Personal View site logo
Make sure to join PV on Telegram or Facebook! Perfect to keep up with community on your smartphone.
Please, support PV!
It allows to keep PV going, with more focus towards AI, but keeping be one of the few truly independent places.
Official Low GOP topic
  • 1003 Replies sorted by
  • Thanks again Kae, Butt and everyone else.

    I'd take the Cinematographers settings over the Videographers settings any day of the week.
  • @Mimirsan
    Do check all your settings carefully, as many times when testing different settings I changed one little thing, the video laid down perfect while shooting but played back with the pulsing you describe.
  • Butt
    Im aware of the first few frames issue but this Its not the same its almost a continuous pulsing breakup and this image is a grab from around 1 min.
    Will try out your new settings when I get time.
  • @danyyyel

    Yea, from my understanding, less compression (shorter GOP) should mean less processing... but more data to move.

    I also suspect that most modern consumer cameras (like the GH2) probably have the ability to write compressed-RAW data for video... the companies just don't want this to happen because it'll mean the end of ALL their "professional" divisions.
  • @danyyyel

    interesting theory!!!
  • I am no expert, but I am asking myself if the Gop 3 is more about bandwidth than processing power. That we could achieve more with I frames that p or b frames because perhaps the architecture has changed. That is the bottleneck is more the processing power than the speed of the I/O of the gh2. It seems that it is a fact now that the gh2 has a much better controller to write to the SD card (From what I read) as with mjpeg reaching already in the 100+ megabit. Perhaps because of this it will be easier to get higher quality with the shorter gop where the processor has to calculate less. It is a bit like the red, which just take the raw data (even if it is mildly compressed) from the sensor and send it to the media. It requires vast amount of bandwidth but the debayering and intensive processing are done latter. I am not saying the same from the gh2 as the debayering is occurring but more I frame means less work for the processing engine. This is just a theory, I might be completely off.
  • @mimirsan

    I can not confirm,
    maybe you have the image of the junk at the beginning of the file
    one second (approx.) is always bad

    But tomorrow I test this new setting for 720p Edit: P1000420_kl.jpg is "old"

    edit July 24: the new Settings (including 1080/24pH GOP3 @kae) see seta.zip
    P1000420_kl.jpg
    1200 x 675 - 112K
    seta.zip
    478B
  • Butt
    Sadly the 720p setting of yours gives my image lots of macroblocking mud when static,moving,anything.
    See pic (look at stone cats face to see total lack of detail)
    image
    720p.jpg
    1280 x 720 - 344K
  • @kae
    You can post a setting on your favorite now Gop3 (set.zip) - thanks

    10:00pm
    have now both settings, @kae and @Butt side by side testet,
    result: I see no real difference - I prefer them on my setting - also because of slightly lower bit rate


  • Can't test anymore until Monday but wanted to post my latest 1080 24p settings. It seems just doubling the high/low-bottom/top settings provides better looking footage with bigger b frames than using a higher multiplier on those so I went back to my previous settings. These settings will give you up to 60Mb 1080 24P 3 GOP with approx. 58Mb on the death chart (little lower than the Extreme settings but I think this is because it's laying down bigger b frames so it's more efficient).

    I like these settings best so far, the motion is very crisp and the autofocus with the 14-140 is snappier than with the extreme settings. There are just basic 1080i/720p settings in this file which you can change at will. 720p GOP for Pal and NTSC is 6, NTSC 1080i GOP is set to 6 and Pal 1080i has be 3 because it's tied to 1080 24p. The 24h buffer settings may be redundant as Vitaliy proved above but I left them in.

    I do like these 1080 24p settings better visually than butt's latest settings but that's just a personal preference. At 60mbit the image and motion seems crisper with these and the data rate is definitely higher. Any testing would be appreciated.
    3GOP60MDeathChartKAEa.JPG
    1273 x 676 - 169K
    3GOP60MDeathChartKAE.JPG
    1265 x 668 - 172K
    setb.zip
    437B
  • @randolfo
    "Exaggerated?"

    What settinsg did you use for all i frame? looks incredible!! How's the motion look on the footage???
  • @Elenion
    You can download my settings: setb.Jpeg (post 12:55pm: download setb.zip!) use. is my setting for 72050p GOP3
  • Impressive achievements. I'm going to test 720p50 with low gop, do you have any suggestion?
  • ok vitaliy
    with my settings and pappasart death testchart

    P1070820_kl.jpg
    1200 x 674 - 82K
    P1070821_kl.jpg
    1200 x 674 - 80K
    P1070822_kl.jpg
    1200 x 674 - 82K
  • Guys, please do not turn topic into chat.
    You can always use edit to not make multiple posts, or send PM for personal question.
  • @randolfo

    GOP1 - the setting is?
  • @Kae

    Exaggerated?
    Schermata 2011-07-22 a 13.08.55.png
    1275 x 662 - 68K
  • @Butt

    Thanks, I try and let you know!
  • @Randolfo

    i love my setting still (edit 24.7.11: new Settings 1080/24p @kae; 1080p MJpeg @Butt; 720p by @kae and @Butt - see you new seta.zip)

    setb.zip
    482B
    seta.zip
    478B
  • @kae
    thanks kae - I will try your "setb"
  • @Kae

    What is currently your best configuration?
  • @kae
    "You have I frames at 1Mb, and all else is B frames only.
    Each references two low compressed I frames :-)"

    I think that's because in the screenshot's case I was shooting the codec crusher chart which was static and had no color info. The b frames probably didn't need to be bigger. Below, I've attached some night interior footage shot at 1080 24P 3 GOP with the same settings as above and you can see the B frames are larger as I was moving the camera a lot. The I frame didn't need to be as huge as it was a normal detail shot instead of the massively detailed codec crusher. I will try and take some higher detailed shots outside and see if I can get the 1mb I frames along with higher bit rate b frames.
    3gop60Mbit24PNightInterior3200isoA.JPG
    1264 x 668 - 168K
    3gop60Mbit24PNightInterior3200iso.JPG
    1273 x 652 - 171K
  • 24pN + Short GOP + Lower Quantization + High Bitrate ==> Nirvana? :)
  • @kae
    You have I frames at 1Mb, and all else is B framaes only.
    Each references two low compressed I frames :-)
  • Low light note: The above 3 GOP settings are yielding a very respectable filmic image at 3200 iso. Keep the shutter at 60 or above (50 didn't look as good to me) and the noise at 3200 iso looks a lot like film grain. It'll certainly do in a pinch.
This topic is closed.
← All Discussions