SiLVi: Simple Interface for Labeling Video Interactions

arXiv:2511.03819 · cs.CV, q-bio.QM · Submitted 2025-11-05 · Read on arXiv

Listen

Transcript

Introduction to the show: ident: AI Radio. Generated commentary on the latest Artificial Intelligence papers.

Tom: Hi, I'm Tom.

Jane: And I'm Jane, here with Lu, Meng and our in-house large language model, Lalam.

Tom: We're looking at the paper: "SiLVi: Simple Interface for Labeling Video Interactions".

Jane: Here's the gist of the paper. The gist: SiLVi is an open-source labeling software that integrates both behavioral labeling and localization for video data, enabling researchers to annotate actions and interactions directly within video data to generate structured outputs for training computer vision models.

Tom: Video recordings are an important tool in behavioral ecology, providing a non-invasive and scalable means to observe animal behavior over extended periods and across diverse environments that is more comprehensive than focal sampling Manual annotation of such videos has long been a cornerstone of behavioral analyses, allowing researchers to quantify complex behaviors that are difficult to capture in real time The growing availability of annotated, open-source datasets such as PanAf20k (Brookes et al.

Jane: 2024b), ChimpAct (Ma et al.

Tom: 2023), ChimpBehave (Fuchs et al.

Title and authors: Tom: Now, let’s look at what SiLVi actually does according to the paper. It presents this open-source labeling software that integrates both behavioral labeling and localization for video data.

Jane: So the summary says it takes video recordings—like those from camera traps or drones—and allows researchers to annotate actions and interactions directly within the video data to make structured outputs for training computer vision models.

Lu: The core problem they are tackling is that existing tools either label behavior without knowing where it is in space, or they localize without capturing the actual interaction over time.

Meng: So SiLVi fills that gap by supporting both spatial and temporal localization simultaneously, which lets you mark exactly *where* and *when* an interaction happens.

Tom: It supports common video formats like MP4 and WebM and includes a navigation system where you can load multiple videos of the same scene with different points of view.

Jane: In the main view, you can zoom in on regions of interest to detect precise boundaries, which is helpful for seeing exactly how an object or interaction is bounded within the frame.

Lu: The input mechanism relies on importing a tracking file, which can be in simplified or extended MOT Challenge format from Dendorfer et al. two thousand twenty <ref:2511.03819#pg1>.

Tom: The simplified format is a text file with one line per detection containing frame number, object ID, bounding box coordinates—with the top left corner of the bounding box—detection confidence and object class.

Jane: And the extended format adds individual ID and confidence, which you can then use to map those detections onto your video views.

Lu: They also allow users to upload a CSV file with individual names into a panel called Individuals, which automatically translates the object ID from the tracking file into the respective name.

Meng: If they have fewer than twenty-six individuals or actions in their dataset, the software automatically assigns keyboard shortcuts based on the alphabet for you.

Tom: And finally, they have interactive bounding boxes where you can click them or use those shortcuts to annotate interactions with a subject and a target.

Jane: The system creates a "Behaviors" panel that lists all annotated interactions and actions with their respective start and end times, letting you jump to the precise frame by clicking on those timestamps.

Lu: And they allow for fast corrections; you can apply corrections to an entire track, a track after a given frame, or just the current frame.

Tom: So the main point is that it’s a lightweight tool designed specifically to facilitate annotation in a spatially and temporally localized manner for generating training data.

Jane: It’s about taking messy video observation and turning it into clean, structured data that machine learning models can actually use to learn complex social patterns.

Lu: It’s about providing the necessary tools for high-quality behavioral annotation that moves beyond simple presence detection toward detailed interaction mapping within the video.

Meng: And from a practical standpoint, it solves the problem of having to manually coordinate multiple views and ensuring every frame is perfectly tagged with context.

The paper's summary: Tom: Moving on to the improvements they suggest for this SiLVi system. They focus heavily on how you can use these features to get better results from your computer vision models.

Jane: The main improvement they highlight is that automated annotation of spatiotemporal interactions lets computer vision models move beyond individual-centric behavioral models toward richer representations of social behavior.

Lu: This enables training models that capture complex dyadic or group dynamics by distinguishing between actions and interactions, such as "grooming" versus "being groomed," which is what they call it in their discussion.

Tom: That’s a big conceptual leap—it means the model isn't just looking for one thing; it’s looking at the relationship between two things.

Jane: They also discuss how generating structured outputs suitable for training and validating computer vision models allows researchers to automate parts of the annotation process, offering greater consistency and scalability when you’re dealing with large datasets.

Lu: This automation facilitates the development of automated approaches for fine-grained behavioral analyses by providing data with precise spatial and temporal localization.

Meng: For us at scale, that precision is what matters because it allows us to build more robust models that don't just guess based on fuzzy detections in a video stream.

Tom: The ability to correct tracking errors during annotation increases precision in observations, which means researchers can improve their tracking models by training them with higher-quality data.

Jane: This directly improves the robustness of downstream computer vision models that rely on accurate individual identification and spatial bounding boxes.

Lu: They also mention that they support the labeling of individual IDs and annotating or correcting tracks, which when integrated allows for the creation of high-fidelity datasets required for training deep learning models that depend on spatially localized input rather than just simple action detection.

Tom: So, SiLVi is essentially a system designed to handle the heavy lifting of turning video into this specific type of data structure.

Jane: And its flexibility supports annotation in diverse domains requiring fine-grained annotation, including human–computer interaction and clinical analysis, which is where it can really be useful.

Lu: The open-source nature enables developers to extend and adapt the application to meet specific requirements, which means it can be adapted for automated processing of large volumes of video data captured by camera traps or drones.

Meng: That adaptability is key; if we need a system that works on proprietary data streams, being able to customize the interface helps us get it there faster.

The paper's improvements: Tom: So we’ve covered how SiLVi works, from loading tracking files and annotating interactions in frames to exporting structured CSV data.

Jane: We’ve also discussed how this data structure is powerful for training models that look at the relationship between actions and interactions rather than just single actions.

Lu: The main point is that SiLVi provides the framework for creating high-fidelity datasets necessary for training deep learning models that depend on spatially localized input, which is what they call it in their discussion.

Meng: And from an engineering standpoint, the ability to correct errors during annotation to improve tracking models with better data is a significant practical gain in quality control.

Tom: It’s about getting high-quality input data into the system so that the downstream computer vision models have a better foundation to learn from.

Jane: Ultimately, this paper on SiLVi: Simple Interface for Labeling Video Interactions shows how we can use open-source tools to bridge the gap between observational research and machine learning needs.

Lu: It provides a standardized way to capture these complex social dynamics that were previously too ambiguous to model effectively with current methods.

Meng: If you look at it as a production tool, it’s an interface for manual labeling that makes the process scalable for specific use cases, which is what I think is important.

Tom: Exactly. It's not a magic solution, but a very precise tool that helps researchers build the data they need for more nuanced AI systems to learn from.

Jane: Thanks Tom and Lu and Meng for walking us through this paper on SiLVi: Simple Interface for Labeling Video Interactions today.

Lu: We look forward to seeing how this structured data is used in future research across various fields where fine-grained annotation matters.

Meng: I’m looking forward to seeing what kind of real-world data flows through systems built on this type of framework next.

Conclusion: Tom: So, to wrap up, SiLVi is this open-source software that lets you label video interactions both spatially and temporally, which is crucial for training computer vision models that understand social dynamics better than just simple action detection.

Jane: Exactly. It gives researchers the tools to go beyond just marking *something* happening and start marking *who* is doing *what* to *whom*, with precise timing in between.

Lu: What this does is allow for the creation of much richer representations of social behavior in AI, moving us closer to models that capture group dynamics instead of just individual movements.

Meng: It’s a good tool for getting high-quality data into a pipeline, but the real question for me is how much manual effort you need to keep it running efficiently at scale.

Lalam: I'm confident this approach will yield structured outputs that are much more useful than the loose labels we usually get from simple video annotation tools.

Tom: Yeah, the paper details how they handle tracking files and use bounding boxes interactively, which is a solid mechanism for getting that spatial localization.

Jane: And they show how you can jump to those exact frames using the start and end times listed in the behaviors panel, which makes it much more precise than just a general timestamp.

Lu: The ability to correct tracking errors directly during annotation means researchers can actually improve their underlying tracking models by feeding SiLVi higher-quality data.

Meng: If you want to deploy this, you need a robust way to generate those initial tracks because the software is designed for manual labeling and doesn't have built-in vision assistance right now.

Tom: Right, so it needs an external tool like PriMAT to generate those bounding boxes before you bring them into SiLVi for the interaction tagging itself.

Jane: And that’s exactly what they point out—it’s not a plug-and-play solution for everything yet, but it sets the standard for how we should structure interaction data.

Lu: The flexibility to export that tracking and identification data in CSV format means it fits into existing workflows pretty well.

Meng: It’s good that it saves the current state of the annotation automatically, because if you lose progress on a big video, you don't want to start over from scratch.

Tom: So, SiLVi is this simple interface for labeling video interactions that gives us a structured way to feed complex social data into computer vision training pipelines.

Jane: It’s a really practical step toward making AI models understand the nuances of how groups behave in video recordings.

Lu: Moving forward, the real test will be how many different interaction types we can reliably define and label with this level of spatial and temporal control.

Meng: I’m curious to see if people start using it for things outside of animal behavior, like human-computer interaction or sports analysis since they mention that flexibility.

Lalam: Based on the structure proposed in "SiLVi: Simple Interface for Labeling Video Interactions," the potential for generating high-fidelity datasets is very high.

Tom: That’s what we were talking about. It’s a solid piece of infrastructure for turning messy video into usable training data.

Jane: Next time, we're going to look at papers that tackle the visual side, like how vision-language models are actually learning to see three dee space and think in a world beyond just flat images.

Ozan Kanbertay, Richard Vogg, Elif Karakoc, Peter M. Kappeler, Claudia Fichtel, Alexander S. Ecker

Institute of Computer Science and Campus Institute Data Science, University of Göttingen · Behavioral Ecology & Sociobiology Unit, German Primate Center, Göttingen, Germany · Department of Sociobiology/Anthropology, University of Göttingen

cs.CV, q-bio.QM

Submitted: 2025-11-05

Updated: 2026-10-17

Comments: Documentation link updated, Linux version added

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

The gist: The gist: SiLVi is an open-source labeling software that integrates both behavioral labeling and localization for video data, enabling researchers to annotate actions and interactions directly within

Key concepts

Behavioral Labeling: This is the process of manually marking specific behaviors or interactions occurring in a video. SiLVi facilitates this by allowing annotators to click on bounding boxes or use shortcuts to tag subjects and targets, distinguishing between simple actions and complex social interactions.
Localization: Localization refers to pinpointing exactly where an event happens within a video frame. Unlike older tools that only mark when an interaction occurs over time, SiLVi allows users to draw precise bounding boxes around the spatial extent of an interaction or object.
Tracking File (MOT Format): A tracking file is a text file that provides information about objects in a video, such as frame numbers and bounding box coordinates. SiLVi imports these files to help annotators quickly identify individuals and their locations across different views of the video.
Interaction vs. Action: The tool distinguishes between actions (e.g., a subject performing an action) and interactions (e.g., a subject interacting with another). Interactions are annotated by specifying both a subject and a target, providing richer data for modeling social dynamics.

Summary

The gist: SiLVi is an open-source labeling software that integrates both behavioral labeling and localization for video data, enabling researchers to annotate actions and interactions directly within video data to generate structured outputs for training computer vision models.

Introduction

Video recordings are an important tool in behavioral ecology, providing a non-invasive and scalable means to observe animal behavior over extended periods and across diverse environments that is more comprehensive than focal sampling Manual annotation of such videos has long been a cornerstone of behavioral analyses, allowing researchers to quantify complex behaviors that are difficult to capture in real time The growing availability of annotated, open-source datasets such as PanAf20k (Brookes et al. 2024b), ChimpAct (Ma et al. 2023), ChimpBehave (Fuchs et al. 2025), and BaboonLand (Duporge et al. 2025) has enabled significant progress in the development of machine learning models for the automated detection of temporally and spatially localized actions in video data (Brookes et al. 2024a; Goss et al. 2024; Ma et al. 2024) > Nonetheless, many important behavioral phenomena, particularly interactions between individuals, remain difficult to model Current machine learning approaches for primate behavior typically decompose dyadic or group interactions into simultaneous individual actions, for example “grooming” and “being groomed” (Duporge et al. 2025; Ma et al. 2023) > For instance, when multiple grooming events occur simultaneously within a group, the pairwise associations become ambiguous One key obstacle to progress in this area is the lack of annotated datasets that explicitly capture interactions with spatial and temporal precision Although existing annotation tools such as BORIS (Friard et al. 2016) support the labeling of social behaviors, they typically do so in a non-localized manner, marking only the presence of an interaction over time rather than its spatial extent within the video frame This limitation prevents their use in training deep learning models that rely on spatially localized input

SiLVi Functionality and Design

SiLVi is a lightweight, open-source tool designed specifically to facilitate the annotation of interactions in a way that is both spatially and temporally localized, enabling the generation of training data for computer vision models It supports common video formats — including MP4 and WebM — and codecs Navigation allows users to load multiple video recordings of the same scene with different points of view, with the most important video loaded into “Main View” and additional views displayed side by side The main view enables users to zoom in on regions of interest, which can be helpful to detect precise boundaries of an object or detailed interactions Users can write free-form notes that will be saved with the video during the whole annotation process

User Input and Tracking Management

To create spatially localized annotations of interactions, a tracking file for the main video can be imported into the app The tracking file should either be in simplified or extended MOT Challenge format (Dendorfer et al. 2020) > The simplified format consists of a text file with one line per detection containing frame number, object ID, bounding box coordinates (with the top left corner of the bounding box, width and height), detection confidence and object class Alternatively, the extended format additionally includes individual ID and confidence Such a tracking file can be obtained by processing a video with a multi-animal tracking model such as PriMAT (Vogg et al. 2024) > Tracking files are displayed as bounding boxes, each with an object class and ID Users can upload a single CSV file with one individual name per line into the panel “Individuals” (Fig. 1, right) to automatically translate the individual ID from the tracking file into the respective name The ethogram can be uploaded with a CSV file into the panel “Ethogram” If the dataset contains fewer than 26 individuals or actions, the app automatically assigns keyboard shortcuts, one for each letter of the alphabet

Interaction Annotation and Correction

SiLVi makes the bounding boxes in the tracking file interactive for annotating interactions and actions Annotations can be done by either clicking on the bounding boxes or utilizing the customizable keyboard shortcuts assigned to subjects and items in the ethogram The difference between interactions and actions is that interactions are annotated with a subject and a target, while actions are directly tagged to a subject The “Behaviors” panel lists all annotated interactions and actions with respective start and end times, allowing users to jump to the precise frame by clicking on the start or end time of an interaction SiLVi allows for fast and easy corrections of different types of error (see Table 1) > Users can choose to apply corrections to an entire track, to a track after a given frame, or only to the current frame Tracks can optionally be annotated with individual IDs by right-clicking on a bounding box and selecting the individual’s name from a drop-down menu

Data Export and Application

Annotations for tracking, identification, action detection, as well as free-form notes for the video can be exported in CSV format Tracking and identification data are exported in the same format as they were input Identification files contain subject, (inter)action, target, start, end and duration of the interaction both in frames and in seconds SiLVi saves the current status of the annotation at all times and resumes at the current state of the annotation even after closing and restarting The interface is versatile for manual behavioral annotation, applicable to a wide range of video data beyond animal behavior research, including human–computer interaction, clinical and sports performance analysis, and social or educational research Currently, SiLVi is designed for manual interaction annotation and does not include built-in computer vision assistance Features such as automated bounding box proposals or individual identification must be generated externally using dedicated tools — e.g., PriMAT (Vogg et al. 2024) — and subsequently imported into SiLVi, as described in Section 2 The open-source nature of the codebase enables developers to extend and adapt the application to meet specific requirements This enables automated processing of large volumes of video data captured by camera traps, drones, or manual recording The interface is intentionally designed to be simple and intuitive, ensuring accessibility for annotators with diverse backgrounds

Discussion and Future Directions

Behavioral ecologists can use SiLVi to manually annotate behaviors in their video recordings Computer vision researchers can utilize the annotated bounding boxes, identification labels, actions, and interactions to train models for automated detection of behavior in both laboratory settings and the wild (Jiang et al. 2024; Liu et al. 2021; Ryan et al. 2025; Vogg et al.

Improvements for AI systems

Automated annotation of spatiotemporal interactions allows computer vision models to move beyond individual-centric behavioral models toward richer representations of social behavior. This enables training models that capture complex dyadic or group dynamics by distinguishing between actions and interactions, such as grooming versus being groomed.
Generation of structured outputs suitable for training and validating computer vision models allows researchers to automate parts of the annotation process, offering the possibility of greater consistency and scalability. This facilitates the development of automated approaches for fine-grained behavioral analyses by providing data with precise spatial and temporal localization.
The ability to correct tracking errors during annotation increases precision in observations and enables researchers to improve tracking models by training them with higher-quality data. This directly improves the robustness of downstream computer vision models that rely on accurate individual identification and spatial bounding boxes.
SiLVi supports the labeling of individual IDs and annotating or correcting tracks, which, when integrated, allows for the creation of high-fidelity datasets required for training deep learning models that depend on spatially localized input rather than just simple action detection.
The software's flexibility supports annotation in diverse domains requiring fine-grained annotation, including human–computer interaction and clinical analysis. This means the resulting computer vision systems can be adapted for analyzing complex social or educational research scenarios beyond animal behavior.