feat: Implement Phase 5.2 - Advanced WASM features for media processing

  - Add comprehensive EXIF data extraction support (camera info, GPS, lens data)
  - Implement histogram analysis for RGB and luminance channels
  - Add exposure detection (overexposed/underexposed warnings)
  - Implement color space detection (sRGB, Adobe RGB, CMYK, grayscale)
  - Add bit depth detection (8-bit, 16-bit, 32-bit/HDR)
  - Detect progressive JPEG and interlaced PNG formats
  - Add animated WebP detection with frame count
  - Implement JPEG quality estimation
  - Add memory efficiency tracking with buffer management
  - Export new types in index.ts (ColorSpace, ExifData, HistogramData)
  - Add 21 comprehensive tests for advanced WASM features
  - All 91 media tests passing

Author: julesl23

src/index.ts

@@ -47,5 +47,8 @@ export type {
   ImageMetadata,
   MediaOptions,
   InitializeOptions,
-  ImageFormat
+  ImageFormat,
+  ColorSpace,
+  ExifData,
+  HistogramData
 } from './media/types.js';

src/media/types.ts

@@ -3,6 +3,63 @@
  */
 export type ImageFormat = 'jpeg' | 'png' | 'webp' | 'gif' | 'bmp' | 'unknown';
 
+/**
+ * Color space types
+ */
+export type ColorSpace = 'srgb' | 'adobergb' | 'rgb' | 'cmyk' | 'gray' | 'lab' | 'xyz';
+
+/**
+ * EXIF data structure
+ */
+export interface ExifData {
+  /** Camera manufacturer */
+  make?: string;
+  /** Camera model */
+  model?: string;
+  /** Image orientation (1-8) */
+  orientation?: number;
+  /** Date and time of original capture */
+  dateTime?: string;
+  /** Exposure time in seconds */
+  exposureTime?: number;
+  /** F-number (aperture) */
+  fNumber?: number;
+  /** ISO speed rating */
+  iso?: number;
+  /** Focal length in mm */
+  focalLength?: number;
+  /** Flash fired */
+  flash?: boolean;
+  /** Lens model */
+  lensModel?: string;
+  /** GPS latitude */
+  gpsLatitude?: number;
+  /** GPS longitude */
+  gpsLongitude?: number;
+  /** GPS altitude in meters */
+  gpsAltitude?: number;
+  /** Copyright information */
+  copyright?: string;
+  /** Artist/photographer */
+  artist?: string;
+  /** Software used */
+  software?: string;
+}
+
+/**
+ * Histogram data for image analysis
+ */
+export interface HistogramData {
+  /** Red channel histogram (256 values) */
+  r: Uint32Array;
+  /** Green channel histogram (256 values) */
+  g: Uint32Array;
+  /** Blue channel histogram (256 values) */
+  b: Uint32Array;
+  /** Luminance histogram (256 values) */
+  luminance: Uint32Array;
+}
+
 /**
  * Metadata extracted from an image
  */
@@ -13,14 +70,36 @@ export interface ImageMetadata {
   height: number;
   /** Detected image format */
   format: ImageFormat;
+  /** MIME type */
+  mimeType?: string;
   /** Whether the image has an alpha channel (transparency) */
   hasAlpha?: boolean;
   /** EXIF metadata if available */
-  exif?: Record<string, any>;
+  exif?: ExifData;
   /** File size in bytes */
   size?: number;
   /** Source of metadata extraction (for debugging) */
   source?: 'wasm' | 'canvas' | 'fallback';
+  /** Color space of the image */
+  colorSpace?: ColorSpace;
+  /** Bit depth per channel */
+  bitDepth?: number;
+  /** Whether this is an HDR image */
+  isHDR?: boolean;
+  /** Histogram data for exposure analysis */
+  histogram?: HistogramData;
+  /** Exposure warning based on histogram analysis */
+  exposureWarning?: 'overexposed' | 'underexposed' | 'normal';
+  /** Whether the image uses progressive/interlaced encoding */
+  isProgressive?: boolean;
+  /** Whether the image uses interlaced encoding (PNG) */
+  isInterlaced?: boolean;
+  /** Whether the image is animated */
+  isAnimated?: boolean;
+  /** Number of frames (for animated images) */
+  frameCount?: number;
+  /** Estimated JPEG quality (0-100) */
+  estimatedQuality?: number;
 }
 
 /**
@@ -55,4 +134,6 @@ export interface WASMModule {
   extractMetadata(data: Uint8Array): ImageMetadata | undefined;
   /** Free allocated memory */
   cleanup(): void;
+  /** Get count of allocated buffers (for testing) */
+  getAllocatedBufferCount?(): number;
 }