Merge branch 'master' of https://github.com/esimov/triangle

README.md

@@ -4,8 +4,8 @@
 [![Build Status](https://travis-ci.org/esimov/triangle.svg?branch=master)](https://travis-ci.org/esimov/triangle)
 [![GoDoc](https://godoc.org/github.com/golang/gddo?status.svg)](https://godoc.org/github.com/esimov/triangle)
 [![license](https://img.shields.io/github/license/esimov/triangle)](./LICENSE)
-[![release](https://img.shields.io/badge/release-v1.2.1-blue.svg)](https://github.com/esimov/triangle/releases/tag/v1.2.1)
-![homebrew](https://img.shields.io/badge/homebrew-v1.2.1-orange.svg)
+[![release](https://img.shields.io/badge/release-v1.2.2-blue.svg)](https://github.com/esimov/triangle/releases/tag/v1.2.2)
+![homebrew](https://img.shields.io/badge/homebrew-v1.2.2-orange.svg)
 
 **▲ Triangle** is a tool to generate triangulated image using [delaunay triangulation](https://en.wikipedia.org/wiki/Delaunay_triangulation). It takes a source image and converts it to an abstract image composed of tiles of triangles.
 
@@ -26,33 +26,34 @@ points = tri.GetEdgePoints(sobel, *pointsThreshold, *maxPoints)
 triangles = delaunay.Init(width, height).Insert(points).GetTriangles()
 ```
 
-## Features
+### Features
 
-#### Features implemented
 - [x] Can process recursively whole directories and subdirectories concurrently.
 - [x] Supports various image types.
 - [x] There is no need to specify the file type, the CLI tool can recognize automatically the input and output file type.
+- [x] Can accept image URL as parameter for the `-in` flag.
 - [x] Possibility to save the generated image as an **SGV** file.
 - [x] The generated SVG file can be accessed from the Web browser directly.
-- [x] Clean and intuitive API. The core method responsible with the image triangulation not only that accepts image files but can also work with image data. This means that the `Draw` method can be invoked even on data streams. Check this [demo](https://github.com/esimov/pigo-wasm-demos#face-triangulator) for reference.
-
-#### Features to be implemented
-- [ ] Pipe commands
+- [x] Clean and intuitive API. The API not only that accepts image files but can also work with image data. This means that the [`Draw`](https://github.com/esimov/triangle/blob/65672f53a60a6a35f5e85bed69e46e97fe2d2def/process.go#L82) method can be invoked even on data streams. Check this [demo](https://github.com/esimov/pigo-wasm-demos#face-triangulator) for reference.
+- [x] Support for pipe commands (possibility to pipe in and pipe out the source and destination image).
 
+Head over to this [subtopic](#key-features) to get a better understanding of the supported features.
 
 ## Installation and usage
 ```bash
 $ go get -u -f github.com/esimov/triangle/cmd/triangle
 $ go install
 ```
+You can also download the binary file from the [releases](https://github.com/esimov/triangle/releases) folder.
+
 ## MacOS (Brew) install
-The library can be installed via Homebrew too or by downloading the binary file from the [releases](https://github.com/esimov/triangle/releases) folder.
+The library can be installed via Homebrew too.
 
 ```bash
 $ brew install triangle
 ```
 
-### Supported commands
+## Supported commands
 
 ```bash
 $ triangle --help
@@ -76,6 +77,27 @@ The following flags are supported:
 | `bg` | ' ' | Background color (specified as hex value) |
 | `c` | system spec. | Number of files to process concurrently (workers)
 
+## Key features
+
+#### Process multiple images from a directory concurrently
+The CLI tool also let you process multiple images from a directory **concurrently**. You only need to provide the source and the destination folder by using the `-in` and `-out` flags.
+
+```bash
+$ triangle -in <input_folder> -out <output-folder>
+```
+
+#### Pipe commands
+The CLI tool accepts also pipe commands, which means you can use `stdin` and `stdout` without providing a value for the `-in` and `-out` flag directly since these defaults to `-`. For this reason is possible to use `curl` for example to get an image from the net and invoke the triangulation process over it directly without the need to download the image first and call **▲ Triangle** afterwards.
+
+Here are some examples using pipe names:
+```bash
+$ curl <image_url> | triangle > out.jpg
+$ cat input/source.jpg | triangle > out.jpg
+$ triangle -in input/source.jpg > out.jpg
+$ cat input/source.jpg | triangle -out out.jpg
+$ triangle -out out.jpg < input/source.jpg
+```
+
 #### Background color
 You can specify a background color in case of transparent background images (`.png`) by using the `-bg` flag. This flag accepts a hexadecimal string value. For example setting the flag to `-bg=#ffffff00` will set the alpha channel of the resulted image transparent.
 
@@ -88,20 +110,13 @@ $ triangle -in samples/input.jpg -out output.svg
 
 Using with `-web` flag you can access the generated svg file directly on the web browser.
 
-
 ```bash
 $ triangle -in samples/input.jpg -out output.svg -web=true
 ```
 
 #### Supported output types
-The following output types are supported: `.jpg`, `.jpeg`, `.png`, `.svg`.
+The following output file types are supported: `.jpg`, `.jpeg`, `.png`, `.bmp`, `.svg`.
 
-### Process multiple images from a directory concurrently
-The CLI tool also let you process multiple images from a directory **concurrently**. You only need to provide the source and the destination folder by using the `-in` and `-out` flags.
-
-```bash
-$ triangle -in <input_folder> -out <output-folder>
-```
 ### Tweaks
 Setting a lower points threshold, the resulted image will be more like a cubic painting. You can even add a noise factor, generating a more artistic, grainy image.
 
@@ -111,7 +126,7 @@ $ triangle -in samples/input.jpg -out output.png -wf=0 -pts=3500 -stroke=2 -blur
 $ triangle -in samples/input.jpg -out output.png -wf=2 -pts=5500 -stroke=1 -blur=10
 ```
 
-### Examples
+## Examples
 
 <a href="https://github.com/esimov/triangle/blob/master/output/sample_3.png"><img src="https://github.com/esimov/triangle/blob/master/output/sample_3.png" width=410/></a>
 <a href="https://github.com/esimov/triangle/blob/master/output/sample_4.png"><img src="https://github.com/esimov/triangle/blob/master/output/sample_4.png" width=410/></a>