Technical data

SightLine Applications Command and Control

***Values are calculated from internal tracking information. Multiple targets (either user-designated or

automatically-generated) are indicated. Pixel coordinates are in “display” coordinates suitable for

directly rendering over streamed digital video.

Sets the frame step rates at which KLV metadata is output. Per STD 0601, version identifier fields for

the UAS Local Data Set, Security Metadata Local Set, and Motion Imagery Track Metadata Local Set

are emitted with elements of each local set.

Set KLV Data (0x61)

Set KLV blob data constructed by user to be sent with H.264 stream. The KLV data will be sent along

with the next H.264 frame.

When you use this feature, you may want to disable the transmission of the built-in KLV metadata. You

can do that by setting Frame step to 0 using Set Metadata Rate (0x62) command.

Byte offset Description

2 KLV data length + 4 (if > 127, see below)

3 Optional high bits of KLV data length (if > 127, see below)

n Type = 0x61

n+1 Reserved (must be 0)

n+2 Reserved (must be 0)

n+3 KLV data start

... KLV data continued

The following is used to set the data length:

u16 len = KLV_Length + 4;

if(len<=127) {

data[2] = length;

data[3] = 0;

} else {

data[2] = (length & 0x7f) | 0x80;

data[3] = (length>>7) & 0xFF;

}

Example:

The following byte sequence is a packet with KLV data.

const unsigned char setKlvDataPacket[] = {

//TotalPacketLen=163, klvLen=155

0x51, 0xac, // Signature bytes

0x9f, 0x01, // Length (159 (0x9f) bytes: type(1) + reserved(2) + KLV(155) + checksum(1))

0x45, // Type (SetKlvData)