Issue saving TIFF file with IStreamWriter under ServiceStack - streaming

I am using the ServiceStack framework to stream a TIFF file.
When I use an IStreamWriter interface, it saves only the first page using an image object.
I am looking for an example of how to use the same stream for a multipage TIFF file.

Related

Evo Pdf adding custom properties to PDF

I am using Evo HTML to PDF library, and trying to find possibility to add custom properties to generated PDF (PDF meta-data - custom properties as key-value).
Does such feature exist in any of your libraries or should I use another library for adding these custom properties to PDF?
Looking through the EVO HTML to PDF converter client documentation, I can't find a reference to the key-value custom properties either.
Workarounds
(Ab)use the Description property of the Document Information class, but I'm not sure if there are (length) limitations).
Attach a file to the PDF with AddFileAttachment.

How to display the images in offline using ionic

I have a gallery module, the functionality implemented in this module as below
- getting the file path from the server using ajaxrequest
- the response will be json object of all image file path
- setting the filepath in image src attribute
As we are using ajax request, the images are loading in online mode only.
so how to implement the functionality so that images should show in offline also.
You may consider returning images as base64 string from the server and store them in a localstorage.
On the view use data-ng-src directive like this .
In your controller check if there is no connection and set base64 string from the localstorage as this: $scope.data.image_url=
After loading an image once, your best bet is going to be get a base64 representation of it, and then persisting that to disk.
Get the base64 representation of the image here:
Get image data in JavaScript?
Write the base64 data to disk using ng-cordova/ionic native and the writeFile method using the Cordova file plugin.
http://ngcordova.com/docs/plugins/file/
writeFile(path, file, data, replace)
There are some great answers here that I would like to build on...
I would suggest using PouchDB as a cache for base64 and/or Blob data after you have downloaded the original (one of my apps does the same thing with mp3 data converted to a Blob). You could then implement a method that checks the cache for the image before making a network request.
Nolan Lawson has created an excellent library for these binary conversions: https://github.com/nolanlawson/blob-util
Just save the base64 string to your PouchDB instance after the initial download, you can then check for that data before your app reaches out to the network.
Just beware of storage limits on iOS Safari (~50mb default)...

How to read PDF file from right to left on iOS

I am working on a basic project that reads pdf files from a server and show them on the screen.
The issue is that i want to read that files from right to left as a page.
Like Massimo Cafaro say :
If you want to extract some content from a pdf file, then you may want to read the following:
Parsing PDF Content
from the Quartz 2D programming guide.
Basically, you will use a CGPDFScanner object to parse the contents, which works as follows. You register a few callbacks that will be automatically invoked by Quartz 2D upon encountering some pdf operators in the pdf stream. After this initial step, you then actually start parsing the pdf stream.
Taking a brief look at your code, it appears that you are not following the steps required to parse the pdf content of the page you get through CGPDFDocumentGetPage(). You need first to setup the callbacks using CGPDFOperatorTableCreate() and CGPDFOperatorTableSetCallback(), then you get the page, you need to create a content stream using that page (using CGPDFContentStreamCreateWithPage()) and then instantiate a CGPDFScanner through CGPDFScannerCreate() and actually start scanning through CGPDFScannerScan().
The "Parsing PDF Content" section of the document pointed out by the above URL gives you all of the information required to implement pdf parsing.
if you don't try anything you can start with this project link

silverstripe upload tiff and convert to jpeg

i´m working on a image database build with silverstripe framework. It needs to be able to upload large tiff files and they should be converted to jpeg. is there a build in function to do that, or do I have to use a library for that?
Regards,
Florian
SilverStripe doesn't have built-in image conversion utilities, just a GD class which mainly handles resizing of existing images (in gif/jpg/png).
ImageMagick supports conversion of TIFFs (see supported formats). I'm sure you can find PHP wrapper libraries for it (doesn't have to be specific to SilverStripe), or use the commandline tool directly via exec().
Other than that, we have the UploadField class to handle uploads. It uses the jQuery fileupload plugin, which supports larger files (although server timeouts and PHP config play a role here as well). You might want to look into chunked uploads.

xlsx database ios

I'm writing an iphone application that pulls xlsx file from the server, manipulates with it (reading and writing to it) and upload it to the server. So I need to convert it to plist format, do some operations with plist and convert plist back to xlsx and upload it to server.
How the convertion xlsx->plist and plist->xlsx could be done on ios?
Here's what you will need to achieve your task:
Note: You must do the heavy lifting
To parse an xlsx, you will need to understand the Open XML file formats: Link
To parse a plist, you will need to understand the Property List file format: Link
To parse, I recommend using the NSXMLParser: Link