I use MATLAB for calculating and plotting purposes. I want to write a plot as a image file like PNG or JPG into a MySQL database (that I can retreive later for a webbrowser). In other words I want to write a blob to the database that is a PNG or JPG file.
If I search for that I get http://www.mathworks.com/matlabcentral/answers/97768-how-do-i-insert-an-image-or-figure-into-a-database-using-the-database-toolbox-in-matlab but here a matrix of MATLAB is written as an array to a database. That is much bigger than a compressed PNG file and thus does not allow to see subplots and other things and cannot be displayed by a webbrowser.
A workaround would be to write the plot to a file and use MATLAB (or a external script tool based on python or so) to read that file as blob and write it as blob to the database.
Do you know a possibility to write a plot as PNG, JPG directly to a databse without the detour of a file?
I also asked the MATLAB support and they gave me an positive answer. A solution is the figToImStream function of MATLAB compiler toolbox: "Stream out figure as byte array encoded in format specified, creating signed byte array in .png format". The downside is that MATLAB compiler toolbox is quite expensive...
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My context
I'm using tesseract to extract text from an image.
I'm generating a .tsv to retrieve the extracted text and perform some regex on it and a .pdf to have a searchable pdf.
The way I do it is by calling tesseract 2 times:
One asking for the .tsv
One asking for the .pdf
But I feel like this is not very efficient (the same computations must be made two times)
What I wish
I wish to make my computations go faster. And my idea is to call tesseract only once but specifying two output formats
Is it possible? If so how?
You can try the command:
tesseract yourimage.tif out pdf tsv
For a project I need to convert my .pdf, .docx or .jpg file into binary file which is consisted of 0 and 1s. This is the way that the computer saves data on the hard for example. Now I also need to be able to bring back the 0,1 info into the aforementioned file type. Can anyone guide me how to do this? Any scripting language is ok but I prefer python or C
A pdf docx or jpg file is already represented in binary (ones and zeros) when stored on your hard disc.
Hence no conversion is necessary.
If you mean something different (for example, conversion to a form that displays on the screen as ones and zeros) then you will need to articulate your question more clearly.
I'm trying to:
load a jpeg through FileReference
write the result to a bytearray
extract the pixel data (and nothing else) directly from the bytearray
I've spent many hours looking for an AS3 class that can decode a jpeg object from raw binary data (such as from a bytearray), but to no avail (there is one here but it relies on Alchemy and a SWC, which isn't suitable).
Put simply, once I have the raw data in the byte array, I'm want to know how to discern the pixel data from the rest of the file.
I'm not interested in using the Loader class, or Bitmap's 'getPixels' function.
you will notice that steganography relies on using a png file. The reason that you can't use the jpg file(easily) is that the encoding process removes the reliability of pixel data. Jpg files can be encoded in several ways, including CMYK and RGB but most often YCbCr. Jpg compression relies on Fourier transform, which will eliminate the pixel-level detail. Therefore you will not be able to use the same process on jpg and png,gif,bmp etc.
This is not to say that you cannot do it in a jpg file, but you need to change the approach, or account for loss of data at compressions stage (or save uncompressed).
Well, you could manipulate the compressed data directly to include your message, but you'd have to read up on how you're able to do it without totally corrupting the image.
But if you're thinking to encode the message in the pixels to do a per-pixel diff when decoding your message I'm afraid your assumption (from the comment on Daniel's answer) is wrong.
JPEG compression is lossy - this means that when you put the amended pixel data back into the image file it which will cause all pixel data to be lost (since it needs to be re-encoded.) Instead of pixel data the only information that's saved in the file is how to reassemble an image that appears very similar looking to the original for the human eye, but the pixel data is not the same.
Not even if you decode the image, then save it as a JPEG file, then do the transformation of the original image and finally save this as a second JPEG with the exact same compression settings can you rely on a per-pixel comparison.
However, as I seem to remember that JPEG compresses the image data in 8*8 pixel blocks, you might be able to manipulate and compare the image data on a per-block basis.
extract the pixel data (and nothing else) directly from the bytearray
To do this you need to decode the jpeg first (apart from some eventual metadata, there is nothing else than pixel data in a typical jpeg file), and the way to do that is precisely using Loader.loadBytes and then BitmapData.getPixels. You can probably make your own decoder (like the one you posted), but I don't see any benefit in doing so.
A guy named Thibault Imbert at ByteArray.org adapted the libjpeg library for ActionScript 3. I have not tested this, but other folks seem to like it by the comments at bytearray.org.
http://code.google.com/p/as3-jpeg-decoder/downloads/list
This is a two part question.
1) Is there any way to get a csv file of all the entity data, including xdata, for an autocad dwg, either using autocad or some other method?
2) Is there an easy way to parse a autocad dxf file to get the entity data into a csv file?
Unfortunately, neither approach provides an easy method, but it is possible with a little effort.
With a DWG file, the file itself is binary so your best bet would be to write a plugin or script to AutoCAD, using .NET or ObjectArx, but this may be a troublesome approach. AutoLISP would be easier, but I don't think you could output to a file.
Getting the enitity data out of a DXF would be significantly easier, since the DXF is primarily a text format. This would be possible with any programming language, but since there are many possible entities it would take some effort to handle all of the cases. The DXF reference is available at the AutoDESK website. XData is certainly also included in the DXF in a text format, so that shouldn't be a problem.
You can write output to a file using autolisp, even binary output with some slight of hand. However, writing dxf data to a csv file, with or without xdata, by either reading the data directly (in-situ) or by parsing a dxf file, is completely impractical, given the nature of dxf group codes and associated data. Perhaps the OP can identify what he wants to achieve, rather than specifying what appears to me to be an inappropriate format for the data.
Michael.
I have a binary file. I don't know how it's formatted, I only know it comes from a delphi code.
Does it exist any way to analyze a binary file?
Does it exist any "pattern" to analyze and deserialize the binary content of a file with unknown format?
Try these:
Deserialize data: analyze how it's compiled your exe (try File Analyzer). Try to deserialize the binary data with the language discovered. Then serialize it in a xml format (language-indipendent) that every programming language can understand
Analyze the binary data: try to save various versions of the file with little variation and use a diff program to analyze the meaning of every bit with an hex editor. Use it in conjunction with binary hacking techniques (like How to crack a Binary File Format by Frans Faase)
Reverse Engineer the application: try getting code using reverse engineering tools for the programming language used for build the app (found with File Analyzer). Otherwise use disassembler analysis tool like IDA Pro Disassembler
For my hobby project I had to reverse engineer some old game files. My approaches were:
Have a good hex editor.
Look for readable words in the binary file. Note how their distribution is. If the distance between them is constant you know it is a listing.
Look for 2-3 consequent zeros. Might indicate an int32 value.
Some dwords might be pointers into the file.
Try to identify reoccurring patterns in the file.
Seeing lots of C0-CF might indicate RLE compressed data.
I've developed Hexinator (Window & Linux) and Synalyze It! (macOS) exactly for this purpose. These applications allow you to see the binary files like in other hex editors but additionally you can create a "grammar" with the specifics of a binary file format. The grammar contains all the building blocks and is used to parse the file automatically.
Thus you can keep the knowledge you gain in the analysis and apply it to multiple files simultaneously. You can also color-code the bits and pieces of file formats for a quick overview in the hex editor.
The parsing results are displayed in a tree view where you can also modify the files easily (applying endianness et cetera).
Reverse engineering a binary file when you have some idea of what it represents is a very time consuming process. If you have no idea what it is then it will be even harder.
It is possible though, but you have to have a pretty good reason for doing so.
The first step would be to open it up in a hex editor of your choice and see if you can find any English text to point you in the direction of what the file is even supposed to represent. From there, Google "Reverse Engineering binary files", there are much more knowledgeable people than me that have written guides about it.
The "strings" program from GNU binutils is very useful. It will print the strings of printable characters in a file, quite often giving a clue to what a file contains or a program does.
If the data represents serialized Delphi objects, you should start reading about the Delphi serialization process. If that's the case, I think your best bet would be to load it using Delphi and continue your analysis from the IDE. Some informations about Delphi serialization can be found here.
EDIT: if the file does contain serialized delphi objects, then you should write a small delphi program that loads it, and "convert" the data yourself to something neutral, like xml. If you manage to do this, you should check and see if delphi supports serializing to xml. Then, you could access those objects from any language.
The unix "file" command is really useful - I don't know if there is anything like it in windows. You run it like this:
file myfile.ext
And it spits out a text description based on the magic numbers and data contained therein.
Probably it is contained within cygwin.
If you have access to the application that creates the file, you can apply changes to the application, then save the file and see the effects (Keep in mind that numbers are probably stored in little endian):
First create the file repeatedly. If the files are not binary equal, the current date/time is probably stored in the area where hte differences occur.
Maybe you want to repeat that with the software running under different environments, to see if OS version etc are stored, but this is rather unusual.
Next you can try to change single variables and create several files that only differ in the value of this variable. This helps you identify where this variable is stored.
That way you can also exclude variables that are not stored in the file: If you change them, but the files created are identical, they are not stored.
In order to test the hypotheses you worked out with the steps above, edit one of the files and have the application read it.
If you don't have access to the application itself, I suggest that you forget about it and find another way to solve your problem. There is a very high probability that it will be faster...
If file does not give a meaningful answer, you may want to try TRiD by Marco Pontello to determine whether your data is stored in a known format.
Get the Delphi application and open it in IDA Pro freeware version, and find where it writes the file, and decode how it writes the file that way.
Unless it's plan text.
Do you know the program that uses it? If so you can hook that programs write to file function and get an idea of what data its writing, the size of the data and where.
More Info: http://www.codeproject.com/KB/DLL/Win32APIHooking_Trouble.aspx
Unlike traditional hex editors which only display the raw hex bytes of a file, 010 Editor can also parse a file into a hierarchical structure using a Binary Template. The results of running a Binary Template are much easier to understand and edit than using just the raw hex bytes.
http://www.sweetscape.com/010editor/
Try to open it in a hex editor and analyse.