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The upcoming cosmological surveys (LSST, Euclid, Roman, SPHEREx, etc) will map the universe with a wide angular and spectral coverage. Most of the studies with large-scale surveys rely on detecting individual sources, and leave the faint, diffuse components in the extragalactic background light (EBL) largely unexplored. To fully exploit the wealth of information from the upcoming cosmological survey datasets, we present two analysis techniques that directly extract cosmological and astrophysical signal from the multi-band large-scale EBL images without individual source detections. First, I will discuss cross correlation for EBL redshift tomography, and show prospects of constraining the EBL by cross-correlating SPHEREx and galaxy surveys. In the second part, I will introduce light cone analysis, a novel technique for analyzing the multi-band EBL images. Without cataloging individual sources, the light cone analysis uses a data-driven approach to simultaneously determine the spectral and spatial distribution of all emitting sources and the underlying large-scale structure traced by them. Our technique does not require any SED assumption and is not subjected to the source confusion as the conventional galaxy redshift surveys. This method will be widely applicable to upcoming cosmological surveys, and can provide complementary information to the galaxy detection approach.