Topic: Multimedia. Compound documents. Object Linking and Embedding (OLE).

Purpose: To acquaint with the basic provisions related to the communication and implementation of objects. In this regard, introduce such a concept as multimedia.

Review questions

1.      What is Windows OS?

2.      What properties does the Windows operating system have?

3.      Why do we say Windows is an object-oriented environment?

New material

With the development of hardware and software, it became possible to combine objects of different origins, of different nature in one document - for example, text, photographs and music. Such documents are called composite documents. In this regard, we will introduce a new concept - multimedia.

Multimedia Is a special technology that allows using software and technical means to combine ordinary information (text and graphics) with sound and moving images (up to showing video films) on a computer.

In the broadest sense of the word, it can be considered that multimedia is a characteristic of software, hardware and information tools that combine different types of data in a single interactive environment. The ability of a user to influence the operation of a media is called interactivity. Interactivity distinguishes multimedia computing from other hardware and the execution and reproduction of complex documents.

In the narrower sense of the word, the concept of multimedia has stuck with hardware that allows you to reproduce sound (sound cards) and work with laser compact discs (CD-ROM drives).

Multimedia computer - a computer equipped with a sound card and CD-ROM drive. Almost all computers today are multimedia.

Multimedia software - a software package recorded on a CD-ROM, which includes multimedia data and programs for their playback.

Windows operating system has minimal tools for creating, processing and playing media files

We will look at what technique is used to create multimedia or simply compound documents.

The technique of creating compound documents is developing in two directions:

–        creating a powerful application focused on documents of a certain type (for example, texts), combining additional functions for working with other types of information (MS Word).

–        OLE (Object Linking and Embedding) - a technology for linking and embedding objects; Microsoft's standard for creating dynamic, automatically updating links between documents, or for embedding an object created in one application into a document that is being accessed by another application.

To explain the idea (I wrote a story (text editor) and inserted a picture (graphic editor) into it, then edited the inserted picture (returned back to the graphic editor without leaving the text editor)).

Benefits OLE technologies:

–        by introducing an object created in another application into an application document, we get not only a compound document, but they can also edit the object using the "native" application;

–        if you establish a link between an object and documents, you can save the object the ability to "live" its own life, serve other documents (save disk space).

OLE object is an arbitrary element created by means of any Windows application that can be placed (embedded and / or linked) into a document of another Windows application (it can be a fragment of a document, or maybe the whole document).

The application that creates the OLE object is called the OLE server (source application, source application).

An application that accepts an OLE object is called an OLE client (container application, receiver application).

Different Windows applications can support OLE to varying degrees. Some programs do not support it at all, some can only play the role of an OLE server (Paint, WordArt, Microsoft Equation, and others). Finally, there are the most powerful and versatile Windows applications (Word, Excel) that can execute the functions of both the OLE server and the OLE client.

Object embedding and linking

1 bd. Via the clipboard, using an application command from the horizontal menu Edit, Paste Special ... (you can embed or link a document fragment or the entire document); In this case, it is necessary:

1.      first open the source application and copy the required object;

2.      go to the container application, specify the insertion point and execute the command Edit, Paste Special ...

2 bd. Using the application command from the horizontal menu Insert, Object ... (only the entire document);

3 bd... In some cases, the command to paste the contents of the clipboard Edit, Paste plays the role of one of the Paste Special ...

Let's explain the difference between embedding and linking an object and embedding and inserting an object.

Implement you can either a fragment of a document, or the entire document (as a file). When injected, the object becomes part of the container document and loses connection with the original file. An embedded object can be edited using the OLE server, but the change is not reflected in the original file, and vice versa.

To tie with a container, only an object that is formatted as a document file can be used. When the file is modified using the OLE server, the changes are reflected in the container document (either automatically or at the user's direction).

Linking an object to a document is usually accompanied by embedding, in which case two copies of the object appear in the system (one in the container, the other in the source file). However, sometimes you can just bind an object without embedding it. In this case, only a link to the source file is placed in the container document.

Implementation - a special case of insertion. If the container application cannot register the fragment as an object of some application, the fragment is simply inserted as part of the document and can be further edited only by means of the receiving application.

Thus, a fragment can be inserted (but not embedded), but cannot be embedded without inserting.

In many cases, an embedded object can be thought of as an icon (pictogram). For example, a phonogram can be represented by some kind of visual picture, and then, by double-clicking on this picture, you can make the phonogram sound.

Questions to reinforce

1.      What is multimedia?

2.      What are the two directions in the creation of compound documents?

3.      What is OLE Technology?

4.      How are OLE client and server different?

5.      What is embedding and what is object linkage? What's the difference between them?