US Patent 10157184 Data previewing before recalling large data files

Techniques for providing data preview before recalling large data files are disclosed. In one aspect, a data file is made accessible while being offline by converting the data file from a native format to a preview format, storing the data file in the preview format in a primary storage that is locally available and moving, after the conversion to the preview format, the data file in the native format to a secondary storage. When a viewing request is received for the data file, the data file in the preview format is displayed to fulfill the viewing request.