adjust brightness

Question

I want to change brightness but only colored pixel. (not white colors) How can I use c# this example image https://ibb.co/n8Z5L6

Željko Perić · Answer

Hello here is my solution for changing brightness value of pixels inside image. There are faster methods  read something about it at this url: https://www.codeproject.com/Articles/990093/Image-Processing-for-Dummies-with-C-and-GDI-Part // // // Bitmap Change_Brightness(Bitmap Image float brightness_value) { // // This method changes value // of pixel brigthness inside // passed bitmap image // // // Notice : // // Image format must be // JPEG or BMP standard 24 bits RGB format // // brighteness_value variable value range // goes from 0 (dark) up to 1 (bright) // // // For...Next..Loop trough out all pixels inside image // for ( int x= 0 ;x { for ( int y= 0 ;y { // // skip white pixels // if ( Image.GetPixel(xy).R != ( byte )255 || Image.GetPixel(xy).G != ( byte )255 || Image.GetPixel(xy).B != ( byte )255 ) // set new brightness value Image.SetPixel( x y Color.FromArgb( ( byte )(Image.GetPixel(xy).R * brightness_value) ( byte )(Image.GetPixel(xy).G * brightness_value) ( byte )(Image.GetPixel(xy).B * brightness_value) ) ); } } // // Return changed image // return Image; } // // // All the best Željko Peric