mplayer GUI problems
 

Well, I installed mplayer and I tried and I got an error like PNG support required for GUI compilation, please install libpng and libpng-dev packages. I checked log and:
============ Checking for PNG support ============

#include <png.h>
#include <string.h>
int main(void) {
printf("png.h : %s\n", PNG_LIBPNG_VER_STRING);
printf("libpng: %s\n", png_libpng_ver);
return (strcmp(PNG_LIBPNG_VER_STRING, png_libpng_ver));
}

cc /tmp/mplayer-conf-6266-15467.c -o /tmp/mplayer-conf-1785-15467.o -lpng -lz -lm
/tmp/mplayer-conf-6266-15467.c:1:17: png.h: No such file or directory
/tmp/mplayer-conf-6266-15467.c: In function `main':
/tmp/mplayer-conf-6266-15467.c:4: error: `PNG_LIBPNG_VER_STRING' undeclared (first use in this function)
/tmp/mplayer-conf-6266-15467.c:4: error: (Each undeclared identifier is reported only once
/tmp/mplayer-conf-6266-15467.c:4: error: for each function it appears in.)
/tmp/mplayer-conf-6266-15467.c:5: error: `png_libpng_ver' undeclared (first use in this function)

ldd /tmp/mplayer-conf-1785-15467.o
ldd: /tmp/mplayer-conf-1785-15467.o: No such file or directory

Result is: no

Anyone know how I can fix this?

Install the libpng and libpng-dev packages like it says to do, and then try again. What distro are you using?