1 Introduction
Content Access is part of Oracle's family of OEM products known as Outside In Technology, a powerful document extraction, conversion and viewing technology that can access the information in more than 600 file formats. Content Access is a server-grade technology that provides developers with normalized access to content stored in documents across multiple platforms.
There may be references to other Outside In Technology SDKs within this manual. To obtain complete documentation for any other Outside In product, see:
http://www.oracle.com/technetwork/indexes/documentation/index.html#middleware
and click on Outside In Technology.
This chapter includes the following sections:
1.1 What's New in this Release
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The updated list of supported formats is linked from the page
http://www.outsideinsdk.com/
. Look for the data sheet with the latest supported formats. -
Support has been added for IBM Lotus Notes NTF (Win32, Win64, Linux x86-32 and Oracle Solaris 32-bit only with Notes Client or Domino Server) 8.x.
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Support has been added for Ichicatro 2014.
1.2 What Does This Technology Do?
Outside In Content Access provides a simple interface to extract text and metadata from business documents. This technology is particularly useful for document indexing applications. The product is comprised of two modules: Content Access and Text Access. Benefits include:
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The ability to extract text from documents with automatic translation into a particular character set, such as Unicode or ANSI.
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Access to numerous additional properties of documents that store information such as author, keywords, typist, version notes, carbon copy, checked by, subject, character and paragraph attributes, and so forth.
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A common interface to the content of diverse file formats including word processing, spreadsheet, database, email, vector, and presentation formats.
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The Text Access module's specific functions have tight integration with Outside In Technology, such that text generated by the text access functions is highlighted in the Viewer.
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Text Access and Content Access generate the same raw text. However, the following points are important.
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rawtext and Text Access will extract some text as unmappable characters because they cannot be annotated. This includes text that is not visible (for example, document properties, hidden text, and so on.).
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rawtext and Text Access only operate on the top-most layer of the file, and will not extract text from embedded documents. Thus, not all visible text will be extractable via rawtext or Text Access.
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Content Access can be used to extract hidden text, like document properties; and text from embedded documents.
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It should be noted that other Outside In products offer powerful text extraction and tagging abilities, such as Search Export and XML Export.
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1.3 Architectural Overview
The basic architecture of Content Access is the same across all supported platforms:
Filter/Module | Description |
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Input Filter | The input filters form the base of the architecture. Each one reads a specific file format or set of related formats and sends the data to the chunker module through a standard set of function calls. There are more than 150 of these filters that read more than 600 distinct file formats. Filters are loaded on demand by the data access module. |
Chunker | The Chunker module is responsible for caching a certain amount of data from the filter and returning this data to the Content Access module. |
Content Access | The Content Access module reads data from the chunker and repackages it in a way that is convenient for the developer. This repackaging process includes mapping characters to a particular character set and converting some data (such as paragraph and cell breaks) into representative characters. CA outputs non-visible text, provides a wealth of style information, provides the information needed for the consumer to process sub-documents, and optionally produces non-textual information such as numbers in spreadsheets. |
Text Access | The Text Access module is similar to the Content Access module, although it is restricted to text. For more information, see Chapter 5, "Text Access Functions." |
Data Access | The Data Access module implements a generic API for access to files. It understands how to identify and load the correct filter for all the supported file formats. The module delivers to the developer a generic handle to the requested file, which can then be used to run more specialized processes. The Data Access module is responsible for providing a document for the Content Access module. Data Access conserves resources by creating only one file handle and one chunker handle for each file, even if it is opened in multiple Content Access instances. It also provides a unified platform for several modules in addition to Content Access, including Text Access and Remote Filter Access. |
1.4 Definition of Terms
The following table provides definitions of some common terms.
Term | Definition |
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Developer | Someone integrating this technology into another technology or application. Most likely this is you, the reader. |
Source File | The file the developer wishes to extract content from. |
Data Access Module | The core of Outside In Data Access, in the SCCDA library. |
Data Access Submodule (also referred to as "Submodule") | This refers to any of the Outside In Data Access modules, including SCCCA (Content Access) and SCCTA (Text Access), but excluding SCCDA (Data Access). |
Document Handle (also referred to as "hDoc ") |
A Document Handle is created when a file is opened using Data Access (see Chapter 4, "Data Access Common Functions"). Each Document Handle may have any number of Subhandles. |
Content Handle (also referred to as "hItem ") |
The handle created by a call to CAOpenContent or TAOpenText. Every Content Handle has a Document Handle associated with it. The DASetOption and DAGetOption functions in the Data Access Module may be called with any Content Handle or Document Handle. The DARetrieveDocHandle function returns the Document Handle associated with any Content Handle. |
1.5 Directory Structure
Each Outside In product has an sdk directory, under which there is a subdirectory for each platform on which the product ships (for example, ca/sdk/ca_win-x86-32_sdk). Under each of these directories are the following three subdirectories:
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redist: Contains only the files that the customer is allowed to redistribute. These include all the compiled modules, filter support files, .xsd and .dtd files, cmmap000.bin, and third-party libraries, like freetype.
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sdk: Contains the other subdirectories that used to be at the root-level of an sdk (common, lib (windows only), resource, samplefiles, and samplecode (previously samples). In addition, one new subdirectory has been added, demo, that holds all of the compiled sample apps and other files that are needed to demo the products. These are files that the customer should not redistribute (.cfg files, exportmaps, and so forth).
In the root platform directory (for example, ca/sdk/ca_win-x86-32_sdk), there are two files:
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README: Explains the contents of the sdk, and that makedemo must be run in order to use the sample applications.
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makedemo (either .bat or .sh – platform-based): This script will either copy (on Windows) or Symlink (on UNIX) the contents of …/redist into …/sdk/demo, so that sample applications can then be run out of the demo directory.
1.6 How to Use Content Access
Here's a step-by-step overview of how to obtain information from a source file using Content Access.
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Call DAInitEx to initialize the Data Access technology. This function needs to be called only once per application. If using threading, then pass in the correct ThreadOption.
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Set "Null" options: Certain options need to be set before the desired source file is opened. These options are identified by requiring a NULL handle type. They include, but aren't limited to:
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SCCOPT_FALLBACKFORMAT
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SCCOPT_FIFLAGS
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SCCOPT_TEMPDIR
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Open the Source File: DAOpenDocument is called to create a document handle that uniquely identifies the source file. This handle may be used in subsequent calls to the CAOpenContent function or the open function of any other Data Access Submodule, and will be used to close the file when access is complete. This allows the file to be accessed from multiple Data Access Submodules without reopening.
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Set other Options: Once the source document has been opened, set any other desired options. Most options will be set at this time and are identified by requiring a VTHDOC handle type.
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Open a Handle to Content Access: Using the document handle, CAOpenContent is called to obtain a content handle that identifies the file to the Content Access module. This handle will used in all subsequent calls to the Content Access functions.
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Retrieve the first Information from the File: Call CAReadFirst to read the first piece of information from the file. Note: this step may be repeated to reread the file.
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Retrieve other Information from the File: Repeatedly call CAReadNext, which will iteratively read through and process the file.
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Process sub-documents (Optional): When you encounter a sub-document, you may process that sub-document by repeating steps 4-10. Sub-documents are identified by either the SCCCA_OBJECT type or the SCCCA_LINKEDOBJECT subtype of the SCCCA_BEGINTAG type. Note: the document handle and content handle will be different for the parent and sub-document.
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Close the Content Access Handle: Call CACloseContent to terminate the content access for the file. After this function is called, the content handle will no longer be valid, but the document handle may still be used.
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Close the Source File: DACloseDocument is called to close the source file. After calling this function, the document handle will no longer be valid.
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De-initialize DA: DADeInit is called to de-initialize the Data Access technology.
1.7 How to Use Text Access
Here's a step-by-step overview of how to obtain information from a source file using Text Access.
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Call DAInitEx to initialize the Data Access technology. This function needs to be called only once per application. If using threading, then pass in the correct ThreadOption.
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Set "Null" options: Certain options need to be set before the desired source file is opened. These options are identified by requiring a NULL handle type. They include, but aren't limited to:
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SCCOPT_FALLBACKFORMAT
-
SCCOPT_FIFLAGS
-
SCCOPT_TEMPDIR
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Open the Source File: DAOpenDocument is called to create a document handle that uniquely identifies the source file. This handle may be used in subsequent calls to the TAOpenText function or the open function of any other Data Access Submodule, and will be used to close the file when access is complete. This allows the file to be accessed from multiple Data Access Submodules without reopening.
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Set other Options: Once the source document has been opened, set any other desired options. Most options will be set at this time and are identified by requiring a VTHDOC handle type.
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Open a Handle to Text Access: Using the document handle, TAOpenContent is called to obtain a content handle that identifies the file to the Text Access module. This handle will used in all subsequent calls to the Text Access functions.
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Retrieve the first Information from the File: Call TAReadFirst to read the first piece of information from the file. Note: this step may be repeated to reread the file.
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Retrieve other Information from the File: Repeatedly call TAReadNext, which will iteratively read through and process the file.
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Close the Text Access Handle: Call TACloseText to terminate the text access for the file. After this function is called, the text handle will no longer be valid, but the document handle may still be used.
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Close the Source File: DACloseDocument is called to close the source file. After calling this function, the document handle will no longer be valid.
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De-initialize DA: DADeInit is called to de-initialize the Data Access technology.
1.8 Copyright Information
The following notice must be included in the documentation, help system, or About box of any software that uses any of Oracle's executable code:
Outside In Content Access © 1991, 2014 Oracle.
The following notice must be included in the documentation of any software that uses Oracle's TIF6 filter (this filter reads TIFF and JPEG formats):
The software is based in part on the work of the Independent JPEG Group.