Under the SMAF specification, the Graphics Track represents data which expresses a sequence for display, and describes picture sequences that interact with display devices.
  In theory, up to 256 tracks can be displayed. However, in practice the number of tracks which can be displayed depends on the hardware being used to play back the SMAF data and on the nature of the content data.
  The explanation of the Graphics Track which follows is based on the prerequisite that there is only one Graphics Track. This is because, when the specification was first drawn up, it was assumed that there would only ever be one type of SMAF display device on which to play back files.
  The display device which is assumed for the Graphics Track is presumed to have many virtual planes. In the Graphics Track it is possible to describe a picture display sequence for any of these virtual planes. These picture sequences are referred to as Graphics Track sub-sequences. In any sub-sequence procedures are defined for displaying text and image data simultaneously, and also for erasing the text and image data.
  The resulting image, which was synthesized on a virtual plane, is displayed on a physical display device (such as a mobile device's LCD display panel). This summary of the specification also defines the virtual plane synthesis method. Based on data representation, it is only possible to specify an arbitrary maximum number of virtual planes -256. However, the following explanation assumes a three-plane implementation. (Of these three planes, one can be set to display the background color only.)

The structure of the Graphics Track is as described below.

• Header (required)
• Set-up Data Chunk (required)
• Sequence Data Chunk (at least 1 required)
• Font Data Chunk (optional, no more than 1)
• Image Data Chunk (optional, no more than 1)

The contents of the mandatory header are described below.
Format Type
Player Type
Text Encode Type
Color Type
TimeBase
Option Size
Option Data

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Format Type

Defines the data format for the graphics data used. At present, the "Handyphone Standard" is defined.

Player Type

Defines the class of the presumed playback environment. At present, the "Handyphone Standard" is defined.

Color Type

Defines the color code system used.

TimeBase

Defines the standard time used internally. TimeBase is the Graphics Track standard time for Duration, LifeTime and the like. The data used to express time is multiplied by TimeBase in real time.

Option Size

Specifies the size of extension data for future options.

Option Data

Specifies the extension data unit for Option Size (0~255 bits).

The contents of the mandatory Set-up Data Chunk are described below.

Display Parameter Definition Chunk
Used to define the display parameters of each characteristic display Event type.
Color Palette Definition Chunk
Not defined in detail

Sequence Data Chunk (at least 1 required)

Represents the display sequence. Coordinate values (numerical values designated in SMAF to represent coordinates) and Duration (a numerical representation designating parameters such as time or length) are used to represent sequence data. In addition, Events and Object Sub-blocks can also be specified.

Events

1. Short Control Event
   NOP Event
   Reset Origin Event
2. Control Event
   BackDrop Color Definition Event
   Offset Origin Event
   User Event
3. Display Object Event
   Ordinary Display Event

Object Sub-block

1. Primary Sub-block Text
   Bitmap
   Image
   Rectangle
   Text Block
   Image Tile
   Bitmap Tile
   
2. Auxiliary Sub-block
   Parameter override
   WipeTiming
   WipeSeq
   BannerInfo
   TravelSeq
   BlinkSeq
   ColorBlinkSeq
   Fill-InOutSeq

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Outline of SMAF Specification