Dear Dnon Dnon,

The best metric of image quality is the human viewer, but there are many statistical measurements useful to use for comparison, such as:

Mean Squared Error (MSE)

Peak Signal-to-Noise Ratio (PSNR)

Structural Similarity Index (SSIM)

for more, see link

http://uk.mathworks.com/help/images/image-quality-metrics.html

Hi Dnon.

If you think about IQM measure more you can find in paper:

Nill, N., Bouzas, B. 1992. Objective Image Quality Measure Derived from Digital Image Power. Optical engineering, 31(4), pp. 813 – 825.

IQM, as well as, other image quality parameters (PSNR, MSE, SNR, RMSE) are tested in this this two papers.

Testing of Image Quality Parameters of Digital Cameras for Photogrammetric Surveying with Unmanned Aircrafts (2016)

https://www.researchgate.net/publication/311487225_Testing_of_Image_Quality_Parameters_of_Digital_Cameras_for_Photogrammetric_Surveying_with_Unmanned_Aircrafts

Increase of readability and accuracy of 3D models using fusion of close range photogrammetry and laser scanning (2012)

https://www.researchgate.net/publication/266210397_Increase_of_readability_and_accuracy_of_3D_models_using_fusion_of_close_range_photogrammetry_and_laser_scanning

Kind regards,

Mateo Gašparović