CLIF Metadata Format - VisionSystemsInc/voxel_globe GitHub Wiki

Columbus Large Image Format (CLIF)

CLIF Image

  • The image frames were taken simultaneously from a matrix of cameras.
  • The images are numbered with the camera (from 000000 to 000005) followed by a dash, followed by the frame number (e.g. 100000…)
  • There is a corresponding .txt metadata file for each set of 6 frames.
  • The text files describe the position and heading of the plane and have the following 14 data fields (comma separated one line files):
  1. Yaw - of camera head (in degrees)
  2. Pitch - of camera head (in degrees)
  3. Roll - of camera head (in degrees)
  4. Latitude - of camera head
  5. Longitude - of camera head
  6. Altitude - of camera head (in feet)
    • The latitude, longitude, altitude, roll, pitch, yaw form a vector that goes from the center of the camera head to the ground. The vector is based on a series of transformations in ENU (East, North, Up) space.
  7. imu time - gps time (in seconds) [For example, you can compute it's Monday at midnight but you'll have no idea which Monday it is. Counter starts on Sunday at midnight GMT. This is a NIMA string.]
  8. GPS week related to (7) [Tells you the week of the year, so now you know which Mon-day it is.]
  9. vNorth - IMU velocity in northerly direction
  10. vEast - IMU velocity in easterly direction
  11. vUp - IMU velocity in up direction
  12. imuStatus - Status of the IMU at the time the frame was taken
    • Below are the known GPS status codes:
    • 0 – GPS Locked
    • 1 – Insufficient Observations
    • 2 – No Convergence
    • 3 – Singularity
    • 4 – Covariance Trace
    • 14 – INS Inactive
    • 15 – INS Aligning
    • 16 – INS Bad
    • 17 – IMU Unplugged
  13. localAdj - time adjustment in hours between UTC and local time
  14. dstFlag - Flag indicating whether Daylight Savings Time was in effect (0 - No or un-known, 1 - Yes)
  • IMU_status is always equal to 3 (singularity)