Reading From a Stream using DotSpatial - dotspatial

Is it possible, using DotSpatial, to read data from a stream (or set of streams) instead of from a specific file? I was hoping that I could point it at the encompassing ZIP file and it'd just work.
I've looked at the Shapefile.Open() and Shapefile.OpenFile() methods, but there doesn't seem to be anything to open ZIP files or multiple streams.

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how to save binarystream as a media file

I have binary asd i want to save as a myvideo.mp4, So my question is that if you have binary and you want to store your file,
So how it would accomplished any one idea i didn't work yet with binary and streaming i am new with these all things so if any one know please share a piece of example which solve my problem.
like response.outStream in this i am getting binary so can i save as a myvideo.mp4 what would be that process actually this binary is generating for mp4 conversion so any idea.
thanks.
You will need to create a FileStream to write to and then you will read the source stream in a loop, reading a block and then writing that block to the FileStream. It should be fairly easy to find an example of reading a stream in a loop using its Read method.

Reading DICOM file formats

I have used Evil DICOM library to read a DICOM file.It is displaying the Raw DICOM file correctly but it is not displaying the other formats.Plz suggest me solution or suggest me any other C# library which reads all the formats correctly.
I assume you are talking about DICOM files with compressed images. You can access the fragments in the pixel data element and uncompress them yourself in Evil Dicom:
DicomFile df = new DicomFile("compressed.dcm");
Fragment[] frags = df.PixelData.Fragments;
but obviously this is more complicated than you probably want. I will try to get the CompressionHelper class running within the next few versions. Many compression formats are proprietary and code for decompression is hard to find.
I believe Grassroots DICOM may be what you are looking for. Not as easy as Evil Dicom, but it supports the formats you want.

Creating a JPEG and writing its EXIF data in Flex

I am creating an application that takes a user's hand signature, input on the Blackberry playbook. When the JPEG is created, I would like to add Exif data such as the date/time to the JPEG. Does anyone know how to do this, or if it is possible?
Thanks
Phil
I couldn't find anything online about writing exif data, but I did find this interesting article on reading exif data. It mentions what bytes does what. I suggest you take that library to create something to write exif data. Seems fairly simple, just need to set the proper tags in the ByteArray, append the image byte array between 2 tags and write to the file.
i found two libries
As3 seems to be writing it to xml, but flash builder does not take in import com.adobe.xmp.*;
Metaphile

Asynchronous use of webclient to transfer files

I have an objective to transfer some files which can be pdf, jpg and xml from one location to another. I am creating a handler based API for that. What could be the best approach for doing it? Should i return a byte array so that the client can pick the byte array and convert it back to file? Also the max file size I need to handle is 18 MB, so i have to make sure that the sizes are properly handled. Should I do an asynchronous transfer for that? If there is some sample code available it would be great.
i got it done using this: http://blog.net-tutorials.com/2009/03/16/how-to-download-a-file-from-the-internet-with-c/ but it has another issue which i mentioned in another question here:
WebClient.DownloadFileAsync downloading the file on server

Is it possible to read music file metadata using R?

I've got a bunch of audio files (let's say ogg or mp3), with metadata.
I wish to read their metadata into R so to create a data.frame with:
file name
file location
file artist
file album
etc
Any way you know of for doing that ?
You take an existing mp3 or ogg client, look at what library it uses and then write a binding for said library to R, using the existing client as guide for that side -- and something like Rcpp as a guide on the other side to show you how to connect C/C++ libraries to R.
No magic bullet.
A cheaper and less reliable way is to use a cmdline tool that does what you want and write little helper functions that use system() to run that tool over the file, re-reading the output in R. Not pretty, not reliable, but possibly less challenging.
Possible, yes, easy, no.
You "could" use a combination of readChar and/or readBin on the file and parse out the contents. This would be highly dependent, though, on parsing the frame tags from the raw bytes of the ID3v2 tag (and mind you it would change if it was a version 1 tag). If would certainly be a lot of work to implement a straight R solution. Take this Python code for example, it's very clean straight python code but a lot of branching and parsing.
You can use exiftool with system command available in R. Optionally, you can create regexp to handle the fields you need... If I were you, I'd stick with Dirk's advice (as usual) =)!
Out here in 2021, I wanted to do this so I did the following...
Create a new playlist while in 'songs' view.
Select all songs and drag to the new playlist. Highlight that playlist
File> Library>Export Playlist. My default file was to save as .txt, if not, designate.
Open Excel to save as csv or read.delim() in r as the txt file is tab-separated
import to R

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