While working on a weekend project, Nodejs Image, I decided to obtain an image from the internet to display on my Pebble smartwatch. I wanted to press a button on the watch to get a snapshot of my IP camera on my home network. This allows me to check on my baby via my eye because I can.
Pebble offers sample code that displays a PNG from a web page. The watch can be paired with a smartphone, which downloads the image and sends it to the eye via Bluetooth. The sample code made it easy to get the idea onto your device. However, it was the part I had to figure out how to convert my image to a format that was optimized for Pebble’s screen. Because the My Country Mobile (MCM) between my watch and my phone is very low, optimizing the file size was crucial. This blog post describes my journey to create a Nodejs Image server small enough to format images in the perfect way for my Pebble.
While optimizing an image for a small screen of 180×180 pixels and 64 colors, I found other situations where I could modify an impression “on the fly.” For example, in Nodejs Image, you might create a dynamic thumbnail system to display in a gallery. You might also want to place your studio’s watermark in a more extensive preview from a photo you have taken.
Nodejs Image streams
These types of tasks are made easy by Nodejs Image streams. They allow you to do all your manipulations in RAM and not save an intermediate file on disk. It would be best if you learned more about streams in Node.
An HTTP web request can be made as a stream. This means that you don’t need to have the file you wish to modify on your local filesystem. This is particularly useful for environments that require a quick response, such as Heroku. For example, the original image I want to send is a snapshot from the IP camera’s most recent frame. I would have to request a new picture every time. After providing my username and password, the camera will provide me with the current snapshot in JPEG format.
Putting the streams together
My application will make an HTTP Nodejs Image request for the source file generated by my IP camera when a user agent (in this case, a smartphone) sends an HTTP request. My application will then pipe the stream into an image manipulation stream. It will look something like this:
GraphicsMagick for Nodejs Image
I use the gm module to manipulate the image. You must follow the Nodejs Image instructions to install GraphicsMagick or ImageMagick separately. Homebrew is what I use on my Mac. I run it:
Express is used to create a primary web interface that my user agent can use. Based on the URL’s fileName parameter, I request my source image. Also, My sample code for this blog post substitutes my IP camera for an S3 bucket hosting my static file. see also this business.
So an HTTP GET request to http://localhost:3000/images/IMG_4994.jpg will then make a GET request https://s3.amazonaws.com/nguyer-test/IMG_4994.jpg. The gm module can also stream its results, then piped into the original web request our app received. This is the complete application code:
GraphicsMagick can do almost anything you want to an image. For example, to optimize the photo for display on the Pebble’s screen, I did the following:
- Crop the image to a square, keeping only the most exciting parts.
- It resizes to 180×180 pixels (the resolution on Nodejs Image monitor).
- Increase the contrast
- The Pebble will only display the color palettes that you have chosen. I had a file called SOME_FILE_NAME with the right palette.
- To give the illusion of more colors, distort the image
- Save the final image as a PNG
This was crucial for my project. JPEG has an entirely different file format and encoder, which is incompatible. GraphicsMagick will use the same file format as the input file if you don’t specify one. In this instance, Know more about Engie Digital Customer Service. and we are also Provide a Benefits of E commerce For Customers and Businesses and SwissVoice Ip Phone