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first pass at performance tweaks. work with a direct int[] of pixels

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Gered 2014-03-31 17:48:47 -04:00
parent f62a2ca558
commit 5baeadb0f5
1 changed files with 46 additions and 34 deletions
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src/toascii/models/image.clj
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@ -1,7 +1,7 @@
(ns toascii.models.image
"Largely based on the Claskii library: https://github.com/LauJensen/Claskii"
(:import (java.awt RenderingHints Graphics2D Image)
(java.awt.image BufferedImage)
(java.awt.image BufferedImage Raster)
(javax.imageio ImageIO)
(java.io File))
(:require [clojure.string :as str]
@ -12,46 +12,43 @@
(def ascii-chars [\# \A \@ \% \$ \+ \= \* \: \, \. \space])
(def num-ascii-chars (count ascii-chars))
(defn- get-css-color-attr [r g b]
(format "color: #%02x%02x%02x;" r g b))
(defn- get-color-brightness [r g b]
(int
(Math/sqrt
(+ (* r r 0.241)
(* g g 0.691)
(* b b 0.068)))))
(defn- get-pixel [^BufferedImage image x y]
(let [argb (.getRGB image x y)]
[(bit-shift-right (bit-and 0xff000000 argb) 24)
(bit-shift-right (bit-and 0x00ff0000 argb) 16)
(bit-shift-right (bit-and 0x0000ff00 argb) 8)
(bit-and 0x000000ff argb)]))
(defn- get-ascii-pixel [^BufferedImage image x y color?]
(let [[a r g b] (get-pixel image x y)
peak (get-color-brightness r g b)
(defn- add-pixel [argb ^StringBuilder sb color?]
(let [r (bit-shift-right (bit-and 0x00ff0000 argb) 16)
g (bit-shift-right (bit-and 0x0000ff00 argb) 8)
b (bit-and 0x000000ff argb)
peak (int
(Math/sqrt
(+ (* r r 0.241)
(* g g 0.691)
(* b b 0.068))))
char-index (if (zero? peak)
(dec num-ascii-chars)
(dec (int (* num-ascii-chars (/ peak 255)))))
pixel-char (nth ascii-chars (if (pos? char-index) char-index 0))]
(if color?
[:span {:style (get-css-color-attr r g b)} pixel-char]
; <span style="color: rgb(255, 255, 255);">X</span>
(doto sb
(.append "<span style=\"color: rgb(")
(.append r)
(.append ",")
(.append g)
(.append ",")
(.append b)
(.append ");\">")
(.append pixel-char)
(.append "</span>"))
pixel-char)))
(defn- pixels->ascii [^BufferedImage image color?]
(let [width (.getWidth image)
ascii-image (for [y (range (.getHeight image))
x (range (.getWidth image))]
(get-ascii-pixel image x y color?))
output (->> ascii-image
(partition width)
(map #(conj % (if color? [:br] \newline)))
(apply concat))]
(if color?
(html output)
(str/join output))))
(let [width (.getWidth image)
height (.getHeight image)
sb (StringBuilder.)
pixels (.getDataElements (.getRaster image) 0 0 width height nil)]
(dotimes [y height]
(dotimes [x width]
(add-pixel (aget pixels (+ x (* y width))) sb color?))
(.append sb (if color? "<br>" \newline)))
(.toString sb)))
(defn get-image-by-url
(^BufferedImage [^String url]
@ -97,4 +94,19 @@
(pixels->ascii final-image color?))))
(defn wrap-pre-tag [s]
(str "<pre style=\"font-size:6pt; letter-spacing:1px; line-height:5pt; font-weight:bold;\">" s "</pre>"))
(str "<pre style=\"font-size:6pt; letter-spacing:1px; line-height:5pt; font-weight:bold;\">" s "</pre>"))
#_(require '[criterium.core :as c])
#_(c/bench
(let [f (File. "./test/images/test.png")
image (get-image-by-file f)
ascii (convert-image image true)]
(count ascii)))
#_(let [f (File. "./test/images/test.png")
image (get-image-by-file f)
ascii (convert-image image true)]
(count ascii))