Bin piping restricted to a special character

Updated Scoop directions

.goreleaser.yml

@@ -30,7 +30,6 @@ builds:
       # - mips64
       # - mips64le
     
-    
 archives:
   -
     name_template: "{{ .ProjectName }}_{{ .Os }}_{{ .Arch }}"

README.md

@@ -1,12 +1,14 @@
 # ascii-image-converter
 
-[![release version](https://img.shields.io/github/v/release/TheZoraiz/ascii-image-converter?label=Latest%20Version)](https://github.com/TheZoraiz/ascii-image-converter/releases/latest)
+[![release-version](https://img.shields.io/github/v/release/TheZoraiz/ascii-image-converter?label=Latest%20Version)](https://github.com/TheZoraiz/ascii-image-converter/releases/latest)
-[![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://github.com/TheZoraiz/ascii-image-converter/blob/master/LICENSE.txt)
+[![license](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://github.com/TheZoraiz/ascii-image-converter/blob/master/LICENSE.txt)
-[![ascii-image-converter-lang](https://img.shields.io/badge/Language-Go-blue)](https://golang.org/) 
+[![language](https://img.shields.io/badge/Language-Go-blue)](https://golang.org/)
-![Github All Releases](https://img.shields.io/github/downloads/TheZoraiz/ascii-image-converter/total?color=brightgreen&label=Release%20Downloads)
+![release-downloads](https://img.shields.io/github/downloads/TheZoraiz/ascii-image-converter/total?color=1d872d&label=Release%20Downloads)
-[![ascii-image-converter](https://snapcraft.io/ascii-image-converter/badge.svg)](https://snapcraft.io/ascii-image-converter)  
+[![ascii-image-converter-snap](https://snapcraft.io/ascii-image-converter/badge.svg)](https://snapcraft.io/ascii-image-converter)
 
-ascii-image-converter is a command-line tool that converts images into ascii art and prints them out onto the console. Available on Windows, Linux and macOS. GIFs are now experimentally supported as well.
+ascii-image-converter is a command-line tool that converts images into ascii art and prints them out onto the console. Available on Windows, Linux and macOS.
+
+Now supports braille art!
 
 Input formats currently supported:
 * JPEG/JPG
@@ -14,14 +16,20 @@ Input formats currently supported:
 * BMP
 * WEBP
 * TIFF/TIF
-* GIF (Experimental)
+* GIF
+
+<p align="center">
+  <img src="https://raw.githubusercontent.com/TheZoraiz/ascii-image-converter/master/example_gifs/all.gif">
+</p>
 
 ## Table of Contents
 
 -  [Installation](#installation)
 	*  [Debian / Ubuntu-based](#debian-or-ubuntu-based-distros)
 	*  [Homebrew](#homebrew)
-	*  [Snap](#brew)
+	*  [AUR](#aur)
+	*  [Scoop](#scoop)
+	*  [Snap](#snap)
 	*  [Go](#go)
 	*  [Linux (binaries)](#linux)
 	*  [Windows (binaries)](#windows)
@@ -34,7 +42,7 @@ Input formats currently supported:
 
 ## Installation
 
-###  Debian or Ubuntu-based Distros
+### Debian or Ubuntu-based Distros
 
 Execute the following commands in order:
 
@@ -52,7 +60,7 @@ sudo apt install -y ascii-image-converter
 To remove the package source (which means you won't be getting any further updates), execute this command:
 
 ```
-sudo rm -rfv /etc/apt/sources.list.d/ascii-image-converter.list
+sudo rm -v /etc/apt/sources.list.d/ascii-image-converter.list
 ```
 
 <hr>
@@ -67,6 +75,36 @@ brew install TheZoraiz/ascii-image-converter/ascii-image-converter
 
 <hr>
 
+### AUR
+
+The AUR repo is maintained by [magnus-tesshu](https://aur.archlinux.org/account/magnus-tesshu)
+
+Standard way:
+```
+git clone https://aur.archlinux.org/ascii-image-converter-git.git
+```
+```
+cd ascii-image-converter-git/
+```
+```
+makepkg -si
+```
+AUR helper:
+```
+<aur-helper> -S ascii-image-converter-git
+```
+<hr>
+
+### Scoop
+
+The scoop manifest is maintained by [brian6932](https://github.com/brian6932)
+
+```
+scoop install ascii-image-converter
+```
+
+<hr>
+
 ### Snap
 
 
@@ -84,7 +122,6 @@ Visit [the app's snap store listing](https://snapcraft.io/ascii-image-converter)
 
 ### Go
 
-For installing through Go
 ```
 go install github.com/TheZoraiz/ascii-image-converter@latest
 ```
@@ -108,8 +145,7 @@ Now you can use ascii-image-converter in the terminal. Execute `ascii-image-conv
 You will need to set an Environment Variable to the folder the ascii-image-converter.exe executable is placed in to be able to use it in the command prompt. Follow the instructions in case of confusion:
 
 Download the archive for your Windows architecture [here](https://github.com/TheZoraiz/ascii-image-converter/releases/latest), extract it, and open the extracted folder. Now, copy the folder path from the top of the file explorer and follow these instructions:
-* In Search, search for and then select: System (Control Panel)
+* In Search, search for and then select: Advanced System Settings
-* Click the Advanced System settings link.
 * Click Environment Variables. In the section User Variables find the Path environment variable and select it. Click "Edit".
 * In the Edit Environment Variable window, click "New" and then paste the path of the folder that you copied initially.
 * Click "Ok" on all open windows.
@@ -131,30 +167,20 @@ Example:
 ```
 ascii-image-converter myImage.jpeg
 ```
-<br>
-Single image:
 
-<p align="center">
+> **Note:** Piped binary input is also supported
-  <img src="https://raw.githubusercontent.com/TheZoraiz/ascii-image-converter/master/example_gifs/base.gif">
+> ```
-</p>
+> cat myImage.png | ascii-image-converter -
+> ```
 
-Multiple images:
-
-<p align="center">
-  <img src="https://raw.githubusercontent.com/TheZoraiz/ascii-image-converter/master/example_gifs/all.gif">
-</p>
-
-GIF:
-
-<p align="center">
-  <img src="https://raw.githubusercontent.com/TheZoraiz/ascii-image-converter/master/example_gifs/gif-example.gif">
-</p>
 
 ### Flags
 
 #### --color OR -C
 
-Display ascii art with the colors from original image. Works with the --negative flag as well.
+> **Note:** Your terminal must support 24-bit or 8-bit colors for appropriate results. If 24-bit colors aren't supported, 8-bit color escape codes will be used
+
+Display ascii art with the colors from original image.
 
 ```
 ascii-image-converter [image paths/urls] -C
@@ -166,6 +192,50 @@ ascii-image-converter [image paths/urls] --color
   <img src="https://raw.githubusercontent.com/TheZoraiz/ascii-image-converter/master/example_gifs/color.gif">
 </p>
 
+#### --braille OR -b
+
+> **Note:** Braille pattern display heavily depends on which terminal or font you're using. In windows, try changing the font from command prompt properties if braille characters don't display
+
+Use braille characters instead of ascii. For this flag, your terminal must support braille patters (UTF-8) properly. Otherwise, you may encounter problems with colored or even uncolored braille art.
+```
+ascii-image-converter [image paths/urls] -b
+# Or
+ascii-image-converter [image paths/urls] --braille
+```
+
+<p align="center">
+  <img src="https://raw.githubusercontent.com/TheZoraiz/ascii-image-converter/master/example_gifs/braille.gif">
+</p>
+
+#### --threshold
+
+Set threshold value to compare for braille art when converting each pixel into a dot. Value must be between 0 and 255.
+
+Example:
+```
+ascii-image-converter [image paths/urls] -b --threshold 170
+```
+
+#### --dither
+
+Apply dithering on image to make braille art more visible. Since braille dots can only be on or off, dithering images makes them more visible in braille art.
+
+Example:
+```
+ascii-image-converter [image paths/urls] -b --dither
+```
+
+<p align="center">
+  <img src="https://raw.githubusercontent.com/TheZoraiz/ascii-image-converter/master/example_gifs/dither.gif">
+</p>
+
+#### --color-bg
+
+If any of the coloring flags is passed, this flag will transfer its color to each character's background. instead of foreground. However, this option isn't available for `--save-img` and `--save-gif`
+```
+ascii-image-converter [image paths/urls] -C --color-bg
+```
+
 #### --dimensions OR -d
 
 > **Note:** Don't immediately append another flag with -d
@@ -337,10 +407,10 @@ Saves the passed GIF as an ascii art GIF with the name `<image-name>-ascii-art.g
 
 > **Note:** This flag will be ignored if `--save-img` or `--save-gif` flags are not set
 
-This flag takes an RGB value that sets the background color in saved png and gif files.
+This flag takes an RGBA value that sets the background color in saved png and gif files. The fourth value (alpha value) is the measure of background opacity ranging between 0 and 100.
 
 ```
-ascii-image-converter [image paths/urls] -s . --save-bg 255,255,255 # For white background
+ascii-image-converter [image paths/urls] -s . --save-bg 255,255,255,100 # For white background
 ```
 
 #### --font
@@ -361,6 +431,14 @@ This flag takes an RGB value that sets the font color in saved png and gif files
 ascii-image-converter [image paths/urls] -s . --font-color 0,0,0 # For black font color
 ```
 
+#### --only-save
+
+Don't print ascii art on the terminal if some saving flag is passed.
+
+```
+ascii-image-converter [image paths/urls] -s . --only-save
+```
+
 #### --formats
 
 Display supported input formats.
@@ -373,14 +451,14 @@ ascii-image-converter --formats
 
 ## Library Usage
 
-> **Note:** The library may throw errors during Go tests due to some unresolved bugs with the [consolesize-go](https://github.com/nathan-fiscaletti/consolesize-go) package (Only during tests, not main program execution). Furthermore, GIF conversion is not advised as it isn't fully library-compatible yet.
+> **Note:** The library may throw errors during Go tests due to some unresolved bugs with the [consolesize-go](https://github.com/nathan-fiscaletti/consolesize-go) package (Only during tests, not main program execution).
 
 First, install the library with:
 ```
 go get -u github.com/TheZoraiz/ascii-image-converter/aic_package
 ```
 
-The library is to be used as follows:
+For an image:
 
 ```go
 package main
@@ -398,23 +476,18 @@ func main() {
 	flags := aic_package.DefaultFlags()
 
 	// This part is optional.
-	// You can directly pass default flags variable to Convert() if you wish.
+	// You can directly pass default flags variable to aic_package.Convert() if you wish.
-	// For clarity, all flags are covered in this example, but you can use specific ones.
+	// There are more flags, but these are the ones shown for demonstration
-	flags.Complex = false // Use complex character set
+	flags.Dimensions = []int{50, 25}
-	flags.Dimensions = []int{50, 25} // 50 by 25 ascii art size
+	flags.Colored = true
-	flags.SaveTxtPath = "."  // Save generated text in same directory
+	flags.SaveTxtPath = "."
-	flags.SaveImagePath = "."  // Save generated PNG image in same directory
+	flags.SaveImagePath = "."
-	flags.SaveGifPath = "." // If gif is provided, save ascii art gif in same directory
+	flags.CustomMap = " .-=+#@"
-	flags.Negative = false  // Ascii art will have negative color-depth
+	flags.FontFilePath = "./RobotoMono-Regular.ttf" // If file is in current directory
-	flags.Colored = true  // Keep colors from original image. This overrides flags.Grayscale and flags.FontColor
+	flags.SaveBackgroundColor = [4]int{50, 50, 50, 100}
-	flags.Grayscale = false // Returns grayscale ascii art. This overrides flags.FontColor
+
-	flags.CustomMap = " .-=+#@"  // Starting from darkest to brightest shades. This overrides flags.Complex
+	// Note: For environments where a terminal isn't available (such as web servers), you MUST
-	flags.FlipX = false  // Flips ascii art horizontally
+	// specify atleast one of flags.Width, flags.Height or flags.Dimensions
-	flags.FlipY = false  // Flips ascii art vertically
-	flags.Full = false  // Display ascii art that fills the terminal width. This overrides flags.Dimensions
-	flags.FontFilePath = "./RobotoMono-Regular.ttf" // File path to font .ttf file for saved png and gif files. Ignored if flags.SaveImagePath or flags.SaveGifPath are not set
-	flags.FontColor = [3]int{0, 0, 0} // Font color for terminal and saved png and gif files.
-	flags.SaveBackgroundColor = [3]int{255, 255, 255} // Font color for saved png and gif files. Ignored if flags.SaveImagePath or flags.SaveGifPath are not set.
 
 	// Conversion for an image
 	asciiArt, err := aic_package.Convert(filePath, flags)
@@ -423,15 +496,34 @@ func main() {
 	}
 
 	fmt.Printf("%v\n", asciiArt)
+}
+```
+<br>
+
+> **Note:** GIF conversion is not advised as the function may run infinitely, depending on the GIF. More work needs to be done on this to make it more library-compatible.
+
+For a GIF:
+
+```go
+package main
+
+import (
+	"fmt"
+
+	"github.com/TheZoraiz/ascii-image-converter/aic_package"
+)
+
+func main() {
+	filePath = "myGif.gif"
+
+	flags := aic_package.DefaultFlags()
 
-	// GIF CONVERSION IS AN EXPERIMENTAL FEATURE
-	// For a gif. This function may run infinitely, depending on the gif
-	// Work needs to be done on gif conversion to be more library-compatible
 	_, err := aic_package.Convert(filePath, flags)
 	if err != nil {
 		fmt.Println(err)
 	}
 }
+
 ```
 
 <br>
@@ -450,11 +542,11 @@ You can fork the project and implement any changes you want for a pull request.
 
 [github.com/nathan-fiscaletti/consolesize-go](https://github.com/nathan-fiscaletti/consolesize-go)
 
-[github.com/nfnt/resize](https://github.com/nfnt/resize)
+[github.com/disintegration/imaging](https://github.com/disintegration/imaging)
 
 [github.com/gookit/color](https://github.com/gookit/color)
 
-[github.com/asaskevich/govalidator](https://github.com/asaskevich/govalidator)
+[github.com/makeworld-the-better-one/dither](https://github.com/makeworld-the-better-one/dither)
 
 ## License
 

aic_package/convert_gif.go

@@ -45,20 +45,26 @@ as an ascii art gif.
 
 Multi-threading has been implemented in multiple places due to long execution time
 */
-func pathIsGif(gifPath, urlImgName string, pathIsURl bool, urlImgBytes []byte, localGif *os.File) (string, error) {
+func pathIsGif(gifPath, urlImgName string, pathIsURl bool, urlImgBytes, pipedInputBytes []byte, localGif *os.File) error {
 
 	var (
 		originalGif *gif.GIF
 		err         error
 	)
 
-	if pathIsURl {
+	if gifPath == "-" {
+		originalGif, err = gif.DecodeAll(bytes.NewReader(pipedInputBytes))
+	} else if pathIsURl {
 		originalGif, err = gif.DecodeAll(bytes.NewReader(urlImgBytes))
 	} else {
 		originalGif, err = gif.DecodeAll(localGif)
 	}
 	if err != nil {
-		return "", fmt.Errorf("can't decode %v: %v", gifPath, err)
+		if gifPath == "-" {
+			return fmt.Errorf("can't decode piped input: %v", err)
+		} else {
+			return fmt.Errorf("can't decode %v: %v", gifPath, err)
+		}
 	}
 
 	var (
@@ -91,19 +97,33 @@ func pathIsGif(gifPath, urlImgName string, pathIsURl bool, urlImgBytes []byte, l
 			// If a frame is found that is smaller than the first frame, then this gif contains smaller subimages that are
 			// positioned inside the original gif. This behavior isn't supported by this app
 			if firstGifFrameWidth != frameImage.Bounds().Dx() || firstGifFrameHeight != frameImage.Bounds().Dy() {
-				fmt.Println("Error: GIF contains subimages smaller than default width and height\nProcess aborted because ascii-image-converter doesn't support subimage placement and transparency in GIFs\n")
+				if urlImgName == "" {
+					fmt.Printf("Error: " + gifPath + " contains subimages smaller than default width and height\n\nProcess aborted because ascii-image-converter doesn't support subimage placement and transparency in GIFs\n\n")
+				} else {
+					fmt.Printf("Error: " + urlImgName + " contains subimages smaller than default width and height\n\nProcess aborted because ascii-image-converter doesn't support subimage placement and transparency in GIFs\n\n")
+				}
 				os.Exit(0)
 			}
 
 			var imgSet [][]imgManip.AsciiPixel
 
-			imgSet, err = imgManip.ConvertToAsciiPixels(frameImage, dimensions, width, height, flipX, flipY, full)
+			imgSet, err = imgManip.ConvertToAsciiPixels(frameImage, dimensions, width, height, flipX, flipY, full, braille, dither)
 			if err != nil {
-				fmt.Println("Error:", err)
+				fmt.Printf("Error: %v\n", err)
+				os.Exit(0)
+			}
+
+			var asciiCharSet [][]imgManip.AsciiChar
+			if braille {
+				asciiCharSet, err = imgManip.ConvertToBrailleChars(imgSet, negative, colored, grayscale, colorBg, fontColor, threshold)
+			} else {
+				asciiCharSet, err = imgManip.ConvertToAsciiChars(imgSet, negative, colored, grayscale, complex, colorBg, customMap, fontColor)
+			}
+			if err != nil {
+				fmt.Printf("Error: %v\n", err)
 				os.Exit(0)
 			}
 
-			asciiCharSet := imgManip.ConvertToAsciiChars(imgSet, negative, colored, complex, customMap, fontColor)
 			gifFramesSlice[i].asciiCharSet = asciiCharSet
 			gifFramesSlice[i].delay = originalGif.Delay[i]
 
@@ -137,12 +157,12 @@ func pathIsGif(gifPath, urlImgName string, pathIsURl bool, urlImgBytes []byte, l
 
 		saveFileName, err := createSaveFileName(gifPath, urlImgName, "-ascii-art.gif")
 		if err != nil {
-			return "", err
+			return err
 		}
 
 		fullPathName, err := getFullSavePath(saveFileName, saveGifPath)
 		if err != nil {
-			return "", fmt.Errorf("can't save file: %v", err)
+			return fmt.Errorf("can't save file: %v", err)
 		}
 
 		// Initializing some constants for gif. Done outside loop to save execution
@@ -182,7 +202,7 @@ func pathIsGif(gifPath, urlImgName string, pathIsURl bool, urlImgBytes []byte, l
 					colored || grayscale,
 				)
 				if err != nil {
-					fmt.Println("Error:", err)
+					fmt.Printf("Error: %v\n", err)
 					os.Exit(0)
 				}
 
@@ -219,34 +239,38 @@ func pathIsGif(gifPath, urlImgName string, pathIsURl bool, urlImgBytes []byte, l
 
 		gifFile, err := os.OpenFile(fullPathName, os.O_WRONLY|os.O_CREATE, 0666)
 		if err != nil {
-			return "", fmt.Errorf("can't save file: %v", err)
+			return fmt.Errorf("can't save file: %v", err)
 		}
 		defer gifFile.Close()
 
 		gif.EncodeAll(gifFile, outGif)
 
 		fmt.Printf("                     \r")
+
+		fmt.Println("Saved " + fullPathName)
 	}
 
 	// Display the gif
-	loopCount := 0
+	if !onlySave {
-	for {
+		loopCount := 0
-		for i, asciiFrame := range asciiArtSet {
+		for {
-			clearScreen()
+			for i, asciiFrame := range asciiArtSet {
-			fmt.Println(asciiFrame)
+				clearScreen()
-			time.Sleep(time.Duration((time.Second * time.Duration(originalGif.Delay[i])) / 100))
+				fmt.Println(asciiFrame)
-		}
+				time.Sleep(time.Duration((time.Second * time.Duration(originalGif.Delay[i])) / 100))
+			}
 
-		// If gif is infinite loop
+			// If gif is infinite loop
-		if originalGif.LoopCount == 0 {
+			if originalGif.LoopCount == 0 {
-			continue
+				continue
-		}
+			}
 
-		loopCount++
+			loopCount++
-		if loopCount == originalGif.LoopCount {
+			if loopCount == originalGif.LoopCount {
-			break
+				break
+			}
 		}
 	}
 
-	return "", nil
+	return nil
 }

aic_package/convert_image.go

@@ -27,28 +27,43 @@ import (
 )
 
 // This function decodes the passed image and returns an ascii art string, optionaly saving it as a .txt and/or .png file
-func pathIsImage(imagePath, urlImgName string, pathIsURl bool, urlImgBytes []byte, localImg *os.File) (string, error) {
+func pathIsImage(imagePath, urlImgName string, pathIsURl bool, urlImgBytes, pipedInputBytes []byte, localImg *os.File) (string, error) {
 
 	var (
 		imData image.Image
 		err    error
 	)
 
-	if pathIsURl {
+	if imagePath == "-" {
+		imData, _, err = image.Decode(bytes.NewReader(pipedInputBytes))
+	} else if pathIsURl {
 		imData, _, err = image.Decode(bytes.NewReader(urlImgBytes))
 	} else {
 		imData, _, err = image.Decode(localImg)
 	}
 	if err != nil {
-		return "", fmt.Errorf("can't decode %v: %v", imagePath, err)
+		if imagePath == "-" {
+			return "", fmt.Errorf("can't decode piped input: %v", err)
+		} else {
+			return "", fmt.Errorf("can't decode %v: %v", imagePath, err)
+		}
 	}
 
-	imgSet, err := imgManip.ConvertToAsciiPixels(imData, dimensions, width, height, flipX, flipY, full)
+	imgSet, err := imgManip.ConvertToAsciiPixels(imData, dimensions, width, height, flipX, flipY, full, braille, dither)
 	if err != nil {
 		return "", err
 	}
 
-	asciiSet := imgManip.ConvertToAsciiChars(imgSet, negative, colored, complex, customMap, fontColor)
+	var asciiSet [][]imgManip.AsciiChar
+
+	if braille {
+		asciiSet, err = imgManip.ConvertToBrailleChars(imgSet, negative, colored, grayscale, colorBg, fontColor, threshold)
+	} else {
+		asciiSet, err = imgManip.ConvertToAsciiChars(imgSet, negative, colored, grayscale, complex, colorBg, customMap, fontColor)
+	}
+	if err != nil {
+		return "", err
+	}
 
 	// Save ascii art as .png image before printing it, if --save-img flag is passed
 	if saveImagePath != "" {
@@ -58,6 +73,7 @@ func pathIsImage(imagePath, urlImgName string, pathIsURl bool, urlImgBytes []byt
 			saveImagePath,
 			imagePath,
 			urlImgName,
+			onlySave,
 		); err != nil {
 
 			return "", fmt.Errorf("can't save file: %v", err)
@@ -71,6 +87,7 @@ func pathIsImage(imagePath, urlImgName string, pathIsURl bool, urlImgBytes []byt
 			imagePath,
 			saveTxtPath,
 			urlImgName,
+			onlySave,
 		); err != nil {
 
 			return "", fmt.Errorf("can't save file: %v", err)
@@ -80,5 +97,8 @@ func pathIsImage(imagePath, urlImgName string, pathIsURl bool, urlImgBytes []byt
 	ascii := flattenAscii(asciiSet, colored || grayscale, false)
 	result := strings.Join(ascii, "\n")
 
+	if onlySave {
+		return "", nil
+	}
 	return result, nil
 }

aic_package/convert_root.go

@@ -32,10 +32,17 @@ import (
 	_ "golang.org/x/image/tiff"
 	_ "golang.org/x/image/webp"
 
-	"github.com/asaskevich/govalidator"
 	"github.com/golang/freetype/truetype"
 )
 
+var pipedInputTypes = []string{
+	"image/png",
+	"image/jpeg",
+	"image/webp",
+	"image/tiff",
+	"image/bmp",
+}
+
 // Return default configuration for flags.
 // Can be sent directly to ConvertImage() for default ascii art
 func DefaultFlags() Flags {
@@ -49,6 +56,7 @@ func DefaultFlags() Flags {
 		SaveGifPath:         "",
 		Negative:            false,
 		Colored:             false,
+		CharBackgroundColor: false,
 		Grayscale:           false,
 		CustomMap:           "",
 		FlipX:               false,
@@ -56,7 +64,11 @@ func DefaultFlags() Flags {
 		Full:                false,
 		FontFilePath:        "",
 		FontColor:           [3]int{255, 255, 255},
-		SaveBackgroundColor: [3]int{0, 0, 0},
+		SaveBackgroundColor: [4]int{0, 0, 0, 100},
+		Braille:             false,
+		Threshold:           128,
+		Dither:              false,
+		OnlySave:            false,
 	}
 }
 
@@ -80,6 +92,7 @@ func Convert(filePath string, flags Flags) (string, error) {
 	saveGifPath = flags.SaveGifPath
 	negative = flags.Negative
 	colored = flags.Colored
+	colorBg = flags.CharBackgroundColor
 	grayscale = flags.Grayscale
 	customMap = flags.CustomMap
 	flipX = flags.FlipX
@@ -88,43 +101,87 @@ func Convert(filePath string, flags Flags) (string, error) {
 	fontPath = flags.FontFilePath
 	fontColor = flags.FontColor
 	saveBgColor = flags.SaveBackgroundColor
+	braille = flags.Braille
+	threshold = flags.Threshold
+	dither = flags.Dither
+	onlySave = flags.OnlySave
+
+	inputIsGif = path.Ext(filePath) == ".gif"
 
 	// Declared at the start since some variables are initially used in conditional blocks
 	var (
-		localFile   *os.File
+		localFile       *os.File
-		urlImgBytes []byte
+		urlImgBytes     []byte
-		urlImgName  string = ""
+		urlImgName      string = ""
-		err         error
+		pipedInputBytes []byte
+		err             error
 	)
 
-	pathIsURl := govalidator.IsRequestURL(filePath)
+	pathIsURl := isURL(filePath)
 
 	// Different modes of reading data depending upon whether or not filePath is a url
-	if pathIsURl {
-		fmt.Printf("Fetching file from url...\r")
 
-		retrievedImage, err := http.Get(filePath)
+	if filePath != "-" {
-		if err != nil {
+		if pathIsURl {
-			return "", fmt.Errorf("can't fetch content: %v", err)
+			fmt.Printf("Fetching file from url...\r")
+
+			retrievedImage, err := http.Get(filePath)
+			if err != nil {
+				return "", fmt.Errorf("can't fetch content: %v", err)
+			}
+
+			urlImgBytes, err = ioutil.ReadAll(retrievedImage.Body)
+			if err != nil {
+				return "", fmt.Errorf("failed to read fetched content: %v", err)
+			}
+			defer retrievedImage.Body.Close()
+
+			urlImgName = path.Base(filePath)
+			fmt.Printf("                          \r") // To erase "Fetching image from url..." text from terminal
+
+		} else {
+
+			localFile, err = os.Open(filePath)
+			if err != nil {
+				return "", fmt.Errorf("unable to open file: %v", err)
+			}
+			defer localFile.Close()
+
 		}
 
-		urlImgBytes, err = ioutil.ReadAll(retrievedImage.Body)
-		if err != nil {
-			return "", fmt.Errorf("failed to read fetched content: %v", err)
-		}
-		defer retrievedImage.Body.Close()
-
-		urlImgName = path.Base(filePath)
-		fmt.Printf("                          \r") // To erase "Fetching image from url..." text from terminal
-
 	} else {
+		// Check file/data type of piped input
 
-		localFile, err = os.Open(filePath)
+		if !isInputFromPipe() {
-		if err != nil {
+			return "", fmt.Errorf("there is no input being piped to stdin")
-			return "", fmt.Errorf("unable to open file: %v", err)
 		}
-		defer localFile.Close()
 
+		pipedInputBytes, err = ioutil.ReadAll(os.Stdin)
+		if err != nil {
+			return "", fmt.Errorf("unable to read piped input: %v", err)
+		}
+
+		fileType := http.DetectContentType(pipedInputBytes)
+		invalidInput := true
+
+		if fileType == "image/gif" {
+			inputIsGif = true
+			invalidInput = false
+
+		} else {
+			for _, inputType := range pipedInputTypes {
+				if fileType == inputType {
+					invalidInput = false
+					break
+				}
+			}
+		}
+
+		// Not sure if I should uncomment this.
+		// The output may be piped to another program and a warning would contaminate that
+		if invalidInput {
+			// fmt.Println("Warning: file type of piped input could not be determined, treating it as an image")
+		}
 	}
 
 	// If path to font file is provided, use it
@@ -138,11 +195,13 @@ func Convert(filePath string, flags Flags) (string, error) {
 		if tempFont, err = truetype.Parse(fontFile); err != nil {
 			return "", fmt.Errorf("unable to parse font file: %v", err)
 		}
+	} else if braille {
+		tempFont, _ = truetype.Parse(embeddedDejaVuObliqueFont)
 	}
 
-	if path.Ext(filePath) == ".gif" {
+	if inputIsGif {
-		return pathIsGif(filePath, urlImgName, pathIsURl, urlImgBytes, localFile)
+		return "", pathIsGif(filePath, urlImgName, pathIsURl, urlImgBytes, pipedInputBytes, localFile)
 	} else {
-		return pathIsImage(filePath, urlImgName, pathIsURl, urlImgBytes, localFile)
+		return pathIsImage(filePath, urlImgName, pathIsURl, urlImgBytes, pipedInputBytes, localFile)
 	}
 }

aic_package/create_ascii_gif.go

@@ -88,11 +88,6 @@ func createGifFrameToSave(asciiArt [][]imgManip.AsciiChar, img image.Image, colo
 
 	dc.DrawImage(tempImg, 0, 0)
 
-	// Load embedded font
-	tempFont, err := truetype.Parse(embeddedFontFile)
-	if err != nil {
-		return nil, err
-	}
 	// Font size increased during assignment to become more visible. This will not affect image drawing
 	fontFace := truetype.NewFace(tempFont, &truetype.Options{Size: fontSize * 1.5})
 

aic_package/create_ascii_image.go

@@ -17,6 +17,7 @@ limitations under the License.
 package aic_package
 
 import (
+	"fmt"
 	"image"
 	"image/color"
 
@@ -28,13 +29,16 @@ import (
 )
 
 //go:embed Hack-Regular.ttf
-var embeddedFontFile []byte
+var embeddedHackRegularFont []byte
+
+//go:embed DejaVuSans-Oblique.ttf
+var embeddedDejaVuObliqueFont []byte
 
 var tempFont *truetype.Font
 
 // Load embedded font
 func init() {
-	tempFont, _ = truetype.Parse(embeddedFontFile)
+	tempFont, _ = truetype.Parse(embeddedHackRegularFont)
 }
 
 /*
@@ -45,7 +49,7 @@ images will considerably decrease ascii art quality because of smaller font size
 
 Size of resulting image may also be considerably larger than original image.
 */
-func createImageToSave(asciiArt [][]imgManip.AsciiChar, colored bool, saveImagePath, imagePath, urlImgName string) error {
+func createImageToSave(asciiArt [][]imgManip.AsciiChar, colored bool, saveImagePath, imagePath, urlImgName string, onlySave bool) error {
 
 	constant := 14.0
 
@@ -70,10 +74,11 @@ func createImageToSave(asciiArt [][]imgManip.AsciiChar, colored bool, saveImageP
 	dc := gg.NewContext(imgWidth, imgHeight)
 
 	// Set image background
-	dc.SetRGB(
+	dc.SetRGBA(
 		float64(saveBgColor[0])/255,
 		float64(saveBgColor[1])/255,
 		float64(saveBgColor[2])/255,
+		float64(saveBgColor[3])/100,
 	)
 	dc.Clear()
 
@@ -135,5 +140,9 @@ func createImageToSave(asciiArt [][]imgManip.AsciiChar, colored bool, saveImageP
 		return err
 	}
 
+	if onlySave {
+		fmt.Println("Saved " + fullPathName)
+	}
+
 	return dc.SavePNG(fullPathName)
 }

aic_package/readme.md

@@ -0,0 +1,3 @@
+## Note
+
+The font `DejaVuSans-Oblique.ttf` is used for saving braille art .png images since it supports unicode and gave the best results. `Hack-Regular.ttf` is used for saving normal ascii art .png images.

aic_package/util.go

@@ -28,7 +28,7 @@ import (
 	imgManip "github.com/TheZoraiz/ascii-image-converter/image_manipulation"
 )
 
-func saveAsciiArt(asciiSet [][]imgManip.AsciiChar, imagePath, savePath, urlImgName string) error {
+func saveAsciiArt(asciiSet [][]imgManip.AsciiChar, imagePath, savePath, urlImgName string, onlySave bool) error {
 	// To make sure uncolored ascii art is the one saved as .txt
 	saveAscii := flattenAscii(asciiSet, false, true)
 
@@ -46,7 +46,13 @@ func saveAsciiArt(asciiSet [][]imgManip.AsciiChar, imagePath, savePath, urlImgNa
 
 	// If path exists
 	if _, err := os.Stat(savePath); !os.IsNotExist(err) {
-		return ioutil.WriteFile(savePath+saveFileName, []byte(strings.Join(saveAscii, "\n")), 0666)
+		err := ioutil.WriteFile(savePath+saveFileName, []byte(strings.Join(saveAscii, "\n")), 0666)
+		if err != nil {
+			return err
+		} else if onlySave {
+			fmt.Println("Saved " + savePath + saveFileName)
+		}
+		return nil
 	} else {
 		return fmt.Errorf("save path %v does not exist", savePath)
 	}
@@ -61,6 +67,13 @@ func createSaveFileName(imagePath, urlImgName, label string) (string, error) {
 		return newName + label, nil
 	}
 
+	if imagePath == "-" {
+		if inputIsGif {
+			return "piped-gif" + label, nil
+		}
+		return "piped-img" + label, nil
+	}
+
 	fileInfo, err := os.Stat(imagePath)
 	if err != nil {
 		return "", err
@@ -79,24 +92,24 @@ func flattenAscii(asciiSet [][]imgManip.AsciiChar, colored, toSaveTxt bool) []st
 	var ascii []string
 
 	for _, line := range asciiSet {
-		var tempAscii []string
+		var tempAscii string
 
-		for i := 0; i < len(line); i++ {
+		for _, char := range line {
 			if toSaveTxt {
-				tempAscii = append(tempAscii, line[i].Simple)
+				tempAscii += char.Simple
 				continue
 			}
 
 			if colored {
-				tempAscii = append(tempAscii, line[i].OriginalColor)
+				tempAscii += char.OriginalColor
 			} else if fontColor != [3]int{255, 255, 255} {
-				tempAscii = append(tempAscii, line[i].SetColor)
+				tempAscii += char.SetColor
 			} else {
-				tempAscii = append(tempAscii, line[i].Simple)
+				tempAscii += char.Simple
 			}
 		}
 
-		ascii = append(ascii, strings.Join(tempAscii, ""))
+		ascii = append(ascii, tempAscii)
 	}
 
 	return ascii
@@ -119,6 +132,15 @@ func getFullSavePath(imageName, saveFilePath string) (string, error) {
 	}
 }
 
+func isURL(urlString string) bool {
+	if len(urlString) < 8 {
+		return false
+	} else if urlString[:7] == "http://" || urlString[:8] == "https://" {
+		return true
+	}
+	return false
+}
+
 // Following is for clearing screen when showing gif
 var clear map[string]func()
 
@@ -146,3 +168,8 @@ func clearScreen() {
 		os.Exit(0)
 	}
 }
+
+func isInputFromPipe() bool {
+	fileInfo, _ := os.Stdin.Stat()
+	return fileInfo.Mode()&os.ModeCharDevice == 0
+}

aic_package/vars.go

@@ -50,12 +50,17 @@ type Flags struct {
 	// This overrides Flags.Grayscale and Flags.FontColor
 	Colored bool
 
+	// If Flags.Colored, Flags.Grayscale or Flags.FontColor is set, use that color
+	// on each character's background in the terminal
+	CharBackgroundColor bool
+
 	// Keep grayscale colors from the original image. This uses the True color
 	// codes for the terminal and will work on saved .png and .gif files as well
 	// This overrides Flags.FontColor
 	Grayscale bool
 
 	// Pass custom ascii art characters as a string.
+	// e.g. " .-=+#@".
 	// This overrides Flags.Complex
 	CustomMap string
 
@@ -73,13 +78,30 @@ type Flags struct {
 	// This will be ignored if Flags.SaveImagePath or Flags.SaveGifPath are not set
 	FontFilePath string
 
-	// Font RGB color in saved png or gif files.
+	// Font RGB color for terminal display and saved png or gif files.
-	// This will be ignored if Flags.SaveImagePath or Flags.SaveGifPath are not set
 	FontColor [3]int
 
 	// Background RGB color in saved png or gif files.
 	// This will be ignored if Flags.SaveImagePath or Flags.SaveGifPath are not set
-	SaveBackgroundColor [3]int
+	SaveBackgroundColor [4]int
+
+	// Use braille characters instead of ascii. Terminal must support UTF-8 encoding.
+	// Otherwise, problems may be encountered with colored or even uncolored braille art.
+	// This overrides Flags.Complex and Flags.CustomMap
+	Braille bool
+
+	// Threshold for braille art if Flags.Braille is set to true. Value provided must
+	// be between 0 and 255. Ideal value is 128.
+	// This will be ignored if Flags.Braille is not set
+	Threshold int
+
+	// Apply FloydSteinberg dithering on an image before ascii conversion. This option
+	// is meant for braille art. Therefore, it will be ignored if Flags.Braille is false
+	Dither bool
+
+	// If Flags.SaveImagePath, Flags.SaveTxtPath or Flags.SaveGifPath are set, then don't
+	// print on terminal
+	OnlySave bool
 }
 
 var (
@@ -93,11 +115,17 @@ var (
 	grayscale     bool
 	negative      bool
 	colored       bool
+	colorBg       bool
 	customMap     string
 	flipX         bool
 	flipY         bool
 	full          bool
 	fontPath      string
 	fontColor     [3]int
-	saveBgColor   [3]int
+	saveBgColor   [4]int
+	braille       bool
+	threshold     int
+	dither        bool
+	onlySave      bool
+	inputIsGif    bool
 )

aic_package/winsize/winsize_unix.go

@@ -1,4 +1,5 @@
-// +build unix, !windows
+//go:build (unix && ignore) || !windows
+// +build unix,ignore !windows
 
 package winsize
 

aic_package/winsize/winsize_windows.go

@@ -1,4 +1,5 @@
-// +build windows, !unix
+//go:build (windows && ignore) || !unix
+// +build windows,ignore !unix
 
 package winsize
 

cmd/root.go

@@ -40,6 +40,7 @@ var (
 	negative      bool
 	formatsTrue   bool
 	colored       bool
+	colorBg       bool
 	grayscale     bool
 	customMap     string
 	flipX         bool
@@ -48,12 +49,16 @@ var (
 	fontFile      string
 	fontColor     []int
 	saveBgColor   []int
+	braille       bool
+	threshold     int
+	dither        bool
+	onlySave      bool
 
 	// Root commands
 	rootCmd = &cobra.Command{
-		Use:     "ascii-image-converter [image paths/urls]",
+		Use:     "ascii-image-converter [image paths/urls or piped stdin]",
 		Short:   "Converts images and gifs into ascii art",
-		Version: "1.6.0",
+		Version: "1.13.1",
 		Long:    "This tool converts images into ascii art and prints them on the terminal.\nFurther configuration can be managed with flags.",
 
 		// Not RunE since help text is getting larger and seeing it for every error impacts user experience
@@ -73,6 +78,7 @@ var (
 				SaveGifPath:         saveGifPath,
 				Negative:            negative,
 				Colored:             colored,
+				CharBackgroundColor: colorBg,
 				Grayscale:           grayscale,
 				CustomMap:           customMap,
 				FlipX:               flipX,
@@ -80,29 +86,47 @@ var (
 				Full:                full,
 				FontFilePath:        fontFile,
 				FontColor:           [3]int{fontColor[0], fontColor[1], fontColor[2]},
-				SaveBackgroundColor: [3]int{saveBgColor[0], saveBgColor[1], saveBgColor[2]},
+				SaveBackgroundColor: [4]int{saveBgColor[0], saveBgColor[1], saveBgColor[2], saveBgColor[3]},
+				Braille:             braille,
+				Threshold:           threshold,
+				Dither:              dither,
+				OnlySave:            onlySave,
+			}
+
+			if args[0] == "-" {
+				printAscii(args[0], flags)
+				return
 			}
 
 			for _, imagePath := range args {
-
+				if err := printAscii(imagePath, flags); err != nil {
-				if asciiArt, err := aic_package.Convert(imagePath, flags); err == nil {
+					return
-					fmt.Printf("%s", asciiArt)
-				} else {
-					fmt.Printf("Error: %v\n", err)
-
-					// Because this error will then be thrown for every image path/url passed
-					// if save path is invalid
-					if err.Error()[:15] == "can't save file" {
-						fmt.Println()
-						return
-					}
 				}
-				fmt.Println()
 			}
 		},
 	}
 )
 
+func printAscii(imagePath string, flags aic_package.Flags) error {
+
+	if asciiArt, err := aic_package.Convert(imagePath, flags); err == nil {
+		fmt.Printf("%s", asciiArt)
+	} else {
+		fmt.Printf("Error: %v\n", err)
+
+		// Because this error will then be thrown for every image path/url passed
+		// if save path is invalid
+		if err.Error()[:15] == "can't save file" {
+			fmt.Println()
+			return err
+		}
+	}
+	if !onlySave {
+		fmt.Println()
+	}
+	return nil
+}
+
 // Cobra configuration from here on
 
 func Execute() {
@@ -119,12 +143,16 @@ func init() {
 	rootCmd.Flags().SortFlags = false
 
 	// rootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.ascii-image-converter.yaml)")
-	rootCmd.PersistentFlags().BoolVarP(&colored, "color", "C", false, "Display ascii art with original colors\n(Can work with the --negative flag)\n(Overrides --grayscale and --font-color flags)\n")
+	rootCmd.PersistentFlags().BoolVarP(&colored, "color", "C", false, "Display ascii art with original colors\nIf 24-bit colors aren't supported, uses 8-bit\n(Inverts with --negative flag)\n(Overrides --grayscale and --font-color flags)\n")
+	rootCmd.PersistentFlags().BoolVar(&colorBg, "color-bg", false, "If some color flag is passed, use that color\non character background instead of foreground\n(Inverts with --negative flag)\n(Only applicable for terminal display)\n")
 	rootCmd.PersistentFlags().IntSliceVarP(&dimensions, "dimensions", "d", nil, "Set width and height for ascii art in CHARACTER length\ne.g. -d 60,30 (defaults to terminal height)\n(Overrides --width and --height flags)\n")
 	rootCmd.PersistentFlags().IntVarP(&width, "width", "W", 0, "Set width for ascii art in CHARACTER length\nHeight is kept to aspect ratio\ne.g. -W 60\n")
 	rootCmd.PersistentFlags().IntVarP(&height, "height", "H", 0, "Set height for ascii art in CHARACTER length\nWidth is kept to aspect ratio\ne.g. -H 60\n")
 	rootCmd.PersistentFlags().StringVarP(&customMap, "map", "m", "", "Give custom ascii characters to map against\nOrdered from darkest to lightest\ne.g. -m \" .-+#@\" (Quotation marks excluded from map)\n(Overrides --complex flag)\n")
-	rootCmd.PersistentFlags().BoolVarP(&grayscale, "grayscale", "g", false, "Display grayscale ascii art\n(Can work with --negative flag)\n(Overrides --font-color flag)\n")
+	rootCmd.PersistentFlags().BoolVarP(&braille, "braille", "b", false, "Use braille characters instead of ascii\nTerminal must support braille patterns properly\n(Overrides --complex and --map flags)\n")
+	rootCmd.PersistentFlags().IntVar(&threshold, "threshold", 0, "Threshold for braille art\nValue between 0-255 is accepted\ne.g. --threshold 170\n(Defaults to 128)\n")
+	rootCmd.PersistentFlags().BoolVar(&dither, "dither", false, "Apply dithering on image for braille\nart conversion\n(Only applicable with --braille flag)\n(Negates --threshold flag)\n")
+	rootCmd.PersistentFlags().BoolVarP(&grayscale, "grayscale", "g", false, "Display grayscale ascii art\n(Inverts with --negative flag)\n(Overrides --font-color flag)\n")
 	rootCmd.PersistentFlags().BoolVarP(&complex, "complex", "c", false, "Display ascii characters in a larger range\nMay result in higher quality\n")
 	rootCmd.PersistentFlags().BoolVarP(&full, "full", "f", false, "Use largest dimensions for ascii art\nthat fill the terminal width\n(Overrides --dimensions, --width and --height flags)\n")
 	rootCmd.PersistentFlags().BoolVarP(&negative, "negative", "n", false, "Display ascii art in negative colors\n")
@@ -133,14 +161,17 @@ func init() {
 	rootCmd.PersistentFlags().StringVarP(&saveImagePath, "save-img", "s", "", "Save ascii art as a .png file\nFormat: <image-name>-ascii-art.png\nImage will be saved in passed path\n(pass . for current directory)\n")
 	rootCmd.PersistentFlags().StringVar(&saveTxtPath, "save-txt", "", "Save ascii art as a .txt file\nFormat: <image-name>-ascii-art.txt\nFile will be saved in passed path\n(pass . for current directory)\n")
 	rootCmd.PersistentFlags().StringVar(&saveGifPath, "save-gif", "", "If input is a gif, save it as a .gif file\nFormat: <gif-name>-ascii-art.gif\nGif will be saved in passed path\n(pass . for current directory)\n")
-	rootCmd.PersistentFlags().IntSliceVar(&saveBgColor, "save-bg", nil, "Set background color for --save-img and --save-gif flags\nPass an RGB value\ne.g. --save-bg 255,255,255\n(Defaults to 0,0,0)\n")
+	rootCmd.PersistentFlags().IntSliceVar(&saveBgColor, "save-bg", nil, "Set background color for --save-img\nand --save-gif flags\nPass an RGBA value\ne.g. --save-bg 255,255,255,100\n(Defaults to 0,0,0,100)\n")
-	rootCmd.PersistentFlags().StringVar(&fontFile, "font", "", "Set font for --save-img and --save-gif flags\nPass file path to font .ttf file\ne.g. --font ./RobotoMono-Regular.ttf\n(Defaults to Hack-Regular)\n")
+	rootCmd.PersistentFlags().StringVar(&fontFile, "font", "", "Set font for --save-img and --save-gif flags\nPass file path to font .ttf file\ne.g. --font ./RobotoMono-Regular.ttf\n(Defaults to Hack-Regular for ascii and\n DejaVuSans-Oblique for braille)\n")
 	rootCmd.PersistentFlags().IntSliceVar(&fontColor, "font-color", nil, "Set font color for terminal as well as\n--save-img and --save-gif flags\nPass an RGB value\ne.g. --font-color 0,0,0\n(Defaults to 255,255,255)\n")
+	rootCmd.PersistentFlags().BoolVar(&onlySave, "only-save", false, "Don't print ascii art on terminal\nif some saving flag is passed\n")
 	rootCmd.PersistentFlags().BoolVar(&formatsTrue, "formats", false, "Display supported input formats\n")
 
 	rootCmd.PersistentFlags().BoolP("help", "h", false, "Help for "+rootCmd.Name()+"\n")
 	rootCmd.PersistentFlags().BoolP("version", "v", false, "Version for "+rootCmd.Name())
 
+	rootCmd.SetVersionTemplate("{{printf \"v%s\" .Version}}\n")
+
 	defaultUsageTemplate := rootCmd.UsageTemplate()
 	rootCmd.SetUsageTemplate(defaultUsageTemplate + "\nCopyright © 2021 Zoraiz Hassan <hzoraiz8@gmail.com>\n" +
 		"Distributed under the Apache License Version 2.0 (Apache-2.0)\n" +

cmd/util.go

@@ -19,8 +19,6 @@ package cmd
 import (
 	"fmt"
 	"path"
-
-	"github.com/TheZoraiz/ascii-image-converter/aic_package/winsize"
 )
 
 // Check input and flag values for detecting errors or invalid inputs
@@ -29,6 +27,8 @@ func checkInputAndFlags(args []string) bool {
 	gifCount := 0
 	gifPresent := false
 	nonGifPresent := false
+	pipeCharPresent := false
+
 	for _, arg := range args {
 		extension := path.Ext(arg)
 
@@ -38,14 +38,18 @@ func checkInputAndFlags(args []string) bool {
 		} else {
 			nonGifPresent = true
 		}
+
+		if arg == "-" {
+			pipeCharPresent = true
+		}
 	}
 
-	if gifPresent && nonGifPresent {
+	if gifPresent && nonGifPresent && !onlySave {
 		fmt.Printf("Error: There are other inputs along with GIFs\nDue to the potential looping nature of GIFs, non-GIFs must not be supplied alongside\n\n")
 		return true
 	}
 
-	if gifCount > 1 {
+	if gifCount > 1 && !onlySave {
 		fmt.Printf("Error: There are multiple GIFs supplied\nDue to the potential looping nature of GIFs, only one GIF per command is supported\n\n")
 		return true
 	}
@@ -57,12 +61,17 @@ func checkInputAndFlags(args []string) bool {
 			"WEBP\n" +
 			"BMP\n" +
 			"TIFF/TIF\n" +
-			"GIF (Experimental)\n\n")
+			"GIF\n\n")
 		return true
 	}
 
 	if len(args) < 1 {
-		fmt.Printf("Error: Need at least 1 input path/url\nUse the -h flag for more info\n\n")
+		fmt.Printf("Error: Need at least 1 input path/url or piped input\nUse the -h flag for more info\n\n")
+		return true
+	}
+
+	if len(args) > 1 && pipeCharPresent {
+		fmt.Printf("Error: You cannot pass in piped input alongside other inputs\n\n")
 		return true
 	}
 
@@ -83,18 +92,6 @@ func checkInputAndFlags(args []string) bool {
 			fmt.Printf("Error: invalid values for dimensions\n\n")
 			return true
 		}
-
-		defaultTermWidth, _, err := winsize.GetTerminalSize()
-		if err != nil {
-			fmt.Printf("Error: %v\n\n", err)
-			return true
-		}
-
-		defaultTermWidth -= 1
-		if dimensions[0] > defaultTermWidth {
-			fmt.Printf("Error: set width must be lower than terminal width\n\n")
-			return true
-		}
 	}
 
 	if width != 0 || height != 0 {
@@ -102,21 +99,9 @@ func checkInputAndFlags(args []string) bool {
 		if width != 0 && height != 0 {
 			fmt.Printf("Error: both --width and --height can't be set. Use --dimensions instead\n\n")
 			return true
+
 		} else {
 
-			defaultTermWidth, _, err := winsize.GetTerminalSize()
-			if err != nil {
-				fmt.Printf("Error: %v\n\n", err)
-				return true
-			}
-
-			// Check if set width exceeds terminal
-			defaultTermWidth -= 1
-			if width > defaultTermWidth {
-				fmt.Printf("Error: set width must be lower than terminal width\n\n")
-				return true
-			}
-
 			if width < 0 {
 				fmt.Printf("Error: invalid value for width\n\n")
 				return true
@@ -132,21 +117,23 @@ func checkInputAndFlags(args []string) bool {
 	}
 
 	if saveBgColor == nil {
-		saveBgColor = []int{0, 0, 0}
+		saveBgColor = []int{0, 0, 0, 100}
 	} else {
 		bgValues := len(saveBgColor)
-		if bgValues != 3 {
+		if bgValues != 4 {
-			fmt.Printf("Error: --save-bg requires 3 values for RGB, got %v\n\n", bgValues)
+			fmt.Printf("Error: --save-bg requires 4 values for RGBA, got %v\n\n", bgValues)
 			return true
 		}
 
-		if saveBgColor[0] < 0 || saveBgColor[1] < 0 || saveBgColor[2] < 0 {
+		if saveBgColor[0] < 0 || saveBgColor[1] < 0 || saveBgColor[2] < 0 || saveBgColor[3] < 0 {
-			fmt.Printf("Error: RBG values must be between 0 and 255\n\n")
+			fmt.Printf("Error: RBG values must be between 0 and 255\n")
+			fmt.Printf("Error: Opacity value must be between 0 and 100\n\n")
 			return true
 		}
 
-		if saveBgColor[0] > 255 || saveBgColor[1] > 255 || saveBgColor[2] > 255 {
+		if saveBgColor[0] > 255 || saveBgColor[1] > 255 || saveBgColor[2] > 255 || saveBgColor[3] > 100 {
-			fmt.Printf("Error: RBG values must be between 0 and 255\n\n")
+			fmt.Printf("Error: RBG values must be between 0 and 255\n")
+			fmt.Printf("Error: Opacity value must be between 0 and 100\n\n")
 			return true
 		}
 	}
@@ -171,5 +158,24 @@ func checkInputAndFlags(args []string) bool {
 		}
 	}
 
+	if threshold == 0 {
+		threshold = 128
+	}
+
+	if threshold < 0 || threshold > 255 {
+		fmt.Printf("Error: threshold must be between 0 and 255\n\n")
+		return true
+	}
+
+	if dither && !braille {
+		fmt.Printf("Error: image dithering is only reserved for --braille flag\n\n")
+		return true
+	}
+
+	if (saveTxtPath == "" && saveImagePath == "" && saveGifPath == "") && onlySave {
+		fmt.Printf("Error: you need to supply one of --save-img, --save-txt or --save-gif for using --only-save\n\n")
+		return true
+	}
+
 	return false
 }

go.mod

@@ -1,26 +1,35 @@
 module github.com/TheZoraiz/ascii-image-converter
 
-go 1.16
+go 1.17
 
 require (
-	github.com/asaskevich/govalidator v0.0.0-20210307081110-f21760c49a8d
+	github.com/disintegration/imaging v1.6.2
 	github.com/fogleman/gg v1.3.0
-	github.com/fsnotify/fsnotify v1.4.9 // indirect
 	github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0
 	github.com/gookit/color v1.4.2
-	github.com/magiconair/properties v1.8.5 // indirect
+	github.com/makeworld-the-better-one/dither/v2 v2.2.0
 	github.com/mitchellh/go-homedir v1.1.0
-	github.com/mitchellh/mapstructure v1.4.1 // indirect
 	github.com/nathan-fiscaletti/consolesize-go v0.0.0-20210105204122-a87d9f614b9d
-	github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646
+	github.com/spf13/cobra v1.1.3
+	github.com/spf13/viper v1.7.1
+	golang.org/x/image v0.0.0-20210628002857-a66eb6448b8d
+)
+
+require (
+	github.com/fsnotify/fsnotify v1.4.9 // indirect
+	github.com/hashicorp/hcl v1.0.0 // indirect
+	github.com/inconshreveable/mousetrap v1.0.0 // indirect
+	github.com/magiconair/properties v1.8.5 // indirect
+	github.com/mitchellh/mapstructure v1.4.1 // indirect
 	github.com/pelletier/go-toml v1.9.1 // indirect
 	github.com/spf13/afero v1.6.0 // indirect
 	github.com/spf13/cast v1.3.1 // indirect
-	github.com/spf13/cobra v1.1.3
 	github.com/spf13/jwalterweatherman v1.1.0 // indirect
-	github.com/spf13/viper v1.7.1
+	github.com/spf13/pflag v1.0.5 // indirect
-	golang.org/x/image v0.0.0-20210504121937-7319ad40d33e
+	github.com/subosito/gotenv v1.2.0 // indirect
+	github.com/xo/terminfo v0.0.0-20210125001918-ca9a967f8778 // indirect
 	golang.org/x/sys v0.0.0-20210601080250-7ecdf8ef093b // indirect
 	golang.org/x/text v0.3.6 // indirect
 	gopkg.in/ini.v1 v1.62.0 // indirect
+	gopkg.in/yaml.v2 v2.4.0 // indirect
 )

go.sum

@@ -19,8 +19,6 @@ github.com/alecthomas/units v0.0.0-20151022065526-2efee857e7cf/go.mod h1:ybxpYRF
 github.com/armon/circbuf v0.0.0-20150827004946-bbbad097214e/go.mod h1:3U/XgcO3hCbHZ8TKRvWD2dDTCfh9M9ya+I9JpbB7O8o=
 github.com/armon/go-metrics v0.0.0-20180917152333-f0300d1749da/go.mod h1:Q73ZrmVTwzkszR9V5SSuryQ31EELlFMUz1kKyl939pY=
 github.com/armon/go-radix v0.0.0-20180808171621-7fddfc383310/go.mod h1:ufUuZ+zHj4x4TnLV4JWEpy2hxWSpsRywHrMgIH9cCH8=
-github.com/asaskevich/govalidator v0.0.0-20210307081110-f21760c49a8d h1:Byv0BzEl3/e6D5CLfI0j/7hiIEtvGVFPCZ7Ei2oq8iQ=
-github.com/asaskevich/govalidator v0.0.0-20210307081110-f21760c49a8d/go.mod h1:WaHUgvxTVq04UNunO+XhnAqY/wQc+bxr74GqbsZ/Jqw=
 github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973/go.mod h1:Dwedo/Wpr24TaqPxmxbtue+5NUziq4I4S80YR8gNf3Q=
 github.com/beorn7/perks v1.0.0/go.mod h1:KWe93zE9D1o94FZ5RNwFwVgaQK1VOXiVxmqh+CedLV8=
 github.com/bgentry/speakeasy v0.1.0/go.mod h1:+zsyZBPWlz7T6j88CTgSN5bM796AkVf0kBD4zp0CCIs=
@@ -38,6 +36,8 @@ github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/dgrijalva/jwt-go v3.2.0+incompatible/go.mod h1:E3ru+11k8xSBh+hMPgOLZmtrrCbhqsmaPHjLKYnJCaQ=
 github.com/dgryski/go-sip13 v0.0.0-20181026042036-e10d5fee7954/go.mod h1:vAd38F8PWV+bWy6jNmig1y/TA+kYO4g3RSRF0IAv0no=
+github.com/disintegration/imaging v1.6.2 h1:w1LecBlG2Lnp8B3jk5zSuNqd7b4DXhcjwek1ei82L+c=
+github.com/disintegration/imaging v1.6.2/go.mod h1:44/5580QXChDfwIclfc/PCwrr44amcmDAg8hxG0Ewe4=
 github.com/fatih/color v1.7.0/go.mod h1:Zm6kSWBoL9eyXnKyktHP6abPY2pDugNf5KwzbycvMj4=
 github.com/fogleman/gg v1.3.0 h1:/7zJX8F6AaYQc57WQCyN9cAIz+4bCJGO9B+dyW29am8=
 github.com/fogleman/gg v1.3.0/go.mod h1:R/bRT+9gY/C5z7JzPU0zXsXHKM4/ayA+zqcVNZzPa1k=
@@ -122,6 +122,8 @@ github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/magiconair/properties v1.8.1/go.mod h1:PppfXfuXeibc/6YijjN8zIbojt8czPbwD3XqdrwzmxQ=
 github.com/magiconair/properties v1.8.5 h1:b6kJs+EmPFMYGkow9GiUyCyOvIwYetYJ3fSaWak/Gls=
 github.com/magiconair/properties v1.8.5/go.mod h1:y3VJvCyxH9uVvJTWEGAELF3aiYNyPKd5NZ3oSwXrF60=
+github.com/makeworld-the-better-one/dither/v2 v2.2.0 h1:VTMAiyyO1YIO07fZwuLNZZasJgKUmvsIA48ze3ALHPQ=
+github.com/makeworld-the-better-one/dither/v2 v2.2.0/go.mod h1:VBtN8DXO7SNtyGmLiGA7IsFeKrBkQPze1/iAeM95arc=
 github.com/mattn/go-colorable v0.0.9/go.mod h1:9vuHe8Xs5qXnSaW/c/ABM9alt+Vo+STaOChaDxuIBZU=
 github.com/mattn/go-isatty v0.0.3/go.mod h1:M+lRXTBqGeGNdLjl/ufCoiOlB5xdOkqRJdNxMWT7Zi4=
 github.com/matttproud/golang_protobuf_extensions v1.0.1/go.mod h1:D8He9yQNgCq6Z5Ld7szi9bcBfOoFv/3dc6xSMkL2PC0=
@@ -142,8 +144,6 @@ github.com/modern-go/reflect2 v1.0.1/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3Rllmb
 github.com/mwitkow/go-conntrack v0.0.0-20161129095857-cc309e4a2223/go.mod h1:qRWi+5nqEBWmkhHvq77mSJWrCKwh8bxhgT7d/eI7P4U=
 github.com/nathan-fiscaletti/consolesize-go v0.0.0-20210105204122-a87d9f614b9d h1:PQW4Aqovdqc9efHl9EVA+bhKmuZ4ME1HvSYYDvaDiK0=
 github.com/nathan-fiscaletti/consolesize-go v0.0.0-20210105204122-a87d9f614b9d/go.mod h1:cxIIfNMTwff8f/ZvRouvWYF6wOoO7nj99neWSx2q/Es=
-github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646 h1:zYyBkD/k9seD2A7fsi6Oo2LfFZAehjjQMERAvZLEDnQ=
-github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646/go.mod h1:jpp1/29i3P1S/RLdc7JQKbRpFeM1dOBd8T9ki5s+AY8=
 github.com/oklog/ulid v1.3.1/go.mod h1:CirwcVhetQ6Lv90oh/F+FBtV6XMibvdAFo93nm5qn4U=
 github.com/pascaldekloe/goe v0.0.0-20180627143212-57f6aae5913c/go.mod h1:lzWF7FIEvWOWxwDKqyGYQf6ZUaNfKdP144TG7ZOy1lc=
 github.com/pelletier/go-toml v1.2.0/go.mod h1:5z9KED0ma1S8pY6P1sdut58dfprrGBbd/94hg7ilaic=
@@ -226,8 +226,9 @@ golang.org/x/exp v0.0.0-20190829153037-c13cbed26979/go.mod h1:86+5VVa7VpoJ4kLfm0
 golang.org/x/exp v0.0.0-20191030013958-a1ab85dbe136/go.mod h1:JXzH8nQsPlswgeRAPE3MuO9GYsAcnJvJ4vnMwN/5qkY=
 golang.org/x/image v0.0.0-20190227222117-0694c2d4d067/go.mod h1:kZ7UVZpmo3dzQBMxlp+ypCbDeSB+sBbTgSJuh5dn5js=
 golang.org/x/image v0.0.0-20190802002840-cff245a6509b/go.mod h1:FeLwcggjj3mMvU+oOTbSwawSJRM1uh48EjtB4UJZlP0=
-golang.org/x/image v0.0.0-20210504121937-7319ad40d33e h1:PzJMNfFQx+QO9hrC1GwZ4BoPGeNGhfeQEgcQFArEjPk=
+golang.org/x/image v0.0.0-20191009234506-e7c1f5e7dbb8/go.mod h1:FeLwcggjj3mMvU+oOTbSwawSJRM1uh48EjtB4UJZlP0=
-golang.org/x/image v0.0.0-20210504121937-7319ad40d33e/go.mod h1:FeLwcggjj3mMvU+oOTbSwawSJRM1uh48EjtB4UJZlP0=
+golang.org/x/image v0.0.0-20210628002857-a66eb6448b8d h1:RNPAfi2nHY7C2srAV8A49jpsYr0ADedCk1wq6fTMTvs=
+golang.org/x/image v0.0.0-20210628002857-a66eb6448b8d/go.mod h1:023OzeP/+EPmXeapQh35lcL3II3LrY8Ic+EFFKVhULM=
 golang.org/x/lint v0.0.0-20181026193005-c67002cb31c3/go.mod h1:UVdnD1Gm6xHRNCYTkRU2/jEulfH38KcIWyp/GAMgvoE=
 golang.org/x/lint v0.0.0-20190227174305-5b3e6a55c961/go.mod h1:wehouNa3lNwaWXcvxsM5YxQ5yQlVC4a0KAMCusXpPoU=
 golang.org/x/lint v0.0.0-20190301231843-5614ed5bae6f/go.mod h1:UVdnD1Gm6xHRNCYTkRU2/jEulfH38KcIWyp/GAMgvoE=

image_manipulation/ascii_conversions.go

@@ -16,101 +16,24 @@ limitations under the License.
 
 package image_conversions
 
-import (
+var (
-	"strconv"
+	// Reference taken from http://paulbourke.net/dataformats/asciiart/
+	asciiTableSimple   = " .:-=+*#%@"
+	asciiTableDetailed = " .'`^\",:;Il!i><~+_-?][}{1)(|\\/tfjrxnuvczXYUJCLQ0OZmwqpdbkhao*#MW&8%B@$"
 
-	"github.com/gookit/color"
+	// Structure for braille dots
+	BrailleStruct = [4][2]int{
+		{0x1, 0x8},
+		{0x2, 0x10},
+		{0x4, 0x20},
+		{0x40, 0x80},
+	}
+
+	BrailleThreshold uint32
 )
 
-// Reference taken from http://paulbourke.net/dataformats/asciiart/
-var asciiTableSimple = map[int]string{
-	0: " ",
-	1: ".",
-	2: ":",
-	3: "-",
-	4: "=",
-	5: "+",
-	6: "*",
-	7: "#",
-	8: "%",
-	9: "@",
-}
-
-// Reference taken from http://paulbourke.net/dataformats/asciiart/
-var asciiTableDetailed = map[int]string{
-	0:  " ",
-	1:  ".",
-	2:  "'",
-	3:  "`",
-	4:  "^",
-	5:  "\"",
-	6:  ",",
-	7:  ":",
-	8:  ";",
-	9:  "I",
-	10: "l",
-	11: "!",
-	12: "i",
-	13: ">",
-	14: "<",
-	15: "~",
-	16: "+",
-	17: "_",
-	18: "-",
-	19: "?",
-	20: "]",
-	21: "[",
-	22: "}",
-	23: "{",
-	24: "1",
-	25: ")",
-	26: "(",
-	27: "|",
-	28: "/",
-	29: "t",
-	30: "f",
-	31: "j",
-	32: "r",
-	33: "x",
-	34: "n",
-	35: "u",
-	36: "v",
-	37: "c",
-	38: "z",
-	39: "X",
-	40: "Y",
-	41: "U",
-	42: "J",
-	43: "C",
-	44: "L",
-	45: "Q",
-	46: "0",
-	47: "O",
-	48: "Z",
-	49: "m",
-	50: "w",
-	51: "q",
-	52: "p",
-	53: "d",
-	54: "b",
-	55: "k",
-	56: "h",
-	57: "a",
-	58: "o",
-	59: "*",
-	60: "#",
-	61: "M",
-	62: "W",
-	63: "&",
-	64: "8",
-	65: "%",
-	66: "B",
-	67: "@",
-	68: "$",
-}
-
 // For each individual element of imgSet in ConvertToASCIISlice()
-const MAX_VAL float64 = 65535
+const MAX_VAL float64 = 255
 
 type AsciiChar struct {
 	OriginalColor string
@@ -119,24 +42,34 @@ type AsciiChar struct {
 	RgbValue      [3]uint32
 }
 
-// Converts the 2D image_conversions.AsciiPixel slice of image data (each instance representing each compressed pixel of original image)
+/*
-// to a 2D image_conversions.AsciiChar slice
+Converts the 2D image_conversions.AsciiPixel slice of image data (each instance representing each compressed pixel of original image)
-//
+to a 2D image_conversions.AsciiChar slice
-// If complex parameter is true, values are compared to 69 levels of color density in ASCII characters.
+
-// Otherwise, values are compared to 10 levels of color density in ASCII characters.
+If complex parameter is true, values are compared to 70 levels of color density in ASCII characters.
-func ConvertToAsciiChars(imgSet [][]AsciiPixel, negative, colored, complex bool, customMap string, fontColor [3]int) [][]AsciiChar {
+Otherwise, values are compared to 10 levels of color density in ASCII characters.
+*/
+func ConvertToAsciiChars(imgSet [][]AsciiPixel, negative, colored, grayscale, complex, colorBg bool, customMap string, fontColor [3]int) ([][]AsciiChar, error) {
 
 	height := len(imgSet)
 	width := len(imgSet[0])
 
-	var chosenTable map[int]string
+	chosenTable := map[int]string{}
 
+	// Turn ascii character-set string into map[int]string{} literal
 	if customMap == "" {
+		var charSet string
+
 		if complex {
-			chosenTable = asciiTableDetailed
+			charSet = asciiTableDetailed
 		} else {
-			chosenTable = asciiTableSimple
+			charSet = asciiTableSimple
 		}
+
+		for index, char := range charSet {
+			chosenTable[index] = string(char)
+		}
+
 	} else {
 		chosenTable = map[int]string{}
 
@@ -145,10 +78,7 @@ func ConvertToAsciiChars(imgSet [][]AsciiPixel, negative, colored, complex bool,
 		}
 	}
 
-	result := make([][]AsciiChar, height)
+	var result [][]AsciiChar
-	for i := range result {
-		result[i] = make([]AsciiChar, width)
-	}
 
 	for i := 0; i < height; i++ {
 
@@ -192,25 +122,37 @@ func ConvertToAsciiChars(imgSet [][]AsciiPixel, negative, colored, complex bool,
 				tempInt = (len(chosenTable) - 1) - tempInt
 			}
 
-			rStr := strconv.Itoa(r)
-			gStr := strconv.Itoa(g)
-			bStr := strconv.Itoa(b)
-
 			var char AsciiChar
 
-			char.OriginalColor = color.Sprintf("<fg="+rStr+","+gStr+","+bStr+">%v</>", chosenTable[tempInt])
+			asciiChar := chosenTable[tempInt]
+			char.Simple = asciiChar
+
+			var err error
+			if colorBg {
+				char.OriginalColor, err = getColoredCharForTerm(uint8(r), uint8(g), uint8(b), asciiChar, true)
+			} else {
+				char.OriginalColor, err = getColoredCharForTerm(uint8(r), uint8(g), uint8(b), asciiChar, false)
+			}
+			if (colored || grayscale) && err != nil {
+				return nil, err
+			}
 
 			// If font color is not set, use a simple string. Otherwise, use True color
 			if fontColor != [3]int{255, 255, 255} {
-				fcR := strconv.Itoa(fontColor[0])
+				fcR := fontColor[0]
-				fcG := strconv.Itoa(fontColor[1])
+				fcG := fontColor[1]
-				fcB := strconv.Itoa(fontColor[2])
+				fcB := fontColor[2]
 
-				char.SetColor = color.Sprintf("<fg="+fcR+","+fcG+","+fcB+">%v</>", chosenTable[tempInt])
+				if colorBg {
+					char.SetColor, err = getColoredCharForTerm(uint8(fcR), uint8(fcG), uint8(fcB), asciiChar, true)
+				} else {
+					char.SetColor, err = getColoredCharForTerm(uint8(fcR), uint8(fcG), uint8(fcB), asciiChar, false)
+				}
+				if err != nil {
+					return nil, err
+				}
 			}
 
-			char.Simple = chosenTable[tempInt]
-
 			if colored {
 				char.RgbValue = imgSet[i][j].rgbValue
 			} else {
@@ -219,8 +161,123 @@ func ConvertToAsciiChars(imgSet [][]AsciiPixel, negative, colored, complex bool,
 
 			tempSlice = append(tempSlice, char)
 		}
-		result[i] = tempSlice
+		result = append(result, tempSlice)
 	}
 
-	return result
+	return result, nil
+}
+
+/*
+Converts the 2D image_conversions.AsciiPixel slice of image data (each instance representing each compressed pixel of original image)
+to a 2D image_conversions.AsciiChar slice
+
+Unlike ConvertToAsciiChars(), this function calculates braille characters instead of ascii
+*/
+func ConvertToBrailleChars(imgSet [][]AsciiPixel, negative, colored, grayscale, colorBg bool, fontColor [3]int, threshold int) ([][]AsciiChar, error) {
+
+	BrailleThreshold = uint32(threshold)
+
+	height := len(imgSet)
+	width := len(imgSet[0])
+
+	var result [][]AsciiChar
+
+	for i := 0; i < height; i += 4 {
+
+		var tempSlice []AsciiChar
+
+		for j := 0; j < width; j += 2 {
+
+			brailleChar := getBrailleChar(i, j, negative, imgSet)
+
+			var r, g, b int
+
+			if colored {
+				r = int(imgSet[i][j].rgbValue[0])
+				g = int(imgSet[i][j].rgbValue[1])
+				b = int(imgSet[i][j].rgbValue[2])
+			} else {
+				r = int(imgSet[i][j].grayscaleValue[0])
+				g = int(imgSet[i][j].grayscaleValue[1])
+				b = int(imgSet[i][j].grayscaleValue[2])
+			}
+
+			if negative {
+				// Select character from opposite side of table as well as turn pixels negative
+				r = 255 - r
+				g = 255 - g
+				b = 255 - b
+
+				if colored {
+					imgSet[i][j].rgbValue = [3]uint32{uint32(r), uint32(g), uint32(b)}
+				} else {
+					imgSet[i][j].grayscaleValue = [3]uint32{uint32(r), uint32(g), uint32(b)}
+				}
+			}
+
+			var char AsciiChar
+
+			char.Simple = brailleChar
+
+			var err error
+			if colorBg {
+				char.OriginalColor, err = getColoredCharForTerm(uint8(r), uint8(g), uint8(b), brailleChar, true)
+			} else {
+				char.OriginalColor, err = getColoredCharForTerm(uint8(r), uint8(g), uint8(b), brailleChar, false)
+			}
+			if (colored || grayscale) && err != nil {
+				return nil, err
+			}
+
+			// If font color is not set, use a simple string. Otherwise, use True color
+			if fontColor != [3]int{255, 255, 255} {
+				fcR := fontColor[0]
+				fcG := fontColor[1]
+				fcB := fontColor[2]
+
+				if colorBg {
+					char.SetColor, err = getColoredCharForTerm(uint8(fcR), uint8(fcG), uint8(fcB), brailleChar, true)
+				} else {
+					char.SetColor, err = getColoredCharForTerm(uint8(fcR), uint8(fcG), uint8(fcB), brailleChar, false)
+				}
+				if err != nil {
+					return nil, err
+				}
+			}
+
+			if colored {
+				char.RgbValue = imgSet[i][j].rgbValue
+			} else {
+				char.RgbValue = imgSet[i][j].grayscaleValue
+			}
+
+			tempSlice = append(tempSlice, char)
+		}
+
+		result = append(result, tempSlice)
+	}
+
+	return result, nil
+}
+
+// Iterate through the BrailleStruct table to see which dots need to be highlighted
+func getBrailleChar(x, y int, negative bool, imgSet [][]AsciiPixel) string {
+
+	brailleChar := 0x2800
+
+	for i := 0; i < 4; i++ {
+		for j := 0; j < 2; j++ {
+			if negative {
+				if imgSet[x+i][y+j].charDepth <= BrailleThreshold {
+					brailleChar += BrailleStruct[i][j]
+				}
+			} else {
+				if imgSet[x+i][y+j].charDepth >= BrailleThreshold {
+					brailleChar += BrailleStruct[i][j]
+				}
+			}
+		}
+	}
+
+	return string(brailleChar)
 }

image_manipulation/image_conversions.go

@@ -17,12 +17,8 @@ limitations under the License.
 package image_conversions
 
 import (
-	"fmt"
 	"image"
 	"image/color"
-
-	"github.com/TheZoraiz/ascii-image-converter/aic_package/winsize"
-	"github.com/nfnt/resize"
 )
 
 type AsciiPixel struct {
@@ -31,121 +27,30 @@ type AsciiPixel struct {
 	rgbValue       [3]uint32
 }
 
-// This function shrinks the passed image according to passed dimensions or terminal
+/*
-// size if none are passed. Stores each pixel's grayscale and RGB values in an AsciiPixel
+This function shrinks the passed image according to specified or default dimensions.
-// instance to simplify getting numeric data for ASCII character comparison.
+Stores each pixel's grayscale and RGB values in an AsciiPixel instance to simplify
-//
+getting numeric data for ASCII character comparison.
-// The returned 2D AsciiPixel slice contains each corresponding pixel's values. Grayscale value
-// ranges from 0 to 65535, while RGB values are separate.
-func ConvertToAsciiPixels(img image.Image, dimensions []int, width, height int, flipX, flipY, full bool) ([][]AsciiPixel, error) {
 
-	var asciiWidth, asciiHeight int
+The returned 2D AsciiPixel slice contains each corresponding pixel's values
-	var smallImg image.Image
+*/
+func ConvertToAsciiPixels(img image.Image, dimensions []int, width, height int, flipX, flipY, full, isBraille, dither bool) ([][]AsciiPixel, error) {
+
+	smallImg, err := resizeImage(img, full, isBraille, dimensions, width, height)
 
-	terminalWidth, terminalHeight, err := winsize.GetTerminalSize()
 	if err != nil {
 		return nil, err
 	}
 
-	if full {
+	// We mainatin a dithered image literal along with original image
-		asciiWidth = terminalWidth - 1
+	// The colors are kept from original image
+	var ditheredImage image.Image
 
-		// Passing 0 in place of width keeps the original image's aspect ratio
+	if isBraille && dither {
-		smallImg = resize.Resize(uint(asciiWidth), 0, img, resize.Lanczos3)
+		ditheredImage = ditherImage(smallImg)
-		asciiHeight = smallImg.Bounds().Max.Y - smallImg.Bounds().Min.Y
-
-		// To fix aspect ratio in eventual ascii art
-		asciiHeight = int(0.5 * float32(asciiHeight))
-
-		smallImg = resize.Resize(uint(asciiWidth), uint(asciiHeight), img, resize.Lanczos3)
-
-	} else if (width != 0 || height != 0) && len(dimensions) == 0 {
-		// If either width or height is set and dimensions aren't given
-
-		if width > terminalWidth-1 {
-			return nil, fmt.Errorf("set width must be lower than terminal width")
-		}
-
-		if width != 0 && height == 0 {
-			// If width is set and height is not set, use width to calculate aspect ratio
-
-			asciiWidth = width
-
-			smallImg = resize.Resize(uint(asciiWidth), 0, img, resize.Lanczos3)
-			asciiHeight = smallImg.Bounds().Max.Y - smallImg.Bounds().Min.Y
-
-			asciiHeight = int(0.5 * float32(asciiHeight))
-			if asciiHeight == 0 {
-				asciiHeight = 1
-			}
-
-			smallImg = resize.Resize(uint(asciiWidth), uint(asciiHeight), img, resize.Lanczos3)
-
-		} else if height != 0 && width == 0 {
-			// If height is set and width is not set, use height to calculate aspect ratio
-
-			asciiHeight = height
-
-			smallImg = resize.Resize(0, uint(asciiHeight), img, resize.Lanczos3)
-			asciiWidth = smallImg.Bounds().Max.X - smallImg.Bounds().Min.X
-
-			asciiWidth = int(2 * float32(asciiWidth))
-
-			if asciiWidth > terminalWidth-1 {
-				return nil, fmt.Errorf("width calculated with aspect ratio exceeds terminal width")
-			}
-
-			smallImg = resize.Resize(uint(asciiWidth), uint(asciiHeight), img, resize.Lanczos3)
-
-		} else {
-			return nil, fmt.Errorf("both width and height can't be set. Use dimensions instead")
-		}
-
-	} else if len(dimensions) == 0 {
-		// This condition calculates aspect ratio according to terminal height
-
-		asciiHeight = terminalHeight - 1
-
-		smallImg = resize.Resize(0, uint(asciiHeight), img, resize.Lanczos3)
-		asciiWidth = smallImg.Bounds().Max.X - smallImg.Bounds().Min.X
-
-		// To fix aspect ratio in eventual ascii art
-		asciiWidth = int(2 * float32(asciiWidth))
-
-		// If ascii width exceeds terminal width, change ratio with respect to terminal width
-		if asciiWidth >= terminalWidth {
-			asciiWidth = terminalWidth - 1
-
-			smallImg = resize.Resize(uint(asciiWidth), 0, img, resize.Lanczos3)
-
-			asciiHeight = smallImg.Bounds().Max.Y - smallImg.Bounds().Min.Y
-
-			// To fix aspect ratio in eventual ascii art
-			asciiHeight = int(0.5 * float32(asciiHeight))
-		}
-
-		smallImg = resize.Resize(uint(asciiWidth), uint(asciiHeight), img, resize.Lanczos3)
-
-	} else {
-		asciiWidth = dimensions[0]
-		asciiHeight = dimensions[1]
-		smallImg = resize.Resize(uint(asciiWidth), uint(asciiHeight), img, resize.Lanczos3)
 	}
 
-	// Repeated despite being in cmd/root.go to maintain support for library
+	var imgSet [][]AsciiPixel
-	//
-	// If there are passed dimensions, check whether the width exceeds terminal width
-	if len(dimensions) > 0 && !full {
-		if dimensions[0] > terminalWidth-1 {
-			return nil, fmt.Errorf("set width must be lower than terminal width")
-		}
-	}
-
-	// Initialize imgSet 2D slice
-	imgSet := make([][]AsciiPixel, asciiHeight)
-	for i := range imgSet {
-		imgSet[i] = make([]AsciiPixel, asciiWidth)
-	}
 
 	b := smallImg.Bounds()
 
@@ -159,11 +64,24 @@ func ConvertToAsciiPixels(img image.Image, dimensions []int, width, height int,
 			grayPixel := color.GrayModel.Convert(oldPixel)
 
 			r1, g1, b1, _ := grayPixel.RGBA()
-			charDepth := r1 // Only Red is needed from RGB for charDepth in AsciiPixel since they have the same value for grayscale images
+			charDepth := r1 / 257 // Only Red is needed from RGB for charDepth in AsciiPixel since they have the same value for grayscale images
 			r1 = uint32(r1 / 257)
 			g1 = uint32(g1 / 257)
 			b1 = uint32(b1 / 257)
 
+			if isBraille && dither {
+
+				// Change charDepth if image dithering is applied
+				// 		Note that neither grayscale nor original color values are changed.
+				// 		Only charDepth is kept from dithered image. This is because a
+				// 		dithered image loses its colors so it's only used to check braille
+				// 		dots' visibility
+
+				ditheredGrayPixel := color.GrayModel.Convert(ditheredImage.At(x, y))
+				charDepth, _, _, _ = ditheredGrayPixel.RGBA()
+				charDepth = charDepth / 257
+			}
+
 			// Get co1ored RGB values of original pixel for rgbValue in AsciiPixel
 			r2, g2, b2, _ := oldPixel.RGBA()
 			r2 = uint32(r2 / 257)
@@ -177,7 +95,7 @@ func ConvertToAsciiPixels(img image.Image, dimensions []int, width, height int,
 			})
 
 		}
-		imgSet[y] = temp
+		imgSet = append(imgSet, temp)
 	}
 
 	// This rarely affects performance since the ascii art 2D slice size isn't that large
@@ -187,22 +105,3 @@ func ConvertToAsciiPixels(img image.Image, dimensions []int, width, height int,
 
 	return imgSet, nil
 }
-
-func reverse(imgSet [][]AsciiPixel, flipX, flipY bool) [][]AsciiPixel {
-
-	if flipX {
-		for _, row := range imgSet {
-			for i, j := 0, len(row)-1; i < j; i, j = i+1, j-1 {
-				row[i], row[j] = row[j], row[i]
-			}
-		}
-	}
-
-	if flipY {
-		for i, j := 0, len(imgSet)-1; i < j; i, j = i+1, j-1 {
-			imgSet[i], imgSet[j] = imgSet[j], imgSet[i]
-		}
-	}
-
-	return imgSet
-}

image_manipulation/util.go

@@ -0,0 +1,166 @@
+/*
+Copyright © 2021 Zoraiz Hassan <hzoraiz8@gmail.com>
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package image_conversions
+
+import (
+	"fmt"
+	"image"
+	"image/color"
+
+	"github.com/TheZoraiz/ascii-image-converter/aic_package/winsize"
+	"github.com/disintegration/imaging"
+	gookitColor "github.com/gookit/color"
+	"github.com/makeworld-the-better-one/dither/v2"
+)
+
+func ditherImage(img image.Image) image.Image {
+
+	palette := []color.Color{
+		color.Black,
+		color.White,
+	}
+
+	d := dither.NewDitherer(palette)
+	d.Matrix = dither.FloydSteinberg
+
+	return d.DitherCopy(img)
+}
+
+func resizeImage(img image.Image, full, isBraille bool, dimensions []int, width, height int) (image.Image, error) {
+
+	var asciiWidth, asciiHeight int
+	var smallImg image.Image
+
+	imgWidth := float64(img.Bounds().Dx())
+	imgHeight := float64(img.Bounds().Dy())
+	aspectRatio := imgWidth / imgHeight
+
+	if full {
+		terminalWidth, _, err := winsize.GetTerminalSize()
+		if err != nil {
+			return nil, err
+		}
+
+		asciiWidth = terminalWidth - 1
+		asciiHeight = int(float64(asciiWidth) / aspectRatio)
+		asciiHeight = int(0.5 * float64(asciiHeight))
+
+	} else if (width != 0 || height != 0) && len(dimensions) == 0 {
+		// If either width or height is set and dimensions aren't given
+
+		if width != 0 && height == 0 {
+			// If width is set and height is not set, use width to calculate aspect ratio
+
+			asciiWidth = width
+			asciiHeight = int(float64(asciiWidth) / aspectRatio)
+			asciiHeight = int(0.5 * float64(asciiHeight))
+
+			if asciiHeight == 0 {
+				asciiHeight = 1
+			}
+
+		} else if height != 0 && width == 0 {
+			// If height is set and width is not set, use height to calculate aspect ratio
+
+			asciiHeight = height
+			asciiWidth = int(float64(asciiHeight) * aspectRatio)
+			asciiWidth = int(2 * float64(asciiWidth))
+
+			if asciiWidth == 0 {
+				asciiWidth = 1
+			}
+
+		} else {
+			return nil, fmt.Errorf("error: both width and height can't be set. Use dimensions instead")
+		}
+
+	} else if len(dimensions) == 0 {
+		// This condition calculates aspect ratio according to terminal height
+
+		terminalWidth, terminalHeight, err := winsize.GetTerminalSize()
+		if err != nil {
+			return nil, err
+		}
+
+		asciiHeight = terminalHeight - 1
+		asciiWidth = int(float64(asciiHeight) * aspectRatio)
+		asciiWidth = int(2 * float64(asciiWidth))
+
+		// If ascii width exceeds terminal width, change ratio with respect to terminal width
+		if asciiWidth >= terminalWidth {
+			asciiWidth = terminalWidth - 1
+			asciiHeight = int(float64(asciiWidth) / aspectRatio)
+			asciiHeight = int(0.5 * float64(asciiHeight))
+		}
+
+	} else {
+		// Else, set passed dimensions
+
+		asciiWidth = dimensions[0]
+		asciiHeight = dimensions[1]
+	}
+
+	// Because one braille character has 8 dots (4 rows and 2 columns)
+	if isBraille {
+		asciiWidth *= 2
+		asciiHeight *= 4
+	}
+	smallImg = imaging.Resize(img, asciiWidth, asciiHeight, imaging.Lanczos)
+
+	return smallImg, nil
+}
+
+func reverse(imgSet [][]AsciiPixel, flipX, flipY bool) [][]AsciiPixel {
+
+	if flipX {
+		for _, row := range imgSet {
+			for i, j := 0, len(row)-1; i < j; i, j = i+1, j-1 {
+				row[i], row[j] = row[j], row[i]
+			}
+		}
+	}
+
+	if flipY {
+		for i, j := 0, len(imgSet)-1; i < j; i, j = i+1, j-1 {
+			imgSet[i], imgSet[j] = imgSet[j], imgSet[i]
+		}
+	}
+
+	return imgSet
+}
+
+var termColorLevel string = gookitColor.TermColorLevel().String()
+
+// This functions calculates terminal color level between rgb colors and 256-colors
+// and returns the character with escape codes appropriately
+func getColoredCharForTerm(r, g, b uint8, char string, background bool) (string, error) {
+	var coloredChar string
+
+	if termColorLevel == "millions" {
+		colorRenderer := gookitColor.RGB(uint8(r), uint8(g), uint8(b), background)
+		coloredChar = colorRenderer.Sprintf("%v", char)
+
+	} else if termColorLevel == "hundreds" {
+		colorRenderer := gookitColor.RGB(uint8(r), uint8(g), uint8(b), background).C256()
+		coloredChar = colorRenderer.Sprintf("%v", char)
+
+	} else {
+		return "", fmt.Errorf("your terminal supports neither 24-bit nor 8-bit colors. Other coloring options aren't available")
+	}
+
+	return coloredChar, nil
+}

snapcraft.yaml

@@ -1,10 +1,11 @@
 name: ascii-image-converter
 base: core18 
-version: "1.6.0"
+version: "1.13.1"
 summary: Convert images and gifs into ascii art
 description: |
   ascii-image-converter is a command-line tool that converts images into ascii art and prints
-  them out onto the console. Supported input formats are JPEG/JPG, PNG, WEBP, BMP, TIFF/TIF and GIF
+  them out onto the console. Supported input formats are JPEG/JPG, PNG, WEBP, BMP, TIFF/TIF and GIF.
+  Now supports braille art.
 
 grade: stable
 confinement: strict