Lossless manipulation of JPEG in C++

Question

I have a JPEG file on disk which is not quite normal - this JPEG file has additional rubbish data appended behind End Of Image (FFD9). This JPEG file can still be opened by JPEG viewers though.

I wish to remove those additional information behind End Of Image (FFD9). The constraints are:

1. Must be done programatically
2. Must be lossless
3. Must use native code, eg C++

One way I've found out is to re-save the file using IrfanView command-line tool, using lossless JPG_TRANSFORM's command: /jpg_rotate. The additional data behind are automatically stripped off.

However, is there another way in which I can do it in C++ code, If possible, I do not wish to use exes like IrfanView to do it. I wish to do everything in code to keep things lean.

I am thinking of detecting the End Of File (FFD9), then save the buffer before EOF into another JPEG. But, how can I save the buffer losslessly?

Answer 1

I guess this is a file handling question and NOT an Image Processing related.

All you need to do write all data till EOF in your Image file into the resultant Image file.