Oracle Multimedia can be extended to support:
Other external sources of media data not currently supported
Other media data formats not currently supported
A new object type
Media (audio and video) data processing
For each unique external media data source or each unique ORDAudio, ORDDoc, or ORDVideo data format you want to support, you must:
Design your new data source or new ORDAudio, ORDDoc, or ORDVideo data format.
Implement your new data source or new ORDAudio, ORDDoc, or ORDVideo data format.
Install your new plug-in into the ORDPLUGINS schema.
Grant EXECUTE privileges on your new plug-in to PUBLIC.
This chapter includes these sections:
To implement your new data source, you must implement the required interfaces in the ORDX_<srcType>_SOURCE package in the ORDPLUGINS schema (where <srcType> represents the name of the new external source type). Use the package body example in Section 7.1.1.3 as a template to create the package body. Then, set the source type parameter in the setSourceInformation( ) call to the appropriate source value to indicate to the ORDAudio, ORDImage, ORDDoc, or ORDVideo object that package ORDPLUGINS.ORDX_<srcType>_SOURCE is available as a plug-in. Use the ORDPLUGINS.ORDX_FILE_SOURCE and ORDPLUGINS.ORDX_HTTP_SOURCE packages as guides when you extend support to other external audio, image, video, or other heterogeneous media data sources.
The following subsection presents reference information on the packages or PL/SQL plug-ins provided:
Plug-ins must be named as ORDX_<name>_<module_name> where the <module_name> is SOURCE for ORDSource. For example, the FILE plug-in described in Section 7.1.1.1 is named ORDX_FILE_SOURCE and the HTTP plug-in described in Section 7.1.1.2 is named ORDX_HTTP_SOURCE and <name> is the source type. Both source type names, FILE and HTTP, are reserved to Oracle.
Use the ORDPLUGINS.ORDX_FILE_SOURCE and ORDPLUGINS.ORDX_HTTP_SOURCE packages as a guide in developing your new source type package.
The following subsections provide examples and more information about extending the supported external sources of audio, image, video, or other heterogeneous media data:
The ORDPLUGINS.ORDX_FILE_SOURCE package or PL/SQL plug-in provides support for multimedia stored in the local file system external to the database.
CREATE OR REPLACE PACKAGE ORDX_FILE_SOURCE AS
-- functions/procedures
FUNCTION processCommand(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
cmd IN VARCHAR2,
arglist IN VARCHAR2,
result OUT RAW)
RETURN RAW;
PROCEDURE import(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
mimetype OUT VARCHAR2,
format OUT VARCHAR2);
PROCEDURE import(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
dlob IN OUT NOCOPY BLOB,
mimetype OUT VARCHAR2,
format OUT VARCHAR2);
PROCEDURE importFrom(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
mimetype OUT VARCHAR2,
format OUT VARCHAR2,
loc IN VARCHAR2,
name IN VARCHAR2);
PROCEDURE importFrom(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
dlob IN OUT NOCOPY BLOB,
mimetype OUT VARCHAR2,
format OUT VARCHAR2,
loc IN VARCHAR2,
name IN VARCHAR2);
PROCEDURE export(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
slob IN OUT NOCOPY BLOB,
loc IN VARCHAR2,
name IN VARCHAR2);
FUNCTION getContentLength(obj IN ORDSYS.ORDSource,
ctx IN OUT RAW),
RETURN INTEGER;
PRAGMA RESTRICT_REFERENCES(getContentLength, WNDS, WNPS, RNDS, RNPS);
FUNCTION getSourceAddress(obj IN ORDSYS.ORDSource,
ctx IN OUT RAW,
userData IN VARCHAR2)
RETURN VARCHAR2;
PRAGMA RESTRICT_REFERENCES(getSourceAddress, WNDS, WNPS, RNDS, RNPS);
FUNCTION open(obj IN OUT NOCOPY ORDSYS.ORDSource,
userArg IN RAW,
ctx OUT RAW) RETURN INTEGER;
FUNCTION close(obj IN OUT NOCOPY ORDSYS.ORDSource, ctx IN OUT RAW)
RETURN INTEGER;
FUNCTION trim(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
newlen IN INTEGER) RETURN INTEGER;
PROCEDURE read(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
startPos IN INTEGER,
numBytes IN OUT INTEGER,
buffer OUT RAW);
PROCEDURE write(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
startPos IN INTEGER,
numBytes IN OUT INTEGER,
buffer OUT RAW);
END ORDX_FILE_SOURCE;
/
Table 7-1 shows the methods supported in the ORDX_FILE_SOURCE package and the exceptions raised if you call a method that is not supported.
Table 7-1 Methods Supported in the ORDPLUGINS.ORDX_FILE_SOURCE Package
| Name of Method | Level of Support |
|---|---|
|
processCommand |
Not supported - raises exception: METHOD_NOT_SUPPORTED |
|
import |
Supported |
|
import |
Supported |
|
importFrom |
Supported |
|
importFrom |
Supported |
|
export |
Supported |
|
getContentLength |
Supported |
|
getSourceAddress |
Supported |
|
open |
Supported |
|
close |
Supported |
|
trim |
Not supported - raises exception: METHOD_NOT_SUPPORTED |
|
read |
Supported |
|
write |
Not supported - raises exception: METHOD_NOT_SUPPORTED |
The ORDPLUGINS.ORDX_HTTP_SOURCE package or PL/SQL plug-in provides support for multimedia stored in any HTTP server and accessed through a URL.
CREATE OR REPLACE PACKAGE ORDX_HTTP_SOURCE AS
-- functions/procedures
FUNCTION processCommand(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
cmd IN VARCHAR2,
arglist IN VARCHAR2,
result OUT RAW)
RETURN RAW;
PROCEDURE import(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
mimetype OUT VARCHAR2,
format OUT VARCHAR2);
PROCEDURE import(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
dlob IN OUT NOCOPY BLOB,
mimetype OUT VARCHAR2,
format OUT VARCHAR2);
PROCEDURE importFrom(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
mimetype OUT VARCHAR2,
format OUT VARCHAR2,
loc IN VARCHAR2,
name IN VARCHAR2);
PROCEDURE importFrom(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
dlob IN OUT NOCOPY BLOB,
mimetype OUT VARCHAR2,
format OUT VARCHAR2,
loc IN VARCHAR2,
name IN VARCHAR2);
PROCEDURE export(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
dlob IN OUT NOCOPY BLOB,
loc IN VARCHAR2,
name IN VARCHAR2);
FUNCTION getContentLength(obj IN ORDSYS.ORDSource,
ctx IN OUT RAW)
RETURN INTEGER;
PRAGMA RESTRICT_REFERENCES(getContentLength, WNDS, WNPS, RNDS, RNPS, TRUST);
FUNCTION getSourceAddress(obj IN ORDSYS.ORDSource,
ctx IN OUT RAW,
userData IN VARCHAR2)
RETURN VARCHAR2;
PRAGMA RESTRICT_REFERENCES(getSourceAddress, WNDS, WNPS, RNDS, RNPS);
FUNCTION open(obj IN OUT NOCOPY ORDSYS.ORDSource, userArg IN RAW,
ctx OUT RAW) RETURN INTEGER;
FUNCTION close(obj IN OUT NOCOPY ORDSYS.ORDSource, ctx IN OUT RAW)
RETURN INTEGER;
FUNCTION trim(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
newlen IN INTEGER) RETURN INTEGER;
PROCEDURE read(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
startPos IN INTEGER,
numBytes IN OUT INTEGER,
buffer OUT RAW);
PROCEDURE write(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
startPos IN INTEGER,
numBytes IN OUT INTEGER,
buffer OUT RAW);
END ORDX_HTTP_SOURCE;
/
Table 7-2 shows the methods supported in the ORDX_HTTP_SOURCE package and the exceptions raised if you call a method that is not supported.
Table 7-2 Methods Supported in the ORDPLUGINS.ORDX_HTTP_SOURCE Package
| Name of Method | Level of Support |
|---|---|
|
processCommand |
Not supported - raises exception: METHOD_NOT_SUPPORTED |
|
import |
Supported |
|
import |
Supported |
|
importFrom |
Supported |
|
importFrom |
Supported |
|
export |
Not supported - raises exception: METHOD_NOT_SUPPORTED |
|
getContentLength |
Supported |
|
getSourceAddress |
Supported |
|
open |
Supported |
|
close |
Supported |
|
trim |
Not supported - raises exception: METHOD_NOT_SUPPORTED |
|
read |
Not supported - raises exception: METHOD_NOT_SUPPORTED |
|
write |
Not supported - raises exception: METHOD_NOT_SUPPORTED |
Extending Oracle Multimedia to support a new data source consists of these steps:
Design your new data source.
Implement your new data source and name it, for example, ORDX_MY_SOURCE.SQL.
Install your new ORDX_MY_SOURCE.SQL plug-in into the ORDPLUGINS schema.
Grant EXECUTE privileges on your new plug-in, for example, ORDX_MY_SOURCE.SQL plug-in to PUBLIC.
Set the srctype to my to cause your plug-in to be invoked.
A package body listing is provided in Example 7-1 to assist you in this operation. Add your variables to the places that say "--Your variables go here" and add your code to the places that say "--Your code goes here".
Example 7-1 Package Body for Extending Support to a New Data Source
CREATE OR REPLACE PACKAGE BODY ORDX_MY_SOURCE
AS
-- functions/procedures
FUNCTION processCommand(
obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
cmd IN VARCHAR2,
arglist IN VARCHAR2,
result OUT RAW)
RETURN RAW
IS
--Your variables go here.
BEGIN
--Your code goes here.
END processCommand;
PROCEDURE import( obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
mimetype OUT VARCHAR2,
format OUT VARCHAR2)
IS
--Your variables go here.
BEGIN
--Your code goes here.
END import;
PROCEDURE import( obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
dlob IN OUT NOCOPY BLOB,
mimetype OUT VARCHAR2,
format OUT VARCHAR2)
IS
--Your variables go here.
BEGIN
--Your code goes here.
END import;
PROCEDURE importFrom( obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
mimetype OUT VARCHAR2,
format OUT VARCHAR2,
loc IN VARCHAR2,
name IN VARCHAR2)
IS
--Your variables go here.
BEGIN
--Your code goes here.
END importFrom;
PROCEDURE importFrom( obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
dlob IN OUT NOCOPY BLOB,
mimetype OUT VARCHAR2,
format OUT VARCHAR2,
loc IN VARCHAR2,
name IN VARCHAR2)
IS
--Your variables go here.
BEGIN
--Your code goes here.
END importFrom;
PROCEDURE export( obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
slob IN OUT NOCOPY BLOB,
loc IN VARCHAR2,
name IN VARCHAR2)
IS
--Your variables go here.
BEGIN
--Your code goes here.
END export;
FUNCTION getContentLength( obj IN ORDSYS.ORDSource,
ctx IN OUT RAW)
RETURN INTEGER
IS
--Your variables go here.
BEGIN
--Your code goes here.
END getContentLength;
FUNCTION getSourceAddress(obj IN ORDSYS.ORDSource,
ctx IN OUT RAW,
userData IN VARCHAR2)
RETURN VARCHAR2
IS
--Your variables go here.
BEGIN
--Your code goes here.
END getSourceAddress;
FUNCTION open(obj IN OUT NOCOPY ORDSYS.ORDSource, userArg IN RAW, ctx OUT RAW)
RETURN INTEGER
IS
--Your variables go here.
BEGIN
--Your code goes here.
END open;
FUNCTION close(obj IN OUT NOCOPY ORDSYS.ORDSource, ctx IN OUT RAW)
RETURN INTEGER
IS
--Your variables go here.
BEGIN
--Your code goes here.
END close;
FUNCTION trim(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
newlen IN INTEGER)
RETURN INTEGER
IS
--Your variables go here.
BEGIN
--Your code goes here.
END trim;
PROCEDURE read(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
startPos IN INTEGER,
numBytes IN OUT INTEGER,
buffer OUT RAW)
IS
--Your variables go here.
BEGIN
--Your code goes here.
END read;
PROCEDURE write(obj IN OUT NOCOPY ORDSYS.ORDSource,
ctx IN OUT RAW,
startPos IN INTEGER,
numBytes IN OUT INTEGER,
buffer OUT RAW)
IS
--Your variables go here.
BEGIN
--Your code goes here.
END write;
END ORDX_MY_SOURCE;
/
show errors;
To implement your new ORDAudio, ORDDoc, or ORDVideo data format, you must implement the required interfaces in the ORDPLUGINS.ORDX_<format>_<media> package in the ORDPLUGINS schema (where <format> represents the name of the new audio or video, or other heterogeneous media data format and <media> represents the type of media ("AUDIO" or "VIDEO", or "DOC"). Use the ORDPLUGINS.ORDX_DEFAULT_<media> package as a guide when you extend support to other audio or video data formats or other heterogeneous media data formats. Use the package body examples in Section 7.2.1.2, Section 7.2.2.2, and Section 7.2.3.2 as templates to create the audio or video, or other heterogeneous media data package body, respectively. Then, set the new format parameter in the
setFormat( ) call to the appropriate format value to indicate to the ORDAudio, ORDDoc, or ORDVideo object that package ORDPLUGINS.ORDX_<format>_<media> is available as a plug-in, and that it must be used for method invocation.
The following subsections describe how to extend Oracle Multimedia to support other data formats:
The following subsections describe how to extend ORDAudio to support other data formats:
Use the following ORDPLUGINS.ORDX_DEFAULT_AUDIO package provided as a guide in developing your own ORDPLUGINS.ORDX_<format>_AUDIO audio format package. This package sets the mimeType field in the setProperties( ) method with a MIME type value that is dependent on the file format.
CREATE OR REPLACE PACKAGE ORDX_DEFAULT_AUDIO
authid current_user
AS
--AUDIO ATTRIBUTES ACCESSORS
PROCEDURE setProperties(ctx IN OUT RAW,
obj IN OUT NOCOPY ORDSYS.ORDAudio,
setComments IN NUMBER := 0);
FUNCTION checkProperties(ctx IN OUT RAW, obj IN OUT ORDSYS.ORDAudio)
RETURN NUMBER;
FUNCTION getAttribute(ctx IN OUT RAW,
obj IN ORDSYS.ORDAudio,
name IN VARCHAR2) RETURN VARCHAR2;
PROCEDURE getAllAttributes(ctx IN OUT RAW,
obj IN ORDSYS.ORDAudio,
attributes IN OUT NOCOPY CLOB);
--AUDIO PROCESSING METHODS
FUNCTION processCommand(ctx IN OUT RAW,
obj IN OUT NOCOPY ORDSYS.ORDAudio,
cmd IN VARCHAR2,
arguments IN VARHAR2,
result OUT RAW)
RETURN RAW;
END;
/
Table 7-3 shows the methods supported in the ORDPLUGINS.ORDX_DEFAULT_AUDIO package and the exceptions raised if you call a method that is not supported.
Table 7-3 Methods Supported in the ORDPLUGINS.ORDX_DEFAULT_AUDIO Package
| Name of Method | Level of Support |
|---|---|
|
setProperties |
Supported; if the source is local, extract attributes from the local data and set the properties, but if the source is |
|
checkProperties |
Supported; if the source is local, extract the attributes from the local data and compare them with the attribute values of the object, but if the source is |
|
getAttribute |
Not supported - raises exceptions: METHOD_NOT_SUPPORTED and AUDIO_PLUGIN_EXCEPTION. |
|
getAllAttributes |
Supported; if the source is local, get the attributes and return them, but if the source is |
|
processCommand |
Not supported - raises exceptions: METHOD_NOT_SUPPORTED and AUDIO_PLUGIN_EXCEPTION. |
Extending Oracle Multimedia to support a new audio data format consists of the following steps:
Design your new audio data format.
To support a new audio data format, implement the required interfaces in the ORDX_<format>_AUDIO package in the ORDPLUGINS schema (where <format> represents the name of the new audio data format). See Section 7.2.1.1 for a complete description of the interfaces for the ORDX_DEFAULT_AUDIO package. Use the package body example in Example 7-2 as a template to create the audio package body.
Then, set the new format parameter in the setFormat( ) call to the appropriate format value to indicate to the audio object that package ORDPLUGINS.ORDX_<format>_AUDIO is available as a plug-in.
Implement your new audio data format and name it, for example, ORDX_MY_AUDIO.SQL.
Install your new ORDX_MY_AUDIO.SQL plug-in into the ORDPLUGINS schema.
Grant EXECUTE privileges on your new plug-in, for example, ORDX_MY_AUDIO plug-in, to PUBLIC.
In an application, set the format attribute to my to cause your plug-in to be invoked.
A package body listing is provided in Example 7-2 to assist you in this operation. Add your variables to the places that say "--Your variables go here" and add your code to the places that say "--Your code goes here".
Example 7-2 Package Body for Extending Support to a New Audio Data Format
CREATE OR REPLACE PACKAGE BODY ORDX_MY_AUDIO
AS
--AUDIO ATTRIBUTES ACCESSORS
PROCEDURE setProperties(ctx IN OUT RAW,
obj IN OUT NOCOPY ORDSYS.ORDAudio,
setComments IN NUMBER :=0)
IS
--Your variables go here.
BEGIN
--Your code goes here.
END;
FUNCTION checkProperties(ctx IN OUT RAW, obj IN OUT ORDSYS.ORDAudio)
RETURN NUMBER
IS
--Your variables go here.
BEGIN
--Your code goes here.
END;
FUNCTION getAttribute(ctx IN OUT RAW,
obj IN ORDSYS.ORDAudio,
name IN VARCHAR2)
RETURN VARCHAR2
IS
--Your variables go here.
BEGIN
--Your code goes here.
END;
PROCEDURE getAllAttributes(ctx IN OUT RAW,
obj IN ORDSYS.ORDAudio,
attributes IN OUT NOCOPY CLOB)
IS
--Your variables go here.
BEGIN
--Your code goes here.
END;
-- AUDIO PROCESSING METHODS
FUNCTION processCommand(
ctx IN OUT RAW,
obj IN OUT NOCOPY ORDSYS.ORDAudio,
cmd IN VARCHAR2,
arguments IN VARCHAR2,
result OUT RAW)
RETURN RAW
IS
--Your variables go here.
BEGIN
--Your code goes here.
END;
END;
/
show errors;
The following subsections describe how to extend ORDDoc to support other data formats:
Use the following ORDPLUGINS.ORDX_DEFAULT_DOC package provided as a guide in developing your own ORDPLUGINS.ORDX_<format>_DOC media format package.
CREATE OR REPLACE PACKAGE ORDX_DEFAULT_DOC
authid current_user
AS
PROCEDURE setProperties(ctx IN OUT RAW,
obj IN OUT NOCOPY ORDSYS.ORDDoc,
setComments IN NUMBER := 0);
END;
/
Table 7-4 shows the method supported in the ORDPLUGINS.ORDX_DEFAULT_DOC package and the exception raised if the source is NULL.
Table 7-4 Method Supported in the ORDPLUGINS.ORDX_DEFAULT_DOC Package
| Name of Method | Level of Support |
|---|---|
|
setProperties |
Supported; if the source is local, extract attributes from the local data and set the properties, but if the source is |
Extending Oracle Multimedia to support a new ORDDoc data format consists of the following steps:
Design your new media data format.
To support a new media data format, implement the required interfaces in the ORDX_<format>_DOC package in the ORDPLUGINS schema (where <format> represents the name of the new media data format). See Section 7.2.2.1 for a complete description of the interfaces for the ORDX_DEFAULT_DOC package. Use the package body example in Example 7-3 as a template to create the package body.
Then, set the new format parameter in the setFormat( ) call to the appropriate format value to indicate to the media object that package ORDPLUGINS.ORDX_<format>_DOC is available as a plug-in.
Implement your new media data format and name it, for example, ORDX_MY_DOC.SQL.
Install your new ORDX_MY_DOC.SQL plug-in into the ORDPLUGINS schema.
Grant EXECUTE privileges on your new plug-in, for example, ORDX_MY_DOC plug-in, to PUBLIC.
In an application, set the format to my to cause your plug-in to be invoked.
A package body listing is provided in Example 7-3 to assist you in this operation. Add your variables to the places that say "--Your variables go here" and add your code to the places that say "--Your code goes here".
Example 7-3 Package Body for Extending Support to a New ORDDoc Data Format
CREATE OR REPLACE PACKAGE BODY ORDX_MY_DOC
AS
--DOCUMENT ATTRIBUTES ACCESSORS
PROCEDURE setProperties(ctx IN OUT RAW,
obj IN OUT NOCOPY ORDSYS.ORDDoc,
setComments IN NUMBER :=0)
IS
--Your variables go here.
BEGIN
--Your code goes here.
END;
END;
/
show errors;
The following subsections describe how to extend ORDVideo to support other data formats:
Use the following ORDPLUGINS.ORDX_DEFAULT_VIDEO package provided as a guide in developing your own ORDPLUGINS.ORDX_<format>_VIDEO video format package. This package sets the mimeType field in the setProperties( ) method with a MIME type value that is dependent on the file format.
CREATE OR REPLACE PACKAGE ORDX_DEFAULT_VIDEO
authid current_user
AS
--VIDEO ATTRIBUTES ACCESSORS
FUNCTION getAttribute(ctx IN OUT RAW,
obj IN ORDSYS.ORDVideo,
name IN VARCHAR2)
RETURN VARCHAR2;
PROCEDURE setProperties(ctx IN OUT RAW,
obj IN OUT NOCOPY ORDSYS.ORDVideo,
setComments IN NUMBER := 0);
FUNCTION checkProperties(ctx IN OUT RAW,obj IN ORDSYS.ORDVideo) RETURN NUMBER;
-- must return name=value; name=value; ... pairs
PROCEDURE getAllAttributes(ctx IN OUT RAW,
obj IN ORDSYS.ORDVideo,
attributes IN OUT NOCOPY CLOB);
-- VIDEO PROCESSING METHODS
FUNCTION processCommand(
ctx IN OUT RAW,
obj IN OUT NOCOPY ORDSYS.ORDVideo,
cmd IN VARCHAR2,
arguments IN VARCHAR2,
result OUT RAW)
RETURN RAW;
END;
/
Table 7-5 shows the methods supported in the ORDPLUGINS.ORDX_DEFAULT_VIDEO package and the exceptions raised if you call a method that is not supported.
Table 7-5 Methods Supported in the ORDPLUGINS.ORDX_DEFAULT_VIDEO Package
| Name of Method | Level of Support |
|---|---|
|
getAttribute |
Not supported - raises exceptions: METHOD_NOT_SUPPORTED and VIDEO_PLUGIN_EXCEPTION |
|
setProperties |
Supported; if the source is local, extract attributes from the local data and set the properties, but if the source is |
|
checkProperties |
Supported; if the source is local, extract attributes from the local data and compare them with the attribute values of the object, but if the source is |
|
getAllAttributes |
Supported; if the source is local, get the attributes and return them, but if the source is |
|
processCommand |
Not supported - raises exceptions: METHOD_NOT_SUPPORTED and VIDEO_PLUGIN_EXCEPTION |
Extending Oracle Multimedia to support a new video data format consists of the following steps:
Design your new video data format.
To support a new video data format, implement the required interfaces in the ORDX_<format>_VIDEO package in the ORDPLUGINS schema (where <format> represents the name of the new video data format). See Section 7.2.3.1 for a complete description of the interfaces for the ORDX_DEFAULT_VIDEO package. Use the package body example in Example 7-4 as a template to create the video package body.
Then, set the new format parameter in the setFormat( ) call to the appropriate format value to indicate to the video object that package ORDPLUGINS.ORDX_<format>_VIDEO is available as a plug-in.
Implement your new video data format and name it, for example, ORDX_MY_VIDEO.SQL.
Install your new ORDX_MY_VIDEO.SQL plug-in into the ORDPLUGINS schema.
Grant EXECUTE privileges on your new plug-in, for example, ORDX_MY_VIDEO plug-in, to PUBLIC.
In an application, set the video format to my to cause your plug-in to be invoked.
A package body listing is provided in Example 7-4 to assist you in this operation. Add your variables to the places that say "--Your variables go here" and add your code to the places that say "--Your code goes here".
Example 7-4 Package Body for Extending Support to a New Video Data Format
CREATE OR REPLACE PACKAGE BODY ORDX_MY_VIDEO
AS
--VIDEO ATTRIBUTES ACCESSORS
FUNCTION getAttribute(ctx IN OUT RAW,
obj IN ORDSYS.ORDVideo,
name IN VARCHAR2)
RETURN VARCHAR2
IS
--Your variables go here.
BEGIN
--Your code goes here.
END;
PROCEDURE setProperties(ctx IN OUT RAW,
obj IN OUT NOCOPY ORDSYS.ORDVideo,
setComments IN NUMBER :=0)
IS
--Your variables go here.
BEGIN
--Your code goes here.
END;
FUNCTION checkProperties(ctx IN OUT RAW, obj IN ORDSYS.ORDVideo) RETURN NUMBER
IS
--Your variables go here.
BEGIN
--Your code goes here.
END;
PROCEDURE getAllAttributes(ctx IN OUT RAW,
obj IN ORDSYS.ORDVideo,
attributes IN OUT NOCOPY CLOB)
IS
--Your variables go here.
BEGIN
--Your code goes here.
END;
-- VIDEO PROCESSING METHODS
FUNCTION processCommand(
ctx IN OUT RAW,
obj IN OUT NOCOPY ORDSYS.ORDVideo,
cmd IN VARCHAR2,
arguments IN VARCHAR2,
result OUT RAW)
RETURN RAW
IS
--Your variables go here.
BEGIN
--Your code goes here.
END;
END;
/
show errors;
Oracle Multimedia supports certain other image formats through the setProperties( ) method for foreign images. This method enables other image formats to be recognized by writing the values supplied to the setProperties( ) method for foreign images to the existing ORDImage data attributes.
See Also:
The setProperties( ) for foreign images method in Oracle Multimedia Reference for more information, and to determine the type of images that are supported this way
You can use any of the Oracle Multimedia objects types as the basis for a new type of your own creation, as shown in Example 7-5 for the ORDImage object type.
Note:
When a type is altered, any dependent type definitions are invalidated. You will encounter this problem if you define a new type that includes an Oracle Multimedia object type attribute and the Oracle Multimedia object type is altered, which always occurs during an Oracle Multimedia installation upgrade.A workaround to this problem is to revalidate all invalid type definitions with the following SQL statement:
SQL> ALTER TYPE <type-name> COMPILE;
Example 7-5 Extend Oracle Multimedia ORDImage with a New Object Type
CREATE TYPE AnnotatedImage AS OBJECT
( image ORDSYS.ORDImage,
description VARCHAR2(2000),
MEMBER PROCEDURE SetProperties(SELF IN OUT AnnotatedImage),
MEMBER PROCEDURE Copy(dest IN OUT AnnotatedImage),
MEMBER PROCEDURE ProcessCopy(command IN VARCHAR2,
dest IN OUT AnnotatedImage)
);
/
CREATE TYPE BODY AnnotatedImage AS
MEMBER PROCEDURE SetProperties(SELF IN OUT AnnotatedImage) IS
BEGIN
SELF.image.setProperties();
SELF.description :=
'This is an example of using Image object as a subtype';
END SetProperties;
MEMBER PROCEDURE Copy(dest IN OUT AnnotatedImage) IS
BEGIN
SELF.image.copy(dest.image);
dest.description := SELF.description;
END Copy;
MEMBER PROCEDURE ProcessCopy(command IN VARCHAR2,
dest IN OUT AnnotatedImage) IS
BEGIN
SELF.Image.processCopy(command,dest.image);
dest.description := SELF.description;
END ProcessCopy;
END;
/
After creating the new type, you can use it as you would any other type. For example:
CREATE OR REPLACE DIRECTORY ORDIMGDIR AS 'C:\TESTS';
CREATE TABLE my_example(id NUMBER, an_image AnnotatedImage);
INSERT INTO my_example VALUES (1,
AnnotatedImage(
ORDSYS.ORDImage.init('file','ORDIMGDIR','plaid.gif'));
COMMIT;
DECLARE
myimage AnnotatedImage;
BEGIN
SELECT an_image INTO myimage FROM my_example;
myimage.SetProperties;
DBMS_OUTPUT.PUT_LINE('This image has a description of ');
DBMS_OUTPUT.PUT_LINE(myimage.description);
UPDATE my_example SET an_image = myimage;
END;
/
Oracle Multimedia also supports the processing of audio and video data, as described in the following subsections:
To support audio data processing, that is, the passing of an audio processing command and set of arguments to a format plug-in for processing, use the
processAudioCommand( ) method. This method is available only for user-defined formats.
See Also:
The processAudioCommand( ) method in Oracle Multimedia Reference for a description
To support video data processing, that is, the passing of a command and set of arguments to a format plug-in for processing, use the processVideoCommand( ) method. This method is only available for user-defined formats.
See Also:
The processVideoCommand( ) method in Oracle Multimedia Reference for a description