Package org.opencastproject.workflow.handler.textanalyzer

Class TextAnalysisWorkflowOperationHandler

java.lang.Object

org.opencastproject.workflow.api.AbstractWorkflowOperationHandler

org.opencastproject.workflow.handler.textanalyzer.TextAnalysisWorkflowOperationHandler

All Implemented Interfaces:

WorkflowOperationHandler

public class TextAnalysisWorkflowOperationHandler
extends AbstractWorkflowOperationHandler

The TextAnalysisOperationHandler will take an MPEG-7 catalog, look for video segments and run a text analysis on the associated still images. The resulting VideoText elements will then be added to the segments.

Nested Class Summary

Nested classes/interfaces inherited from class org.opencastproject.workflow.api.AbstractWorkflowOperationHandler

AbstractWorkflowOperationHandler.Configuration

Field Summary

Fields

Modifier and Type	Field	Description
protected ComposerService	composer	The composer service
static final String	IMAGE_EXTRACTION_PROFILE	Name of the encoding profile that extracts a still image from a movie
static final String	OPT_STABILITY_THRESHOLD	Name of the constant used to retreive the stability threshold

Fields inherited from class org.opencastproject.workflow.api.AbstractWorkflowOperationHandler

description, id, serviceRegistry, SOURCE_FLAVOR, SOURCE_FLAVORS, SOURCE_TAG, SOURCE_TAGS, TARGET_FLAVOR, TARGET_FLAVORS, TARGET_TAG, TARGET_TAGS, workspace

Constructor Summary

Constructors

Constructor	Description
TextAnalysisWorkflowOperationHandler()

Method Summary

Modifier and Type	Method	Description
void	activate(org.osgi.service.component.ComponentContext cc)	Activates this component with its properties once all of the collaborating services have been set
protected WorkflowOperationResult	extractVideoText(MediaPackage mediaPackage, WorkflowOperationInstance operation, ConfiguredTagsAndFlavors tagsAndFlavors)	Runs the text analysis service on each of the video segments found.
protected Mpeg7Catalog	loadMpeg7Catalog(Catalog catalog)	Loads an mpeg7 catalog from a mediapackage's catalog reference
protected Map<Catalog,Mpeg7Catalog>	loadSegmentCatalogs(MediaPackage mediaPackage, WorkflowOperationInstance operation, ConfiguredTagsAndFlavors tagsAndFlavors)	Extracts the catalogs from the media package that match the requirements of flavor and tags specified in the operation handler.
void	modified(org.osgi.service.component.ComponentContext cc)
protected void	setMpeg7CatalogService(Mpeg7CatalogService catalogService)	Callback for the OSGi declarative services configuration.
void	setServiceRegistry(ServiceRegistry serviceRegistry)	Sets the service registry.
protected void	setTextAnalyzer(TextAnalyzerService analysisService)	Callback for the OSGi declarative services configuration that will set the text analysis service.
void	setWorkspace(Workspace workspace)	Callback for declarative services configuration that will introduce us to the local workspace service.
WorkflowOperationResult	start(WorkflowInstance workflowInstance, JobContext context)	Runs the workflow operation on this WorkflowInstance.
void	updated(Dictionary properties)

Methods inherited from class org.opencastproject.workflow.api.AbstractWorkflowOperationHandler

applyTargetTagsToElement, asList, createDerivedMediaPackageElementFrom, createResult, createResult, createResult, createResult, describeFailedJobs, destroy, equals, getConfig, getConfig, getConfig, getDescription, getFileNameFromElements, getId, getOptConfig, getOptConfig, getTagsAndFlavors, getTagsAndFlavors, hashCode, setJobBarrierPollingInterval, skip, toString, waitForStatus, waitForStatus

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Details

IMAGE_EXTRACTION_PROFILE

public static final String IMAGE_EXTRACTION_PROFILE

Name of the encoding profile that extracts a still image from a movie

See Also:

• Constant Field Values

OPT_STABILITY_THRESHOLD

public static final String OPT_STABILITY_THRESHOLD

Name of the constant used to retreive the stability threshold

See Also:

• Constant Field Values

composer

protected ComposerService composer

The composer service

Constructor Details

TextAnalysisWorkflowOperationHandler

public TextAnalysisWorkflowOperationHandler()

Method Details

setTextAnalyzer

protected void setTextAnalyzer(TextAnalyzerService analysisService)

Callback for the OSGi declarative services configuration that will set the text analysis service.

Parameters:

analysisService - the text analysis service

setWorkspace

public void setWorkspace(Workspace workspace)

Callback for declarative services configuration that will introduce us to the local workspace service. Implementation assumes that the reference is configured as being static.

Parameters:

workspace - an instance of the workspace

setMpeg7CatalogService

protected void setMpeg7CatalogService(Mpeg7CatalogService catalogService)

Callback for the OSGi declarative services configuration.

Parameters:

catalogService - the catalog service

start

public WorkflowOperationResult start(WorkflowInstance workflowInstance,
 JobContext context)
                              throws WorkflowOperationException

Description copied from class: AbstractWorkflowOperationHandler

Runs the workflow operation on this WorkflowInstance. If the execution fails for some reason, this must throw a WorkflowOperationException in order to handle the problem gracefully. Runtime exceptions will cause the entire workflow instance to fail.

Specified by:

start in interface WorkflowOperationHandler

Specified by:

start in class AbstractWorkflowOperationHandler

Parameters:

workflowInstance - the workflow instance

context - the job context

Returns:

the WorkflowOperationResult containing a potentially modified MediaPackage and whether to put the workflow instance into a wait state.

Throws:

WorkflowOperationException - If the workflow operation fails to execute properly, and the default error handling should be invoked.

See Also:

• WorkflowOperationHandler.start(org.opencastproject.workflow.api.WorkflowInstance, JobContext)

extractVideoText

protected WorkflowOperationResult extractVideoText(MediaPackage mediaPackage,
 WorkflowOperationInstance operation,
 ConfiguredTagsAndFlavors tagsAndFlavors)
                                            throws EncoderException,
InterruptedException,
ExecutionException,
IOException,
NotFoundException,
MediaPackageException,
TextAnalyzerException,
WorkflowOperationException,
ServiceRegistryException

Runs the text analysis service on each of the video segments found.

Parameters:

mediaPackage - the original mediapackage

operation - the workflow operation

Throws:

ExecutionException

InterruptedException

NotFoundException

WorkflowOperationException

EncoderException

IOException

MediaPackageException

TextAnalyzerException

ServiceRegistryException

loadMpeg7Catalog

protected Mpeg7Catalog loadMpeg7Catalog(Catalog catalog)
                                 throws IOException

Loads an mpeg7 catalog from a mediapackage's catalog reference

Parameters:

catalog - the mediapackage's reference to this catalog

Returns:

the mpeg7

Throws:

IOException - if there is a problem loading or parsing the mpeg7 object

loadSegmentCatalogs

protected Map<Catalog,Mpeg7Catalog> loadSegmentCatalogs(MediaPackage mediaPackage,
 WorkflowOperationInstance operation,
 ConfiguredTagsAndFlavors tagsAndFlavors)
                                                 throws IOException

Extracts the catalogs from the media package that match the requirements of flavor and tags specified in the operation handler.

Parameters:

mediaPackage - the media package

operation - the workflow operation

Returns:

a map of catalog elements and their mpeg-7 representations

Throws:

IOException - if there is a problem reading the mpeg7

activate

public void activate(org.osgi.service.component.ComponentContext cc)

Description copied from class: AbstractWorkflowOperationHandler

Activates this component with its properties once all of the collaborating services have been set

Overrides:

activate in class AbstractWorkflowOperationHandler

Parameters:

cc - The component's context, containing the properties used for configuration

modified

public void modified(org.osgi.service.component.ComponentContext cc)

updated

public void updated(Dictionary properties)

setServiceRegistry

public void setServiceRegistry(ServiceRegistry serviceRegistry)

Description copied from class: AbstractWorkflowOperationHandler

Sets the service registry. This method is here as a convenience for developers that need the registry to do job waiting.

Overrides:

setServiceRegistry in class AbstractWorkflowOperationHandler

Parameters:

serviceRegistry - the service registry