VideoDB Documentation

VideoDB Documentation

Scene Index Guide

Advanced Visual Search Pipelines

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Let's deep dive into Scene and Frame objects

Scene

A Scene object describes a unique event in the video. From a timeline perspective it’s a timestamp range.

video_id : id of the video object

start : seconds

end : seconds

description : string description

Each scene object has an attribute frames, that has list of Frame objects.

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Frame

Each Scene can be described by a list of frames. Each Frame object primarily has the URL of the image and its description field.

id : ID of the frame object

url : URL of the image

frame_time : Timestamp of the frame in the video

description : string description

video_id : id of the video object

scene_id : id of the scene object

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Screenshot 2024-07-04 at 11.41.39 AM.jpg

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We provide you with easy-to-use Objects and Functions to bring flexibility in designing your visual understanding pipeline. With these tools, you have the freedom to:

Extract scene according to your use case.

Go to frame level abstraction.

Assign label, custom model description for each frame.

Use of multiple models, prompts for each scene or frame to convert information to text.

Send multiple frames to vision model for better temporal activity understanding.

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extract_scenes()

This function accepts the extraction_type and extraction_config and returns a

SceneCollection⁠

object, which keep information about all the extracted scene lists.

Checkout

Scene Extraction Algorithms⁠

for more details.

scene_collection = video.extract_scenes(

extraction_type=SceneExtractionType.time_based,

extraction_config={"time": 30, "select_frames": ["middle"]},

)

Capture Temporal Change

Vision models excel at describing images, but videos present an added complexity due to the temporal changes in the information. With our pipeline, you can maintain image-level understanding in frames and combine them using LLMs at the scene level to capture temporal or activity-related understanding.

You have freedom to iterate through each scene and frame level to describe the information for indexing purposes.

Get scene collection

scene_collection = video.get_scene_collection("scene_collection_id")

Iterate through each scene and frame

Iterate over scenes and frames and attach description coming from external pipeline be it custom CV pipeline or custom model descriptions.

print("This is scene collection id", scene_collection.id)

print("This is scene collection config", scene_collection.config)

# get scene from collection

scenes = scene_collection.scenes

# Iterate through each scene

for scene in scenes:

print(f"Scene Duration {scene.start}-{scene.end}")

# Iterate through each frame in the scene

for frame in scene.frames:

print(f"Frame at {frame.frame_time} {frame.url}")

frame.description = "bring text from external sources/ pipeline"

)

Create Scene by custom annotation

These annotations can come from your application or from external vision model, if you extract the description using any vision LLM

for scene in scenes:

scene.description = "summary of frame level description"

Using this pipeline, you have the freedom to design your own flow. In the example above, we’ve described each frame in the scene independently, but some vision models allow multiple images in one go as well. Feel free to customise your flow as per your needs.

Experiment with sending multiple frames to a vision model.

Utilize prompts to describe multiple frames, then assign these descriptions to the scene.

Integrate your own vision model into the pipeline.

We’ll soon be adding more details and strategies for effective and advanced multimodal search. We welcome your input on what strategies have worked best in your specific use cases

Here’s our 🎙️

Discord⁠

channel where we brainstorm about such ideas.

Once you have a description of each scene in place, you can index and search for the information using the following functions.

from videodb import IndexType

#create new index and assign a name to it

index_id = video.index_scenes(scenes=scenes, name="My Custom Model")

# search using the index_id

res = video.search(query="first 29 sec",

index_type=IndexType.scene,

index_id=index_id)

res.play()