Data hiding called steganography is a security technique to protect secret data throughout the transmission from malicious attackers. The purposes of steganography are to obtain good stego-image quality, high embedding-capacity, low computational complexity, visual imperceptibility, undetectability, and more security. In this paper, we offer a new hybrid image steganography technique based on least significant bit (LSB) substitution and enhanced modified signed digit (EMSD) algorithms. The proposed algorithm utilizes n adjacent cover image pixels to hide the secret data with EMSD algorithm, and least significant k-bit for LSB substitution algorithm. Hence, it has more embedding capacity than the EMSD algorithm and exploiting modification direction (EMD) based algorithms. We obtain that the stego-image quality is better than 43 dB when the payload is 2.404 bpp. The results of experiment represent that this algorithm ensures high embedding-capacity while preserving acceptable visual stego image quality that can be undetectable by human eyes. Also, the hybrid of the EMSD and LSB substitution algorithms is to difficult for malicious people to consolidate data by scrambling secret data bits.

In this article, a new reversible data hiding method using most significant bits and center shifting technique in dual images is proposed. The proposed reversible data hiding method aims to securely hide high-capacity secret data. Instead of directly embedding the secret data, the method calculates new values with (n + 1) bits secret data and the n most significant bits of the cover image pixel values. Thus, it is impossible to extract secret data without obtaining the original cover image. Also, the center shifting process is performed to minimize the mean square error. After this process, the secret data to be hidden in the dual images are in the range $\left[-3\times 2^{\left(n-1\right)}+1, 3\times 2^{\left(n-1\right)}-1\right]$. The pixel values of stego images are obtained by using the secret data in this range value and cover image pixel values. As a result of experimental studies, when the payload is 2.5 bits per pixel (bpp), the peak signal-to-noise ratio value (PSNR), which expresses the visual quality, is above 34 (dB). In addition, the proposed method has proven secure against RS (regular and singular) analysis attacks.

The goals of image steganography are to simultaneously reach maximum embedding capacity, enhanced embedding efficiency, better image quality, and more security. We present a two-step data hiding method that improves image quality, capacity, and embedding efficiency, and also provides stego security. In the first step of the proposed method, the hidden data are encrypted with the key words and shifting method to provide security. In the second stage, we propose adaptive least-significant-bit (LSB)+3 type I and adaptive LSB+3 type II methods to hide encrypted data in the cover image. The image quality of the stego image obtained from the proposed adaptive LSB+3 method is better than the traditional three-bit LSB methods. When maximum data are embedded in the cover image, a peak signal-to-noise ratio (PSNR) greater than 41 dB is reached. Experimental studies show that adaptive LSB+3 type I and adaptive LSB+3 type II methods are higher PSNR values (3.48% and 5.73%) than the standard three-bit LSB substitution methods.

Yapılan çalışmada, ortamda bulunan nesnelerin gerçek zamanlı olarak tespit edilmesi, sınıflandırılması ve elde edilen sonuçlar sunulmaktadır. Önerilen yönteme ait deneysel çalışmaların gerçekleştirilmesinde fındık meyvesi kullanılmaktadır. Çalışma ortamında bulunan fındıklara ait görüntü, kamera ile alındıktan sonra görüntü işleme teknikleri kullanılarak işlenmektedir. Fındıkların görüntü düzlemi üzerinde kapladıkları boyut ve alan verileri hesaplanmaktadır. Elde edilen veriler değerlendirilerek, fındıklar gerçek zamanlı olarak üç sınıfa ayrılmaktadır. Bu işlem ortalama tabanlı sınıflandırma ve K-means kümeleme yöntemleri kullanılarak gerçekleştirilmektedir. Küme merkezlerinin belirlenmesi ve sınıflandırma işlemi fındık meyvesi verilerinden elde edilen bilgi veritabanı kullanılarak sağlanmaktadır. Çalışma ortamında bulunan fındık meyveleri, görüntü işleme teknikleri kullanılarak %100 başarımla tespit edilmektedir. Fındık meyvelerinin, ortalama tabanlı ve K-means kümeleme yöntemleri kullanılarak sınıflandırılması karşılaştırılmıştır. Karşılaştırma sonucunda, gerçeklenen iki yöntemin %90 ila %100 başarım oranında benzeştiği gözlenmiştir.