D-5(freemind: IP)

v-3.0
---
1. convert => png: RGB to RGBA

	==> done
D-5(freemind: IP)

v-4.0
---
1. merger png files
2. new func
    char ** _setup_FileName_Src(int, char **)
    void init_Row_Pointers_C(png_structp png_ptr, png_infop info_ptr)
    void _test_WritePng_Merge

	==> done
D-5(freemind: IP)

v-4.1
---
1. new func: void set_PixelVals(png_byte* ptr)

	==> done
D-5(freemind: IP)

v-4.2.0
---
1. save png C => no copying; just with background

	==> done
D-5(freemind: IP)

v-4.2.1
---
1. copy png A only

	==> done