SJ6 Legend Jerky Video

Discussion in 'SJ6 LEGEND' started by Robert Wells, May 29, 2017.

  1. Robert Wells

    Robert Wells New Member

    Joined:
    May 29, 2017
    Messages:
    1
    Likes Received:
    0
    Trophy Points:
    1
    Location:
    Chicago
    New SJ6 Legend, latest firmware. Image is good however video play back is extremely jerky making it un watchable.
    Every second there is a pause.

    Using Sandisk Pixtor Extreme 64 SD Card
    1080 60FPS
    Gyro on
    Distortion correction On

    Anyone have any ideas?
     
  2. Jon

    Jon New Member

    Joined:
    Jun 15, 2017
    Messages:
    7
    Likes Received:
    0
    Trophy Points:
    1
    Gender:
    Male
    Location:
    Philippines
    That is my problem also, Did you Experience also where you cannot use the 4k and 2k image?
     
  3. Troy

    Troy Administrator Staff Member

    Joined:
    Feb 28, 2017
    Messages:
    10,259
    Likes Received:
    10,081
    Trophy Points:
    1,000
    @Robert Wells @Jon
    How are you guys watching the video? Video playback issues can be any of a number of things.
    Things like, the resolution you are running the video in, coupled with the equipment you are watching it on; also, the source of the video like if it is streaming from your camera through a cable that's running to your computer; your video card; hardware acceleration on the playback device; codecs being used to decode the video being played.
    Tell us more, and maybe we can figure out where it is being "bottlenecked"

    -Troy
     
  4. Jon

    Jon New Member

    Joined:
    Jun 15, 2017
    Messages:
    7
    Likes Received:
    0
    Trophy Points:
    1
    Gender:
    Male
    Location:
    Philippines
    @Troy Thank you sir! but can you also addressed my issue where I cannot used the 4k or 2k video on sj6?
     
  5. Troy

    Troy Administrator Staff Member

    Joined:
    Feb 28, 2017
    Messages:
    10,259
    Likes Received:
    10,081
    Trophy Points:
    1,000
    Can you give us more details? Kind of difficult to guess what's happening without any details.
     
  6. sampath_sam

    sampath_sam New Member

    Joined:
    Jun 11, 2017
    Messages:
    7
    Likes Received:
    0
    Trophy Points:
    1
    Gender:
    Male
    Location:
    india
    its giving me jerky video on low light and night always no one answerin me??
     
    Last edited by a moderator: Jun 20, 2017
  7. Troy

    Troy Administrator Staff Member

    Joined:
    Feb 28, 2017
    Messages:
    10,259
    Likes Received:
    10,081
    Trophy Points:
    1,000
    If you have low light mode on, it's purpose is to gather more light by sacrificing unique frames in the set framerate (fps), so your current set FPS will be halved to allow in more time to expose those frames.
     
  8. Troy

    Troy Administrator Staff Member

    Joined:
    Feb 28, 2017
    Messages:
    10,259
    Likes Received:
    10,081
    Trophy Points:
    1,000
    Can you tell us what you mean by "cannot use"... you mean those 2 options are not available? That will be very odd. Show us a picture here so we could see if there is indeed a bug.
    It may, however, not function properly for you if your card is not fast enough to handle such high resolutions. Check your memory card, if it does not meet the minimum speed requirement, then that's where your problem lies.
    I suggest using a high speed Class 10 card, at least with a 90mbps write speed.
     
    Ken J likes this.
  9. Jon

    Jon New Member

    Joined:
    Jun 15, 2017
    Messages:
    7
    Likes Received:
    0
    Trophy Points:
    1
    Gender:
    Male
    Location:
    Philippines
    Hi sir,

    Sorry for the late reply, I am using a Scandisk 32Gb Memory card. I already figured out the problem. I uploaded the video on Facebook and its working well but not on my desktop since it will not display the video but only the audio. I guess sjcam is choosy when it comes to what media player it will play its video.

    Thanks for the reply,
    Jon
     
  10. kamkar

    kamkar Elite

    Joined:
    Jun 27, 2017
    Messages:
    134
    Likes Received:
    41
    Trophy Points:
    28
    Gender:
    Male
    Location:
    Denmark
    I have just recorded a 9 hour long video with my Sj 6 legend ( using 1080/30 - narrow FOV and distortion correction on - high bitrate )
    And i have no problems with it on my computer.

    Intel(R) Core(TM) i7-3770K CPU @ 3.50GHz
    RAM 32768MB
    OS Windows 10
    Memory card Trancend premium 400X 128 Gb

    Player what ever it is windows 10 have, but also VLC and other players work too.

    OBS. i do have a codec pack installed, but really that should not be needed with the pretty standard format my SJ cameras output, but you guys might want to give that a try.

    Memory cards are victim of a lot of faking, i will only buy mine ( and i have a lot as a action and dashcamera tester ) from a local source or from a EU amazon.
    I will not finger any brand but in dashcams it seem that sandisk are not so popular though some use them just fine, and i have had a lot of kingston cards die on me but i had nothing but kingston at one time, and the replacement cards all seem to have been working good as it have been a while since i had a kingston die on me.

    Brands i have.
    PNY
    Kingston
    Lexar
    Trancend
    Toshiba
    Looking for:
    Samsung cards.

    Most SDXC class 10 - U1 - but i am only buying class 10 - U3 cards now

    PS. i have off course also recorded with other resolutions on my Sj 6 legend, and those work fine for me too.
    PPS. And my 9 hour recording it should have been made with 1080/60, so will have to do that for my next recording like that ( journey log )
     
    Troy likes this.
  11. Troy

    Troy Administrator Staff Member

    Joined:
    Feb 28, 2017
    Messages:
    10,259
    Likes Received:
    10,081
    Trophy Points:
    1,000
    @kamkar
    That's awesome! Very informative, should be a thread of its own.
    One question though, would you care to elaborate why you are now favoring U3 cards over those that are lower?
    These insights are very helpful! Keep going :)
     
  12. kamkar

    kamkar Elite

    Joined:
    Jun 27, 2017
    Messages:
    134
    Likes Received:
    41
    Trophy Points:
    28
    Gender:
    Male
    Location:
    Denmark
    The memory cards are often the reason of erratic behavior in cameras, but as people have managed to upload and been able to see fine footage from that place then it must be a computer issue and not a camera issue.
    And you will be amazed how many people run pretty weak computers, either cuz age have passed by or they like my friend got a cheap office computer and then expect it to be able to play the latest games.
    But there are vast differences in the hardware between a good computer made for office work and a good computer build for gaming.

    And often you will see people having a lot of things open and then playback of a video file just make the house of programs tumble, so it is a good idea to try and shut down things that might be running in the background.

    So in this case people should try shutting down other things they might have running, or try to download and install a codec pack ( free )
    And for the love of god dont play the footage from the camera connected to the computer, copy the footage to your computer first or put the memory card in a good card reader on a fast USB port ( USB 2.0 or USB 3.0 or higher )

    While cameras like this can function like a mass storage devise you will often find copying footage from it that the speed you can get off the camera are pretty low, way less than the fast memory card you might have in the camera.
    Now for copying a Gb or 2 of data, sure just use the camera like mass storage, but if you have a full 32 Gb memory card the 5 - 10 MB/s speed you get off the camera in mass storage mode will be way less than the 20 - 90 MB/s ( depending on card ) you would get off the card in a good card reader.
    And it is in this case the U3 cards with the high read speeds are nice cuz copying 32 Gb to your computer with 90 MB/s are a lot faster than doing the same with 10 - 20 MB/s speed.

    Regarding me now favoring class 10 / U3 cards.
    Well to be honest it is a bit silly by me for a couple of reasons.
    1: where the class 10 / U3 cards really differ from class 10 / U1 cards are in the write speed, you will often see write speeds on U3 cards around 80 - 90 MB/s, and a good class 10 / U1 have a write speed of around 20 MB/s ( megabytes / second not to be confused with the bitrate of footage that is Megabit / second )
    And even the nice SJ 7 star recording 4K footage in the highest bitrate and image quality will only write something like 5 MB to your memory card every second, so a card that can do 80 MB/s are just a huge overkill.
    2: so i have been saying well in my card reader ( USB 3 card reader ) i then get full speed, and that is true, but when i have taken the card out of my camera and put it in my reader to review the footage well then i only read the footage either to see it or move it to one of my hard drives, and in that case the 90 MB/s of a U3 card is also silly cuz that read speed you can also get from a good U1 card.
    3: so like i said above the one place where the fast class 10 / U3 cards really matter now is when moving a lot of data from the card to the computer using a card reader that can give you the full speed of what ever memory card you have.
    But again its mot much larger speeds in read a U3 card have over a good U1 card.

    But if you look on prices on U1 and U3 memory cards ( same size / brand ) you will often see the U3 cards are not substantially more expensive, and the U3 card are more future proof so to say, your good U1 card will be of no use if you upgrade to a kick ass camera or maybe down the road a 8K camera.


    The definition for a Class 10 / U1 are ( minimum ) 10 MB/s sequential write speed, for a class 10 / U3 it is 30 MB/s

    The Toshiba cards i have are class 10 / U3 ( the cheapest 128 Gb cards here ) but their write speed are only like 30-40 MB/s but that's still within the standard defining the U3 class.
    Other U3 cards i have are 80 - 90 MB/s write speeds so they are well within the specs for the U3 class of cards.
    Some new memory cards are now marked with V?? this new V class are also relating to write speed so my really fast U3 cards are V90 cards.
    Learn more about memory card speed classes here.
    https://www.sdcard.org/developers/overview/speed_class/

    But to shorten things down you only need a good class 10 / U1 or V10 / V30 card for "regular dashcams and most action cameras on the market, you should only really need one of the really fast Class 10 / U3 or V60 / V90 cards ( there are new cards out with over 100 MB/s speeds ) if you use things like the gopro 5 and other expensive action cameras with ultra high bitrates ( 100 mbit or higher ) or if you run a 360 degree VR camera.

    No matter what camera you have you can always do a test recording to see what speed your camera offload data at.
    What i always do is set the camera to record 3 minute segments ( a habit from dash cameras ) then record a full 3 minute segment in full daylight.
    SO lets say your resulting 3 minute file are 900 MB large, so take 900 and divide that with 120 ( seconds / 3 minutes ) and you will get 7.5 so this mean for that recording your camera have written to the memory card with 7.5 MB every second.

    But there are one issue here regarding cameras, and that is there are 2 kind of bitrates that determine how large the output file will be ( resolution also have a say off course )

    1: VBR this is Short for Variable Bit Rate, in short int mean if your camera use or are set to VBR then the bitrate are not constant, so if your camera are VBR and you record in low light then you will find that the bitrate are small as you dont really need a high bitrate for night footage as there are little for the sensor and prosessor in the camera to work with.
    Same go if you record something where there are little movement in the footage, this will allso trigger VBR to select a lower bitrate,, so VBR save space on the memory card.

    2. CBR this is short for Constant Bit Rate, so as you can guess this mean the bitrate are locked in and will not change no matter the light level or action going on in the footage.

    People messing with MP3 files might also know bitrate or sampling rate, the higher bitrate on a MP3 file the better sound quality and so also a larger MP3 file.


    Traps people fall in.
    MB/s Vs mb/s or Megabytes / second Vs megabits/ second, so people see that this camera are 40 mbit and so they think they need a memory card that can do 40 megabytes / s
    You will also often see this misunderstanding with people talking about their internet speed, i have a 100 / 100 Mbit cable connection, but sadly that's not 100 megabytes i can transfer every second, it is only 8 - 10 megabytes or so every second.

    So it is a good idea to know your bits from bytes, it is confusing at times even for experienced users and personally i wish they would rename one of them to flippelflarp / second as that would kill off that issue.
     
    Last edited: Jul 27, 2017
    Eric Shepherd likes this.

Share This Page