I downloaded the all-codecs package and extracted the files to /usr/lib/codecs which I assume is the default folder for the codecs as I installed Mplayer through an RPM.
In the GUI version, I tried to open the flv file. Among the list of supported files .flv was not present.
Anyway, I tried running it through the command line. This is what I got.
MPlayer 1.0pre2-3.2.2 (C) 2000-2003 MPlayer Team
CPU: Intel 3208 MHz (Family: 8, Stepping: 3)
Detected cache-line size is 64 bytes
CPUflags: MMX: 1 MMX2: 1 3DNow: 0 3DNow2: 0 SSE: 1 SSE2: 1
Reading config file /etc/mplayer/mplayer.conf: No such file or directory
Reading config file /home/thezealicon/.mplayer/config
Reading /home/thezealicon/.mplayer/codecs.conf: Can't open '/home/thezealicon/.mplayer/codecs.conf': No such file or directory
Reading /etc/mplayer/codecs.conf: Can't open '/etc/mplayer/codecs.conf': No such file or directory
Using built-in default codecs.conf
font: can't open file: /home/thezealicon/.mplayer/font/font.desc
Font /usr/share/mplayer/font/font.desc loaded successfully! (206 chars)
Linux RTC init error in ioctl (rtc_irqp_set 1024): Permission denied
Try adding "echo 1024 > /proc/sys/dev/rtc/max-user-freq" to your system startup scripts.
Using usleep() timing
Can't open input config file /home/thezealicon/.mplayer/input.conf: No such file or directory
Can't open input config file /etc/mplayer/input.conf: No such file or directory
Falling back on default (hardcoded) input config
Opening joystick device /dev/input/js0
Can't open joystick device /dev/input/js0 : No such device
Can't init input joystick
Setting up LIRC support...
mplayer: could not connect to socket
mplayer: No such file or directory
Failed to open LIRC support.
You will not be able to use your remote control.
Playing Rin to Sesshoumaru.flv
Exiting... (End of file)