Hidden QIM Watermarking on Compressed Data Using Channel Coding and Lifting

This paper investigates the scope of application of channel coding on compressed host data for watermarking using dither modulation (DM) based quantization index modulation (QIM). Lifting based wavelet is used to decompose the encoded compressed data in integer coefficients. The relative gain on imperceptibility and robustness performance are reported for direct watermark embedding on entropy decoded host, using repetition code, convolution code, and finally the combined use of channel codes and lifting. Simulation results show that 6.24 dB (9.50 dB) improvement in document- to-watermark ratio (DWR) for watermark power at 12. 73 dB (16.81 dB) and 15 dB gain in noise power for watermark decoding at bit error rate (BER) of 10(-2) are achieved, respectively over direct watermarking on entropy decoded data.