Attributes Overview

To support binary compatibility, some of the SunVideo attributes that do not have particular applicability for SunVideo Plus are supported on a limited basis.

There are two methods for setting device attributes. The first method is to call the xil_device_create(3) and xil_device_set_value(3) functions prior to creating the device image with the xil_create_from_device(3) function. The second method is to call xil_device_set_value(3) after calling xil_create_from_device(3). Certain attributes require that they be set with the first method (such as DEVICE_NAME) and are documented as such in the following sections. See "Important Attribute Information" for addition information.

The following general device attributes are available with the MMACo1k device and are also supported by SunVideo:

• DEVICE_NAME

• FORMAT

• FRAME_NUMBER

• IMAGE_SKIP

• PORT_V

• MAX_BUFFERS

• PORT

• NUM_BUFFER

• FIRST_SCANLINE

• FULL_BUFFERS

• TIMESTAMP

• FLUSH_BUFFERS

• FORMAT_V

The following device attributes have no affect, but are either ignored or handled by SunVideo Plus in a reasonable way to support binary and source compatibility with SunVideo.

• MPEG_RATE_CONTROL

• MPEG_FIXED_QUANT

• MPEG_WEIGHTS

• FILE DESCRIPTOR

The following are SunVideo Plus video attributes:

• HUE

• H261_PIP

• CHROMA_GAIN_V

• CHROMA_GAIN_U

• BRIGHTNESS

• CONTRAST

• H261_BIT_RATE

• H261_MAX_QUANT

• H261_IBLOCK_REFRESH

• H261_FUR

The following sections describe the attributes in more detail. Note that some attributes are "set-only" and others are "get-only." This is noted under the ACCESS heading for each attribute. Some of these attributes are also parameters in the SunVideo Plus control panel. Although default values are given, the true default value is the value last made in either the control panel or by a previous XIL set attribute call. These attributes have an asterisk (*) before there DEFAULT entry. See "The SunVideo Plus Control Panel and XIL Attributes" for more information.