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So a couple of years ago I was reading about the ZLIB documentation on compression and how it works. It was an interesting blog post going into how it works, and what compression algorithms like zip really do. This is using the LZ77 and Huffman Tables. It was very education and I thought it might be fun to try to write some of it in G. The deflate function in ZLIB is very well understood from an external code call and so the only real ever so slight place that it made sense in my head was to use it on LabVIEW RT. The wonderful OpenG Zip package has support for Linux RT in version 4.2.0b1 as posted here. For now this is the version I will be sticking with because of the RT support. Still I went on my little journey trying to make my own in pure LabVIEW to see what I could do. My first attempt failed immensely and I did not have the knowledge, to understand what was wrong, or how to debug it. As a test of AI progression I decided to dig up this old code and start asking AI about what I could do to improve my code, and to finally have it working properly. Well over the holiday break Google Gemini delivered. It was very helpful for the first 90% or so. It was great having a dialog with back and forth asking about edge cases, and how things are handled. It gave examples and knew what the next steps were. Admittedly it is a somewhat academic problem, and so maybe that's why the AI did so well. And I did still reference some of the other content online. The last 10% were a bit of a pain. The AI hallucinated several times giving wrong information, or analyzed my byte streams incorrectly. But this did help me understand it even more since I had to debug it. So attached is my first go at it in 2022 Q3. It requires some packages from VIPM.IO. Image Manipulation, for making some debug tree drawings which is actually disabled at the moment. And the new version of my Array package 3.1.3.23. So how is performance? Well I only have the deflate function, and it only is on the dynamic table, which only gets called if there is some amount of data around 1K and larger. I tested it with random stuff with lots of repetition and my 700k string took about 100ms to process while the OpenG method took about 2ms. Compression was similar but OpenG was about 5% smaller too. It was a lot of fun, I learned a lot, and will probably apply things I learned, but realistically I will stick with the OpenG for real work. If there are improvements to make, the largest time sink is in detecting the patterns. It is a 32k sliding window and I'm unsure of what techniques can be used to make it faster. ZLIB G Compression.zip

Phew that is a pretty strong opinion! Although I personally am not a fan of the overall style of DQMH none of my problems are with the scripting/wizards or placeholder text. I think any framework that tries to do "a lot" will be complicated... your own personal framework (which you likely find trivial to use) is likely to be a bit weird to others. DQMH is extremely popular for a reason... To paraphrase the words of a wiser person than I, "please don't yuck someone elses yum"

Many years ago I made a demo for myself on how to drag and drop clones of a graph. I wanted to show a transparent picture of the new graph window as soon as the drag started, to give the user immediate feedback of what the drag does and the window to be placed exactly where it is wanted. I think I found inspiration for that on ni.com or here back then, but now I cannot find my old demo, nor the examples that inspired me back then. Now I have an application where I want to spawn trends of a tag if you drag the tag out of listbox and I had to remake the code...(see video below). At first I tried to use mouse events to position the window, but I was unable to get a smooth movement that way. I searched the web for similar solutions and found one that used the Input device API to read mouse positions to move a window without a title and that seemed to be much smoother. The first demo I made for myself is attached here (run the demo and drag from the list...). It lacks a way to cancel the drag though; Once you start the drag you have a clone no matter what. dragtrends.mp4 Has anyone else made a similar feature? Perhaps where cancelling is handled too, and/or with a more generic design / framework? Drag window out of listbox - Saved in LV2018.zip

Look at this new download on VIPM https://www.vipm.io/package/bjm_lib_request_power/

You want an ability to override the Equality or Comparison operators? I'm unsure, whether it really existed in OpenG packages, but now you have those neat malleable VIs, that let you do that: Search Unsorted 1D Array , Sort 1D Array , Search Sorted 1D Array. They have an additional input to specify your own equals or less function in a form of a custom comparison class or a VI refnum. There's an article to help: Creating a Custom Sorting Function in LabVIEW

This is exactly what was said in that ancient thread: Tree control in labview. So if you add 65536*N to the Item Symbols property of the Listbox and have the "Enable Indentation" option activated, you shift the symbol/glyph and the text N levels to the right. Could be useful for simple 'parent-child' relationships, if you don't want to use a Tree. And still it's used in Find Examples / NI Example Finder window:

I once went for an interview where they gave me a coding test and asked me to modify it. It was a very long time ago so I don't remember the exact modification they wanted (nothing to do with memory leaks) but I do remember the obtain queue and read queue inside a while loop with the release queue outside. I asked if they wanted me to also fix the memory leak as well as the modifications and they were a little puzzled until I explained what you have just said. I must have seen (and fixed) this while-loop bug-pattern a thousand times since then in various code bases. I also created this VI which I generally use instead of the primitives as it intialises on first call, can be called from anywhere, and prevents most foot-shooting by rolling them all into a single VI and ensuring all references but 1 are closed after use. Queue.vi

Those aren't typo's and errors. They are tests to see if we are paying attention.

In the past I have used the IMAQ drivers for getting the image, which on its own does not require any additional runtime license. It is one of those lesser known secrets that acquiring and saving the image is free, but any of the useful tools have a development, and deployment license associated with it. I've also had mild success with leveraging VLC. Here is the library I used in the past, and here is another one I haven't used but looks promising. With these you can have a live stream of a camera as long as VLC can talk to it, and then pretty easily save snapshots. EDIT: The NI software for getting images through IMAQ for free is called "NI Vision Common Resources". This LAVA thread is where I first learned about it.

Just to share how I got around this: By deleting 1 front panel item at a time I found that one single control was causing PaneRelief to crash; an XY graph. Setting it temporarily to not scale and replacing it with a standard XY graph (the one I had had some colours set to transparent etc) was enough to avoid having PaneRelief crash LabVIEW, but it would now just present a timeout error: I found a way arund this too though: the VI in question was member of a DQMH lvlib that probably added a lot of complexity for PaneRelief. With a copy saved as a non-member it worked: I could replace the graph, edit the splitters with PaneRelief without the timeout error (even setting the size to 0), then copy back the original graph replacing the temporary one, and finally move the copy back into the lvlib and swap it with the original. Voila! What a Relief... 😉 I probably have to repeat this whole ordeal if I ever need to readjust the splitters in that VI with PaneRelief though 😮

I confirm that this license is nearly identical to the standard EULA we use for our commercial products. Some wording is not applicable to a distributed palette of VIs like this. Our intention was to share a few reusable tools, used internally, with the community. Ideally, we should have released them under a standard open-source license such as MIT or a similar option. These VIs have been released “as-is,” without support or any guarantee that they will function for your specific use case. You may need to troubleshoot or fix any issues on your own. Feel free to use them in any context. I’ll look into whether it's possible to update the packages on the tool network to replace the current license with a more standard open-source one.

I put a temporary ban on inserting external links in posts (except from a safe list). We'll see what affect it has.

This is the modern 2020's equivalent of "works for me".

Your reporting of spam is helpful. And just like you are doing one report per user is enough since I ban the user and all their posts are deleted. If spam gets too frequent I notify Michael and he tweaks dials behind the scene to try to help. This might be by looking at and temporarily banning new accounts from IP blocks, countries, or banning key words in posts. He also will upgrade the forum's platform tools occasionally and it gets better at detecting and rejecting spam.

Apparently they moved it under Visible Items Edit: This also affects other types of structures.

Well, there are two aspects. The first is the technical one from hackers diving into the software and unhiding things that NI felt were not ready for prime time, to complicated for simple users, or possibly also to powerful. The main reason definitely always is however: if we release that, we have to spend a lot more effort to make it a finished feature (a feature for internal use where you can tell your users: "sorry that was not meant to be used in the way you just tried") is maybe 10 - 20% of development time than the finished feature for public use. There is also support required. That costs money in terms of substantial extra development, end user quality documentation (a simple notepad file doesn't cut it), maintenance and fixing things if something does not match the documented behaviour. And yes I'm aware they don't always fix bugs immediately (or ever) but the premise is, that releasing a feature causes a lot of additional costs and obligations, if you want to or not. The other aspect is, if someone who is an active partner and has active contacts with various people at NI, he is infinitely more likely to be able to influence decisions at NI than the greatest hacker doing his thing in his attic and never talking with anyone from NI. In that sense it is very likely that Jim having talked with a few people at NI has done a lot more to make NI release this feature eventually, than 20 hackers throwing every single "secret" about this feature on the street. In that sense the term "forcing NI's hands" is maybe a bit inaccurate. He didn't force them, but led them to see the light! Not out of pure selfless love, but to be able to officially use that feature for himself. The according Right-Click framework was a proof of concept to see how this feature can be used and mainly an example to other users how it can be used, and indeed once it worked it had fulfilled its purpose. That it was not maintained afterwards is not specifically JKI's fault. It is open source, so anyone could have picked up the baton, if they felt it was so valuable for them. The problem with many libraries is actually, if they are not open source and free, many complain about that, if it is open source and/or free, they still expect full support for it! In that sense I have seen a nice little remark recently:

Well, you are missing some important details in "The story of how this came about". So maybe indeed "it is worth a post of its own". It was LabVIEW 7.0 where they forgot to put a password on one of the VIs shipped with LabVIEW. And that VI had some node(s) on its block diagram including, I think, the BD reference property for the VI class. The community indeed got excited. But what did NI do? They tried to hide everything again in LabVIEW 7.1! I made a joke then that "our mother" NI must had had a PMS so she put the most interesting toys on a top shelf. So I made a"ladder" for us, kids, to get to them again and called it hviewlabs was me then, because that was a name of my company I used to sell my LabHSM Toolkit, an actor framework with actors controlled by hierarchical state machines (statecharts), long before the Statechart toolkit by NI, "THE Actor Framework", DQMH, and even before LVOOP. After PJM_Labview has published his private class generator http://forums.lavag.org/index.php?showtopic=307&hl=# and class hierarchies http://forums.lavag.org/index.php?showtopic=2161# and http://forums.lavag.org/index.php?showtopic=314&hl=hierarchy# (neither topic is available anymore) it became clear how to get access to private classes, properties and methods. However, it wasn't convenient enough. My PMS Assistant made it really easy. It gave back the access to those features to a much wider community of LabVIEW enthusiasts As you can see from the PMS topic discussion, by that time brian175 already had made his DataAct Class Browser. And he got really excited about the possibility not only browse but also to actually create objects, property and method nodes with the properties and method NI didn't want the users to see. By April of the same 2006 he figured out object creation too and incorporated the capabilities of PMS Assistant into DataAct Class Browser. At that point, I guess, NI decided that "the cat is out of the bag" and there is no point to resist. Nevertheless even after VI Scripting was made released by NI some classes, and even some properties and methods of public classes remain hidden even in LabVIEW 2024. I wonder why DataAct Class Browser is no longer available (as of January 2025) as well as original findings by PJM_Labview even here, on LavaG. Did NI "politely asked" admins to remove all that and just forgot about my PMS Assistant?

There is an example shipped with LabVIEW called "Image Compression with DCT". If one added the colour-space conversion, quantization and changed the order of encoding (entropy encoding) and Huffman RLE you'd have a JPG [En/De]coder. That'd work on all platforms Not volunteering; just saying

The thing I loved about the original LabVIEW was that it was not namespaced or partitioned. You could run an executable and share variables without having to use things like memory maps. I used to to have a toolbox of executables (DVM, Power Supplies, oscilloscopes, logging etc. ) and each test system was just launching the appropriate executable[s] at the appropriate times. It was like OOP composition for an entire test system but with executable modules. Additionally, crashes were unheard of. In the 1990's I think I had 1 insane object in 18 months and didn't know what a GPF fault was until I started looking at other languages. We could run out of memory if we weren't careful though (remember the Bulldozer?). Progress!

Hello ladies and gentlemen! Prepare yourselves for a massive wall of text. Thank you in advance. First time poster, long time lurker. Over the last decade I have found answers to a myriad of Labview related questions I've had on these forums, and I'm hoping some of you can help me out with my current conundrum. I've a solo developer for a large labview based automation project. I have worked with other labview developers in the past, but we've always kept what we were working on very compartmentalized because nobody ever wanted to deal with LVMerge. At the time they all said Labview effectively had zero way to merge VIs. Since those old days (9 years ago) we've come a long way. Unfortunately like many engineers I am horrible about UI/UX design - I'm trying to fix basic functionality, I don't care that you can't find the button (at least I don't care right then). But because of how solid the software is getting we're finally in a good position to start dedicating time and effort into improving our UI flow and design. So in the run up to this, and knowing I had basically zero experience with LVMerge/Compare except that the previous developers considered it "impossible", I did a few tests. My goal was to continue some development in the block diagram of the main top level VI in my own git branch, while another developer worked on UX changes on a second git branch. Then when he was ready we'd merge everything back together. All of his changes were focused on the Front Panel - he never opened the block diagram once. He was moving things, resizing things, changing captions and boolean texts, but never labels, and then adding various decorations as he wanted for clarity and organization. My initial test merges worked flawlessly. I was surprised how easy my small merges worked. From there he tinkered away when he could over 4ish weeks on the UI and I kept my usual pace on the main top level working on various bugs. I tried to limit what I was doing in the top level - most of the block diagram changes I made were cosmetic. It needed some TLC. Anyway fast forward and now we're ready to merge everything back together and ... I can't. I cannot get it to work. I've tried so much stuff. At first the errors were almost always during the LVCompare phase, usually about an insane block diagram object on the "base" vi. I'm familiar with heap peak so after a crash I'd comb the error log as well as I could (wish that thing had some documentation) and then try to find the offending object and fix it. More often then not I wouldn't see an issue with the object at all, and lots of the advice online is "just delete and remake the object" but I hate that solution because it means I fundamentally don't understand the actual problem, and when I'm merging three different versions of a big VI that gets tough to do. I've been experimenting with the tools, and eventually turned off auto resolve. Okay cool that would get me through the compare stage and actually open LVMerge where I could select which versions of things I wanted. From here it became a game of cat and mouse where I go through changes one by one till I get a crash, investigate, fix, change something related to said crash, and then run it again. This has been time (and sanity) consuming. It never worked, and eventually I got stuck on a merge change that I couldn't even identify what it was changing between the three, but I know that no matter which I select it crashes. I've kept trying various things since then. Resizing the tab control positions to be exactly the same Deleting a few FP objects on the base and FP update versions that I had removed when making BP changes on my version Adding a few objects I created for the same reason Added all 3 versions of the VI to the main most up to date project, opening and running them all to make sure there are no serious insane objects that are breaking them. They all run. This is by no means an exhaustive list of everything I've tried, but its what comes to mind right now as the major tries. Currently the state I'm in is that when I run it with all 3 versions with all the changes from above made to them, I can't get through the Compare stage because it crashes with a insane object error about "undo.cpp" which makes zero sense to me. What is it undoing? I tried limiting the number of Undos in LV settings, that didnt help, I tried increasing the limit greatly, that also didn't work (maybe didn't increase enough? Trying that now). I'm really deep in the weeds on this one now, and I would love some fresh perspectives. What's probably going to happen is that I'm going to write it all off as a lesson, and we'll just have the UI dev make his changes again on my current most up to date version - but I would really love to figure out the compare and merge process, and best practices for using it. The documentation for these is abysmal. There's basically nothing. I could probably pay for NI's annual subscription and maybe get some direct help from them but I had it out pretty big with some NI sales guys a few years ago when they transitioned away from perpetual licenses to the subscription model, and I don't want to pay them on principle; but I will if needed. Ultimately even if we do the changes again, I'd still like some best practices on where we went wrong and how to avoid this in the future. We're growing fast, and I could see having another full time labview developer working with me in the future and would love to come away from this with as many answers as possible on how to work in a team on labview binary files. If you've made it this far all I can say is thank you. Now please send help. PS: some info I should of added we use Labview 2021. I don't think we're on SP1, I don't remember why not, and I am willing to try updating. also willing to pay the sub and just upgrade to 2025, but not without good reason like someone tells me all about how they solved so many issues with Compare/Merge in the last 4 years and its going to be so much better I'm attaching my most recent error log from the crash I had last night. Its a doozy, reporting a TON of objects on both the FP and BP as insane. lvlog2025-08-11-15-32-09.txt

My problem was on a windows machine but I managed to solve it; I found that using LVCompare also segfaulted on the same file, but did not segfault with the -nofp command line option. With this I was able to confirm the specific file that both LVMerge and LVCompare were segfaulting on, and systematically delete half the code and re-test whether LVCompare would crash. After a few hours I was able to track down the offending piece of code to a random chart; I'm honestly still not sure what was causing them to segfault, but deleting and replacing the chart fixed the issue. Hope this helps someone else out there!

This toolkit offer you an efficient, stable, and reliable front panel control value refresh function. User can design their UI dashboard without any code development. 1. Powerful parallel execution capability, Support clone reentrant execution running mode, you can create multi dashboard UIs at the same time and controls can synchronous refresh across different UI. 2. High-speed data refresh capability, even with thousands of controls on a single UI, can easily maintain a refresh rate of 50ms while consuming very little CPU resources. 3. Support all control data types that "Tag Engine" support, this mean the only thing you need to do is to change the control "Label" with "Tag name", then the control will refresh automatically. 4. Support "muParser Expression", you can type the control "Label" with "Expression" that muParser Expression support, For example "a + b" "a > 1 & b >= 2".

QUIC

Hi My advice for managing multiple versions of LabVIEW is always the same : >>> Install only one LabVIEW version per partition if you also need to install any driver, toolkit or module. Or need other software that integrates with LabVIEW in some way. No exceptions. I do have VMWare installed with Windows XP to be able to open ancient LabVIEW versions like 6.1 or read the old CHM help files, accepting the sluggish performance of the VM environment. I avoid using it for anything 'serious'. To manage the span between LabVIEW 2018 and 2024 I would divide the disk into two partitions and install two copies of Windows and then install LabVIEW. To manage multiple partitions and selecting which to boot from by default, I recommend installing EasyBCD. But you don't have to. Windows creates a simple multiboot menu itself. There are other options too. But they require some dedication going into the art of multiboot management. ¤ You can install Windows on an external USB3 connected disk, SSD or FlashDisk. Microsoft abandoned the concept in 2020. But a program called Rufus revived the concept and now there are many tools that gives this as an opportunity. Works splendidly even with Windows 11. ¤ Some laptops ( and desktops of course ) support easy change of the disk. Sometimes using a replaceable disk craddle instead of the DVD drive. Good luck

I think this is fixed now. Please check.

Yup. There is: MMAP (1.0.1).

Aren't DVR's just LabVIEW's take on pointers?

I cannot look at your file, but I suggest save the data to TDMS or any binary format of your choice. Once the file is saved, then you can convert it to text.

Hello everyone, I developed an Addons-Toolkit of LabVIEW, which achieves most of the OpenCV's APIs. It includes more than 2700 VIs, covering 13/15 modules of OpenCV (except flann and gapi) . You can use it to control cameras, process images, run DNN models and so on. Welcome to my CSDN blog to download and give it a try! (Chargeable, 30 days trial) Requirements: Windows 10 or 11, LabVIEW>=2018, 32 or 64 bits.

Had the same issue. Removing a VI from a lvlib, using Pane Relief to set splitter size and moving it back to the the lvlib worked for me to. Thanks!

yeah that is the payload 😉

That's how I'd do it. Then combine that with the Foreign Key Sort from my Array package, putting the Time Stamps into the Keys, then paths into the Arrays, and it will sort the paths from oldest to newest. Reverse the array and index at 0, or use Delete From Array to get the last element, which would be the newest file.

I can create it without problems in LabVIEW 2018 and 2020! So it is either that Scripting is not enabled in that LabVIEW installation or a bug in backsaving some of the scripting nodes to earlier LabVIEW versions. And I'm pretty sure that the Diagram property (called Block Diagram in the menu) is available since at least 2009 or thereabout. I can check this evening. My computer at work only has LabVIEW versions back to 2018 installed.

Top Level here almost certainly doesn't mean the diagram of the template VI. Instead LabVIEW distinguishes between a Top Level diagram which is basically the entire diagram window of a VI and sub diagrams such as each individual frame inside a case structure but also the diagram space inside a loop structure for instance. The tricky part may be that the diagram itself may indeed only exist once and remains the same even for clone VIs. The actual relevant part is the data space which is separate for each active clone (when you have shared clones) and unique for each clone (when you have pre-allocated clones).

@Natiq this (non-functional example) should be enough to get you started. The weird arrow thing on the boundaries of the while loop is a shift register. The event structure can also be configured to have a timeout case where you can then perform other stuff, like reading your image and writing it to the reference on the the shift register. There is heaps of information out there (YouTube for example), a bit of searching will lead to some more details.

A bit sad to have to say this nowadays that most of the traffic on this forum is about leaked videos, money rituals and human sacrifices, but isn't this the part where someone starts to repost links to basic LabVIEW training resources on the NI site?

Indeed. It's not a full solution as it doesn't support multiple streams, audio or other encoding types. But if you want to get the audio then you need to add the decoding case (parse is the nomenclature used here) for the audio packets in the read payload case structure.

IIRC there are a couple of RTSP libs for around (a while ago now). Some are based on using the VLC DLL's and I even saw one that was pure LabVIEW. Might be worth having a look at them for "inspiration".

Makes sense. It just goes to show how ingrained workflows are and little things can trip you up. I was right-clicking over the N, over the I. Right clicking 2 pixels down/up from the edge. Top edge, bottom edge, left right.

Setting up the project:

i can't really answer your question but I suggest you watch this presentation :

There are several alternatives for the NI GPU Toolkit that are considerably more up to date and actually still maintained. https://www.ngene.co/gpu-toolkit-for-labview https://www.g2cpu.com/

I used LabVIEW to develop a toolkit for ATE software. The toolkit is called "Test bench Framework", which includes a test sequence editor and a test engine.This toolkit features the ability to execute several different sequences in parallel.If you are interested in this kit please contact me, thank you! This toolkit is over 10MB in file size and cannot be published on VIPM, so I uploaded it to Github.Test-Bench-Framework . I used the TestStand icon inside my own sequence editor and wondered if there would be any copyright issues involved.But it's not commercially available yet.

Here is a VI that gets the title of the window that is active. You could then continually loop until the title you expect is active, then perform operations. https://forums.ni.com/t5/LabVIEW/Get-Current-Active-Window/m-p/3930389#M1116926

I don't have good examples to share, but here are a few helpful links for you: NI has an article dedicated to DVRs, which also explains the fundamental idea: http://www.ni.com/product-documentation/9386/en/ Here is a short video that explains how to use a DVR and some of the pitfalls: https://www.youtube.com/watch?v=VIWzjnkqz1Q Of course, you'll find lots of topics related to DVRs on this forum.

Here is a quick and dirty edit. It allows for column separators to be moved, but I noticed that on resize it will set the column widths. So this means if you manually move the columns, and then resize the control it may change the columns in an unexpected way. But at that point you can manually move the separators again. I only have 2017 and 2018 so this is for 2017 and newer now. Variant_Probe-2.4.3-0.ogp

Looks like someone beat me to it! Oh well, I already exported it (also for 2009, incidentally) so I'll post it here in case it'd be more convenient to use a regular VI file. 0 to -4096.vi

Updated VIs to obtain hwnd by FP.NativeWindow as suggested above. Saved in LV 2013 SP1. Only tested with Windows 7 64-bit and LV2013 SP1 32-bit. Set Calling VI Wnd Top & Active.vi Set Calling VI Wnd Topmost & Active.vi Cancel Calling VI Wnd Topmost.vi

These are two separate issues: drag over not working, and drop deleting tree items. You can use the attached VI to copy a tree and event structure out of. What's important is that you have the old event ("Drop?", not "Drop"). You can replace the tree with a system tree as long as you right click on the tree and select Replace. Don't delete the tree. TreeWithDropEvent.vi

The OpenG Pipe Project does just that. It is a LabVIEW Library that replaces the System Exec function and returns pipe refnums for the three standard IO interfaces and functions to read and write to those refnums. The project hasn't been released yet as I consider it not entirely release quality but it does work for me and I have actually used in in several of my projects already. Since there is no officially released package yet you can't just download it through VIPM from internet. But here is a copy of a package you can install using VIPM. oglib_pipe-1.0-1.ogp