Created using

for f in */*.dv; do d=$(ffprobe -show_streams $f 2>/dev/null|grep duration=|head -1|cut -d= -f2|cut -d. -f1); if [ $d -gt 300 ]; then echo $f $d; fi; done


day1/makercon-11.dv 1639
day1/makercon-15.dv 846
day1/makercon-19.dv 1339
day1/makercon-21.dv 1105
day1/makercon-25.dv 2598
day1/makercon-30.dv 1548
day1/makercon-32.dv 1386
day1/makercon-35.dv 1355
day1/makercon-36.dv 559
day1/makercon-40.dv 971
day1/makercon-42.dv 593
day1/makercon-45.dv 995
day1/makercon-46.dv 518
day1/makercon-47.dv 2079
day1/makercon-4.dv 367
day1/makercon-51.dv 599
day1/makercon-55.dv 1406
day1/makercon-5.dv 1585
day2/makercon-15.dv 501
day2/makercon-17.dv 1587
day2/makercon-19.dv 884
day2/makercon-2014-10-18T110146.dv 1503
day2/makercon-2014-10-18T113210.dv 1207
day2/makercon-2014-10-18T13:07:30.dv 1646
day2/makercon-2014-10-18T13:38:34.dv 1450
day2/makercon-2014-10-18T14:03:26.dv 1127
day2/makercon-2014-10-18T15:02:30.dv 1609
day2/makercon-2014-10-18T15:30:55.dv 1510
day2/makercon-2014-10-18T15:59:44.dv 1370
day2/makercon-2014-10-18T16:24:57.dv 403
day2/makercon-2014-10-18T16:36:31.dv 775
day2/makercon-2.dv 520
tape/dvgrab-00:31:52:18.dv 1838