Release Image Tools 0.1.0

2026-09-01 02:47:11 +02:00
commit 83926457b2
76 changed files with 11815 additions and 0 deletions
@@ -0,0 +1,185 @@
+export const VALID_PNG_BASE64 =
+  "iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAQAAAC1HAwCAAAAC0lEQVR42mNk+A8AAQUBAScY42YAAAAASUVORK5CYII=";
+
+export function pngFixture(
+  width: number,
+  height: number,
+  options: {
+    readonly animated?: boolean;
+    readonly exif?: boolean;
+    readonly text?: boolean;
+    readonly paddingBytes?: number;
+  } = {},
+): Uint8Array {
+  const chunks: number[][] = [
+    chunk("IHDR", [...u32be(width), ...u32be(height), 8, 6, 0, 0, 0]),
+  ];
+  if (options.paddingBytes) {
+    chunks.push(chunk("ruSt", new Array<number>(options.paddingBytes).fill(0)));
+  }
+  if (options.animated) chunks.push(chunk("acTL", [...u32be(2), ...u32be(0)]));
+  if (options.exif) chunks.push(chunk("eXIf", tiffOrientation(6)));
+  if (options.text) chunks.push(chunk("tEXt", asciiBytes("Comment\0fixture")));
+  chunks.push(chunk("IDAT", []));
+  return Uint8Array.from([
+    0x89,
+    0x50,
+    0x4e,
+    0x47,
+    0x0d,
+    0x0a,
+    0x1a,
+    0x0a,
+    ...chunks.flat(),
+  ]);
+}
+
+export function jpegFixture(
+  width: number,
+  height: number,
+  options: {
+    readonly orientation?: number;
+    readonly multiPicture?: boolean;
+  } = {},
+): Uint8Array {
+  const segments: number[][] = [];
+  if (options.orientation) {
+    segments.push(
+      jpegSegment(0xe1, [
+        ...asciiBytes("Exif\0\0"),
+        ...tiffOrientation(options.orientation),
+      ]),
+    );
+  }
+  if (options.multiPicture)
+    segments.push(jpegSegment(0xe2, asciiBytes("MPF\0fixture")));
+  segments.push(
+    jpegSegment(0xc0, [
+      8,
+      ...u16be(height),
+      ...u16be(width),
+      3,
+      1,
+      0x11,
+      0,
+      2,
+      0x11,
+      0,
+      3,
+      0x11,
+      0,
+    ]),
+  );
+  return Uint8Array.from([0xff, 0xd8, ...segments.flat(), 0xff, 0xd9]);
+}
+
+export function webpFixture(
+  width: number,
+  height: number,
+  options: {
+    readonly animated?: boolean;
+    readonly alpha?: boolean;
+    readonly metadata?: boolean;
+    readonly animationChunk?: boolean;
+    readonly paddingBytes?: number;
+  } = {},
+): Uint8Array {
+  const flags =
+    (options.animated ? 0x02 : 0) |
+    (options.alpha ? 0x10 : 0) |
+    (options.metadata ? 0x2c : 0);
+  const payload = [flags, 0, 0, 0, ...u24le(width - 1), ...u24le(height - 1)];
+  const vp8x = riffChunk("VP8X", payload);
+  const padding = options.paddingBytes
+    ? riffChunk("JUNK", new Array<number>(options.paddingBytes).fill(0))
+    : [];
+  const animation = options.animationChunk
+    ? riffChunk("ANIM", new Array<number>(6).fill(0))
+    : [];
+  const chunks = [...vp8x, ...padding, ...animation];
+  const size = 4 + chunks.length;
+  return Uint8Array.from([
+    ...asciiBytes("RIFF"),
+    ...u32le(size),
+    ...asciiBytes("WEBP"),
+    ...chunks,
+  ]);
+}
+
+function jpegSegment(marker: number, data: readonly number[]): number[] {
+  return [0xff, marker, ...u16be(data.length + 2), ...data];
+}
+
+function chunk(type: string, data: readonly number[]): number[] {
+  return [...u32be(data.length), ...asciiBytes(type), ...data, 0, 0, 0, 0];
+}
+
+function riffChunk(type: string, data: readonly number[]): number[] {
+  return [
+    ...asciiBytes(type),
+    ...u32le(data.length),
+    ...data,
+    ...(data.length % 2 ? [0] : []),
+  ];
+}
+
+function tiffOrientation(orientation: number): number[] {
+  return [
+    0x49,
+    0x49,
+    0x2a,
+    0x00,
+    0x08,
+    0x00,
+    0x00,
+    0x00,
+    0x01,
+    0x00,
+    0x12,
+    0x01,
+    0x03,
+    0x00,
+    0x01,
+    0x00,
+    0x00,
+    0x00,
+    orientation,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+    0x00,
+  ];
+}
+
+function asciiBytes(value: string): number[] {
+  return Array.from(value, (character) => character.charCodeAt(0));
+}
+
+function u16be(value: number): number[] {
+  return [(value >>> 8) & 0xff, value & 0xff];
+}
+
+function u32be(value: number): number[] {
+  return [
+    (value >>> 24) & 0xff,
+    (value >>> 16) & 0xff,
+    (value >>> 8) & 0xff,
+    value & 0xff,
+  ];
+}
+
+function u32le(value: number): number[] {
+  return [
+    value & 0xff,
+    (value >>> 8) & 0xff,
+    (value >>> 16) & 0xff,
+    (value >>> 24) & 0xff,
+  ];
+}
+
+function u24le(value: number): number[] {
+  return [value & 0xff, (value >>> 8) & 0xff, (value >>> 16) & 0xff];
+}