Slow mo jitter

When I add slow motion (or fast motion) to a SD PAL clip it looks fine when playing from the timeline but when rendered as Mpeg2 ready for dvd burning the clip jitters. I try to keep the speed control to whole ratios of the 50i frame rate. Any thoughts?
Richard Knight

Colin,
You are most likely correct, and the layout of the sequence settings
dialog does suggest that. However, I have seen enough variation in
export time and quality depending on whether a sequence is nested, or
whether Dynamic Link is in use, to be very careful with how I set that
option. So I explicitly set it on every object that is involved in the
export, including the main sequence and any nested sequences.
For example: below are the times for a 1+49 sequence when going from HD
1080i to SD 480i, using 2-pass VBR MPEG2-DVD encoding:
A. Export the HD sequence, no MRQ anywhere: 3+57
B. Export the HD sequence, MRQ on for the HD sequence and the AME: 15+19
C. Nesting the HD sequence in an SD sequence and exporting the SD
sequence, MRQ on everywhere: 37+50
Quality is noticeably better with each increase in render time.
Theoretically, there should be no difference in time or quality between
B and C. But there is. And so I am very careful when I set up my exports.
-Jeff

Similar Messages

Make my system slow after sync...

After I installed software update (Magic Trackpad support) in my 2.93 GHz/4GB Ram macbook pro, after I plugged my iP 3G and sync with itunes, my whole system will slow down , even I switch other windows / programs even click the tools bar, it will appear color wheels. and the sync progress takes 2-3 times long than before.
Even I ejected the iphone and unplug it, the system still slow and jitter, Is anybody have the same problem ? and how to fix it ? thanks

vikramkg wrote:
Hi
if i increase the memory will the system become faster.
No. Installing RAM doesn't make a computer faster.
Can we get it done this in Apple store
Sure, but why pay for that when you can do it yourself.
without upgrading hte memory cna we make this ystem to run faster ?
Have you checked activity monitor to see if any apps or processes are takin up a large percentage of the CPU?

When chane the clip speed it's jitter and shakes

hi
i want to ask about speed change
i use final cut 7 and when i change speed the clip it jitters and shakes
but the same clip i change the speed finat cut 6 it does not jitter
can anybody help me
i tried all known methods but i can not resolve the problem
i use hd 1920*1080 i apple proress 422 hq codec and my sequence settings and clips the same codec. even i take the clip to a blank sequence fcp asks me this is not match. changege sequence settings to match the clip settings? i sayt it ok and now my sequence and clips are same codecs. however the clips when i play them revers or slow it jitter.
field dominance is none. not upper or lower and sequence filed dominance is none too. i tried to change video processing options and render options but the same result.

Well, you haven't answered any of my questions. It's certainly not an issue with codec or format, so you've wasted a lot of time there.
As I have no idea what you mean when you say jitter, it's impossible for me to say what is causing it. Are you using Frame blending? What is the source of this video? Refer to my last post and see if you can answer some of the questions.
Patrick

Overclocking causes jitter in Premiere playback, slows Adobe Media Encoder

I was doing some overclocking on my system last night in order to test the limits. I found some strange results while encoding in Media Encoder and playing back in Premiere. Things actually got worse not better.
When my system was clocked to the defaults video playback was smooth in the preview window and while encoding a segment I checked the log to see how long it took. After the overclocking procedure the video picked up a slight tick or jitter on playback. Media encoder also took about 20 per cent longer to encode the same material? Any ideas? I've noticed people complaining about jitter on playback and being told to overclock to correct the problem. I think some timing issue might be causeing some systems to jerk.
My system:
AMD Phenom II X6 1090T Black Edition
Asus M5A88-V (AM3+)
Memory is 16GB GSkill (2-2x4) at 1666Mhz.
Video: EVGA nvidia GTS 450 hacked into the "support" list.
Things run fine at 232x16, 3.712 Ghz and also slower at 3.2Ghz
but when I did a little performance boosting my Passmark Rating sure went up (>8710) but these other things went slower (or ticked) when I thought they should have been going faster.
I notice the problem at 205X20, 4.11 GHz, voltage 1.476.
What have I done wrong?
~m

Are you talking about the PassMark Rating or the CPU Mark? I guess CPU Mark, and not System Mark. The Phenom is just too slow to achieve such a System Mark IMO.
FYI, the best Phenom II X6 1090T comes out at rank # 329, bested only by 328 Intel systems and the bulk of the AMD systems come out between rank # 400 and # 750. See Benchmark Results
I think that by overclocking you are overly stressing your disk I/O system, causing it to skip sectors and introducing latency on reads for playback. I would just reduce your overclock to something that plays back smoothly, since you will not notice any performance degradation with such a CPU.

Very slow since Mavericks, but also pg jitter/won't stay "docked" - trys to go to dashboard without a request to do so -- is anyonle else having this problem??

Ever since I installed Mavericks , it has caused the screen/page to jitter/float - and the mouse won't work until it "settles down" - usually about 30 seconds - -- many times a day...:( - It seems like it is trying to go to the Dashboard/ shaking and jittering in that direction...???
I called Apple care a couple of times about this, but they couldn't figure it out -- and now I am out of contract with apple care. - Anybody have any suggestions?? - Any help would be appreciated.

Somebody clearly hasn't read the User Guide.
Basic troubleshooting steps are retart, reset, restore from backup, restore as NEW.
If you have tried ALL of these steps and you're still having problems, then you need to bring your phone into Apple for evaluation.

WIFI Packet Loss/Jitter MacBook Air 11 & LION OSX 10.7.1

I started using computers more than 30 years ago when I was 5, I had my first IBM PC at the age of 10 and have never had any interest in paying over the odds for an Apple mac mainly because I saw the Mac as a kind of "Can't open nothing", one mouse buttoned retard of the computer world.
That is, until now.
I set up an online business 3 years ago and rented a dedicated server and set the whole business up in a cloud, so to speak. Having done that, all I needed a laptop for was a remote desktop connection and to run a SIP phone (Internet phone).
My PC based laptops had almost nothing installed on them, and I wasn't using software on the laptop itself, I was using remote desktop, so - why not try a MAC? The new Macbook Air 11 is small, light and made of metal and glass so should be robust enough to travel with me.
I have to say, this was the worst move I've ever made.
I opened the new shiny macbook and the first thing I noticed was that the internet seemed hit and miss. Moving around the room I managed to find a spot whereby pages woud load quickly. Strange, my £200 acer laptop was sh.t fast everywhere in the house. No matter, I packed it back away and carried on working on the Windows machine.
I've come to Newquay this week, and i've started to try and use the Macbook again in a hotel. The wireless signal in the room is low, and speedtest shows about 1 meg down and 3/4 meg up. That may sound bad to you, but remote desktop uses about 5k/sec (modem dial up speed) and the softphone, well, my Asterisk VOIP setup is confugured to use the GSM codec so that's 8k/sec each way + overheads.
This whole setup was deliberately designed to be "thin" so I can travel with ease and work on bad connections like USB internet sticks.
Anyhow, the Macbook was unable to hold a stable connection to the remote desktop or SIP phone, even though the speed test showed a whopping 1 meg up and down. What you may not be aware of is that there is more to a connection than the speed, there is the quality as well. How many packets are lost / how much "jitter" is on the line.
Anyhow, we're not living in the 3rd world, I ran a PINGTEST and it showed a small amount of jitter but told me the line was class B, online games may suffer but voip should be fine.
I unpacked the Acer, placed it in exactly the same spot as the Apple had sat in and it worked beautifully with 1 bar of wireless signal, all day long. Phone calls were clear.
So you know now what I'm thinking. I'm sitting here with my £200 acer because I can't use the £1500 macbook air 11. I paid nearly sixteen hundred pounds for this piece of .... and it doesn't ...... work. Time to contact Apple support.
2nd Mistake!
Representitive 1: - Told me that I can't compare the Macbook Air to the Acer, the Acer has Google Chrome and everybody knows Google Chrome is the fastest browser. I was told there was nothing more he could do, its probably a bad line at the hotel. When I explained the Acer works fine for voip I was told well, maybe it is getting a better signal. I explained the Acer has the cheapest possible parts inside it and paid 1500 for this macbook, expecting it to have quality parts inside and was told I'd paid for the size, because its so small but its not considered "powerful". Apple do you train your staff? Clearly not.
Thank god I wasn't paying to talk to this moron.
Representitive 2: - Had no idea what packet loss or Jitter was, got me to do a speedtest and said that looks fine. Then he got me to remove the WIFI adapter and re add it in the network settings.
Guess what, nothing changed, its still the same hardware and software.
Representitive 3: - Still not really understanding "quality" issues with the networking interface, I was asked to install the latest Java client. I did it, only because I wanted to comply with Apples wishes so they'd help me, but they weren't helping and Java has nothing to do with the network adapter, so that was useless advice too.
Apple seem to have no idea there is a problem, even though Google has pages and pages of people saying the same as me, and their own discussion forums have thousands of people complaining https://discussions.apple.com/thread/2664670?start=0&tstart=0
Finally, late yesterday whilst speaking to d.ck head number 3 at Apple support, we found a forum post talking about a fix, 10.7.1 update. I told d. head number 3 about the update and he suggested I applied it. So I did and everything looked great, for a whole evening.
This morning, I switched on again and the same thing, slow remote desktop, choppy unusable phone. Remember the phone needs less than 20k for a conversation, thats 0.2 meg. Speedtest again showing a whole meg both ways.
I called apple support again, this time being a little forceful, and I've asked for this to be escalated, but the bottom line is - they have no fix, they don't aknowledge this as a problem and I was told LION is new, so maybe it's got a bug..
I told the guy on the phone this is a network driver issue, the intermittency of the problem shows that and the Apple's lack of settings for the network adapter means the unit is autonegotiating with the router and choosing speed and duplex settings on its own. Sometimes it does that correctly, other times not and the connection although fast has a lot of noise / packet loss / corruption.
I've found a workaround, you put the unit to sleep and wake it up again and it runs fast until the next shutdown. Not really acceptable seeing as I was paying for "the cream of the crop".
I will definately not be recommending Apple products, and i'll certainly not be replacing the Windows laptops in my business with Apple's toytown system- i'd go out of business if I had to rely on this.
All there is left now, is to look at Boot camp and see if I can wipe this waste of space linux hack from the unit and install Windows 7.

I started using computers more than 30 years ago when I was 5, I had my first IBM PC at the age of 10 and have never had any interest in paying over the odds for an Apple mac mainly because I saw the Mac as a kind of "Can't open nothing", one mouse buttoned retard of the computer world.
That is, until now.
I set up an online business 3 years ago and rented a dedicated server and set the whole business up in a cloud, so to speak. Having done that, all I needed a laptop for was a remote desktop connection and to run a SIP phone (Internet phone).
My PC based laptops had almost nothing installed on them, and I wasn't using software on the laptop itself, I was using remote desktop, so - why not try a MAC? The new Macbook Air 11 is small, light and made of metal and glass so should be robust enough to travel with me.
I have to say, this was the worst move I've ever made.
I opened the new shiny macbook and the first thing I noticed was that the internet seemed hit and miss. Moving around the room I managed to find a spot whereby pages woud load quickly. Strange, my £200 acer laptop was sh.t fast everywhere in the house. No matter, I packed it back away and carried on working on the Windows machine.
I've come to Newquay this week, and i've started to try and use the Macbook again in a hotel. The wireless signal in the room is low, and speedtest shows about 1 meg down and 3/4 meg up. That may sound bad to you, but remote desktop uses about 5k/sec (modem dial up speed) and the softphone, well, my Asterisk VOIP setup is confugured to use the GSM codec so that's 8k/sec each way + overheads.
This whole setup was deliberately designed to be "thin" so I can travel with ease and work on bad connections like USB internet sticks.
Anyhow, the Macbook was unable to hold a stable connection to the remote desktop or SIP phone, even though the speed test showed a whopping 1 meg up and down. What you may not be aware of is that there is more to a connection than the speed, there is the quality as well. How many packets are lost / how much "jitter" is on the line.
Anyhow, we're not living in the 3rd world, I ran a PINGTEST and it showed a small amount of jitter but told me the line was class B, online games may suffer but voip should be fine.
I unpacked the Acer, placed it in exactly the same spot as the Apple had sat in and it worked beautifully with 1 bar of wireless signal, all day long. Phone calls were clear.
So you know now what I'm thinking. I'm sitting here with my £200 acer because I can't use the £1500 macbook air 11. I paid nearly sixteen hundred pounds for this piece of .... and it doesn't ...... work. Time to contact Apple support.
2nd Mistake!
Representitive 1: - Told me that I can't compare the Macbook Air to the Acer, the Acer has Google Chrome and everybody knows Google Chrome is the fastest browser. I was told there was nothing more he could do, its probably a bad line at the hotel. When I explained the Acer works fine for voip I was told well, maybe it is getting a better signal. I explained the Acer has the cheapest possible parts inside it and paid 1500 for this macbook, expecting it to have quality parts inside and was told I'd paid for the size, because its so small but its not considered "powerful". Apple do you train your staff? Clearly not.
Thank god I wasn't paying to talk to this moron.
Representitive 2: - Had no idea what packet loss or Jitter was, got me to do a speedtest and said that looks fine. Then he got me to remove the WIFI adapter and re add it in the network settings.
Guess what, nothing changed, its still the same hardware and software.
Representitive 3: - Still not really understanding "quality" issues with the networking interface, I was asked to install the latest Java client. I did it, only because I wanted to comply with Apples wishes so they'd help me, but they weren't helping and Java has nothing to do with the network adapter, so that was useless advice too.
Apple seem to have no idea there is a problem, even though Google has pages and pages of people saying the same as me, and their own discussion forums have thousands of people complaining https://discussions.apple.com/thread/2664670?start=0&tstart=0
Finally, late yesterday whilst speaking to d.ck head number 3 at Apple support, we found a forum post talking about a fix, 10.7.1 update. I told d. head number 3 about the update and he suggested I applied it. So I did and everything looked great, for a whole evening.
This morning, I switched on again and the same thing, slow remote desktop, choppy unusable phone. Remember the phone needs less than 20k for a conversation, thats 0.2 meg. Speedtest again showing a whole meg both ways.
I called apple support again, this time being a little forceful, and I've asked for this to be escalated, but the bottom line is - they have no fix, they don't aknowledge this as a problem and I was told LION is new, so maybe it's got a bug..
I told the guy on the phone this is a network driver issue, the intermittency of the problem shows that and the Apple's lack of settings for the network adapter means the unit is autonegotiating with the router and choosing speed and duplex settings on its own. Sometimes it does that correctly, other times not and the connection although fast has a lot of noise / packet loss / corruption.
I've found a workaround, you put the unit to sleep and wake it up again and it runs fast until the next shutdown. Not really acceptable seeing as I was paying for "the cream of the crop".
I will definately not be recommending Apple products, and i'll certainly not be replacing the Windows laptops in my business with Apple's toytown system- i'd go out of business if I had to rely on this.
All there is left now, is to look at Boot camp and see if I can wipe this waste of space linux hack from the unit and install Windows 7.

Severe Jitter/Glitches with Audigy Value/SE in Windows 7 64bit

Hello all,
Im experiencing a severe sound jitter and random "clicks" in windows 7 when playing music and using the computer for browsing.
I didnt notice this problem before because i used to keep my computer idle while doing other stuff when playing music.
the sound plays as if it "slows down" or something when doing random activities on the computer
My setup is
Intel Core 2 Duo E6550
4GB DDR2 800 MHZ
Creative Sound Blaster Audigy Value/SE
Windows 7 64BIT
Gefore 8880GT
I use winamp for playback.
Im using the latest drivers from the creative site.
Is there anything I can do?
The sound so

Thanks for the reply jmacguire.
I'm using default values: 6 bit, 48000 hz (DVD Quality)
Which one do you recommend with the SB Audigy SE?
The sound distorts when listening music in youtube or other flash webpages, both in normal and in HQ settings.
I have tried almost everything. I think the drivers downoladed for Windows 7 works better.
Then the Autoupdate function downloaded some new drivers (version .0090 I think) and it screwed up the sound on the web.

Video FX- fast/ reverse/ slow problems?

Why is it that when i slow down the speed of a clip, it seems to jitter/ shake just a bit? Is that how it is supposed to happen.. Shouldnt the movement be smooth?
Thanks!

We wish!
At 29.75 pr 25 fps iMovie has to show each clip for a bit longer than normal, hence the jitter.
Professional slow motion is shot with a high speed camera, perhaps as much as 10,000 fps. Played back at 25fps gives the slow motion effect.

2.2 is slower - for certain types of processing

So far the only major complaint I have with 2.2 is that it's slower for certain things. Scrolling through pictures in the camera app is slower. With 2.1 the pictures would show up immediately even when scrolling through them very fast. Also the grid view would load much faster, now i see a blank gray picture for 3-5 seconds before the actual photo loads. Scrolling through my contact list and app list is slower and choppy. Before it was fast and smooth.
Has anyone else noticed these types of issues? Could the amount of processes running in the background cause the "jitter" during processor intensive usage? With 2.1 I had the bare minimum running in background - maybe 2 - 4 processes and never had any issues. Now, I've disabled ATK - which seemed to help battery life, because of the wonderful programs that auto-restart themselves (such as Amazon MP3, footprints, skype, VZ Navigator, FM Radio, etc...), and have 10-20 processes at most times.

w40d1n1 wrote:
I believe that the froyo sluggishness, of the browser (pgup/down while the browser is still loading images), image viewer, and contacts, is due to the new "keep everything running in memory, and we'll sort it all out (by consuming more cpu) when the resources get low and froyo has to start killing/swapping apps to make room for the current app you are using" theory.;-)
actually it requires less CPU power to do it the Android way. It requires more processes force closing apps then then openning up what you want. Once a application is in memory it has 0 processes unless you are using it. If it uses a process then it is collecting data, or doing something you want it to do.
Everytime someone say Task Killers are needed still can't differenciate between process and application under the terms of Linux. I really do find it funny though. You NEVER hear people stating you need a Task Killer for OSX, Ubuntu, Fedora, or <insert linux variant here>, but always recommend it for Android eventhough it is a Linux Variant itself.

[WinXP/LabView7.0]Reading parallel port is too slow...

Hi,
First I would like to apologize for my English. I'm from Switzerland....
I'm trying to read out a 16Bit A/D in 1us steps. Serial Communication over a PIC is too slow, so I was looking for a faster option. I found out there is possibility to read from the parallel port:
I downloaded and installed the AccessHW drivers. I found 2 Vi's (see attached files) to read and write to the port. But this works only very slow. (100Hz read frequency).
By the way I need some advice how to use 16 bits in minimum as inputs. When I set the bit 5 in Baseregister+2 I can read the Baseregister. I can read the whole byte except bit 3. This bit stays always high (3.4 VDC).
The 5 status bits from Baseregister+1 I can
read with no problems but the read frequency is around 100Hz too...
The 4 control bits from Baseregister+2 I can't access. I followed the instructions in this link: http://zone.ni.com/devzone/conceptd.nsf/webmain/72C6FC6CE4AD4D1386256B1800794596?opendocument#4 to make this 4 bits inputs, but it doesn't work. I set the Baseregister+2 00100100 (all of the 4 bits are high) and then I start to read out the Baseregister+2, but there are no changes, when I connect one of the 4 pins to ground.
Hope there is anyone who can help me..!
Greets
Attachments:
Input_Byte_From_Port.vi ‏20 KB
Output_Byte_To_Port.vi ‏12 KB

If you're trying to acquire a 16-bit sample at 1MS/s, using the parallel port, it will not work. In fact, many full-fledged DAQ cards do not support this high sampling-rate/resolution combination. Look at what NI has available here, in the S and E series DAQ boards--this should give you a feel for what's out there and what a professionally manufactured piece of equipment is capable of:
http://sine.ni.com/apps/we/nioc.vp?cid=10955〈=US
http://sine.ni.com/apps/we/nioc.vp?cid=1038〈=US
As you noted already, a parellel port is going to be extremely slow for your needs, and likely not only be slow, but also have a pretty fair amount of timing jitter, since the timing of your read calls will be indeterminate. I would definitely recommend you look into som
e other hardware acquisition option besides your parallel port... it won't get you very far unfortunately, because that isn't what it's really designed for.

WriteMultiSamplePort is slow

Using WriteMultiSamplePort() (in C# and .NET3.5) to output an array of ints to the 4 digital output lines of a USB-6211 is very slow. (It's thankfully a lot faster than my first attempt, which used WriteSingleSampleSingleLine() in nested loops .) The ints are output at the rate of approximately 1 per millisecond and I need it to go much faster than this - maybe 100x or 1000x faster. I've googled and found mention of Task.Timing.ConfigureSampleClock(), but as far as I can see this applies to Analog I/O and I don't see a way to make it affect Digital Outputs.
Even the NI example code WriteDigPort.2008 only does 1 int per millisec.Can anyone help, please? If you can show me how to make the C# NI example go faster I can transfer the idea to my program.
Thanks.

Dennis_Knutson wrote:
As you can see from the specs, the digital lines are software timed. The ms rate you are getting is about the best you can hope for and with windows, that will be subject to considerable jitter.
The digital lines are software timed, true. But why do you think that 1 ms is the fastest that software timed IO can operate? Do you have any evidence or reference for this? In my opinion that statement is naive.
Open up your favorite programming environment and write a simple loop. Using .Net on a modern PC (e.g. 1.6 GHz+) you'll see that the loop runs MILLIONS of times per second. I benchmarked my fairly slow PC at 7 million loops per second. That is 7000 loops PER MILLISECOND! Now add in some function call that communciates with the hardware, for example AnalogMultiChannelReader.ReadSingleSample(). Even with this function call (accurately returning the correct voltage) the loop operates at 4MS/s -- i.e. 4000 samples per millisecond.
So is digital output limited by software execution speed? NO!
Is digital output limited by USB communication speed? NO!
The 1 ms limit for digital output is NOT some jittery approximate speed. It is a very precise, controlled timing. To see this, place a function call that performs digital output in your benchmark code, e.g. using the following function: DigitalSingleChannelWriter.WriteSingleSamplePort
If you benchmark a loop in which you use that function but write the SAME value to the port (e.g. 0) over and over, you will see that runs at about 100 kS/s (i.e. about 100 times per millisecond). I'm guessing this is because the NiDaqmx driver realizes that the output is already set to the specified value and does not lock the thread for the 1 ms timeslot.
However if you write alternate values to the port, such as:
while(time < 1000)
writer.WriteSingleSamplePort(false, 1);
writer.WriteSingleSamplePort(false, 0);
You will see that this operation executes at ~500 loops per second, which is exactly 1000 writes per second. Moreover, if you time each function call individually, you will see that they consume EXACTLY ONE millisecond each.
(Note that in your own testing, you may see anywhere from 490 to 500 loops per second, depending on processor load, but this is only because the thread manager could devote time slices to another thread during the benchmark. But if you are careful to measure only the time consumed by the digital output function calls, you will see that they are exactly 1 millsecond each).
So in summary, both software execution and USB communication occur at well over 1MS/s. Function calls to write the SAME digital output value to a port execute at about 100 kS/s, but writing alternate on/off values (to a single line or to a whole port, it doesn't matter) occurs at precisely 1 kS/s (i.e. 1 ms each).
So this 1 ms limit IS NOT an operating system or software execution timing issue. My guess is that it is imposed by the NIDAQmx driver, and may be specific to the device being used.
With a device that is hardware timed, you can certainly avoid this issue. But that in itself doesn't mean that software timed IO needs to be limited to 1 ms. (Indeed analog input can easily be performed at up to 48 kS/s).
Does anyone have a reference that explains the precise 1 ms delay when writing digital output? Does anyone have a reference regarding the maximum sampling frequency of digital IO on the USB-6008/9 ? (The sampling frequency for analog input is given in the specifications, but NOT the digital sampling frequency)
Thanks!

Itunes Running Slow

Hi All, I purchased the mac about a year ago for music (logic and itunes) as i loved itunes on the pc the more the music catalogue grew the slower itunes got. I purchased a mac mini and with a largish collection all was working fine. I then decided to rip some music videos, and noticed that around 15 seconds into the song the video would freeze I thought that maybe the mac mini was not up to the job with its 5200rpm drive so VLC most of the videos to watch. Itunes recently has also slowed down with spinning beach ball a lot of the time this is because I drastically increased the size of the audio catalogue to doube in size.
I have pinpointed the problem to the way itunes handles its cataogue. Everytime I get a freeze looking in the itunes folder where the xml and itl file is a temp file appears then dissapears. It seems its writing about 100MB each time this temp file appears, im guessing its updating the database with the playcounts etc. I moved these files to firewire external drive and it speeded things up a little however the problem still exists with a blip in playback on every video without fail.
Has anyone been able to fix this issue? I am guessing that a mac pro would be a solution as it would be able to handle the writing of the temp file at the same time as keeping OSX running and the video playing but would like to avoid this. Seems like bad programming to me? There should be more than 1 database?
Thanks
Shane.

To add - writing 100MB file to the itunes firewire drive while a video is playing does not cause the video to jitter!

CRIO9074 RT jitter every 10 sec. when writing data to SD card through 9802 module

Hi,
I am trying to use cRIO 9074 to collect data from different sensors at 50Hz and log the data to SD card plugged in 9802 module. I use FPGA- scan interface hybrid mode because some sensors are just based on analog signals and others(i.e.. IMUs) are based on RS232. This structure worked well. I used to transfer all the data to host VI in my desktop and log them there.
Recently, since I have more and more sensors, I decide to log all the data locally to SD card on cRIO 9074. However, I have a trouble.
I found my data are not continuous and always miss one second after ever other 10 seconds. So I tried to insert a FIFO to buffer the data between two timed loops. The high priority loop is in charge of collecting data and the low one is in charge of writing. But the problem still exists. Actually, the problem has nothing to do with FIFO because 50Hz is slow and I have validated that 9074 can collect and write all data within 10ms(100Hz). Even with out FIFO, the program should work.
Finally, I find out an phenomenon that both the two interaction variables "i" in the two timed loops will periodically stop for one second after every 10 second( I check them through front panel and probe). At the same time, the CPU usage increase dramatically and after one second, it will go back to normal level. That means the RT jitter every other 10 seconds and cannot work at this instant. If I fully delete the SD writing blocks, the problem is gone and the system works very smoothly. So most likely, the problem is due to SD card module.
I tried different ways, i,e, changing the loop priority, clock resources, the size of fifos. Nothing works. I even reduce the system frequency by two to 25 HZ, and even by 5 to 10 Hz. The problem still exists.
Attachments are two CPU usage check at 50HZ and 25HZ. Usually it is below 80% at 50HZ so that the capability of CRIO9074 is not a problem at all.
And I also attach my RT VI which is messy, because I almost go crazy thess days due to the problem . Does anybody have chance to check is there anything wrong in my VI? Or do I need to change the configuration of CRIO 9074 or update the RT engine? It seems like a hardware problem.
Does anybody face the same problem before?
Yizhai
Rugers Univesity

Hi,Zach-H,
     Thanks. Actually, my problem is already solved after I contacted one NI engineer online.
     I shouldn't use timed loop to write SD card.   Because SD card batch writing is time consuming and its priority can't be high. "while loop" is good for SD card writing.
   Yizhai

Shoot in high speed and slow down in FCP

Hi All
I’m planning to shoot footage HD that I would like to slow down almost 20% but I’ll rather avoid the jitter that usually shows on the video. I understood that I have to shoot in high speed. Do you have any suggestion of how to do this…
I was thinking to change the shutter speed of my camera but I’m not sure how much I have to change it.
I’m shooting with a Sony FX1
Best and thank you for the help
Lina

To shoot at a 'high speed', you need a camera such as the Varicam that will record at higher frame rate than 30fps. I believe the HVX-200 will allow you to overcrank things a bit (60p).
Otherwise, something like Shake will do a much better job slowing footage than FCP.
Good luck.

4G jitter and packet loss - Solutions?

Hi there I have recently purchased a 4G dongle as the ADSL into the house is woefully slow. My primary use is for gaming but I am finding that my online experience has been very underwhelming. Upon testing I found the service to have a jitter of 20-30ms and I suspect I am losing packets also. My question is- is there a solution for this? I have ordered a high gain signal booster (MIMO TS9 antenna), will this help?

Hey thanks for your reply Yeah im only getting 1 ro sometimes 2 bars reception so hopefully the antenna will beef things up but I think it is what it is perhaps.

Slow mo jitter

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