Difference between Oprofile results and Perf results running the same use case

Hi,
I would like to profile my system when running my own application , so for that purpose I used Oprofile and also Perf tool. I run separately Oprofile and Perf with the same use case (same application and same duration).
When using Oprofile, I configured opcontrol with --event=CPU_ CYCLES:100000:0:1:1 and for perf , I used -c 100000 to be sure that both tools are sampling with the same event counter.
When generating results for each tool, I noticed a difference in the percentages. Below are results generated with Perf:

# Events: 362K cycles
#
# Overhead  Samples            Command
# ........ ..........  ...............
#
    31.40%     113991         kthreadd
    31.12%     112975          swapper
    11.96%      43418          dvbtest
     7.31%      26539     SE-Aud-Mixer
     4.34%      15750      kworker/0:1
     3.33%      12070            klogd
     3.31%      12033          syslogd
     2.57%       9327   irq/140-vsync0
     1.12%       4058             perf
     0.90%       3258      kworker/1:1
     0.55%       1990   irq/141-vsync1
     0.39%       1414   INF-EvtAsyncCb
     0.35%       1270      rcu_preempt
     0.31%       1108        VIB-Hpd/0
     0.21%        768      ksoftirqd/0
     0.19%        688             sshd
     0.14%        498            udevd
     0.11%        416            pkill
     0.11%        403     kworker/u4:0
     0.04%        138       INP-FE-IP1
     0.04%        136       INP-FE-IP0
     0.03%        127       INP-FE-IP5
     0.03%        121       INP-FE-IP2
     0.03%        118       INP-FE-IP3
     0.03%        107     ICS-Watchdog
     0.03%        106       INP-FE-IP4
     0.03%        101  VIB-HdmiRxMonit
     0.01%         40             init
     0.00%         11      ksoftirqd/1
     0.00%          8            dtach
     0.00%          6          rpcbind
     0.00%          2         ICS-Nsrv
     0.00%          2              :36
     0.00%          1        ICS-Admin
and here after results generated with Oprofile :

CPU_CYCLES:100000|
  samples|      %|
------------------
  1492238 76.8928 vmlinux
   230774 11.8914 libc-2.14.1.so
   107878  5.5588 dvbtest
    55578  2.8639 player2
    16198  0.8347 oprofiled
    15934  0.8211 mme
     7958  0.4101 stmcore_display_stiH407
     3226  0.1662 ics
     1975  0.1018 libpthread-2.14.1.so
     1547  0.0797 sth264pp
     1155  0.0595 ksound
     1107  0.0570 libcrypto.so.1.0.0
      899  0.0463 stm_event
      832  0.0429 syslogd
      466  0.0240 klogd
      445  0.0229 ld-2.14.1.so
      428  0.0221 strelayfs
      416  0.0214 bash
      378  0.0195 stm_wrapper
      238  0.0123 stlinuxtv
      206  0.0106 stm_registry
      182  0.0094 stm_pixel_capture
      140  0.0072 displaylink
      131  0.0068 stm_memsrcsink
      101  0.0052 stm_fe_ip
       52  0.0027 sshd
       37  0.0019 vibe_os
       24  0.0012 hdmirx_stiH407
       22  0.0011 libprocps.so.1.1.0
       22  0.0011 osdev_abs
       20  0.0010 ophelp
       15 7.7e-04 gawk
       15 7.7e-04 udevd
        6 3.1e-04 libnss_files-2.14.1.so
        4 2.1e-04 pkill
        3 1.5e-04 grep
        3 1.5e-04 sleep
        3 1.5e-04 libm-2.14.1.so
        3 1.5e-04 init
        2 1.0e-04 libgcc_s-4.8.2.so.1
        2 1.0e-04 libresolv-2.14.1.so
        2 1.0e-04 libpopt.so.0.0.0
        2 1.0e-04 libtirpc.so.1.0.10
        1 5.2e-05 rm
        1 5.2e-05 seq
        1 5.2e-05 libbfd-2.23.2.so
        1 5.2e-05 libgmp.so.10.1.3
        1 5.2e-05 libwrap.so.0.7.6

My focus is on "dvbtest" application. As you see in the results, Oprofile shows 5.558% against 11.96% with Perf.
Why results are so different?

PS: I used Oprofile 0.97 version, because it's the version available in the environment where I have to test and could not use the versions later.

Regards,

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