public bool CheckNowEmbedded() { if (embeddedState_ != EmbeddedState.Embedded) { return(false); } embeddedState_ = EmbeddedState.Handled; return(true); }
/// <summary> /// Embed the text into the image. /// </summary> /// <param name="text">The text to embed.</param> /// <param name="bmp">The image to embed the text into.</param> /// <returns>The image containing the embedded text.</returns> public static Bitmap EmbedText(string text, Bitmap bmp) { // initially, we'll be hiding characters in the image EmbeddedState state = EmbeddedState.Hiding; // holds the index of the character that is being hidden int charIndex = 0; // holds the value of the character converted to integer int charValue = 0; // holds the index of the color element (R or G or B) that is currently being processed long pixelElementIndex = 0; // holds the number of trailing zeros that have been added when finishing the process int zeros = 0; // hold pixel elements int R = 0, G = 0, B = 0; // pass through the rows for (int i = 0; i < bmp.Height; i++) { // pass through each row for (int j = 0; j < bmp.Width; j++) { // holds the pixel that is currently being processed Color pixel = bmp.GetPixel(j, i); // now, clear the least significant bit (LSB) from each pixel element R = pixel.R - pixel.R % 2; G = pixel.G - pixel.G % 2; B = pixel.B - pixel.B % 2; // for each pixel, pass through its elements (RGB) for (int n = 0; n < 3; n++) { // check if new 8 bits has been processed if (pixelElementIndex % 8 == 0) { // check if the whole process has finished // we can say that it's finished when 8 zeros are added if (state == EmbeddedState.Filling_With_Zeros && zeros == 8) { // apply the last pixel on the image // even if only a part of its elements have been affected if ((pixelElementIndex - 1) % 3 < 2) { bmp.SetPixel(j, i, Color.FromArgb(R, G, B)); } // return the bitmap with the text hidden in return(bmp); } // check if all characters has been hidden if (charIndex >= text.Length) { // start adding zeros to mark the end of the text state = EmbeddedState.Filling_With_Zeros; } else { // move to the next character and process again charValue = text[charIndex++]; } } // check which pixel element has the turn to hide a bit in its LSB switch (pixelElementIndex % 3) { case 0: { if (state == EmbeddedState.Hiding) { // the rightmost bit in the character will be (charValue % 2) // to put this value instead of the LSB of the pixel element // just add it to it // recall that the LSB of the pixel element had been cleared // before this operation R += charValue % 2; // removes the added rightmost bit of the character // such that next time we can reach the next one charValue /= 2; } } break; case 1: { if (state == EmbeddedState.Hiding) { G += charValue % 2; charValue /= 2; } } break; case 2: { if (state == EmbeddedState.Hiding) { B += charValue % 2; charValue /= 2; } bmp.SetPixel(j, i, Color.FromArgb(R, G, B)); } break; } pixelElementIndex++; if (state == EmbeddedState.Filling_With_Zeros) { // increment the value of zeros until it is 8 zeros++; } } } } return(bmp); }
/// <summary> /// The method is called in the host process to tell the Sandbox that the Window has embedded. /// </summary> public static void NowEmbedded() { embeddedState_ = EmbeddedState.Embedded; }