Figure 1.
Comparative imagery of saltmarsh captured at different scales with different platforms: satellite, UAV, field (satellite imagery: GoogleEarth).
Figure 1.
Comparative imagery of saltmarsh captured at different scales with different platforms: satellite, UAV, field (satellite imagery: GoogleEarth).
Figure 2.
Modified Tetracam Miniature Multiple Camera Array (Mini-MCA).
Figure 2.
Modified Tetracam Miniature Multiple Camera Array (Mini-MCA).
Figure 3.
Image data pre-processing: Sensor correction and radiometric calibration.
Figure 3.
Image data pre-processing: Sensor correction and radiometric calibration.
Figure 4.
Illustration of the effects of increased noise proportion: Original image, 5 % noise, 25 % noise
Figure 4.
Illustration of the effects of increased noise proportion: Original image, 5 % noise, 25 % noise
Figure 5.
Relative Monochromatic Response and Absolute Filter Transmission.
Figure 5.
Relative Monochromatic Response and Absolute Filter Transmission.
Figure 6.
Illustration of the effects of vignetting: Original image, image exhibiting the radial shadowing of vignetting.
Figure 6.
Illustration of the effects of vignetting: Original image, image exhibiting the radial shadowing of vignetting.
Figure 7.
Forms of lens distortion: original, barrel lens distortion, pincushion lens distortion.
Figure 7.
Forms of lens distortion: original, barrel lens distortion, pincushion lens distortion.
Figure 8.
Dark offset imagery from the six channels of the mini-MCA: single sample, average of 125 samples, standard deviation of 125 samples.
Figure 8.
Dark offset imagery from the six channels of the mini-MCA: single sample, average of 125 samples, standard deviation of 125 samples.
Figure 9.
Distribution of noise within dark offset imagery for all six channels of the mini-MCA (Exposure 1,000 μs).
Figure 9.
Distribution of noise within dark offset imagery for all six channels of the mini-MCA (Exposure 1,000 μs).
Figure 10.
Separation of bimodal condition within Channel 2 of the mini-MCA (Exposure 1,000 μs).
Figure 10.
Separation of bimodal condition within Channel 2 of the mini-MCA (Exposure 1,000 μs).
Figure 11.
Flat field subsample illustrating pronounced bimodal condition within each channel.
Figure 11.
Flat field subsample illustrating pronounced bimodal condition within each channel.
Figure 12.
Illustration of the limited capacity for periodic structure removal with dark offset subtraction.
Figure 12.
Illustration of the limited capacity for periodic structure removal with dark offset subtraction.
Figure 13.
Illustration of the temporal progression of shutter band noise present within all channels of the mini-MCA.
Figure 13.
Illustration of the temporal progression of shutter band noise present within all channels of the mini-MCA.
Figure 14.
Response of noise response to lengthening exposure: average, standard deviation.
Figure 14.
Response of noise response to lengthening exposure: average, standard deviation.
Figure 15.
Effect of corrective factor upon vegetation spectral profile.
Figure 15.
Effect of corrective factor upon vegetation spectral profile.
Figure 16.
Vignetting LUTs generated from all six channels of the mini-MCA.
Figure 16.
Vignetting LUTs generated from all six channels of the mini-MCA.
Figure 17.
Vignetting radial falloff for all six sensors of the mini-MCA.
Figure 17.
Vignetting radial falloff for all six sensors of the mini-MCA.
Figure 18.
Effect of exposure on quantisation, and subsequent effect upon the vignetting radial falloff.
Figure 18.
Effect of exposure on quantisation, and subsequent effect upon the vignetting radial falloff.
Figure 19.
Comparison of the rate of vignetting radial falloff in the presence/absence of a filter.
Figure 19.
Comparison of the rate of vignetting radial falloff in the presence/absence of a filter.
Figure 20.
Application of vignetting correction : Original uncorrected image, application of filterless LUTs, application of Filter LUTs.
Figure 20.
Application of vignetting correction : Original uncorrected image, application of filterless LUTs, application of Filter LUTs.
Figure 21.
Radial distortion of all six channels within the mini-MCA.
Figure 21.
Radial distortion of all six channels within the mini-MCA.
Figure 22.
Illustrative lens distortion map of channel 3 of the mini-MCA.
Figure 22.
Illustrative lens distortion map of channel 3 of the mini-MCA.
Figure 23.
Uncorrected true and false colour composite mini-MCA imagery.
Figure 23.
Uncorrected true and false colour composite mini-MCA imagery.
Figure 24.
Comparative dark offset performance between high and low efficiency filters.
Figure 24.
Comparative dark offset performance between high and low efficiency filters.
Figure 25.
Comparative dark offset performance between high and low efficiency filters.
Figure 25.
Comparative dark offset performance between high and low efficiency filters.
Figure 26.
Comparative band alignment illustrating subtle improvement due to lens distortion correction.
Figure 26.
Comparative band alignment illustrating subtle improvement due to lens distortion correction.
Figure 27.
Comparative true and false colour composites before and after sensor corrections.
Figure 27.
Comparative true and false colour composites before and after sensor corrections.
Figure 28.
Checkered condition within the mini-MCA giving rise to multiple radiance distributions.
Figure 28.
Checkered condition within the mini-MCA giving rise to multiple radiance distributions.
Table 1.
Filter Transmission/Monochromatic efficiency Correction Factors.
Table 1.
Filter Transmission/Monochromatic efficiency Correction Factors.
Filter (nm) | Transmission (%) | Correction Factor | Monochromatic Relative Efficiency (%) | Correction Factor | Multiplicative Correction Factor |
---|
450 | 0.44 | 2.28 | 0.16 | 6.25 | 14.27 |
490 | 0.47 | 2.13 | 0.34 | 2.97 | 6.32 |
530 | 0.47 | 2.12 | 0.56 | 1.80 | 3.81 |
550 | 0.45 | 2.21 | 0.62 | 1.61 | 3.57 |
570 | 0.44 | 2.26 | 0.67 | 1.49 | 3.38 |
670 | 0.56 | 1.80 | 0.91 | 1.10 | 1.98 |
700 | 0.56 | 1.79 | 0.93 | 1.08 | 1.92 |
720 | 0.51 | 1.96 | 0.95 | 1.05 | 2.06 |
750 | 0.49 | 2.02 | 0.97 | 1.03 | 2.09 |
900 | 0.48 | 2.07 | 0.71 | 1.40 | 2.90 |
970 | 0.47 | 2.14 | 0.45 | 2.22 | 4.75 |
Table 2.
Image Acquisition Details.
Table 2.
Image Acquisition Details.
Date | Site | Longitude | Latitude | Height (m) | Exposure (μs) |
---|
25/11/2012 | Ralphs Bay | 42 55.742′S | 147 29.036′E | 100 m | 4,000 |
Table 3.
Sensor Noise Characteristics.
Table 3.
Sensor Noise Characteristics.
Channel | State | Average | StDev | Skew |
---|
1 | 1 | 8.445 | 0.650 | −3.379 |
2 | 8.452 | 0.6817 | −2.987 |
2 | 1 | 1.828 | 0.884 | 1.559 |
2 | 15.972 | 0.670 | −23.798 |
3 | 1 | 6.999 | 0.317 | −18.182 |
2 | 11.981 | 0.504 | −23.543 |
4 | 1 | 9.374 | 0.626 | −5.627 |
2 | 14.974 | 0.628 | −23.801 |
5 | 1 | 7.757 | 0.542 | −5.664 |
2 | 5.527 | 0.747 | −1.094 |
M | 1 | 8.020 | 0.449 | −10.784 |
2 | 3.508 | 0.762 | 1.247 |
Table 4.
Lens Distortion Coefficients.
Table 4.
Lens Distortion Coefficients.
Channel | cx | cy | k1 | k2 | p1 | p2 | Fx | Fy |
---|
1 | 629.169 | 465.738 | −0.068745 | 0.0623006 | −0.000639335 | −0.000509879 | 1622.5 | 1622.5 |
2 | 628.961 | 464.003 | −0.0579649 | 0.0356426 | −0.000102067 | −0.00221439 | 1606.81 | 1606.81 |
3 | 632.575 | 472.777 | −0.0506697 | 0.021484 | 0.000077687 | 0.0011317 | 1625.74 | 1625.74 |
4 | 633.999 | 470.756 | −0.0912427 | 0.132531 | −0.000135051 | 0.00124068 | 1623.55 | 1623.55 |
5 | 632.498 | 470.568 | −0.0748613 | 0.0729301 | 0.000851022 | −0.000399902 | 1625.88 | 1625.88 |
M | 638.965 | 460.592 | −0.0922108 | 0.124107 | 0.000614466 | 0.000842289 | 1619.26 | 1619.26 |