Difference between revisions of "Eyesis4Pi data structure"

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==Images==
 
==Images==
 +
===Samples===
 +
[http://community.elphel.com/files/eyesis4pi/footage_samples/ Footage samples]
 
===Description===
 
===Description===
 
The pictures from each image sensor are stored in 8 triplets (because 3 sensors are connected to a single system board for the 24-sensor equipped camera) in the [[JP4|RAW JP4]] format.
 
The pictures from each image sensor are stored in 8 triplets (because 3 sensors are connected to a single system board for the 24-sensor equipped camera) in the [[JP4|RAW JP4]] format.
Line 54: Line 56:
 
|[[File:Eyesis jpeg.jpeg|thumb|200px|JP4 converted to JPEG - sample from the master camera]]
 
|[[File:Eyesis jpeg.jpeg|thumb|200px|JP4 converted to JPEG - sample from the master camera]]
 
|[[File:Eyesis vertical segment.jpeg|thumb|120px|Each triplet is a vertical segment]]
 
|[[File:Eyesis vertical segment.jpeg|thumb|120px|Each triplet is a vertical segment]]
|[[File:Eyesis_image_set.jpeg|thumb|500px|Eyesis4Pi images set]]
+
|[[File:Eyesis_image_set.jpeg|thumb|450px|Eyesis4Pi images set and their location on the result panorama]]
 
|}
 
|}
Each triplet when post-processed in ImageJ plugin, cut and re-oriented is a vertical segment of a panorama.
 
  
 +
===File names===
 +
Image filename is a timestamp of when it was taken plus the index of the camera ('''seconds_microseconds_index.jp4'''):
 +
<font size="2">
 +
1334548426_780764_1.jp4
 +
1334548426_780764_2.jp4
 +
...
 +
1334548426_780764_8.jp4
 +
</font>
  
===Images===
+
===EXIF headers===
 +
The JP4 images from the 1st (master) camera have a standard EXIF header which contains all the image taking related information and is geotagged. So the GPS coordinates are present in both the GPS/IMU log and the EXIF header of the 1st camera images. Images from other cameras are not geotagged.
 +
 
 +
* Open the [http://regex.info/exif.cgi?imgurl=http%3A%2F%2Fcommunity.elphel.com%2Ffiles%2Feyesis4pi%2Ffootage_samples%2F1334548258_780764_1.jp4 image from the master camera] in an online EXIF viewer.
 +
* Open the [http://regex.info/exif.cgi?imgurl=http%3A%2F%2Fcommunity.elphel.com%2Ffiles%2Feyesis4pi%2Ffootage_samples%2F1334548258_780764_2.jp4 image from the secondary camera] in an online EXIF viewer.
 +
* The coordinates can be extracted from the images with a PHP script and a map [http://community.elphel.com/files/eyesis4pi/other_files/map_points.kml KML file] can be created.
 +
 
 +
===Post-Processing===
 +
====Requirements====
 +
* [http://rsbweb.nih.gov/ij/download.html ImageJ]
 +
* [[Elphel_Software_Kit_for_Ubuntu#ImageJ_and_Elphel_plugins_for_imageJ|Elphel ImageJ Plugins]]
 +
* Calibration Kernels for the current Eyesis4Pi.
 +
 
 +
'''To be updated...'''
 +
 
 +
===Previewer===
 +
Here's [http://eyesisbox.elphel.com/panorama_preview/ an example of previewing the footage] (works better in Firefox).
  
 
===Links===
 
===Links===
 
* [[JP4|JP4 format]]
 
* [[JP4|JP4 format]]
 
* [[JP4_Compatible_Software| JP4 compatible software]]
 
* [[JP4_Compatible_Software| JP4 compatible software]]
 +
* [http://eyesisbox.elphel.com/panorama_preview/ Footage Preview]

Revision as of 14:04, 27 April 2012

Intro

Eyesis4Pi stores images and gps/imu logs independently.

Data Stored on Comments
Images Host PC or (9x) internal SSDs (if equipped)
IMU/GPS logs Internal Compact Flash cards (2x16GB)

IMU/GPS logs

Description

A sensor's log is a list of registered events from various sources:

  • Trigger for starting image exposure (fps)
  • IMU sentence received (2460 samples per second)
  • GPS sentence received (5 samples per second) - in NMEA or other configured format.

Logs are stored in a binary format to have smaller size. Also, there's a file size limit - when it's reached a new file with an auto-incremented index will be started.

Raw logs examples

All the raw *.log files are found here

Parsed log example

parsed_log_example.txt (41.3MB) at the same location

[localTimeStamp,usec]: IMU: [gyroX] [gyroY] [gyroZ] [angleX] [angleY] [angleZ] [accelX] [accelY] [accelZ] [veloX] [veloY] [veloZ] [temperature]

[localTimeStamp,usec]: GPS: $GPRMC,231112.8,A,4043.36963,N,11155.90617,W,000.00,089.0,250811,013.2,E

[localTimeStamp,usec]: SRC: [masterTimeStamp,usec]=>1314335482848366 [localTimeStamp,usec]=>1314335474855775

Tools for parsing logs

Download one of the raw logs.



Images

Samples

Footage samples

Description

The pictures from each image sensor are stored in 8 triplets (because 3 sensors are connected to a single system board for the 24-sensor equipped camera) in the RAW JP4 format.

JP4 file opened as JPEG - sample from the master camera.
Download original JP4
Open in an online EXIF reader
JP4 converted to JPEG - sample from the master camera
Each triplet is a vertical segment
Eyesis4Pi images set and their location on the result panorama

File names

Image filename is a timestamp of when it was taken plus the index of the camera (seconds_microseconds_index.jp4):

1334548426_780764_1.jp4
1334548426_780764_2.jp4
...
1334548426_780764_8.jp4

EXIF headers

The JP4 images from the 1st (master) camera have a standard EXIF header which contains all the image taking related information and is geotagged. So the GPS coordinates are present in both the GPS/IMU log and the EXIF header of the 1st camera images. Images from other cameras are not geotagged.

Post-Processing

Requirements

To be updated...

Previewer

Here's an example of previewing the footage (works better in Firefox).

Links