I want to add support EXIF for libjpeg library. I read exif2.2 specification briefly, but it does not contain any information about possiblity of exif tag's value, which can be located outside of APP1 marker segment (for example after end of file marker). Is that situation possible?
I maintain the metadata-extractor library, in Java and C#, and have never seen Exif data outside of APP1. It's possible that there are more than one APP1 segments, so you should check for, then skip, the six-byte preamble: Exif\0\0.
If you find a JPEG image that has Exif data outside of the APP1 segment, I'd very much like to know about it!
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How can I make InDesign render a region of a page, as it would be rendered when exporting the whole file?
I know I can render a PageItem using the exportFile function, but this will ignore any other PageItems sharing the same region.
My current solution is to make a new document the size of the region of interest, with a copy of each PageItem whose coordinates fall into that region. It’s very inelegant, and it seems it cannot be done without the user seeing windows meaningless to them come and go.
Another approach I can think of is to export the whole spread containing the region, then crop the resulting file using something like ImageMagick. But I’d still prefer to be able to render only the region I need, if possible.
You can open the InDesing document without showing its UI as well.
app.open(filepath, false);
and while closing the doc, simple use
doc.close(SaveOptions.NO);
You anyways don't need to save that doc on disk.
This will let you have the document open without showing its UI at all.
I did something like this recently. Here are my steps:
duplicate all spread items and group them
make a frame with a proper size/position
cut and paste the group into this frame
export the frame as PNG
If you need another region on this spread you don't need to repeat all the steps, you can change size and position of the frame and to export it again.
There is a limitation: master page items will be omitted.
I am trying to develop a plugin/component that can change the media file format from one to another. Specifically, I need it to convert the "tiff" file to array/single copy of "jpg" image file.
Kindly guide, how I can implement it or is there any kind of tutorial link from where either I can download it or take some help to develop it. Thanks in advance.
We did this in our CMS (built on CakePHP 1.2; sorry if there are any significant discrepancies I'm not aware of) using a behaviour. That makes the controller logic very easy (in fact we use a baked controller without any modification at all).
Unfortunately TIFF isn't a supported file format in GD (the default image manipulation library in PHP). You'll need to use ImageMagick or an equivalent tool to do the actual conversion itself, but the logic for implementing it in your CakePHP project won't be any different to what I describe here.
The behaviour (in our case) was used to generate images as thumbnails as well as page resolution and to convert the uploaded file format into JPEG.
In its beforeSave() method it checked that data was specified (and that there was no error), and then pulled the tmp_name value from the posted data (and removed the posted data object).
In its afterSave() method, it actually performed the image conversion task itself (putting the generated images in the expected location on disk), then updated any foreign keys on extended models with the uploaded image's ID. We do this in the afterSave() operation so we have a database ID to use to name the files on disk.
In its afterDelete() method we unlink the files on disk.
Using the behaviour in the model is as simple as telling the model (where ContentImage is the name of the behaviour):
var $actsAs = array('ContentImage');
Although we also use the model to define the output directory since we had a few models that implemented the behaviour, and it felt like the right thing to do, e.g. in the model:
function getThumbnailDir() {
return WWW_ROOT.'img'.DS.'upload'.DS.'thumb';
}
and in the behaviour itself the output path becomes:
$Model->getThumbnailDir().DS.$Model->id.'.jpg'
I am wondering if there is any available field in the .torrent files that could be used for some custom functionality in someone's implementation of a torrent client? For example, one might want to encode an URL to the file owner's website, someone else - some custom message to be displayed when opening the files, etc. Is something like this feasible in the current implementation of .torrent files?
Yes. .torrent files are just bencoded dictionaries and can hold arbitrary key-value pairs.
The main consideration when adding a custom field is to determine whether it should go into the root of the .torrent or inside the info dictionary.
If it goes into the root, it will not affect the info hash (which is the unique identifier of the torrent), and it will also not be available when downloading magnet links.
If it goes into the info dictionary, it is sort of locked down to the info-hash, in the sense that the info-hash depends on it. It will be transferred as part of the metadata when downloading magnet links and it cannot be changed (without changing the info-hash and thus creating a separate swarm).
So, if it's something you want 3rd parties should be able to change after the torrent was created, it should go in the root, if you want it to be entered once when the torrent is created and never change, it should go in the info dict.
I've been googling around, and all the different answers has got me confused.
In my app I retrieve a contact picture, and put it in an Image object to be displayed to the user.
But I want to save the image to isostorage, and later retrieve it again.
How do I do this?
Can I use the Image.Source for anything?
You cannot get a filename or an ISO storage file.
The only use for ISO storage is to store a file of the bitmap and open a stream to that file to recreate a bitmap later.
The bitmap can then be assigned to the Image.Source.
I have a PDF file where every page is a (LZW) TIFF file. I know this because I created it. I want to be able to load it and save it as a bunch of TIFF files.
I can open the PDF file with CGPDFDocumentCreateWithURL, and get a page. I can even draw the page onto the screen.
What I WANT to do is draw the page into a bitmapContext, so that I can use CGBitmapContextCreateImage to get the image into a CGImageRef. However, in order to create a bitmap context, I need to know the size and resolution of the image. I can't seem to find out how to get either a CGPDFDocument or a CGPDFPage to tell me the resolution of the image object on that page.
Is there an easier way to do this that I'm not realizing?
thanks.
Ghostscript will work for you here :
gs -sDEVICE=tiff32nc -sOutputFile=foo-Page%d.tif foo.pdf
For 2 page document foo.pdf you should get :
foo-Page1.tif
foo-Page2.tif
From memory I think the output resolution from GS is that of the containing Page, not necessarily the resolution of the embedded file (unless these are the same to begin with).
If this is the case and you want to recover the image as it was originally res-wise, you can use iText (java) or iTextSharp(.net) to get to the image content stream (ie. Bytes) and write them out to disk in the format of your choice, after converting the content stream into a PdfImage iirc.
Hope the ghostscript option is applicable to save writing yet another utility...