i need an advice on how to approach this problem. I have some picture data: *.jpg, *.bmp ... and i need to extract the data from it. The data is alphanumeric text. I work in delphi.
You will have to head for a OCR (Optical Character Recognition) library. This is a pretty complex procedure, I believe you wouldn't be asking this question if you knew any way to implement this by yourself.
A quick Google yielded this result, maybe it's of help for you:
http://www.planet-source-code.com/vb/scripts/ShowCode.asp?txtCodeId=1623&lngWId=7
Look here:
https://forums.embarcadero.com/message.jspa?messageID=29331
Take a look at my answer about NeuroVCL OCR here. There is a lot of useful info and sample Delphi OCR DCU components.
Related
User needs to parse native-pdf(selectable data, not scanned, no OCR required) in local. The pdf files may be over 400 pages with large tables. Some tables may not have clear borders. Is there any API I could use?
Thanks!
Now that I know you don't want an API, I might recommend that you check out ItextSharp, from nuget. I have used this several times in the past, and there are many stack overflow forums on how to use it. https://www.nuget.org/packages/iTextSharp/5.5.13.1
EDIT: I apologize, it looks like iTextSharp has been replaced with iText 7 https://itextpdf.com/en/products/itext-7
It seems there are several PDF parser APIs out there you could use. PDFTron looks promising, and they offer a free trial: https://www.pdftron.com/pdf-sdk/parsing-library/
DocParser may also be helpful for you, https://docparser.com/features.
I found all of these through a simple google search, so it may benefit you to do some research for yourself. As we can only make broad suggestions based on the information in your question.
I am writing a 'clean-room' program that requires parsing/unparsing of jpegs. I have found all the information I need to parse/unparse baseline jpegs, but I cannot find the information that I need to parse/unparse progressive jpegs.
I need to be able to convert the compressed data to macroblocks and back, so most available frameworks are too high level. I also want to understand what is going on, hence the 'clean room' approach.
Can anybody help me please? A specification of the SOF1 header would be useful, as would be the layout of the compressed data in the scan segment.
Thanks in advance.
If you want to figure this out, I'd get this book:
https://www.amazon.com/Compressed-Image-File-Formats-JPEG/dp/0201604434/ref=sr_1_5?ie=UTF8&qid=1486949641&sr=8-5&keywords=jpeg
It explains it all in easy-to-understand terms. The author has source code at
http://colosseumbuilders.com/sourcecode/imagelib403.zip
that is designed to be easy to understand.
The SOF1 header is the same as all other SOF headers. You need to have a copy of the JPEG standard (as obtuse as it is). The other sources above will help you get through it.
I downloaded the EverNote API Xcode Project but I have a question regarding the OCR feature. With their OCR service, can I take a picture and show the extracted text in a UILabel or does it not work like that?
Or is the text that is extracted not shown to me but only is for the search function of photos?
Has anyone ever had any experience with this or any ideas?
Thanks!
Yes, but it looks like it's going to be a bit of work.
When you get an EDAMResource that corresponds to an image, it has a property called recognition that returns an EDAMData object that contains the XML that defines the recognition info. For example, I attached this image to a note:
I inspected the recognition info that was attached to the corresponding EDAMResource object, and found this:
the xml i found on pastie.org, because it's too big to fit in an answer
As you can see, there's a LOT of information here. The XML is defined in the API documentation, so this would be where you parse the XML and extract the relevant information yourself. Fortunately, the structure of the XML is quite simple (you could write a parser in a few minutes). The hard part will be to figure out what parts you want to use.
It doesn't really work like that. Evernote doesn't really do "OCR" in the pure sense of turning document images into coherent paragraphs of text.
Evernote's recognition XML (which you can retrieve after via the technique that #DaveDeLong shows above) is most useful as an index to search against; the service will provide you sets of rectangles and sets of possible words/text fragments with probability scores attached. This makes a great basis for matching search terms, but a terrible one for constructing a single string that represents the document.
(I know this answer is like 4 years late, but Dave's excellent description doesn't really address this philosophical distinction that you'll run up against if you try to actually do what you were suggesting in the question.)
I'm desperate, I need to convert some jpg images into an animated gif.
I've tried ffmpeg, but the result has a terrible quality.
Also tried imagemagick, and the result looks great but it weights 511 KB !!
Anyone please can tell me what to use or how to use the before applications to get a final animated gif with a normal quality and a normal weight for a gif??
As I said I'm desperate, I need to finish this asap :(
Thanks a lot
Not looking too deeply into the details, this link might have what you are looking for: http://www.somethinkodd.com/oddthinking/2005/12/06/python-imaging-library-pil-and-animated-gifs/, in particular the first link in the comment by Almar on June 16, 2009.
This approach uses the Python and the Python Imaging Library. If you're not handy with either, then it sounds like this approach is going to take longer than you're hoping.
By the way, you might want to ask this question on superuser ... stackoverflow is for programming questions, superuser is more generally about 'doing stuff with computers'.
FIJI or ImageJ do this pretty well. See my answer to an identical SO question here.
I want to use LaTex to write equations faster and if it is possible to export the result as a png or jpg so that it can be used on a website.
Wikipedia (and its opensource wiki engine) uses LaTeX for that, maybe there are some resources available (at least in the code, as it is opensource).
Your question is very broad. You could start with Amazon's List of Latex Books.
You might want to investigate the StackExchange site mathoverflow.net solution - you can read about here. It uses jsMath which supports a lot of LaTeX syntax.
Assuming you already know a little LateX and your primary goal is to get images, a good high-level tool is mathTeX; there are even public servers that will convert to images for you.
If you want to do everything yourself, all the tools use dvipng at bottom.
I like both MathBin.net and Roger's Online Equation Editor. The latter lets you control the quality of the output. See also this question.
try this: http://hausheer.osola.com/latex2png
Here is a small symbol reference for LaTeX. If you are looking for something more as a general introduction, you can look at "The Not So Short Introduction To LaTeX2e". If you use Inkscape, there is built in support for rendering LaTeX and there are also extensions that do the same. You can read some commentary about it here. There are also things like LaTeX to HTML converters; However, at the time I was looking at them, they were somewhat limited in what formulas they could display.
I taught myself LaTeX using the wikibook. It's fairly comprehensive as an initial guide. I've since bought The LaTeX Companion, which is a more advanced guide to in depth typesetting in LaTeX
I use http://www.artofproblemsolving.com/LaTeX/AoPS_L_TeXer.php when I need a quick equation for a web site.
There are packages that will automatically produce images from LaTeX source, but these are often either buggy or used incorrectly. Many people install them on their blogs, for example, and the images show up if you visit the blog directly but they don't show up if you view the page via a blog reader. I'm not saying these problems can't be fixed. They can, but it often takes a few tries.
I prefer just to make a gif and stick it in the page. It's low tech and reliable.
One more tip: it's a good idea to put the LaTeX source in the alt tag of the image. This helps people using screen readers. It helps you too if you need to modify the equation later.
Detextify is a great site that lets you draw a symbol, and it will pop up a list of latex commands that may match your drawing. It's quite accurate! http://detexify.kirelabs.org/classify.html