OCR plugin
The OCR plugin is a docker image that can be deployed using the following infrastructure prerequisites.
Infrastructure Prerequisites:
- S3 bucket or alternative (for example, minio)
- Kafka cluster
Starting with ocr-plugin 1.X it no longer requires RabbitMQ.
The following environment from previous releases must be removed in order to use OCR plugin: CELERY_BROKER_URL.
Deployment/Configuration
To deploy the OCR plugin, you will need to deploy ocr-plugin helm chart with custom values file.
Most important sections are these, but more can be extracted from helm chart.
image:
repository: <repository>/ocr-plugin
applicationSecrets: {}
replicaCount: 2
resources: {}
env: []
Credentials
S3 bucket:
applicationSecrets:
enable: true
envSecretKeyRef:
STORAGE_S3_ACCESS_KEY: access-key # default empty
STORAGE_S3_SECRET_KEY: secret-key # default empty
existingSecret: true
secretName: ocr-plugin-application-config
Kafka configuration
You can override the following environment variables:
| Environment Variable | Definition | Default Value | Example |
|---|---|---|---|
ENABLE_KAFKA_SASL | Indicates whether Kafka SASL authentication is enabled | False | - |
KAFKA_ADDRESS | The address of the Kafka bootstrap server in the format <hostname>:<port> | - | kafka-server1:9092 |
KAFKA_CONSUME_SCHEDULE | The interval (in seconds) at which Kafka messages are consumed | 30 | - |
KAFKA_INPUT_TOPIC | The Kafka topic from which input messages are consumed | - | - |
KAFKA_OCR_CONSUMER_GROUPID | The consumer group ID for the OCR Kafka consumer | ocr_group | - |
KAFKA_CONSUMER_AUTO_COMMIT | Determines whether Kafka consumer commits offsets automatically | True | - |
KAFKA_CONSUMER_AUTO_COMMIT_INTERVAL | The interval (in milliseconds) at which Kafka consumer commits offsets automatically | 1000 | - |
KAFKA_CONSUMER_TIMEOUT | The timeout (in milliseconds) for Kafka consumer operations | 28000 | - |
KAFKA_CONSUMER_MAX_POLL_INTERVAL | The maximum interval (in milliseconds) between consecutive polls for Kafka consume | 25000 | - |
KAFKA_CONSUMER_AUTO_OFFSET_RESET | The strategy for resetting the offset when no initial offset is available or if the current offset is invalid | earliest | - |
KAFKA_OUTPUT_TOPIC | The Kafka topic to which output messages are sent | - | - |
Please note that the default values and examples provided here are for illustrative purposes. Make sure to replace them with the appropriate values based on your Kafka configuration.
When configuring the OCR plugin, make sure to use the correct outgoing topic names that match the pattern expected by the Engine, which listens for messages on topics with specific names.
Authorization
You can override the following environment variables:
| Environment Variable | Definition | Default Value | Example |
|---|---|---|---|
OAUTH_CLIENT_ID | The client ID for OAuth authentication | - | your_client_id |
OAUTH_CLIENT_SECRET | The client secret for OAuth authentication | - | your_client_secret |
OAUTH_TOKEN_ENDPOINT_URI | The URI of the token endpoint for OAuth authentication | - | https://oauth.example.com/token |
Please note that the default values and examples provided here are for illustrative purposes. Make sure to replace them with the appropriate values based on your OAuth authentication configuration.
Storage (S3 configuration)
You can override the following environment variables:
| Environment Variable | Definition | Default Value | Example |
|---|---|---|---|
STORAGE_S3_HOST | The host address of the S3 storage service | - | minio:9000, https://s3.eu-west-1.amazonaws.com/ |
STORAGE_S3_SECURE_CONNECTION | Indicates whether to use a secure connection (HTTPS) for S3 storage | False | |
STORAGE_S3_LOCATION | The location of the S3 storage service | - | eu-west-1 |
STORAGE_S3_OCR_SCANS_BUCKET | The name of the S3 bucket for storing OCR scans | - | pdf-scans |
STORAGE_S3_OCR_SIGNATURE_BUCKET | The name of the S3 bucket for storing OCR signatures | - | extracted-signatures |
STORAGE_S3_OCR_SIGNATURE_FILENAME | The filename pattern for extracted OCR signatures | - | extracted_signature_{}.png |
STORAGE_S3_ACCESS_KEY | The access key for connecting to the S3 storage service | - | |
STORAGE_S3_SECRET_KEY | The secret key for connecting to the S3 storage service | - |
Please note that the default values and examples provided here are for illustrative purposes. Make sure to replace them with the appropriate values based on your S3 storage configuration.
Performance
| Environment Variable | Definition | Default Value |
|---|---|---|
ENABLE_PERFORMANCE_PAYLOAD | When set to true, the response payload will contain performance metrics related to various stages of the process. | true |
Example
"perf": {
"total_time": 998,
"split": {
"get_file": 248,
"extract_images": 172,
"extract_barcodes": 37,
"extract_signatures": 238,
"minio_signature_save": 301
}
}
Certificates
You can override the following environment variables:
| Environment Variable | Definition | Default Value |
|---|---|---|
REQUESTS_CA_BUNDLE | The path to the certificate bundle file used for secure requests | 5 |
CERT_REQUESTS | If no activity has occurred for a certain number of seconds, an attempt will be made to refresh the workers | 'CERT_REQUIRED' |
Workers Behavior
You can override the following environment variables:
| Environment Variable | Definition | Default Value |
|---|---|---|
OCR_WORKER_COUNT | Number of workers | 5 |
OCR_WORK_QUEUE_TIMEOUT | If no activity has occurred for a certain number of seconds, an attempt will be made to refresh the workers | 10 |
If no worker is released after OCR_WORK_QUEUE_TIMEOUT seconds, the application will verify whether any workers have become unresponsive and need to be restarted.
If none of the workers have died, it means they are likely blocked in some process. In this case, the application will terminate all the workers and shut down itself, hoping that the container will be restarted.
Control Aspect Ratio
| Environment Variable | Definition | Default Value |
|---|---|---|
OCR_SIGNATURE_MAX_RATIO | This variable sets the maximum acceptable aspect ratio for a signed scanned document (the OCR plugin will recognize a signature only if the document ratio is greater than or equal to the specified minimum ratio) | 1.43 |
OCR_SIGNATURE_MIN_RATIO | This variable sets the minimum acceptable aspect ratio for a signed scanned document (in this context, the OCR plugin will consider a detected signature only if the document aspect ratio is less than or equal to the specified maximum ratio) | 1.39 |
The plugin has been tested with aspect ratio values between 1.38 and 1.43. However, caution is advised when using untested values outside this range, as they may potentially disrupt the functionality. Adjust these parameters at your own risk and consider potential consequences, as untested values might lead to plugin instability or undesired behavior.
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