Audio Watermarking Algorithm with a Synchronization Mechanism Based on Spectrum Distribution

Figure 8

The extracted images about the second watermark. (a) Noise corruption (35 dB). (b) Noise corruption (20 dB). (c) MP3 compression (128 kbps). (d) MP3 compression (64 kbps). (e) Re-quantization. (f) Resampling. (g) Echo addition (100 s). (h) Echo addition (50 s). (i) Low-pass filtering(8 kHz). (j) Low-pass filtering (4 kHz). (k) Amplitude scaling (1.2). (l) Amplitude scaling (0.8). (m) TSM (−5%). (n) TSM (+5%). (o) TSM (−10%). (p) TSM (+10%). (q) PSM (−10%). (r) PSM (+10%). (s) Jittering (500). (t) Jittering (1000). (u) Random cropping (100). (v) Random cropping (200). (w) No attack.