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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"

Seems like this one has "escaped everyone's grasp" too. ParallelLoop.ShowAllSchedules=True Because was only checked from the password-protected diagram of ParallelForLoopDialog.vi (LabVIEW 20xx\resource\dialog). Present since LabVIEW 2010. When activated, allows to apply more advanced iteration partitioning schedule. In other words, instead of this you will get this Сould this be useful? I can't say. Maybe in some very specific use-cases. In my quick tests I didn't manage to get increase in any productivity. It's easy to mess up with those options and make things worse, than by default. Also can be changed by this scripting counterpart.

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.

For fun. 😄 "Science isn't about why; it's about why not!" - Cave Johnson

Found it here @Ajayvignesh https://github.com/sandialabs/LVTM

A Timestamp is a 128 bit fixed point number. It consists of a 64-bit signed integer representing the seconds since January 1, 1904 GMT and a 64-bit unsigned integer representing the fractional seconds. As such it has a range of something like +- 3*10^11 years relative to 1904. That's about +-300 billion years, about 20 times the lifetime of our universe and long after our universe will have either died or collapsed. And the resolution is about 1/2*10^19 seconds, that's a fraction of an attosecond. However LabVIEW only uses the most significant 32-bit of the fractional part so it is "only" able to have a theoretical resolution of some 1/2*10^10 seconds or 200 picoseconds. Practically the Windows clock has a theoretical resolution of 100ns. That doesn't mean that you can get incremental values that increase with 100ns however. It's how the timebase is calculated but there can be bigger increments than 100ns between two subsequent readings (and no increment). A double floating point number has an exponent of 11 bits and 52 fractional bits. This means it can represent about 2^53 seconds or some 285 million years before its resolution gets higher than one second. Scale down accordingly to 285 000 years for 1 ms resolution and still 285 years for 1us resolution.

With ZLib you just deflateInit, then call deflate over and over feeding in chunks and then call deflateEnd when you are finished. The size of the chunks you feed in is pretty much up to you. There is also a compress function (and the decompress) that does it all in one-shot that you could feed each frame to. If by fixed/dynamic you are referring to the Huffman table then there are certain "strategies" you can use (DEFAULT_STRATEGY, FILTERED, HUFFMAN_ONLY, RLE, FIXED). The FIXED uses a uses a predefined Huffman code table.

😅 You might be waiting a while, I'm mostly interested in compression, not decompression. That being said in the post I made, there is a VI called Process Huffman Tree and Process Data - Inflate Test under the Sandbox folder. I found it on the NI forums at some point and thought it was neat but I wasn't ready to use it yet. It isn't complete obviously but does the walking through of bits of the tree, to bytes. EDIT: Here is the post on NI's forums I found it on.

From what I can remember, for LV 5.0.x and older RTE (i.e., a loader plus small subset of resources) was included into the EXE automatically during the build process. For LV 5.1.x there was a choice: to include RTE into the build or to use an external RTE. And since LV 6.0 only an external RTE was supposed. I could say more, such a trick is still possible for all modern versions on all three platforms (Win, Mac, Linux). The latest version I tested it on, was LV 2018, but I'm pretty sure, the technique hasn't changed much. I can't remember, from which version NI started to use Visual Studio 2015, but since then each EXE requires The Universal CRT, that is contained in Microsoft Visual C++ 2015 Redistributable. One could install such a distro on a clean machine or copy all these files from the machine, where such a CRT is already installed. Now besides of those the application will also require this minimal subset of folders/files (true for LV 2018 64-bit): On Linux it goes much easier (true for LV 2014 64-bit): For LV 2018 64-bit with a "dark" RTE it also wants And for Mac OS you can embed RTE into the application with this script: Standalone LabVIEW-built Mac Application with Post-Build Action. Of course (and I'm sure everyone understands that), the technique described above, is applicable to very simple 'a la calculator' apps and not very to not at all for more or less complex projects. The more functions are called, the more dependencies you get. If something from MKL is used, you need lvanlys.dll and LV##0000_BLASLAPACK.dll, if VISA is used, you need visa32.dll, NiViAsrl.dll and maybe others, and so on and so forth.

I don't do Discord. I don't even do Ni.com. Feedback isn't really necessary. I only knocked it up because I went down a rabbit hole and wasn't impressed with the existing LabVIEW solutions. I thought I'd throw it in here to see if someone could improve it. My solution is optimised but there may have been a better alternative solution or maybe someone had a nice JPEG one (LSB doesn't survive JPEG compression). You might get a mention in the readme just for responding

Thanks, I'll be honest, I'm allergic to Discord. Vehemently so. To the point where I refuse to use it. Just seems like a lot of unfiltered noise to this old man. I'm gonna play with NodeRed and see if it's the tool of choice. And oh, back in the day I was a National Instruments Alliance Member. Dunno if that's still a thing or not. Cheers,

You may also want tell people where you can actually download or at least buy this. Although if you want to sell it, do not expect to many reactions. It is already hard to get people to use such toolkits when you offer them for free download.

I would suggest rabbitmq, i want(ed) to present it at a LabVIEW user group (LUGE) but haven't done it yet. It's very powerful. I use redis and did a quick presentation (in french) at LUGE recently, i haven't used the stream feature though, I only used it as cache.

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 posted a demo set of VIs here which can pop up a window, centered on whatever monitor the mouse is on. There's also settings to have the window center on the mouse wherever it is, but saying on the same monitor. And yes this uses the All Screens, Working Area properties.

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.

Drat, and now my typos and errors are put in stone for eternity (well at least until LavaG is eventually shutdown when the last person on earth turns off the light) 😁

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!

In addition to the LV native method, there are options with .NET and command prompt: Get Recently Modified Files.

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.

Open the search function (Ctrl+F) and browse for the "NaN" constant. A dialog pops up telling you this palette item is not supported by the Find Dialog... You can search for the "NaN" string and it will find all the NaN constants (plus all the occurrences of the "NaN" string). You can search for all other constants (pi, machine epsilon, +/-Inf, etc.), but not for the NaN constant, which is just a numeric constant with NaN typed in it. You can search for ALL numeric constants, but not for a specific one, say "1". Of course, you can search for all "1" strings in your code, and the constant 1 will show up among the search results, but it will be hidden in a long list of irrelevant results. And try to search for a constant with units... You can't. What would be nice is to look for a constant irrespective of its unit, as for instance 60 s = 1 min. Did I encode that time constant as 60 s or 1 min? I need to search for 60 AND 1 to find out.

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.

Since you asked, here are my findings: LV23 - can create the attached snippet (don't know if it works), and save it for LV14 (also attached). All the pulldown menues show relevant properties LV21 and LV 19 - open the saved for LV14, show a correct image, but the first property node lacks the "Block Diagram" entry in the pulldown; further properties have no menu ETA - and show the relevant pulldown menues when "Show VI scripting" is checked. LV14 - the first property node menu *has* a "Block Diagram" entry, but the further properties don't match LV23 W14.vi W23.vi

Example of camera grab using the Pylon .net API. (Credits: GrokAI)

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.

If you look at the actual array sizes, things will make a lot more sense. 1. The Build Array will add the number of expanded elements to the first dimension. The array size after the first Build Array is (2,0), which is still an empty array. 2. The Transpose Array will swap the array sizes. The array size after the Transpose Array is (0,2), which is still an empty array. 3. Again, the Build Array will add the number of expanded elements to the first dimension. In this case, it will add 1 to the first dimension, resulting in the array size being (1,2), which is no longer an empty array.

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".

What doesn't work with the function: AJ_NETSDK_IPC_PTZControl() on page 21/22? Or are you not using the SDK functions to retrieve the RTSP stream but some other ready made interface for LabVIEW? Meaning you have no idea how to interface to a DLL? A few points to consider: 1) The camera may not like a secondary connection, either through the SDK or through generic TCP/IP while it is busy streaming image data to the VLC or whatever interface. 2) Trying to reverse engineer the TCP/IP binary stream protocol is likely going to be cumbersome and difficult to realize as it is usually proprietary. The SDK interface is simple enough to use, except if you lack any and all understanding about C programming. It's not a CIN node either that you will need to configure but a CLN (Call Library Node). CINs are not only legacy technology but on most modern LabVIEW versions simply not supported anymore. An interesting problem, but none I can help you as I do not have that hardware, and I would expect it to be a bit cumbersome considering above 2 points.

Probably not the feedback you are expecting but we really should do something about the nasty root loop API calls in the input API. I have somewhat progressed with this over the years and have the windows stuff all working for mouse and keyboard (and a little of the Linux) but I don't have a Mac so can't do anything on that. If there is some interest then let me know and I will see if I can allocate time to getting an API together.

There is a "best practices" document (this too) but I suspect you are looking for a less abstract set of guidelines.

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

Well that's okay I felt like doing some improvements on the image manipulation code. Attached is an improved version that supports ico and tif files and allows to select an image from within the file. For ico files it basically grabs the one image you select (with Image Index) and make an array of bytes that is a ico file with only that image in it, and then displays it in the picture box. For Tif files there is a .Net method for selecting the image which for some reason doesn't work on ico files. Edit: Updated to work with Tifs as well. Image Manipulation With Ico and Tif.zip

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

Sweet! That solves it. So, now we can write a LabVIEW console app! Here is the VI that let's you write to the StdOut of the calling console: Write to StdOut of Calling Parent.vi -John

It adds properties and methods to the LabVIEW VI server hierarchy, mostly application related and presumably project and other such stuff, that NI considers to dangerous, untested, or giving to deep insight into LabVIEW. It is related to scripting but not the same thing. Rolf Kalbermatter

Maybe you'll get Xmas before you know it... I found a way to retrieve all tags from a VI. I basically scan the VI file and get an index to the position of tags in the file. I then extract the tag names. Since I don't know to which objects it is related, I have to scan all objects on FP and BD to associate them properly. Once done, you get a list of refnums and variants for the Object's references and a list of tags to which it is associated. I also included an example of code to write a tag to the Block Diagram. Use the same template to write to FP or any objects. Open the project and launch "Get All Tags from VI". Browse the path to the example file "Tagged Test VI" and that's it. Saved in 8.6 but will work in 9.0 (2009) as well. Note that the versioning is important as tags are seen only through scripting and NI can change the way it is saved from one version to the other. Retrieve Tags 8.6.zip