Two Threshold Analog to Digital

I was asked to develop some code that would take a signal in on an analog, then convert it to a digital, then perform frequency, duty cycle, and signal integrity testing on it. The built in NI functions for performing these tasks were insufficient because we needed to be able to detect a single drop out of a cycle. With a real world signal I realize there maybe noise and a having a single threshold to convert from a analog to a digital may show transitions that aren't there and so I planned on developing some kind of debounce code.
Instead someone mentioned using two thresholds, one for the low and one for the high, and to only consider the signal transitioning if it goes above the high, after going below the low.
Attached is my attempt at that method. This VI simulates a sine wave with a bunch of noise then does a single theshold to show how imperfect it can be. Then using that same signal it does a two level theshold which works much better but has a slight shift in the time domain, and the beginning will contain unknown values because neither transition has occured with the first sample.
Any pointers or suggestions to improve my implementation is appreciated. Thanks.
EDIT: This does use an OpenG function from the Array palette.
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Solved!
Go to Solution.
Attachments:
Test AI to Digital With 2 Levels.vi ‏72 KB

Why so many loops when you just need one?
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I made an account and am replying to this because i have the exact same computer as you and i was also at best buy at around 3pm wondering the exact same things you were! The DVI port on our MacBooks are different than the standard DVI ports. Freaking weiiiiiiiiiiiiiird! Get out of my head!!!!
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Hi again ftts (having a little trouble pronouncing that)
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http://esupport.sony.com/US/perl/model-documents.pl?mdl=DCRTRV22
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Analog to Digital (ie VHS to DVD)

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B's Fan

Just a question.....if you have all these old VHS home movies, don't you already have a VCR? What have you been playing them on all these years?
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Simultaneous analog and digital waveform read with PXIe-6361 and BNC2120 ?

Hi there,
I am trying to collect both analog and digital signals from a PXIe-6361 linked to a BNC2120, using the attached VI. I am running Labview 2011 64bit. This is the first time I am working with digital input. On the 2120 board, I have the digital input BNC cable connected to User Input 1 and wire between the screw terminal of UserInput 1 and the P0.1 (Digtial I/O) screw terminal.
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Error -89137 occurred at DAQmx Start Task.vi:3
Possible reason(s): Specified route cannot be satisfied, because it requires resources that are currently in use by another route.
Property: RefClk.Src
Source Device: PXI1Slot2
Source Terminal: PXIe_Clk100
Required Resources in Use by
Task Name: _unnamedTask<6>
Source Device: PXI1Slot2
Source Terminal: None
Destination Device: PXI1Slot2
Destination Terminal: RefClockInternal
Can anyone point me in the right direction for troubleshooting this?
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Thanks for your help,
Claire.
Attachments:
Export Waveforms To Spreadsheet File (1D)_wo extra line.vi ‏33 KB
Multi-Device Synch-Analog Input-Finite Acq-Analog Start_Claire_wDigitalin.vi ‏105 KB

Hi ClaireJ,
Sounds like a reference clock conflict. This KnowledgeBase (KB) talks about this error when using simultaneous sampling. Also, might want to check the device routes in Measurement and Automation Explorer (MAX) as discussed here. Finally, if you are routing your PFI line over a RTSI connection, this error can occur. This KB discusses it.
As to your second question, this post should help.
Bill E. | Applications Engineer | National Instruments

How to capture using Pinnacle 700-USB Analog to Digital (USB)?

I have a Pinnacle 700-USB Analog to Digital converter which inputs Composite and L+R Audio and outputs a Digital signal through USB.
I'm using this to digitize VHS tapes.
I am trying out different Video Editing sw including Adobe Elements 7. Others like Pinnacle Studio 12 and Corel Video Studio 12 can import from this USB-device. It doesn't seem to be possible using Adobe Elements 7.
I've looked at the page http://help.adobe.com/en_US/PremiereElements/7.0/WS51F6C811-8B79-4c26-B4B9-24C0919182B6.ht ml
It mentions at the end "Note: If you capture using an AV DV converter, you might need to capture without using device control."
1) What does the last Note mean? Which device control?
2) Are there any possibility of this working? What should I try to play with?

My Pinnacle Dv500 came bundled with Premiere 6.0 which I updated to 6.02... and I also updated the Dv500 driver software from the V3 to V4.5a so it would save in "standard" DV AVI Type 2 48khz files, instead of the ones that required the Dv500 codec to edit
When I bought a new computer and started using WinXp instead of the Win2000 that came with my Alienware Pentium3, I could never get Premiere 6 to work... would start, flash a screen or two, and then just go away
I then bought Scenalyzer, since it was compatible with the Dv500 (still had to have P6 and Dv500 drivers installed) but it turned out to be very FRAGILE as any slightest glitch on the tape would stop the program... and since some of what I'm doing is capturing my OLD library of VHS tapes, that simply wouldn't do
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Just a "bit" of a hassle to have to restart between capture & edit/dvd... but much better than Scenalyzer stopping every time an old movie hit a rough spot in the tape... rough spots that capture just fine with P6

Producer consumer with analog and digital inputs and outputs

Hi everyone,
I am working on a control system program for some practical test work. Currently I am working on the data acuisition component of the Labview program. My architecture is produced-consumer loops with a que. My system will have analog inputs, analog outputs, digital inputs and digital outputs. It's not a time critical sytem, but I would like all of the data acquisition to be synchronised. I have attached my program as it is at the moment. I am having trouble getting all of the data into the que since I have two data types. Also, I'm not sure if i've synchronised the four read/write sequences correctly. I would greatly appreciate if somebody could take a look at my program and give me some advice. Thanks in advance.
Solved!
Go to Solution.
Attachments:
control_v2_DAQ loop.vi ‏46 KB

Robert, the specific error that I get is:
Error -200462 occurred at DAQmx Start Task.vi:6
Possible reason(s):
Generation cannot be started because the output buffer is empty.
Write data before starting a buffered generation. The following actions can empty the buffer: changing the size of the buffer, unreserving a task, setting the Regeneration Mode property, changing the Sample Mode, or configuring retriggering.
Task Name: Heater testing lab digital outputs
This error occurs at the 'DAQmx write.vi' function. I just want to sent one sample per second, for each channel. I would like the producer and consumer loops to each run once every second.
I have attached part of my code with just the data acquisition and writing. Any help would be greatly appreciated.
Attachments:
control_v2_ML_simple.vi ‏83 KB

Archiving analog video digitally for later editing

Hi:
I'm a newbie to iMovie and have been through the discussion threads without finding an answer. Thanks in advance for any help.
I have about 16 hours of analog tape from a Hi 8 Sony camcorder. I just picked up a Canon ZR200 which allows me to use the analog to digital passthrough feature to move the old analog tape to the computer. I've been able to import some video and have some rather huge files. I see in the forums that an hour of DV video is about 13 GB which is consistent with what I have on my computer.
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In reading your response and other threads, I am
assuming that when I Share to a Full Quality movie, I
am making a quicktime movie as the output which will
be much smaller than the DV file; is this correct?
The Shared movie is smaller because it is shorter. But in terms of quality, the Full Quality export is exactly the same content as the DV video used in the iMovie HD project.
In iMovie HD, a "Full Quality" export creates a movie that matches the natural video of the currently active iMovie project. The video format varies by project type. A DV project exports to a different movie format than an HDV 720p project, for example.
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With no discernible loss in quality?
That's correct. There will be no loss of quality.
Thanks again for your help, Karl.
You're welcome.

No Analog to Digital Conversion Imports, eh?

Been messing around with FCPX using previously imported FCE files. FCPS doesn't care that they are VHS footage imported to FCE using my DV camera as an Analog-to-Digital Converter. It results in DV camera footage iimported as FCE .mov files, with which FCPX is quite happy.
This worked great until I decided to try the same procedure with the "new, improved" FCPX.
FCPX recognized the DV camera, displayed the video coming thru the camera from the VHS player, and had no objection when I pressed the import button. However, tuff cookies on actually importing anything. It created an Event, but placed no files in it.
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Well, I suspected as much, but how ya gonna know for sure if you don't ask?
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Never even looked at QTPro for capturing. Thanks.
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May not work for "power users" and their HD formats, but for working with DVDs as the target output its worth checking out.
As Macked said in his related thread (that I missed when I searched), its just plain stupid to have to use two (actually 3) programs for these simple tasks.
Thanks again.
Message was edited by: Clyde Crocker

Audio problems with Canopus analog to digital converter

I'm trying to digitize and import VHS tapes into iMovie 08. I'm using the Canopus 110 analog to digital device. I've connected the VHS player to the Canopus with RCA cables, as prescribed. The video has imported beautifully — but there's no sound, and so my then 2 year old daughter appears to sing, but alas, no voice — except, for the occasional clip (about 2 to 4 seconds of sound on a 30 minute tape). Any ideas? (I've spoken with an Apple tech who walked me through a test before assuring me the problem didn't seem to be with iMovie ['-).

Hi
a. You did install the Canopus programs (on CD) ?
b. I connect mine to a Standard VHS-VCR and use the SCART connector on it's back
and to this a RCA to SCART plug WITH AN IN AND OUT Switch !
On my VHS-VCR there are two SCARTs on it's back - only one of them works for this.
c. If You in iMovie pref - set Playback via Camera - picture will play but sound
will be directed to analog device = Your Canopus
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How to store the output of a analog to digital converter into an 2D array

Hi
I am doing my M.Tech Thesis in Image reconstruction and I am using labview for simulation and I want to know how to store the output of a analog to digital converter into an 2D labview array.

nitinkajay wrote:
I want to know how to store the output of a analog to digital converter into an 2D labview array.
How exactly are you performing 'Analog to Digital'???
Grabbing image using camera OR performing data acquisition using DAQ card OR some other way????
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How can I open two screens of Adobe digital editions at the same time?

How can I open two screens of Adobe digital editions at the same time?

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Analog to digital protocol

Hi again,
I got a lot of help yesterday on hardware devices that allow capture of analog video. Thanks.
That got me to wondrin... If I'm going to try to do this, I might as well learn the basics.
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Hi
Just some thoughts.
In my mind the videoconverter converts an analog video + audio signal
to streamind DV (digital format) that can be read by the FireWire port that
only accepts digital info.
So at least there is an analog to digital converting chip inside and in more
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Yours Bengt W

Two Threshold Analog to Digital

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