mencoder -of lavf -oac copy -ovc copy -o outputfile inputfile1 inputfile2 

MP4Box -cat inputfile1.m4v -cat inputfile2.m4v -cat inputfile3.m4v -new outputfile.m4v

avimerge -o outputfile.avi -i inputfile1.avi inputfile2.avi

mpgjoin inputfile1.mpg inputfile2.mpg inputfile3.mpg -o outputfile.mpg

First run

sfdisk -l -uS /mnt/sda1/rescuw.raw

to discover the offsets required for each partition. Multiply the offset by 512 and substitute it for BYTES below

mount -o loop,offset=BYTES -r /mnt/sda1/rescue.raw /mnt/rescue