Lua -> Is it possible to Shrink Larger Image ?
I need it to make thumbnails for jpeg images.
I don't need a "binding". Is there any module writed in pure Lua ?
Is it difficult to write one ?
I have found these:
https://github.com/tnodir/luafreeimage
http://www.tecgraf.puc-rio.br/im/
http://ittner.github.com/lua-gd/manual.html#intro
but they all use C libraries.
Also, do you think it is possible to read Exif Data of Photographs in pure LUA ?
It is possible, but no one has done it, because it is difficult and kindof pointless, since Lua interfaces very nicely with C.
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I have to create a sub routine using VB.Net that compress some files into a "file.zip" file, but the problem is that this "file.zip" MUST have the maximum size of 2 MB.
I don't know how to do it, even if it's possible.
It would be nice if someone has some example to show me.
It is not possible to do this in the general case. For example if you have a 2GB movie file, no lossless compression algorithm will ever get it to 2MB.
One solution is to "chunk" your ZIP file. That is, divide it into parts that are individually no more than 2MB. 7-Zip has support for this. You can use their .NET API from VB.Net. I'm not sure whether the API provides direct support for chunking. If not, you can start 7-Zip from your program using Process.Start().
I just started to look into libGDX and I really enjoyed it. Loading a tile map I generated with an editor was really simple. But I have in mind to work on a game where the player can modify and extend the map.
So here is my question: Is it somehow possible to add/delete/change fields in a com.badlogic.gdx.maps.tiled.TiledMap and save the result to disc?
Unfortunately, right now there is no built-in feature to store TiledMaps.
I know only the .tmx format of TilEd, but this is a pretty easy and straight-forward XML format, which is very similar to the structure of a TiledMap. Check out how TmxMapLoader loads the TiledMap and then use an XmlWriter to write your altered maps to a file in a similar way.
Is there a library function to normalize a sound file? I have searched around but could not find any.
I would like to be able to normalize a sound file and setting that into the sound file so it only needs to be done once rather than on the fly.
Can this be done with Core-Audio?
Yes it can be done, but not with a single function call.
The functionality you want is not in fact CoreAudio, but rather in ExtendedAudioFile.h - part of the AudioToolbox framework. This is available for both iOS and MacOSX. I can attest for this being rather hard to find.
Functions of interest in this header are ExtAudioFileOpenURL(), ExtAudioFileRead() and ExtAudioFileWrite().
In outline what you do:
Use ExtAudioFileOpenURL() to open the input file
Use ExtAudioFileGetProperty() with propertyId kExtAudioFileProperty_FileDataFormat to obtain an AudioStreamBasicDescription describing the file.
Possibly set the ASBD to get the format you want. AudioToolBox on MacOSX seems rather more amenable to this than on iOS.
Calculate an allocate a buffer large enough to hold the entire audio file
Read the entire file with ExtAudioFileRead() - NB: this call might not read it all in one go - operating in much the same was as POSIX read()
Perform normalisation
Use ExtAudioFileCreateWithURL() to create the output file
Use ExtAudioFileWrite() to write the normalised samples out.
Dispose of both audio files.
The documentation links to several example projects that can act as donors of working code. You'll find doing normalisation much easier with the samples as floats, but in iOS, I could never get the conversion to work automatically, so you might have to format convert yourself.
I've been working on an app to create various document formats for a while now, and I've had limited success.
Ideally, I'd like to dynamically create a fairly simple ODT/PDF/DOC file. I've been focusing my efforts on ODT, because it is editable, and open enough that there are several tools which will convert it to any of the other formats I need.
The problem is that the ODT XML files are NOT simple, and there aren't any good-quality API's I could find (especially in python). So far, I've had the most success creating a template ODT file, and then manipulating the DOM in python as needed. This is ok generally, but is quickly becoming inadequate and requires too much tweaking every single time I need to alter one of the templates.
The requirements are:
1) Produce a simple document that will have lists, paragraphs, and the ability to draw simple graphics on the page (boxes, circles, etc...)
2) The ability to specify page size, and the different formats should generally print the exact same output when sent to a printer
My questions:
1) Are there any other ways I can produce ODT/PDF/DOC files?
2) Would LaTeX be acceptable? I've never really used it, does anyone have experience converting LaTeX files into other formats?
3) Would it be possible to use HTML? There are a lot of converters online. Technically you can specify dimensions in mm/cm, etc..., but I am worried that the printed output will differ between browsers/converters....
Any other ideas?
have you tried pandoc? i've been using it with good success for the conversion of different formats into each other. why try to invent the wheel twice?
I suppose to be successful, you'd have to define how you want to input everything. Why don't you just use openoffice? it will save to ODT (duh...), PDF, and HTML (though it's not clean HTML, it's actually quite ugly).
In my recent experience, I've had success going from latex -> xhtml via LaTeXML (i had to compile from source). LaTeX is seeming more and more like a terminal format. It's great for PDF, but once you need some flexibility, it kind of fails. I should also note that there is no latex -> dvi in my workflow, so I can't comment on things like tex4ht that reads out of a dvi file (I have too many graphics that don't work with DVI to switch them now).
Shortly I'll be moving everything into docbook 4.5-- i like the docbook-utils package which supports latex, html, and i even saw a converter to ODT. But docbook is super-heavy on the markup, which is annoying, but it will provide me with the flexibility i need going forward.
Since you're using python, have you just considered using ReStructured Text?
I've also really enjoyed publishing from emacs' orgmode, which is a super light weight markup that goes into a bunch of different formats.
how can I open a PDF file and read some of it's contents with Python (this language is preferred, however Ruby, Perl or PHP are fine too) (in case it is recognized (not just an image)) or report that it's impossible without OCR? TIA
Update: thanks for the solutions, I'm sure some of them will suit me fine.
#RichH, I have a pdf file, and don't know whether it is image- or text-based. I'm looking for a tool to help me find that out and in case it's text-based extract some of it's contents.
For Perl, check out these modules:
PDF::API2
CAM::PDF
Parsing PDF and making something useful out of it is hard as the format is focused on keeping the layout so text can be stored in a way that each letter is positioned individually, depending on the font the text might also be stored as graphic.
libraries to read PDFs I know include the Zend Framework which has a PDF component which includes a PDF parser which can be used from PHP and gives more or less usaable results and the commercial PDFlib which offers quite usable results and offers binding to different languages.