  Mid-infrared spectroscopy is often used to identify material. Thousands of
spectral points are measured in a time-consuming process using expensive
table-top instrument. However, material identification is a sparse problem,
which in theory could be solved with just a few measurements. Here we exploit
the sparsity of the problem and develop an ultra-fast, portable, and
inexpensive method to identify materials. In a single-shot, a mid-infrared
camera can identify materials based on their spectroscopic signatures. This
method does not require prior calibration, making it robust and versatile in
handling a broad range of materials.
