###### simple example #########
$ echo -e "a b c d e\nf g h i j\nk l m n o\np q r s" | awk  '{ lines[i++]=$(NF-1) } END{ print lines[NR-3]  }'
i
###############################

###### mencoder output ########
[robert@phebehouse src] $ mencoder 2.mpg -quiet -ovc copy -oac pcm -o /dev/null 2>/dev/null
MEncoder dev-SVN-rUNKNOWN-4.1.3 (C) 2000-2007 MPlayer Team
CPU: AMD Athlon(tm) XP 2900+ (Family: 6, Model: 10, Stepping: 0)
CPUflags: Type: 6 MMX: 1 MMX2: 1 3DNow: 1 3DNow2: 1 SSE: 1 SSE2: 0
Compiled with runtime CPU detection.
success: format: 0  data: 0x0 - 0x355e800
MPEG-PS file format detected.
VIDEO:  MPEG2  720x480  (aspect 2)  29.970 fps  9000.0 kbps (1125.0 kbyte/s)
[V] filefmt:2  fourcc:0x10000002  size:720x480  fps:29.97  ftime:=0.0334
==========================================================================
Opening audio decoder: [liba52] AC3 decoding with liba52
AUDIO: 48000 Hz, 2 ch, s16le, 448.0 kbit/29.17% (ratio: 56000->192000)
Selected audio codec: [a52] afm: liba52 (AC3-liba52)
==========================================================================
videocodec: framecopy (720x480 24bpp fourcc=10000002)
a52: CRC check failed!
Writing header...
ODML: Aspect information not (yet?) available or unspecified, not writing vprp header.
Writing header...
ODML: Aspect information not (yet?) available or unspecified, not writing vprp header.
Writing index...
Writing header...
ODML: Aspect information not (yet?) available or unspecified, not writing vprp header.

Video stream: 2563.437 kbit/s  (320429 B/s)  size: 46337683 bytes  144.611 secs  4336 frames

Audio stream: 1536.000 kbit/s  (192000 B/s)  size: 27771904 bytes  144.645 secs
########################################
[robert@phebehouse src] $ mencoder 2.mpg -quiet -ovc copy -oac pcm -o /dev/null 2>/dev/null |  awk  '{ lines[i++]=$(NF-1) } END{ print lines[NR-3]  }'
awk: (FILENAME=- FNR=23) fatal: attempt to access field -1
########################################