Data Size Optimization

Once your exporter produces valid ACMI data, the next step is to review what is being recorded and how often. Telemetry files can grow quickly, and inefficient exports affect both storage and real time streaming performance.This page describes practical techniques to reduce file size without losing meaningful information: adjusting update frequency, removing redundant or low value properties, and tuning numeric precision to match the required fidelity. Even small adjustments can significantly reduce file size and network overhead, especially in scenarios involving many simultaneous objects.

Use the proper end-of-line character

Use \n as the end-of-line character instead of \r\n. This will save one byte per line, which can result in quite a lot of savings over time.

Avoid redundant data

Output new samples only when the corresponding data has changed. Tacview will smartly interpolate values.

Use longitude and latitude offsets when applicable

If your data is limited to a 10 x 10 degree of longitude/latitude sector, consider using ReferenceLongitude and ReferenceLatitude to reduce your coordinates size.

Tweak your samples resolution

Output only the relevant digits. Unnecessary trailing digits will just make the data stream bigger without providing any meaningful data. You may also want to write your own printf() function which does not output useless trailing zeros. This will also save a lot of bandwidth.

You should consider exporting your data with the following resolution. This will help to save bandwidth and storage space:

Property	Suggested resolution
# (frame time)	0.01 second (Tacview truncates samples time to 0.01 second for technical reasons anyway)
T (longitude/latitude)	0.0000001 degree (gives 0.011 meter resolution at the equator)
T (altitude)	0.01 meter
T (roll/pitch/yaw)	0.1 degree
T (flat coordinates)	0.01 meter
AGL	0.01 meter
HDG	0.1 degree
IAS	0.1 m/s

Tweak the export frequency by sample type

Perhaps the biggest optimization you can do, is to tweak your export frequencies depending on the type of object. The following export frequencies give a good balance between size and latency. They are used for the DCS World exporter. You should not export data more often than suggested in this array. You may lower the frequency further if your objects are always following smooth trajectories.

Object Type	Frequency
Player aircraft	10 Hz (and up to 16 Hz when remotely controlled by Tacview)
Weapon	8 Hz (for high roll objects like missiles and rockets)
Air	5 Hz (for air objects in general)
Projectile Bomb Decoy Shrapnel Ground	2 Hz (object with smooth ballistic trajectories)
All other objects	1 Hz