Merge pull request #2 from githubocto/image-processing

Image processing library functions

Author: irealva

README.md

@@ -24,18 +24,19 @@ console.log(newfile)
 
 Can be found in the examples folder:
 
-* `deno run --allow-read --allow-write examples/csv-example.ts`
-* `deno run --allow-read --allow-write examples/arquero-example.ts`
+* `deno run --allow-read --allow-write examples/csv/csv-example.ts`
+* `deno run --allow-read --allow-write examples/csv/arquero-example.ts`
+* `deno run -A examples/image/image-example.ts`
 
 ## Testing
 
 Run all the tests:
 
-`deno test --allow-read --allow-write tests/*`
+`deno test -A tests/*`
 
 Run separate tests
 
-`deno test --allow-read --allow-write tests/csv-test.ts`
+`deno test -A tests/csv-test.ts`
 
 
 ## License

examples/arquero-example.ts renamed to examples/csv/arquero-example.ts

@@ -1,6 +1,6 @@
 import * as aq from "https://cdn.skypack.dev/arquero";
 
-let t = await aq.fromCSV(await Deno.readTextFile("./examples/flights.csv"));
+let t = await aq.fromCSV(await Deno.readTextFile("./examples/csv/flights.csv"));
 
 t = t
   .derive({
@@ -22,4 +22,4 @@ t = t
   // Sort rows by duration, descreasing
   .orderby(aq.desc("duration"));
 
-await Deno.writeTextFile("./examples/flights2.csv", t.toCSV());
+await Deno.writeTextFile("./examples/csv/flights2.csv", t.toCSV());

examples/csv-example.ts renamed to examples/csv/csv-example.ts

@@ -1,8 +1,8 @@
-import { Column, DataItem, stringify } from "https://deno.land/[email protected]/encoding/csv.ts";
-import { readCSV, writeCSV } from '../csv.ts'
+import { Column, DataItem, stringify } from 'https://deno.land/[email protected]/encoding/csv.ts';
+import { readCSV, writeCSV } from 'https://deno.land/x/[email protected]/mod.ts'
 
 // Path to a csv file
-const csvPath = './examples/read-example.csv';
+const csvPath = './examples/csv/prices.csv';
 
 /* 
 Parse a csv file and return a string[][]
@@ -98,7 +98,7 @@ const columns: Column[] = ["name", "age"];
 
 // we have to stringify the data with a row header
 const dataString = await stringify(data, columns)
-writeCSV('./examples/write-example.csv', dataString)
+writeCSV('./examples/csv/names.csv', dataString)
 
 /*
 Write one of the previously parsed csv examples
@@ -111,4 +111,4 @@ Three,-0.3,$3000
 const data2 = parseColumnCSV as DataItem[]; // have to recast the output
 const columns2: Column[] = ["id", "quantity", "cost"];
 const dataString2 = await stringify(data2, columns2)
-writeCSV('./examples/write-example2.csv', dataString2)
+writeCSV('./examples/csv/prices-write.csv', dataString2)

examples/flights.csv renamed to examples/csv/flights.csv

@@ -1,3 +1,3 @@
-name,age
-Rick,70
-Smith,14
+name,age
+Rick,70
+Smith,14

examples/flights2.csv renamed to examples/csv/flights2.csv

@@ -0,0 +1,29 @@
+import { loadImage, loadImageBytes } from '../../image.ts'
+import { Image } from 'https://cdn.deno.land/imagescript/versions/1.2.0/raw/mod.ts'; // library for image manipulations
+
+const url = 'https://api.creativecommons.engineering/v1/thumbs/c8fe5f5b-cc1a-4794-91c5-7488c60f4914'
+const url2 = 'https://live.staticflickr.com/962/41906373431_72c25d0dfd_b.jpg'
+const url3 = 'https://i.giphy.com/media/5wWf7HapUvpOumiXZRK/giphy.gif'
+
+// Can specify a filename to rename the image
+// (image url, path to save image, image to save name)
+loadImage(url, './examples/image/', 'cat')
+
+// Image will be saved with the default name if not included
+loadImage(url2, './examples/image/')
+
+// Can load gifs, pngs, jpgs
+loadImage(url3, './examples/image/', 'cat-gif')
+
+// Image manipulation example - reading from a file
+const bytes = await Deno.readFile('./examples/image/cat.jpeg') // local file
+const image = await Image.decode(bytes);
+image.crop(image.width/4, image.height/4, image.width/2, image.height/2); // x, y, width, height
+await Deno.writeFile('./examples/image/cat-cropped.jpeg', await image.encode());
+
+// Image manipulation example - fetching from a url
+const { imageBytes, mimeType } = await loadImageBytes(url) // url
+const image2 = await Image.decode(imageBytes);
+image2.resize(image2.width/2, image2.height/2)
+image2.opacity(0.5).invert()
+await Deno.writeFile('./examples/image/cat-resized.jpeg', await image2.encode());

examples/write-example.csv renamed to examples/csv/names.csv

@@ -0,0 +1,27 @@
+import { mime } from "https://cdn.deno.land/mimetypes/versions/v1.0.0/raw/mod.ts"
+import { urlParse } from 'https://cdn.deno.land/url_parse/versions/1.0.0/raw/mod.ts';
+import { basename } from "https://deno.land/[email protected]/path/mod.ts";
+
+export async function loadImageBytes(url: string) {
+    const response = await fetch(url); // fetch an image
+    const mimeType = response.headers.get('content-type');
+    const imageBytes = new Uint8Array(await response.arrayBuffer());
+    return { imageBytes, mimeType }
+}
+
+export async function loadImage(url: string, path: string, name?: string) {
+    const { imageBytes, mimeType } = await loadImageBytes(url)
+    const extension = mime.getExtension(mimeType as string);
+    let imagePath
+
+    if (name) {
+        imagePath = `${path}${name}.${extension}`
+
+    } else {
+        let defaultName = basename(urlParse(url).pathname)
+        defaultName = defaultName.split('.')[0]
+        imagePath = `${path}${defaultName}.${extension}`
+    }
+
+    await Deno.writeFile(imagePath, imageBytes); // create a jpg file with Deno
+}

examples/write-example2.csv renamed to examples/csv/prices-write.csv

@@ -1,2 +1,3 @@
 export * from './json.ts'
 export * from './csv.ts'
+export * from './image.ts'

examples/read-example.csv renamed to examples/csv/prices.csv

@@ -1,8 +1,8 @@
 import { assertArrayIncludes } from "https://deno.land/[email protected]/testing/asserts.ts"
 import { readCSV, writeCSV } from '../csv.ts'
 
-const csvReadPath = './examples/read-example.csv'
-const csvWritePath = './examples/write-example.csv'
+const csvReadPath = './examples/csv/prices.csv'
+const csvWritePath = './examples/csv/names.csv'
 
 Deno.test("reads a csv file", async () => {
     const csv = await readCSV(csvReadPath) as ArrayLike<unknown>

examples/image/41906373431_72c25d0dfd_b.jpeg

@@ -0,0 +1,10 @@
+import { assertEquals } from "https://deno.land/[email protected]/testing/asserts.ts"
+import { loadImage } from '../image.ts'
+
+const url = 'https://api.creativecommons.engineering/v1/thumbs/c8fe5f5b-cc1a-4794-91c5-7488c60f4914'
+
+Deno.test("loads an image", async () => {
+    await loadImage(url, './examples/image/', 'cat')
+    const bytes = await Deno.readFile('./examples/image/cat.jpeg') // local file
+    assertEquals(bytes.length, 76507)
+});