A novel QIM data hiding scheme and its hardware implementation using FPGA for quality access control of digital image

This paper proposes a data-hiding scheme for quality access control of digital images using quantization index modulation (QIM) and its hardware implementation. To achieve the goal, an encoded binary message is embedded over N-mutually orthogonal signal points using the QIM technique but without complete self-noise suppression. It is well known that due to the insertion of external information, there will be degradation in the visual quality of the host image. This feature may be used in access control through the reversible process. At the decoder side, watermark bits are extracted using minimum distance decoding. Self-noise is then suppressed by the authorized user to provide a better quality of the image. Moreover, for real-time implementation, field-programmable-gate-array (FPGA) based hardware architecture is also proposed. The scheme is tested over a large number of benchmark images, and the experimental results are compared with the related scheme and found to be superior. It is also seen that (a) in real-time processing, the scheme saves 87.86% power than the related implementation found in the literature, (b) a very high throughput of 119.54 Megabyte/s and 119.048 Mbps are achieved for encoder and pipelined decoder at the maximum operating frequency of 120.013 MHz and 120.01 MHz, respectively for the processing of (512 × 512) sized images.