This paper presents two JPEG steganographic methods using quantization index modulation (QIM) in the discrete cosine transform (DCT) domain. The two methods approximately preserve the histogram of quantized DCT coefficients, aiming at secure JPEG steganography against histogram-based attacks. In comparison with F5 as a representative JPEG steganography, the proposed methods show high performanc...

In this paper, we propose a hardware architecture of realtime JPEG encoder for 1.4 mega pixels CMOS image sensor SoC which can be applied to mobile communication devices. The proposed architecture has an efficient interface scheme with CMOS image sensor and other peripherals for real-time encoding. The JPEG encoder supports the baseline JPEG mode, and processes motion images of which resolution...

JPEG compression is a commonly used method of lossy for digital images. The degree can be adjusted by the choice quality factor QF. Each software associates this value to quantization table, which an 8 x matrix quantize DCT coefficients image. We propose recovering table relying only on image information, without any metadata from file header; thus proposed applied uncompressed format detect pr...