-form drama with dialogue and emotion
• Advertisement spots with synchronized voice-overs
• Social media teasers and trailers packed with tension, music, and design
• Animated product hero shots—demos or reveals
• Realistic talking-head avatars for explainer content or virtual hosts
• Storyboarding or previsualization for fast scene iteration
• Synchronized visuals and audio for music or lyric videos

Bytedance Seedance 1.5 Pro stands out for its tight integration of audio and video, cinematic expression, character consistency, and efficient creation of high-quality, emotionally resonant short video content.