I have a PDF which was encoded using Object Streams. I would like to parse this PDF for further processing with other generated PDFs. Most PDF gems I have used claim Object Streams are not supported.
How have you dealt with parsing object streams?
I am currently using CombinePDF. When I try to load the PDF, CombinePDF chokes on parsing this PDF.
Ideally, I would like to take a PDF which has object streams, remove the object streams, save the PDF as a new PDF file without object streams.
Other gems I've tried, Origami, Yomu, and PDF Reader, all do a lazy parsing.
I know this is possible because I achieved this using Preview on OS X. I opened the said file with Preview on OS X and "Export to PDF…", the new file did not have object streams. How can I reproduce this action in code?
Related
I'm trying to extract JS from PDF files as a requirement of safe upload. Using pdfcpu I can extract pdf's objects by index, but one of the problems is that we're receiving bytes, is there a way to work with that instead of having to write it into a file on disk?
Also, does pdfcpu provides a way for extracting JS in a more declarative manner, instead of having to loop over each object?
This is my first time using Ruby. I'm writing an application that parses data and performs some calculations based on it, the source of which is a JSON file. I'm aware I can use JSON.parse() here but I'm trying to write my program so that it will work with other sources of data. Is there a clear cut way of doing this? Thank you.
When your source file is JSON then use JSON.parse. Do not implement a JSON parser on your own. If the source file is a CSV, then use the CSV class.
When your application should be able to read multiple different formats then just add one Reader class for each data type, like JSONReader, CSVReader, etc. And then decide depending on the file extension which reader to use to read the file.
I know there is an image package that exist in Golang that implements encode and decode functionality, but how can I get other data from an image?. For example I am trying to get iTXt chunks from PNG images, is there any way I can do this?
#Khalil,
Looks like Go's PNG reader does not support ancillary chunks.
Check internals of https://golang.org/src/image/png/reader.go for line 87 and compare with https://www.w3.org/TR/PNG/#5ChunkOrdering.
I want to download data of a specific area from open street map. Whenever I try to export from openstreetmap.org it downloads the data in .osm format but I want the data to be in .pbf format. I have tried converting .osm file to .pbf file using osmconvert.exe but whenever I try to open the converted file in a text editor ( geany to be specific) it shows nothing. But when I tried opening the converted file in vim there was something but not readable. Can someone suggest me a way to download the data of specific area from open street map in readable pbf format?
For downloading area specific OSM files I would like to recommend the service of Geofabrik:
http://download.geofabrik.de/
The format .osm usually is human-readable since it's XML-structured text.
The format .pbf is not human-readable because this is a binary format. PBF-formatted OSM data are highly compressed and need to be converted (for example to .osm or to .csv) before you can read them.
Further information can be found in OSM Wiki:
https://wiki.openstreetmap.org/wiki/OSM_XML
https://wiki.openstreetmap.org/wiki/PBF_Format
I am aiming to combine multiple PDF files each with identical dimensions into one file.
I've seen how it is done with CGPDFContext. I am just curious if there are (better?) alternatives to this method on the Mac.
Let's say I have the option to use PDFs, TIFF, PNG or JPEG files as input. Would using a different input file type mean anything significant for the process, or it would be easier to go with PDF input?
I have use PDFDocument API and it is programmatically easier to use. It may need PDF files as input though.