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Dear all, Several days ago, I posted How to write a bmp file pixel by pixel. Instead of bmp, I succeeded in writing a PPM file by using the pixmap package. Thanks for the hint generously provided by Uwe Ligges. Now I have a new question. How to convert a PPM file to BMP file in R? I know I can do this in photoshop or by some other softwares, but I think if I Can do this in R, that

Dear all, I open a bmp device by the bmp() function in the png package, but I don't know how to write color pixel by pixel into the file? Any help or hint? What I want to do is to create a 512*512 bmp file with certain dots being red and others black. I have all the pixel coordinates for the red dots, but I don't know how to draw the color on the device. Please help