cScriptTypes

Provides the global 'types' object within scripts. More...

Inheritance diagram for cScriptTypes:

Public Member Functions
Q_INVOKABLE QObject *	createDefinition (const QString &strStructName)
	Create a new cScriptStructure definition. More...
Q_INVOKABLE QObject *	getDefinition (const QString &strStructName)
	Returns a stream type with a media description set from the Media Description Service. More...
Q_INVOKABLE QObject *	createStreamType (const QString &strMetaType)
	Create a new cStreamTypeWrapper instance with the given Stream Meta Type. More...
Q_INVOKABLE QObject *	createPlainStreamType (const QString &strCType)
	Create a new cStreamTypeWrapper instance for a adtf/plain stream type with the a given c-type. More...
Q_INVOKABLE QObject *	createSubStreamsType ()
	Creates a stream type that can handle Substreams. More...
Q_INVOKABLE QObject *	fromDescriptionFile (const QString &strStructName, const QString &strFileName, bool bResolveStruct=true)
	Creates an 'adtf/default' Stream Type from the given media description file. More...
Q_INVOKABLE QObject *	fromDescriptionString (const QString &strStructName, const QString &strMediaDescription, bool bResolveStruct=true)
	Creates an 'adtf/default' Stream Type from the given media description string. More...

Private Attributes
QJSEngine &	m_oEngine
adtf::util::cFilepath	m_strScriptFolder

Detailed Description

Provides the global 'types' object within scripts.

Definition at line 138 of file builds/digitalwerk/solutions/adtf_content/adtf_base/adtf_core/src/libraries/javascriptfiltersdk/src/types.h.

Member Function Documentation

createDefinition()

Q_INVOKABLE QObject* createDefinition

(

const QString &

strStructName

)

Create a new cScriptStructure definition.

Example Usage

var outputType = types.createDefinition("my_data")
                 .add("value1", "tUInt32")
                 .add("value2", "tFloat32")
var output = filter.createOutputPin("output", outputType)
 
var runner = filter.createRunner("generate_data")
var counter = 0
runner.trigger.connect(function(timestamp)
{
    output.write(timestamp, {value1: counter, value2: counter})
    ++counter
})

Parameters

[in]

strStructName

The name of the structure.

Returns

a cScriptStructure instance.

createPlainStreamType()

Q_INVOKABLE QObject* createPlainStreamType

(

const QString &

strCType

)

Create a new cStreamTypeWrapper instance for a adtf/plain stream type with the a given c-type.

Example Usage

Parameters

[in]

strCType

The c-type name ( bool, int8, uint8, int16, uint16, " "int32, uint32, int64, uint64, float, double)

Returns

a cStreamTypeWrapper instance.

createStreamType()

Q_INVOKABLE QObject* createStreamType

(

const QString &

strMetaType

)

Create a new cStreamTypeWrapper instance with the given Stream Meta Type.

This allows you to create any stream type manually by setting the Properties.

Example Usage

var type = types.createStreamType("demo/my_special_type")
type.setProperty("my_property", 3.1415)
 
var output = filter.createOutputPin("output", type)
 
var runner = filter.createRunner("generate_data")
var counter = 0
runner.trigger.connect(function(timestamp)
{
    // the stream type does not contain a media description so we can only send raw data
    var data = new Int32Array(1);
    data[0] = counter
 
    output.write(timestamp, data.buffer)
 
    ++counter
})

Parameters

[in]

strMetaType

The Stream Meta Type.

Returns

a cStreamTypeWrapper instance.

createSubStreamsType()

Q_INVOKABLE QObject* createSubStreamsType

(

)

Creates a stream type that can handle Substreams.

Example Usage

var outputType = types.createDefinition("my_data")
                 .add("value", "tUInt32")
 
var sub_streams = types.createSubStreamsType()
sub_streams.setSubStream("stream1", 1, outputType)
sub_streams.setSubStream("stream2", 2, outputType)
 
var output = filter.createOutputPin("output", sub_streams)
 
var runner = filter.createRunner("generate_data")
var counter = 0
runner.trigger.connect(function(timestamp)
{
    output.writeSubStream(timestamp, "stream1", {value: counter})
    output.writeSubStream(timestamp, "stream2", {value: counter * 2})
    ++counter
})

Returns

a cSubStreamsTypeWrapper instance.

fromDescriptionFile()

Q_INVOKABLE QObject* fromDescriptionFile	(	const QString &	strStructName,
		const QString &	strFileName,
		bool	bResolveStruct = true
	)

Creates an 'adtf/default' Stream Type from the given media description file.

Example Usage

var type = types.fromDescriptionFile("my_data", "my_description.description")
var output = filter.createOutputPin("output", type)
 
var runner = filter.createRunner("generate_data")
var counter = 0
runner.trigger.connect(function(timestamp)
{
    output.write(timestamp, {element_from_description: counter})
    ++counter
})

Parameters

[in]	strStructName	The name of the struct within the .description file
[in]	strFileName	The filename of the .description file. You can use macros as well. Relative filenames are resolved with respect to the script file.
[in]	bResolveStruct	If true, the DDL will be reduced to contain only the definition of strStructName and its dependencies.

Returns

a cStreamTypeWrapper instance.

fromDescriptionString()

Q_INVOKABLE QObject* fromDescriptionString	(	const QString &	strStructName,
		const QString &	strMediaDescription,
		bool	bResolveStruct = true
	)

Creates an 'adtf/default' Stream Type from the given media description string.

Example Usage

var type = types.fromDescriptionString("my_data",
                                       "<structs>\
                                               <struct name=\"my_data\" version=\"1\" ddlversion=\"4.0\">\
                                                       <element name=\"element_from_description\" type=\"tUInt32\" arraysize=\"1\">\
                                                               <deserialized alignment=\"1\"/>\
                                                               <serialized bytepos=\"0\" byteorder=\"LE\"/>\
                                                       </element>\
                                               </struct>\
                                       </structs>")
var output = filter.createOutputPin("output", type)
 
var runner = filter.createRunner("generate_data")
var counter = 0
runner.trigger.connect(function(timestamp)
{
    output.write(timestamp, {element_from_description: counter})
    ++counter
})

Parameters

[in]	strStructName	The name of the struct within the .description file
[in]	strMediaDescription	The string containing the media description.
[in]	bResolveStruct	If true, the DDL will be reduced to contain only the definition of strStructName and its dependencies.

Returns

a cStreamTypeWrapper instance.

getDefinition()

Q_INVOKABLE QObject* getDefinition

(

const QString &

strStructName

)

Returns a stream type with a media description set from the Media Description Service.

Please mind that the prefered way to use description files in scripting is via the fromDescriptionFile() method.

Example Usage

// this defintion must be loaded from a description file by the Media Description Service.
var type = types.getDefinition("my_data_from_service")
var output = filter.createOutputPin("output", type)
 
var runner = filter.createRunner("generate_data")
var counter = 0
runner.trigger.connect(function(timestamp)
{
    output.write(timestamp, {element_from_description: counter})
    ++counter
})

Parameters

[in]

strStructName

The name of the structure that should be retrieved from the service..

Returns

a cStreamTypeWrapper instance.