I'm currently trying to modify the code to get 20+ fps (was requested many times, but I had no time on this :( currently I'm on vacation, will try to implement it)
On Thu, Oct 24, 2013 at 10:02 AM, Alexander Brovman < alexander.brov...@gmail.com> wrote: > Maxim, > > Thank you for responding so quickly. The primary reason i asked is because > we sometimes need to output data like Financial Stock charts or similar > dynamic content and in a resolution size of 1650x1080. As you can imagine > right now the delay is.. manageable, perhaps somewhere along the lines of > 0.5-1 second delay id say. > We had an independant tested saying its an average of 130ms. But for fast > video/changes the framerate will sometimes drop or become laggy. > > Ill try setting the timebetweenFrames to 30ms which in "ideal" conditions > should give me 33.333 frames per second of video. > As for the Thread.Sleep(XXX) not working or functioning i will remove the > thread.sleep(60) from the top, > As for the Thread.Sleep(xxx) settings i will simply remove it; BUT i will > leave in the "Thread.sleep(Math.max(0, timeBetweenFrames - spent));" since > "worst" case scenario it will not be put to sleep at all since the output > will be 0, and "best case" scenario the thread will be put to sleep for 30 > - 1 ms depending on how the calculation turns out. > > Perhaps it would be good to leave somekind of thread sleep in there that > is a static factor, from a development standpoint i would rather prefer > having a fixed constant in there. rather than putting the thread to sleep > (potentially twice). Either that or im not understanding the reason for the > first thread.sleep (or the second one). > Either way i will make the changes now and compile, I will report my > findings here if you want me to :) > > @Sebastian, > > At the time of writing this i saw you respond, so i am writing this short > addendum: > 1) Could you please comment on whether or not Thread.Sleep(xxx) works? > 2) 2-4 frames per second and less may be great for static presentations > but not so much for dynamic. I understand the concerns raised on your > behalf regarding bandwidth usage but since we have a dedicated Gigabit > connection we have no issues with dedicating anywhere between 2-5 Mbit per > user. 20 Frames per second really is the minimum we are looking at, i think > it would be great if you presented people with an option/alternative to > gotowebinar. I understand that applications which compile into native code > will always be faster and outperform in certain aspects, but when you have > the motivation and perhaps the financial resources to dedicate time and > money into getting away from solutions such as GoToWebinar. > > Is there a way of "fixing" the position of the screen that the viewers > will see when they accept a desktop streaming broadcast from a presenter? I > ask this because i havent found a way to change the location of the Chat > Bar inside a conference room yet (neither have I found a way to change the > colors/themes to be honest, need to do some more google searches). > > Kind regards, > Alexander > > > > On Thu, Oct 24, 2013 at 4:47 AM, seba.wag...@gmail.com < > seba.wag...@gmail.com> wrote: > >> Do we still have the super high quality setting in the sharing client? >> My problems in the past was more around the bandwidth issues then the FPS. >> If you do 2-4 FPS the bandwidth usage will go that up... there is >> probably a trick, maybe there is also something todo in the way the tiles >> are calculated that need to be resend. It normally should only try to >> resend the ones that really change. So if you show an hd movie you might >> see your bandwidth needs go up quite a bit. >> >> Seb >> >> >> 2013/10/24 Maxim Solodovnik <solomax...@gmail.com> >> >>> Hello Alexander, >>> >>> Your findings are correct :) >>> With the only exception: Screenshots are taken in single thread, so >>> there are some limitations in the speed :( >>> I believe Thread.sleep(xxx) doesn't work at all >>> I'm planning to rewrite this part And hopefully will be able to increase >>> FPS. >>> >>> Basic compilation steps are here: >>> http://openmeetings.apache.org/BuildInstructions.html >>> After compiling all jars in screensharing folders are being signed, so >>> you need to replace all of them, otherwise you will get security error due >>> to different certificates >>> >>> >>> >>> On Thu, Oct 24, 2013 at 3:07 AM, Alexander Brovman < >>> alexander.brov...@gmail.com> wrote: >>> >>>> Hi, >>>> >>>> I have two quick questions, but first of all i just wanted to say that >>>> Openmeetings is fantastic. I had both OpenMeetings and BBB Installed and we >>>> have decided to go with OM. >>>> >>>> I am relatively apt at programming with Python and C# but I have never >>>> worked with a lot of Javaapplications like these ones, so i have the >>>> following questions: >>>> >>>> *1)* From what i understand the ScreenSharing is performed by taking >>>> snapshots every x milliseconds. Additionally there is an algorithm in place >>>> that divides the snapshot into tiles and measures the changes in tiles, if >>>> there is a change the tile is uploaded. If this is correct, and i want a >>>> more.. "fluid" video because there will be a lot of changes, cant i simply >>>> modify the "framerate" at which the images will be compared to improve the >>>> output? I am well aware that this would eat into the CPU and the bandwidth >>>> but i have a Full Duplex Gbit and 2x Quadcore Xeons available to me so this >>>> is not an issue. We are trying to test for an extreme case of 500-1500 >>>> users and how to optimize the output, i think the developers and other >>>> users will be interested in seeing the results. >>>> >>>> >>>> *2)* Where would these changes need to be made? So far i have isolated >>>> the CoreScreen.java , CaptureScreen.java and theScreenV1Encoder.java files >>>> that apparently contain the code which processes the desktop sharing. >>>> >>>> The CaptureScreen.Java has the: >>>> "timeBetweenFrames = (ScreenDimensions.quality == >>>> ScreenQuality.VeryHigh) ? 100 : 500;" setting on line 54 which basically >>>> says that if Screequality is set to very high (condition is true) then >>>> select 100 as the value for timeBetweenFrames. >>>> >>>> This variable is apparently used lateron in the >>>> "Thread.sleep(Math.max(0, timeBetweenFrames - spent));" on line 96, which >>>> will pause the current loop for the amountof time that is the difference >>>> between timeBetweenFrames( in our case 100ms) minus the spent time (which >>>> is defined on line 91). >>>> >>>> So in Theory if i wanted to output the screen in realtime at 20 or 24 >>>> frames per second which would mean that a snapshot would need to be taken >>>> every 50 milliseconds or so, would i simply need to set a different frame >>>> setting for the time between frames, something like: >>>> "timeBetweenFrames = (ScreenDimensions.quality == >>>> ScreenQuality.VeryHigh) ? *20* : 500;" >>>> >>>> Reduce the Thread.sleep(60); on line 60 to something like 20 >>>> milliseconds so (Thread.sleep(20);) >>>> and then finally remove the the last part "Thread.sleep(Math.max(0, >>>> timeBetweenFrames - spent));" or perhaps leaving it in? >>>> >>>> I understand that this would be a .. "wrench and hammer" approach since >>>> this will probably eat up quite a bit of CPU usage. I mean the simpler >>>> solution here clearly would be to get rid of the algorithm itself and >>>> simply rewrite it to simply output a screenshot every x milliseconds or so, >>>> but i have no idea how deep i would be messing with openmeetings and if >>>> that would/could break other parts of openmeeting that access these files? >>>> >>>> So would this be a workable solution that i could at least try out? I >>>> would ofcourse be more than happy to supply the CPU Usage differences. >>>> >>>> *3)* My only question would be is how would i recompile these? I am >>>> asking because i read somewhere in the mailinglists (or the old google >>>> groups) that it is recommended to use ANT in order to recompile things. >>>> Also what will be the output name of the .jar that is essentially being >>>> loaded for people and located on the server? >>>> Because all i can find on my Debian box is >>>> the >>>> /usr/lib/red5/webapps/openmeetings/screensharing/openmeetings-screenshare-2.1.1-RELEASE.jar >>>> file. >>>> >>>> So yeah, if somebody could help me with recompiling i would appreciate >>>> it! :) >>>> >>> >>> >>> >>> -- >>> WBR >>> Maxim aka solomax >>> >> >> >> >> -- >> Sebastian Wagner >> https://twitter.com/#!/dead_lock >> http://www.webbase-design.de >> http://www.wagner-sebastian.com >> seba.wag...@gmail.com >> > > -- WBR Maxim aka solomax
