Evaluating Long-Form Video Comprehension with 1,500+ Expert-Annotated Samples
Built a multi-layered dataset of long-video annotation tasks, including complex edge cases such as STEM tutorials, multi-speaker dialogues, and audio-visual synchrony for benchmarking state-of-the-art (SOTA) video understanding models.
1,500+
annotated video tasks covering open-domain and instructional content.
500+
tasks with audio components, including speaker IDs, transcripts, and ambient sound labels.
100%
human-audited segmentation, with dual-pass QA for scene boundaries, caption accuracy, and visual tag coverage.

The Challenge
Multimodal agents often struggle with long-form video inputs due to unclear scene transitions, mixed audio-visual signals, or dense motion patterns. The client required a dataset that could:
- Evaluate scene segmentation, audio captioning, and transcript extraction with high temporal resolution
- Capture foreground motion, camera movement, visual text, and causal relationships
- Handle STEM domains requiring instructional focus such as math lectures, science experiments, and engineering tutorials
- Provide a clear reference for agentic evaluation, especially in videos with overlapping sounds, slides, or background distractions
The Approach
Dataset design
Each task consisted of:
- Global overview for visual and audio context, capturing setting, tone, and speaker structure
- Context-level segments annotated for overall scene structure and flow
- Fine-grained segments capturing semantically rich content and moment-specific interactions
Each video was annotated using context-level segmentation for scene structure and fine-grained segmentation for semantically rich moments.
Segment-level annotations:
- visual_caption: detailed description using the watch → observe → note → draft process
- visual_text: on-screen text reproduction with exact spelling and timestamps
- audio_caption: description of ambient audio, speaker tone, or key non-speech sound
- transcription: verbatim, timestamped speech with speaker IDs and character descriptions
All STEM-related videos were annotated to prioritize foreground instructional content and minimize focus on trivial background details.
Annotation and QA flow
- Annotators used Turing’s labeling tool integrated with LLM-based preannotation for visual captioning and transcription support
- 75+ annotators were trained through a structured bootcamp covering segmentation, narrative clarity, and STEM-specific guidelines
- Implemented dual-layer manual QA to review every sample:
- Layer 1: scene accuracy, audio-visual alignment, object detail
- Layer 2: grammar, label correctness, and metadata compliance - Programmatic checks were incorporated for segmentation consistency & hygiene, visual text extraction accuracy, and tag correctness.
The annotation and review guidelines enforced consistent tone, LaTeX formatting for math, timestamp fidelity, and a high level of accuracy across all tasks.
Key Results
- Delivered more than 1,500 long-video tasks, each with segment-aligned captions, tags, and QA metadata
- More than 500 videos contained audio, with structured transcripts and speaker labeling
- More than 250 STEM videos captured causal reasoning, step-by-step instruction, and multimodal synthesis
- Achieved 100% human-audited segmentation, with dual-pass QA for scene boundaries, caption accuracy, and visual tag coverage
- Achieved consistent tagging coverage across motion, scene, visual text, audio, and camera movement
The Outcome
The resulting dataset gave researchers a fine-grained tool to benchmark video models on:
- Long-form video coherence
- Instructional fidelity in STEM settings
- Audio-visual reasoning and transcript precision
- Agentic evaluation with multi-turn, multimodal supervision
The client appreciated the annotation quality, LLM-assisted tooling, and guideline compliance.
Want to evaluate your model’s long-video comprehension?
Request a labeled task with context-level and fine-grained segmentation, visual and audio captioning, transcripts with speaker IDs, and STEM reasoning metadata.
Request SampleFAQ
What’s in a sample task?
Each sample task contains a fully segmented video with overview captions, clip-level tags, transcripts, and visual and audio annotations.
Do you support STEM and multi-speaker formats?
Yes. We delivered more than 250 STEM videos and many others with multi-speaker speech and overlapping dialogue.
Is this dataset suitable for LLM or agent evaluation?
Yes. It was purpose-built to test grounding, reasoning, and long-context alignment.
Are LaTeX and technical formatting supported?
Yes. Math captions use LaTeX and are formatted for scientific evaluation.
What’s the NDA process?
A standard mutual NDA. Turing provides the countersigned agreement within one business day.
How fast can I get a sample?
Within three business days after NDA execution.
How well does your model handle dense, real-world videos?
Request an annotated task featuring overlapping speakers, technical diagrams, and context-level segment structure.
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