Soroor Ghandali1,∗ and Shih Yu Chang1
Soroor Ghandali
1Department of Applied Data Science, San Jose State University, San Jose, CA, USA
*Corresponding author
Linear factor models (LFMs) provide a principled framework for discovering low-dimensional latent structures underlying high-dimensional multimedia data. This paper presents a mask-aware Expectation-Maximization (EM) formulation for estimating LFM/factor-analysis parameters when different images, or different image patches, have different missing-pixel locations. The probabilistic latent-variable model itself is classical; the contribution of this work is an explicit image-oriented estimation and recovery workflow in which the observation masks are used in both the E-step and a row-wise M-step. In particular, each pixel’s mean, loading-row parameters, and diagonal noise variance are estimated only from samples where that pixel is actually observed. The paper also clarifies the relationship to EM-FA, EM-PCA, probabilistic PCA, and matrix-completion methods, specifies a low-rank implementation of the observed-data likelihood, and provides a reproducible experimental protocol including initialization, stopping criteria, random-mask generation, classifier specification, repeated trials, and factor-ranking stability checks. Experiments on Camera Man patches and MNIST handwritten digits characterize reconstruction quality and classification accuracy under increasing missing-pixel ratios, with repeated random-mask and initialization trials reported as means and standard deviations. Latent-factor indices are interpreted only after component alignment and stability assessment across random initializations.
Multimedia data recovery, linear factor model, factor analysis, expectation-maximization, missing pixels, latent representation
Soroor Ghandali and Shih Yu Chang (2026). Multimedia Data Recovery and Latent Factor Analysis. Journal of Networking and Network Applications, Volume 6, Issue 2, pp. 67–73. https://doi.org/10.33969/J-NaNA.2026.060203.
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