Tech Tips

Sunday, November 19, 2023

DICOM Image Caching with Redis

Summary

This post covers a demonstration of the usage of Redis for caching DICOM imagery. I use a Jupyter Notebook to step through loading and searching DICOM images in a Redis Enterprise environment.

Architecture

Redis Enterprise Environment

Screen-shot below of the resulting environment in Docker.

Sample DICOM Image

I use a portion of sample images included with the Pydicom lib. Below is an example:

Code Snippets

Data Load

The code below loops through the Pydicom-included DICOM files. Those that contain the meta-data that is going to be subsequently used for some search scenarios are broken up into 5 KB chunks and stored as Redis Strings. Those chunks and the meta-data are then saved to a Redis JSON object. The chunks' Redis key names are stored as an array in that JSON object.

Search Scenario 1

This code retrieves all the byte chunks for a DICOM image where the Redis key is known. Strictly, speaking this isn't a 'search'. I'm simply performing a JSON GET for a key name.

Search Scenario 2

The code below demonstrates how to put together a Redis Search on the image meta-data. In this case, we're looking for a DICOM image with a protocolName of 194 and studyDate in 2019.

Source

https://github.com/Redislabs-Solution-Architects/redis-dicom

Sunday, November 5, 2023

Redis Vector Database Sizing Tool

Summary

In this post, I cover a utility I wrote for observing Redis vector data and index sizes with varying data types and index parameters. The tool creates a single-node, single-shard Redis Enterprise database with the Search and JSON modules enabled.

Code Snippets

Constants and Enums

Redis Index Build and Data Load

Sample Results

Source

https://github.com/Redislabs-Solution-Architects/vss-sizer

Redis Search - Rental Availability

Summary

This post covers a very specific use case of Redis in the short-term rental domain. Specifically, Redis is used to find property availability in a given geographic area and date/time slot.

Architecture

Code Snippets

Data Load

The code below loads rental properties as Redis JSON objects and US Postal ZIP codes with their associated lat/longs as Redis strings.

Property Search

The code below represents an Expressjs route for performing searches on the Redis properties. The search is performed on rental property type and geographic distance from a given location.

Source

https://github.com/Redislabs-Solution-Architects/rental-availability

Monday, May 29, 2023

OpenAI Q&A using Redis VSS for Context

Summary

I'll be covering the use case of providing supplemental context to OpenAI in a question/answer scenario (ChatGPT). Various news articles will be vectorized and stored in Redis. For a given question that lies outside of ChatGPT's knowledge, additional context will be fetched from Redis via Vector Similarity Search (VSS). That context will aid ChatGPT in providing a more accurate answer.

Architecture

Code Snippets

OpenAI Prompt/Collect Helper Function

The code below is a simple function for sending a prompt into ChatGPT and then extracting the resulting response.

OpenAI QnA Example 1

The prompt below is on a topic (FTX meltdown) that is outside of ChatGPT's training cut-off date. As a result, the response is of poor quality (wrong).

Redis Context Index Build

The code below uses Redis-py client lib to build an index for business article content in Redis. The index has two fields in its schema: the text content itself and a vector representing the embedding of that text content.

Context Storage as Redis JSON

The code below loads up a dozen different business articles into Redis as JSON objects.

RedisInsight

Redis Vector Search (KNN)

A vector search in Redis is depicted below. This particular query picks the #1 article as far as vector distance to a given question (prompt).

Reprompt ChatGPT with Redis-fetched Context

The context fetched in the previous step is now added as supplemental info to ChatGPT for the same FTX-related question. The response is now in line with expectations.

Source

https://github.com/openai/openai-cookbook/tree/main/examples/vector_databases/redis/redisqna

OpenAI + Redis VSS w/JSON

Summary

This post will cover an example of how to use Redis Vector Similarity Search (VSS) capabilities with OpenAI as the embedding engine. Documents will be stored as JSON objects within Redis and then searched via VSS via KNN and Hybrid queries.

Architecture

Code Snippets

OpenAI Embedding

Redis Index Creation

Redis JSON Document Insertion

RedisInsight

Redis Semantic Search (KNN)

Redis Hybrid Search (Full-text + KNN)

Source

https://github.com/openai/openai-cookbook/tree/main/examples/vector_databases/redis/redisjson

Saturday, May 27, 2023

Redis Polygon Search

Summary

This post will demonstrate the usage of a new search feature within Redis - geospatial search with polygons. This search feature is part of the 7.2.0-M01 Redis Stack release. This initial release supports the WITHIN and CONTAINS query types for polygons, only. Additional geospatial search types will be forthcoming in future releases.

Architecture

Code Snippets

Point Generation

I use the Shapely module to generate the geometries for this demo. The code snippet below will generate a random point, optionally within a bounding box.

Polygon Generation

Random polygons can be generated using the random point function above. By passing a polygon as an input parameter, the generated polygon can be placed inside that input polygon.

Redis Polygon Search Index

The command below creates an index on the polygons with the new keyword 'GEOMETRY' for their associated WKT-formatted points. Note this code is sending a raw CLI command to Redis. The redis-py lib does not support the new geospatial command sets at the time of this writing.

Redis Polygon Load as JSON

The code below inserts 4 polygons into Redis as JSON objects. Those objects are indexed within Redis by the code above.

Redis Polygon Search

Redis Polygon search (contains or within) code below. Again, this is the raw CLI command.

Results

Plot

Results

Source

https://github.com/Redislabs-Solution-Architects/polygon-demo

Sunday, April 23, 2023

Redis Document/Search - Java Examples

Summary

This post will provide some snippets from Redis Query Workshop available on GitHub. That workshop covers parallel examples in CLI, Python, Nodejs, Java, and C#. This post will focus on Java examples.

Basic JSON

Basic Search

Advanced JSON

Advanced Search

Source

https://github.com/Redislabs-Solution-Architects/Specialist-Solution-Workshops/tree/main/Real-Time-Query-Workshop/java