Personal View site logo
Official GH2 "Stalin" hack development topic
  • 939 Replies sorted by
  • Does the MJPEG codec use 25 FPS or 30 FPS for PAL cameras?
  • @mpgxsvcd

    Hi mpgxsvcd... sorry to ask you a simple question- my GH2 is still in the mail! (Darn!) With the 2gig limit of MJPEG- do the files simply split and continue? (ie: no breaks?)

    As if there can be 4:2:2 (in future- I understand that this is being worked on)+ high bit rate- then really what else do you need??

    Cheers
    Alex
  • @alcomposer

    The files do not split. Right now I can only get about 1.5 minutes of footage with 1080p MJPEG before it hits the 2 GB limit. This is a fundamental element of the way MJPEG works so I doubt you will ever get around it.

    Right now there is no 4:2:2 option for the GH2 MJPEG and I question whether it is necessary or not for anything but green screen work. I have never been able to tell a difference between using or not using 4:2:2 with my hacked GF1.

    Ultimately, high bit rate 1080p is the answer because the compression is so much better. However, this might be a good way to get 1080p @ 25 FPS for PAL users if PAL cameras write MJPEG @ 25 FPS. Anyone know the answer to that? I am testing it with the NTSC to PAL setting now.
  • I get a "file number exceed limit" error message when I turn my camera from NTSC to PAL. Anyone know how to correct that? I formatted the memory card in the camera after I switched it to PAL.
  • @mpgxsvcd

    Turn camera off and back on.

    And please, make your own topic.
  • It appears that MJPEG is 30 FPS even for PAL cameras. Back to the drawing board.
  • @Vitaliy

    Thanks that worked. I will create a new topic.
  • are there any instructions on how to update the GH2 with ptools?
  • @mpgxsvcd
    "I have already got some completely stable 1080p @ 100+ mb/sec footage"

    Have you uploaded the settings anywhere? I wouldn't mind trying it out
  • yes please post the settings of the stable 1080p @ 100+ mb/sec footage @mpgxsvcd

    pretty pleae w/ a cherry on top.
  • @_gl @mrbill Please give me a scenario where conformed 24p is insufficient so we can be done with it, now that we've established it is widespread in industry and produces indistinguishable results.
  • @mpgxsvcd - i use the hack on the gf1 to film commercially underwater nature footage, due to the small footprint of the camera, the cheapness if the camera floods and the 100mbit 422 i can get out of it. without 422, stock houses like getty wouldn't accept dslr footage, so for some of us it is very usefull. niche i agree, but extremely usefull. so 422 is a priority for me over 24 p and other things, language, battery, etc. as i suspect for many professionals using the hacked cameras.
  • sparedog bro, I thought 422 was not possible with the GH2? I wish it was!
  • @proaudio4 - i dont think the verdict is out yet on that one. only time will tell.
    any thoughts on the percentage likelyhood of this, vitaliy?
  • @sparedog

    Is it more of a "They only accept video with these specs" kind of thing or is there an actual visible difference. I have never been able to see any visible difference at all. Does anyone have any side by side screen shots that show the difference. I would believe it if I saw it but I have never seen the difference myself.
  • @mpgxsvcd

    You're right that it's not obvious, but for keying it certainly helps.
  • @_gl
    Not trying to beat this dead horse any more...but in my prior life I was an audio guy for a number of years and currently write/compose/produce my own music outside of my regular space systems engineering job. When we ran our own studios one of our tasks was to do re-mixing of previously released material. Time compression was used successfully on 99% of the tracks with no hiccups. That was then...this is now.. and the technology is a great deal better and more readily available now.

    But I do understand the need for 25p in PAL country... no one is arguing that. My original point was that...there are alternatives today that work well.

    Note: I've never done this with movies myself. But if I did I wouldn't necessarily compress it all in one fail swoop. You can break that puppy down in several segments and stitch them all together (just a thought).
  • @Ian_T, I've replied in a PM so we can keep the thread clean.
  • @mpgxsvcd - no you are right, i cannot see a visible difference between 422 & 420 in anything i have ever shot or tested, rushes wise. as far as i know it is more of a safety margin with the stock houses incase the footage needs to be pushed quite far in the color grading. it does really help in that department. everything is graded before submitting, so if a client wants to regrade it, the 422 holds up much better.

    but for day to day non-broadcast i wouldnt worry about it for footage i shot if i knew i had no future market for it. i cant imagine anyone is going to visually (without scopes) look at footage with even a small amount of grading and say, that's 420 or 422.

    but the hack has done more for the cameras than just made them awesome prosumer tools. with the hack, they are also serious tools for high end professional projects and that should not be over looked, as it is extremely useful and cool.
  • [[[ On the question of the need for 25p, I'm curious - is the problem of syncing to lamp flicker for mains-driven lamps no longer relevant? ]]]
  • I am working on PTool, all is going normally.
    Main target now is improved usability for casual users, so all they'll need to do is use one simple patch for each thing.
    This requires some changes.
    Plus some parts will be totally new, like correct (almost :-) ) remaining time display for ACVHD modes.
  • Thanks, VK!
  • Thank you!