NI 5431 Composite Video Generator
Generating a Customized Video Signal Using the Video Attributes

Intermediate Create Composite Signal from BMP Image is equivalent to Basic Create Composite Signal from BMP Image in Generating a Standard Video Signal, except that you can modify an arbitrary number of video attributes and insert digital synchronization patterns into the video data.

You can access this example VI by selecting Functions»Video Generation»Generator Examples»Intermediate create composite signal from BMP image.

You can modify video attributes, which are the parameters of the video signal. In the Intermediate create composite signal from BMP image VI, the Attribute List control is an array of clusters. Each element in the array corresponds to an attribute that you can modify. The clusters contain two simple controls on the front panel.

To modify the video attributes, complete the following steps:

1. Launch the VI.
2. Make sure the module ID control value matches the value assigned by MAX during configuration of the module.
3. On the front panel, use the operator tool and the up and down arrows on the Video type control to select the appropriate video format.
4. In the Attribute List control, click any one of the three Attribute controls that you want to modify, and choose the attribute by name. If you need to change more than three attributes, scroll down the array using the Index control on the left side of the Attribute List data array control.
5. In the Attribute List control, input the attribute values in the Value control. This example VI shows three default cases:
• Synchronization amplitude Sync amplitude (IRE) set to the value 40 IRE (the default for PAL/SECAM = 43; the default for NTSC = 40)
• Synchronization pulses duration Sync duration (µs) set to the value 4.7 µs (the default value for all video standards)
• Contrast factor Contrast set to the value 1.00 (the default value for all video standards)

When you select enable on the Digital sync control, the VI inserts four digital synchronization signals in order—composite sync (Csync), horizontal sync (Hsync), vertical sync (Vsync), and field identification (Field ID)—into the four least significant bits of the video data. The video data is created and/or saved as 16-bit data, but only 12 of these bits are used to generate the analog video signal. When you create the four digital synchronization signals, it does not affect analog signal quality.

The four signals can be accessed as standard TTL signals on the digital output connector of the NI 5431.

Note  To generate these signals, enable both the computation and the digital output of the NI 5431.

6. Run the VI. The Input BMP file? dialog box appears, prompting you to select a bitmap image file.
7. Double-click the BMPs shortcut to browse for the appropriate bitmap image file according to the video format you chose in step 3. Refer to Basic Examples for more information.
8. Double-click the appropriate subdirectory, then double-click a .bmp file.

Note  To avoid being prompted for the file, enter the bitmap image file path in Input BMP file path before running the VI.

After a few seconds, a video signal with the modified attributes generates on the output connector.