I need to create an ASN.1 BER encoded file with multiple records. I've been searching for one (tools like oss, asn1c, ... etc), but I can't find one that suits me with a full example on how multiple records can be encoded in one file.
Does anyone know a good tool?
Thanks
The tools won't really help you design your file-format, or protocol; that is a manual task that you must perform. You will need to design the rules of how data is stored and in what form each element will take.
The tools will help with implementation, allowing you to take your protocol definition and generating C or C++ code that is capable of decoding and encoding files that conform to that protocol.
The company I work for uses OSS Nokalva, which is the best, but expensive. I have also used asn1c, for personal projects, with success.
You can use asn1c and define multiple records with
MultipleRecords :: SEQUENCE OF SingleRecord
Related
"In traditional file processing, the structure of data files is embedded in the application programs, so any changes to the structure of a file may require changing all programs that access that file. By contrast, DBMS access programs do not require such changes in most cases. The structure of data files is stored in the DBMS catalog separately from the access programs. We call this property program-data independence."
The following text is taken from the book Fundamentals of the Database system. I didn't get the part about the traditional file processing can somebody please explain(an example would be appreciated)?
I'll give you a simple example.
Microsoft Excel used to save its files in a proprietary binary format. In practical terms, this meant that you could only work on those files using Excel.
But now, Excel supports an open document format in XML that is text-based, and allows other programs like the OpenOffice SDK to interact with them. So you no longer need to rely on Excel to work with open document format Excel files.
I've done a bit of research, and it seems that the file type .rsc is used is many different applications. I haven't been able to find any sort of resource extractor or decompiler that can deal with .rsc files.
The objects of my interest: Sounds, images, and other various resources compiled as .rsc files for an old (1999) game made by The Learning Company. Since I have found ways to do this for many other games, I assume that there must be a way to extract and view the resources in their de-obfuscated form.
If nobody has ever figured this out yet, I'm willing to learn about how to write a decompiler and interpret the files. I of course, would need help with that too.
Ravioli Explorer's able to extract resources from that since all the other byond extraction tools aren't available. Try using it to open resources.
Even I can use Sql statement with CRUD.In this case, I can show some data to UI easily by some specific change condition. Thanks in advance.
After a few days of research, I find some method. In Linux We can use MongoDB + memory-mapped file, such as tmpfs in Linux. Guide is here, English original and Chinese Translation.
But this is a bit troublesome when relating to Windows, which need help of some tool. If so, that's unnecessary. Write your own file helper honestly manage your data (also for me).
Im starting a new project. The aim of the project is to create a e-authoring tool for building courses in SCORM Complaint. Im new to this domain and I have little idea on this. I have taken a view on authoring tool in Articulate, which my customer requires to do the same. I understood the content creation, but I am trying to understand How can I export this as SCORM compliant course? In between I learned about xAPI as well And understood it is a kind of enhanced SCORM.
Could any one guide me to understand this,
1) How can create content from my custom authoring tool and export as SCORM complaint
2) Is it better to use xAPI or SCORM.
3) How is the SCORM pacakge communicate with my custom made LMS?
4) Heard about LRS,
My custom authoring tool will be made in React and store would MondDB
Any help would be greatly appreciated. Thankyou!
That is a lot to take on, particularly all at once.
1) The SCORM spec is made up of multiple parts. There is a packaging portion and a runtime portion. The basics are that your package needs to be a zip file, and that zip needs to include specific files that indicate to the LMS what type of standard it is along with other metadata about the package. For SCORM this will be called an imsmanifest.xml file. For xAPI you are most likely going to use a cmi5.xml (see cmi5) or a tincan.xml file (what Articulate Storyline exports when it says "xAPI"). The other parts of the package will depend on what standard and version of that standard (for SCORM 1.2, 2004 2nd, 3rd, or 4th edition) you are targeting, realizing that different LMSs support different standards and different degrees of those standards.
Once you have a package constructed that will import, the content itself (usually an HTML file) will need to locate the JavaScript API provided by the SCORM player (from the LMS) and make specific calls depending on what the content is needing to store or read, this is the runtime portion. The calls will again depend on the standard and version. For xAPI based packages (either tincan.xml packages or cmi5 packages) the content will communicate directly to the LRS based on the information provided on the URL at launch time (there is no built in JavaScript API).
2) This entirely depends on what your customer base looks like and the types of data that you intend to capture. SCORM is a more mature landscape and has wider adoption and is more heavily specified, if the information you need to capture fits into its limited information model then it is still an excellent choice. If you need significant data portability and/or the information you need to capture goes beyond compliance data (pass/fail, complete, and score) and/or interaction data (questions + answers) then you should consider xAPI, specifically via cmi5.
3) The LMS must provide a JavaScript API (specified by the SCORM runtime) which the content will use as its interface. The storage/retrieval of data is implementation specific for the LMS beyond what is included in the specification for the JavaScript API.
4) You didn't really include a question here.
I would suggest familiarizing yourself with the two sets of standards via http://scorm.com and http://xapi.com. And although it is a plug for my company's product, you may want to consider the Rustici Driver as it is a product (library) specifically designed to make it easy for an authoring tool to export content as SCORM 1.2, 2004, AICC, cmi5 or Tin Can (the latter two being xAPI). Once you have your tool up and running with minimal standards support you should consider testing it on Rustici's SCORM Cloud (it is free for this purpose), see http://cloud.scorm.com.
The format is huge, there is no quick reference guides. And different authoring tools have different scorm-support depths. You should probably start with this document
Sounds like you're talking about designing editable content; and the content "framework" itself.
This is a massive effort! This is massive support! That said, people do it.
Having built a CMS system for many supporting subject matters I had to divide and conquer this task.
Few ways I'd think to digest this beast- data, data, data
Requirements on Activities (Interaction types)
Design (static/dynamic) on these interactions
The view/facade displaying can change. Tech moves at the speed of light. Need to come up with a super solid data model.
I'd think about how these can be generic, and how they can be extended to meet the customers goals/needs. All depends how much customization (if any) can happen.
I start mapping all this to SCORM CMI Object level calls. Scoring, Progress, Interactions, Objectives etc...
Get your self a wicked SCORM Content API library or write one yourself. You'll be re-using a lot of these calls, no sense baking them into all your interactions
Get up on SCORM Packaging .. much of this has to be defined at author time. Lots of reading, and a lot of features you need to pick thru if your customers even use. Don't dev in places that have .1% market need. The low hanging fruit get you to market.
Surround yourself with passionate great people. You'll need them.
As far as the standards go, it's all about portability. SCORM works directly with a LMS if thats where your customer goes. Others use a LRS which is coded to work with one they set at author time. You can even do both.
Aside from React and MongoDB, you'll need something that can do the lift and shift of all this content.
I'm communicating with a logic analyzer (HP 1660A) over RS232. I issue a command which tells the analyzer to print screen its display and send it over to the controller (my pc) through serial communication. I'm saving the result (which is usually abut 25kB) to my computer and I would like to view it as a TIFF or other format. The problem is that the response from the analyzer comes in PCL format, therefore suitable to be sent to a printer and printed directly, but not to be opened as an image. I have tried a few PCL to image converters to do the job, I found one which does it properly, however I've used the trial version and I am reluctant to purchase it. I've given you the background of my labour. I would appreciate any kind of help, a reference to the commands in pcl 1 and what should I do in order to extract the data and format it properly from the PCL file. I have no experience with PCL and image processing whatsoever, so please, give me a hand here. Thank you.
P.S. I've obtained the PCL file from the analyzer, both in C# and matlab... I have one slight problem in C# with the serial port control, some images have some uninterpreted characters in the image, when using the above converters. I say all these because I need an algorithm or some indications, no matter the programming language, so please feel free to post.
PCL is complex to read. There are only a handful of tools out there that do a good job of this. We have lots of PCL expertise and still often look to other to supply conversion to PDF and other formats. If the PCL is quite simple, that is, just text, a few fonts, and a graphic or two, a couple of RegEx commands could deal with the extraction of the text and then you could mock up a new document using whatever tools you wish.
Looking at these files in stackoverflow might be tough. If you can get them on an ftp and post a link I can take a quick look and post my findings/thoughts here. The other option is to look to an outside tool. There are a few we've had success with. Our needs are broad so I've settled on one that works the best with many different PCL streams (some PCL coding is better than others). As you are dealing with a known quantity of PCL you may have a few options. Here are a few we've used and had some success with (in order of usefulness to us)
PCLWorks by PageTech (they have a GUI viewer and complete SDK)
VeryPDF PCL Converter (command line tool)
SwiftView
There are others, and even an opensource variant of Ghostscript that handles PCL (we've never had much luck as the PCL we use often contains very custom fonts, symbol sets, and tons of macros which seem to choke it.
GhostPCL
EDIT: Most recently we've been working with LincPDF (http://www.lincolnco.com/). This is also an excellent product with has one big benefit, deployment is simple. Some of the other tools have complex software installations. This solution is very easy for us to deploy as a feature in an application. It's also faster then any tools we've tested to date (at least with the PCL that we generate from our apps which is quite complex as they include specialized fonts and macros).
According to the spec sheet for the HP 1660 (pdf) series can send the TIFF,PCX and postscript.
Wouldn't it be easier to use TIFF?
The project was put on hold for a while, but I would like to offer a complete and usable solution.
#Adrian
You can save the image to a floppy disk, I've done that, saved it as TIFF and everything worked fine. Unfortunately, it sends only PCL through RS232. The idea to save the print screen over serial communication was to avoid using too much the floppy disk, which the device uses in order to boot.
#Douglas
Thank you for your elaborate answer. I'll take a look at the indicated tools, however, my desire is to offer a complete front-end solution, which yields directly the graphic. I've put some files from my tests here in order to see the complexity of the PCL constructions. Do you have any knowledge of a possible API that I could integrate into my application, which can parse the file and interpret the PCL?
Regards,
Cosmin
We capture the serial input via a serial spooler that watches COM1:. It's called SSpool.exe. It redirects the PCL as input to PCLXForm. PCLXForm converts it into any raster format (TIFF, JPG, PDF, BMP, etc.) However, we can also extract the text during the conversion and we can extract individual raster objects from the PCL for re-arrangement in the downstream application. Our pricing model is positioned for licensee's that need to convert up to 50,000 pages of invoices into indexed PDF's per month. However, this type of application normally requires a custom license in order to get our pricing down to the level required. In order to do so, we often have to restrict our product to convert unlimited files, but only up to the 20th page within any one PCL print file. That provides enough page volume and gives us the ability to reduce the pricing per unit. To demo, you would need the PCLTool SDK.