Webcam using Javascript and Servlet backend - javascript

Its really good to see that someone has converted JpegCam( project to integrate webcam in a web page http://code.google.com/p/jpegcam/ ) php code into java http://ashwinrayaprolu.wordpress.com/2011/05/26/capture-picture-on-webpage-with-java-backend/ .
I am also building an application in which i have to use web cam on CLIENT SIDE and store the images in DATABASE on SERVER SIDE.. My problem is that how can i refer to the image being clicked since the URL we get after capturing the image is for the server side and i cannot access that image on the server through that URL.
How can i access image in database entry page?
I know its not a good practice to store images in a database but i really don't know how to avoid it.
Please Help..!
Thanks!

Related

Is there a onclick function that will give me a idea of how to display an image after searching it in a sql server?

I have a web application where I need to be able to search a database by ID and the image that is stored on that ID is showed in a preview box. I'm not sure how to get the image to preview somewhere else on the page. I was thinking it would be a onclick event.
I'm using Sql server and I'm new to using sql server for web applications.
When using SQL server you need a server side application, which cannot be done alone with JavaScript. You can make an AJAX call to your server which can return the image in Base64 form where then you can change the src of your image.

Load server database to webpage

currently I have my html5 webpage in a server I have. I have tested the connection and all works find. Now, I want to make a database that is stored in the server, let's say I have: (I'm learning web development )
dir/
index.html
my_db.sql
So the client will ask the server to make a query, delete data or insert data.
I'd like to use javascript for this. Dont know if it is possible. I have search but I only found information on how to make a local database in the client, have been ours looking for this without any result. Thanks

Using a server to send/receive information between a mobile phone and web page

I am trying to set up a simple set up as follows:
Have a mobile app with a page consisting of 4 lines (4 html paragraph lines (I am using phonegap)).
I want to use a web page from which I will input the data for those 4 lines. This information is sent to a server and that server transfers this information to that app on that mobile phone. Now, those 4 lines on the mobile phone is filled with the new information.
Similarly user inputs information on another page consisting of 10 lines of li (list). This information is again sent to the server and to the web page where the information is displayed.
I can almost feel the "internet police guys" getting all hyped and ready to vote this question down. But please understand that I have been on this site and various forums desperate to find a tutorial to guide me to do this and not able to find.
I am trying to use ajax to perform this setup. Confused how I would be using the php file. Information such as password n username is going to go in that php file to connect to the server. But php is a server side script thus needs to sit at the public_html folder. How do I use the php file from my desktop? Write a separate javascript to access it?
It is the concept that is confusing me. I am familiar with html,js,php.
I would appreciate any guidance or maybe a link to a tutorial which would help me to do the concept I mentioned. Thanks for listening.
You will need to create an API using PHP. This API is uploaded to your server and is considered "RESTful". Google a tutorial for what fits your needs. You can set all sorts of rules in this API such as requiring any requests to have an ID or access token.
Since you are using PhoneGap, your HTML and JS files rest on the device, so you will need to allow permissions to your API from anywhere. For this you will have to speak to your host provider about unless you know how to configure it yourself (some providers restrict what you want to do by default as an extra security precaution against XSS attacks).
Next, you can either use jQuery, or you can write some AJAX calls by writing the JavaScript yourself.
The most efficient way for this to work is to send JSON objects to and from the API. You will include a "command" in the JSON when you are sending from your app. On the PHP side, you will retrieve this command and use the rest of the data included in your JSON object to process the request. Your API will need to encode a JSON object for return (such as a user's profile information).
Here is a basic PHP API tutorial to get you going that explains some of the features of a RESTful API: PHP API
Here is a simple AJAX function (you will probably want to make this much more modular): AJAX
As broad as your question is, it seems like the best/easiest thing for you to do will be for you to first create a PHP webpage that will access a SQL database to perform the record updating. Actually, this should serve all of your needs for your mobile users assuming you don't need push notifications for live data updates.
I am assuming, since you are using phone gap, that you are more comfortable with web languages. After you get the webpage fully operational, then you should start building your app based on that exact same SQL database. With mobile app development there are a lot more "what if's" (what if the phone rings, what if the app is running in the background, what if there is no cellular service, etc...)
It is always easier to start with what you know and build on that, rather than starting with a new development platform and troubleshooting as problems arise.

Phonegap app - How to get images from Json Web Service Response?

I need to get images from server side in a Phonegap App. This app uses a Json Web Service to get data from the a .NET application (Server). I need to get images via web services and store in some location of device (temporally). Im asking the first thing. Im thinking what the way to do that is taking via ws the urls of the images, but I need then a way to use the url of image to"download" or get it via url and save to some object or something in Javascript (I guess) for in the case that the device lose the internet connection, the app remains the images getted.
What do you think about this approach and do you know how I can do this way?
Thanks!
As per my understanding for your question you want to download the image... For this you can make use of Cordova file plugin.
Secondly you can keep the image inside your project as well.

Reading and writing to an external file using javascript?

I have an online storage account that I`m using for my homepage. Basically I have just made an "index.html" and stored there . and no php , asp is possible .
So If I must create a message form on the homepage and store the message in a separate text file in JSON format ,can it be done using javascript ?
also I need to query the Text file whenver I want to display the messages using javascript .
So far , I tried TaffyDB but realised it doesn`t have a way to persist the data after session closes. or maybe I missed something?
Thanks!
Short answer. No.
The JavaScript is client side. So it can do all sorts of cool stuff on the persons computer that visits your site but unless you're running some server side code that takes the JSON encoded data and does something with it then you're out of luck.
There are many alternatives.
If you don't want to run your own server side code then you could use a separate service like Parse.com that does REST and has a comprehensive API.
A mobile website can access Parse data from Javascript.
A webserver can show data from Parse on a website.
You can upload large amounts of data that will later be consumed in a mobile app.
You can download recent data to run your own custom analytics.
Applications written in any programming language can interact with data on Parse.
You can export all of your data if you no longer want to use Parse.
You can try with jQuery/AJAX. To read:
$.get("path_to_file", null, function(fileData) {
alert(fileData);
/* Your code goes here */
}, "text");
But in order to write, I think the only way is with some server-side language (PHP, ASP, etc)
The short answer is no.
You need to have some server-side support to persist the data on that server. You can, however, use client-side javascript to relay the information to a server that DOES support reading and writing of the data of course.
Technically, node.js is javascript that does support file reading and writing - but I assume that's out of the question for your environment :)
One crazy way (just as a thought experiment) to implement persistent storage for your web application without server side support is to have the clients talk to each other through P2P. This is possible with Flash or some java applet..etc. So as long as one client is up (perhaps your own comupter!), you'll have some form of persistent storage. Your server/webpage simply serves up this embedded object which does the actual work.

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