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KlingAvatar 2.0 Technical Report
Kling Team, Jialu Chen, Yikang Ding, Zhixue Fang, Kun Gai, Yuan Gao, Kang He, Jingyun Hua, Boyuan Jiang, Mingming Lao, Xiaohan Li, Hui Liu, Jiwen Liu, Xiaoqiang Liu, Yuan Liu, Shun Lu, Yongsen Mao, Yingchao Shao, Huafeng Shi, Xiaoyu Shi, Peiqin Sun, Songlin Tang, Pengfei Wan, Chao Wang, Xuebo Wang, Haoxian Zhang, Yuanxing Zhang, Yan Zhou
TL;DR
Prior methods for long-duration, high-resolution avatar videos remain inefficient and can lose visual quality and coherence with complex multimodal instructions. KlingAvatar 2.0 combines spatio-temporal cascades with co-reasoning directors, and the authors report state-of-the-art performance across multiple video-generation dimensions.
Problem
Prior methods remain inefficient for long-duration, high-resolution avatar videos and show limited coherence with complex, long-horizon multimodal instructions.
Source: §1 · pp. 1–2Method
KlingAvatar 2.0 combines progressive spatial-temporal cascades for long-form, high-resolution synthesis with co-reasoning directors that plan storylines and refine instruction following.
Source: §1 · p. 3Results
The authors report state-of-the-art performance across visual quality, character animation, camera movement, lip synchronization, audio-emotion alignment, and generalization to diverse domains.
Source: §1 · p. 3Takeaways & Limitations
The integrated system advances audio-driven avatar synthesis while addressing efficiency, instruction alignment, and multi-character coordination.
Source: §1 · p. 3
Abstract
from arXiv · showhide
Avatar video generation models have achieved remarkable progress in recent years. However, prior work exhibits limited efficiency in generating long-duration high-resolution videos, suffering from temporal drifting, quality degradation, and weak prompt following as video length increases. To address these challenges, we propose KlingAvatar 2.0, a spatio-temporal cascade framework that performs upscaling in both spatial resolution and temporal dimension. The framework first generates low-resolution blueprint video keyframes that capture global semantics and motion, and then refines them into high-resolution, temporally coherent sub-clips using a first-last frame strategy, while retaining smooth temporal transitions in long-form videos. To enhance cross-modal instruction fusion and alignment in extended videos, we introduce a Co-Reasoning Director composed of three modality-specific large language model (LLM) experts. These experts reason about modality priorities and infer underlying user intent, converting inputs into detailed storylines through multi-turn dialogue. A Negative Director further refines negative prompts to improve instruction alignment. Building on these components, we extend the framework to support ID-specific multi-character control. Extensive experiments demonstrate that our model effectively addresses the challenges of efficient, multimodally aligned long-form high-resolution video generation, delivering enhanced visual clarity, realistic lip-teeth rendering with accurate lip synchronization, strong identity preservation, and coherent multimodal instruction following.
1 Introduction
Audio-driven avatar generation still struggles with efficient long-duration, high-resolution video and coherent adherence to complex multimodal instructions. KlingAvatar 2.0 combines spatial-temporal upscaling, multimodal instruction reasoning, and identity-specific multi-character control to address these challenges.
- The expanded training dataset contains high-quality cinematic videos, multilingual and multi-character conversations, and filtering for visual fidelity and consistent audio-lip synchronization.It expands upon [13].Source: §1 · p. 3
- The spatial-temporal cascade progressively and in parallel upsamples low-resolution blueprint videos in time and space, improving efficiency and detail while mitigating temporal drift.The framework supports long-duration, high-resolution generation.Source: §1 · pp. 2–3
- A Co-Reasoning Director coordinates multiple MLLMs and LLMs through multi-turn dialogue to resolve modality conflicts and create shot-level storylines, while a Negative Director refines negative prompts.The negative director is intended to improve instruction following and character emotion expression.Source: §1 · pp. 2–3
- Deep DiT features support character-mask prediction and mask-controlled audio injection, enabling synchronized yet individually controlled animations from multiple audio streams.This mechanism targets complex multi-character conversational settings.Source: §1 · pp. 2–3
- KlingAvatar 2.0 reports state-of-the-art performance across visual quality, character animation, camera movement, lip synchronization, and audio-emotion alignment, with efficient, coherent videos up to 5 minutes.The reported comparisons include leading competitors [13] [30].Source: §1 · p. 3
2 Related Works
Related work traces diffusion-based video generation toward temporally compressed, high-resolution systems, alongside the evolution of avatar synthesis from motion transfer to audio-driven generation. General video models still lack audio conditioning, while avatar research increasingly adds richer motion, interaction, and multimodal planning.
Video Generation
- Video generation moved from temporalized U-Net diffusion [45] toward compressed-token DiT models [36] [38] [56] [67] [74], but still faces scalability, temporal-drift, and audio-conditioning limitations.Extensions address efficient long-context generation [7] [18] [32] [53] [70] [73], cascaded high-resolution synthesis [52], and world modeling [26] [51] [69]; general video methods remain inadequate for speech-driven digital humans.Source: §2 · p. 3
Multimodal Avatar Synthesis
- Avatar synthesis progressed from reference-video or landmark motion transfer [24] [42] [46] [47] [61] [72] and 3D methods [11] [25] to audio-driven generation.Audio-driven systems use explicit facial landmarks [8] [28] [57], implicit motion representations [19] [21] [71], or end-to-end cross-attention diffusion [29] [41] [55] [64] [65] [75]; semi-body methods synchronize gestures and upper-body movement [39] [54].Source: §2 · pp. 3–4
- Pretrained video diffusion improves avatar temporal coherence and visual fidelity [9] [10] [15] [16] [17] [35] [60], while extensions address human-object interaction [27] and multi-person audio control [33] [62] [63].These approaches support complex backgrounds, full-body interactions, and per-character audio control.Source: §2 · p. 4
- MLLM-based multimodal planning uses shot-level guidance for long-duration generation, enabling fine-grained expression, vivid emotions, reasoned actions, and environmental interaction [13] [30].This line of work extends avatar generation through multimodal planning.Source: §2 · p. 4
3 Method
KlingAvatar 2.0 extends Kling-Avatar [13] to generate long-form avatar videos from reference images, audio, and text. Its method combines cascaded spatial-temporal refinement, multimodal storyline planning, identity-specific multi-character control, and inference acceleration.
3.1 Spatial-Temporal Cascade Modeling
- A two-stage spatial-temporal cascade plans global video dynamics with low-resolution keyframes, then refines them into high-resolution, audio-synchronized clips with coherent transitions.High-resolution keyframes anchor clip expansion, while audio-aware interpolation and super-resolution improve temporal connectivity, lip synchronization, spatial consistency, and visual detail.Source: §3.1 · pp. 4–5
3.2 Co-Reasoning Director
- Three Co-Reasoning Director experts analyze audio, reference-image context, and text instructions through dialogue, resolving conflicts and producing storyline and segment-level plans.The Negative Director down-weights implausible poses, artifacts, opposing emotions, and motion styles; audio-aligned segment plans parameterize keyframe and clip refinement.Source: §3.2 · p. 5
3.3 Multi-Character Control
- For multi-character scenes, deep DiT features predict per-character masks that gate identity-specific audio injection to corresponding regions, following character-aware audio-injection work [33] [62] [63].An automated annotation pipeline uses YOLO detection, DWPose keypoints, and SAM2 segmentation and tracking, then filters misaligned masks for training.Source: §3.3 · pp. 5–6
3.4 Accelerated Video Generation
- For faster inference, KlingAvatar 2.0 selects trajectory-preserving distillation over PCM [58] and DCM [37] or distribution-matching DMD [68], with customized schedulers and multitask distillation.The schedulers balance speedup against performance, and the report states that multitask configurations improve outcomes across individual tasks.Source: §3.4 · p. 6
4 Experiments
Human-preference evaluations show strong overall performance, particularly in motion expressiveness and text relevance, alongside coherent multimodal generation across complex scenarios and improved control of undesired content.
4.1 Experimental Setup
- Evaluation used 300 paired image, audio, and text cases—100 each of Chinese speech, English speech, and singing—with human GSB comparisons scored by (G+S)/(B+S).The protocol follows human-preference evaluation in [13]; higher scores indicate stronger human preference.Source: §4.1 · p. 7
- The extended GSB criteria assess face–lip synchronization, visual quality, motion plausibility and expressiveness, and text relevance.They cover synchronization and facial continuity, appearance and artifacts, coherent body/head/camera movement and tracking, expressive audio/text-matched gestures, and storyline, camera, and scene alignment with instructions.Source: §4.1 · pp. 7–8
4.2 Experimental Results
- KlingAvatar 2.0 shows strong overall GSB performance against HeyGen, Kling-Avatar [13], and OmniHuman-1.5 [30], with notable gains in motion expressiveness and text relevance.Quantitative results are summarized in Table 1 and visualized in Fig. 4.Source: §4.2 · p. 8
- KlingAvatar 2.0 produces more plausible hair motion and head poses, prompt-aligned camera movement, and expressive, audio-synchronized gestures and emotions.Comparisons describe baseline limitations in hair dynamics, camera instruction following, and folding hands in front of the chest.Source: §4.2 · p. 8
- Across diverse scenarios, the framework fuses image, audio, and text instructions into expressive characters, coherent body and camera motion, and precise lip synchronization, including multi-person interactions with per-character audio.These examples are presented as evidence of robustness and versatility in open, complex settings.Source: §4.2 · p. 8
- The negative director uses shot-specific prompts tied to storyline and target emotion, discouraging implausible expressions, unstable motion, and narrative-inconsistent artifacts.This contrasts with prior work's small, fixed set of generic negative prompts for an entire video.Source: §4.2 · p. 8
5 Conclusion
KlingAvatar 2.0 combines spatio-temporal cascade generation with multimodal co-reasoning to synthesize high-resolution, long-duration avatar videos. The framework also supports identity-specific multi-character audio control and uses an automated pipeline to curate multi-person video datasets.
5 Conclusion
- Experiments demonstrate leading performance in visual fidelity, identity preservation, lip–audio synchronization, instruction-following, long-duration coherence, and multi-character, multi-audio controllability.The report identifies these as the framework's experimental strengths.Source: §5 · p. 8
- Multimodal experts reason across audio cues, visual contexts, and complex instructions in multi-turn dialogues to resolve conflicts and produce global storylines and local sub-clip prompts.Storylines guide low-resolution blueprint keyframes, while local prompts refine sub-clip dynamics.Source: §5 · p. 8
- The framework upscales blueprint keyframes into high-resolution, audio-synchronized sub-clips and composes long-form videos in parallel using first–last frame conditioning.Source: §5 · p. 8
- KlingAvatar 2.0 extends generation to multi-character settings with identity-specific audio control and develops an automated annotation pipeline for large-scale multi-person video datasets.Source: §5 · p. 8