Eliminating plaintext video from external memory

Abstract

In an embodiment, an integrated circuit comprises a decompressor, an encrypt unit, and an on-chip image buffer coupled to the decompressor and the encrypt unit. The decompressor is configured to receive a compressed video stream, and to reconstruct a first frame of the video stream in the on-chip buffer. The encrypt unit is configured to generate one or more pixel block streams from pixel blocks of the first frame in the on-chip buffer according to sequence data describing an order of access of the pixel blocks to reconstruct subsequent frames of the video stream. The sequence data was previously generated via processing of the video stream by the integrated circuit, and the encrypt unit is configured to encrypt the pixel block streams to be written to an external memory. In an embodiment, an integrated circuit comprises a decrypt unit configured to decrypt an encrypted, compressed video stream; an on-chip buffer; and a decompressor coupled to the decrypt unit and the on-chip buffer. The decompressor is configured decompress the video stream, and to store a first portion of each of a first plurality of frames decompressed from the video stream in the on-chip buffer. The decompressor is further configured to store a remaining portion of each of the first plurality of frames in an external memory, wherein each frame as stored in the external memory is incomplete because the first portion is not stored in the external memory.