Snapshot compressive sensing refers to compressive imaging systems where multiple frames are mapped into a single measurement frame. Each pixel in the acquired frame is a linear combination of the corresponding pixels in the frames that are combined together. While the problem can be cast as a compressive sensing problem, due to the very special structure of the sensing matrix, standard compressive sensing theory cannot be employed to study such systems. In this work, two novel, efficient and theoretically-analyzable snapshot compressive sensing recovery algorithms are proposed. The algorithms are iterative and employ compression codes to impose structure on the recovered frames. The algorithms are validated in simulation results and their performances are shown to be comparable with the performances of state-of-the-art heuristic algorithms.