feat: exif

README.md

@@ -15,6 +15,7 @@
 - Safety guard: if optimized output is not smaller, original file is kept.
 - Backed by proven tools: ImageMagick, SVGO, Gifsicle, MozJPEG, and FFmpeg.
 - Supports image and video optimization.
+- Strips metadata by default for smaller outputs.
 - Resizing supports percentage values (`50%`), max file size targets (`100kB`, images only), width (`w960`), & height (`h480`).
 
 ## Usage
@@ -28,6 +29,7 @@ npx -y optimo public/media/banner.png --resize 50% # resize + optimize
 npx -y optimo public/media/banner.png --resize 100kB # resize to max file size
 npx -y optimo public/media/banner.png --resize w960 # resize to max width
 npx -y optimo public/media/banner.png --resize h480 # resize to max height
+npx -y optimo public/media/banner.jpg --preserve-exif # keep EXIF metadata
 npx -y optimo public/media/banner.png --data-url # print optimized image as data URL
 npx -y optimo public/media/banner.heic --dry-run --verbose # inspect unsupported failures
 npx -y optimo public/media/clip.mp4 # optimize a video
@@ -52,6 +54,7 @@ Mode behavior:
 - default: lossless-first pipeline.
 - `-l, --losy`: lossy + lossless pass per matching compressor.
 - `-m, --mute`: remove audio tracks from video outputs (default: `true`; use `--mute false` to keep audio).
+- `-p, --preserve-exif`: preserve EXIF metadata on image outputs (default: `false`).
 - `-u, --data-url`: return optimized image as data URL (single file only; image only).
 - `-v, --verbose`: print debug logs (selected pipeline, binaries, executed commands, and errors).
 
@@ -73,6 +76,7 @@ const optimo = require('optimo')
 await optimo.file('/absolute/path/image.jpg', {
   dryRun: false,
   losy: false,
+  preserveExif: false,
   format: 'webp',
   resize: '50%',
   onLogs: console.log

bin/help.js

@@ -10,6 +10,7 @@ Usage
 Options
   -l, --losy  Enable lossy + lossless passes (default: false)
   -m, --mute  Remove audio tracks from videos (default: true)
+  -p, --preserve-exif  Preserve EXIF metadata (default: false)
   -u, --data-url  Return optimized image as data URL (file input only)
   -d, --dry-run  Show what would be optimized without making changes
   -f, --format   Convert output format (e.g. jpeg, webp, avif)
@@ -18,6 +19,7 @@ Options
 
 Examples
   $ optimo image.jpg # optimize a single image in place
+  $ optimo image.jpg --preserve-exif # keep EXIF metadata on output image
   $ optimo image.jpg --losy # run lossy + lossless optimization passes
   $ optimo clip.mp4 --mute # optimize video and remove audio track
   $ optimo clip.mp4 --mute false # optimize video and keep audio track

bin/index.js

@@ -13,6 +13,7 @@ const INSTALL_HINTS = {
   'mozjpegtran/jpegtran': 'brew install mozjpeg',
   'magick:jxl': 'brew install imagemagick-full && brew link --overwrite --force imagemagick-full'
 }
+const FALSE_VALUES = ['false', '0', 'no', 'off']
 
 async function main () {
   const argv = mri(process.argv.slice(2), {
@@ -22,6 +23,7 @@ async function main () {
       format: 'f',
       losy: 'l',
       mute: 'm',
+      'preserve-exif': 'p',
       resize: 'r',
       silent: 's',
       verbose: 'v'
@@ -30,7 +32,9 @@ async function main () {
 
   const input = argv._[0]
   const dataUrl = argv['data-url'] === true
-  const mute = argv.mute === undefined ? true : !['false', '0', 'no', 'off'].includes(String(argv.mute).toLowerCase())
+  const isEnabled = value => !FALSE_VALUES.includes(String(value).toLowerCase())
+  const mute = argv.mute === undefined ? true : isEnabled(argv.mute)
+  const preserveExif = argv['preserve-exif'] === undefined ? false : isEnabled(argv['preserve-exif'])
   let resize = argv.resize
 
   if (resize !== undefined && resize !== null) {
@@ -59,6 +63,7 @@ async function main () {
   const result = await fn(input, {
     losy: argv.losy,
     mute,
+    preserveExif,
     dryRun: argv['dry-run'],
     dataUrl,
     format: argv.format,

src/compressor/magick.js

@@ -48,7 +48,6 @@ const withMeta = (format, fn, { delegate } = {}) => {
 }
 
 const MAGICK_JPEG_LOSSY_FLAGS = [
-  '-strip',
   '-sampling-factor',
   '4:2:0',
   '-define',
@@ -65,32 +64,31 @@ const MAGICK_JPEG_LOSSLESS_FLAGS = ['-define', 'jpeg:optimize-coding=true', '-in
 
 const MAGICK_PNG_LOSSLESS_FLAGS = []
 const MAGICK_PNG_LOSSY_FLAGS = [
-  '-strip',
   '-define',
   'png:exclude-chunks=all',
   '-define',
   'png:include-chunks=tRNS,gAMA'
 ]
 
-const MAGICK_GIF_FLAGS = ['-strip', '-coalesce', '-layers', 'OptimizePlus']
+const MAGICK_GIF_FLAGS = ['-coalesce', '-layers', 'OptimizePlus']
 
-const MAGICK_WEBP_LOSSY_FLAGS = ['-strip', '-define', 'webp:method=6', '-define', 'webp:thread-level=1', '-quality', '80']
-const MAGICK_WEBP_LOSSLESS_FLAGS = ['-strip', '-define', 'webp:method=6', '-define', 'webp:thread-level=1', '-quality', '100']
+const MAGICK_WEBP_LOSSY_FLAGS = ['-define', 'webp:method=6', '-define', 'webp:thread-level=1', '-quality', '80']
+const MAGICK_WEBP_LOSSLESS_FLAGS = ['-define', 'webp:method=6', '-define', 'webp:thread-level=1', '-quality', '100']
 
-const MAGICK_AVIF_FLAGS = ['-strip', '-define', 'heic:speed=1', '-quality', '50']
+const MAGICK_AVIF_FLAGS = ['-define', 'heic:speed=1', '-quality', '50']
 
-const MAGICK_HEIC_LOSSY_FLAGS = ['-strip', '-quality', '75']
-const MAGICK_HEIC_LOSSLESS_FLAGS = ['-strip', '-quality', '100']
+const MAGICK_HEIC_LOSSY_FLAGS = ['-quality', '75']
+const MAGICK_HEIC_LOSSLESS_FLAGS = ['-quality', '100']
 
-const MAGICK_JXL_FLAGS = ['-strip', '-define', 'jxl:effort=9', '-quality', '75']
+const MAGICK_JXL_FLAGS = ['-define', 'jxl:effort=9', '-quality', '75']
 
-const MAGICK_SVG_FLAGS = ['-strip']
+const MAGICK_SVG_FLAGS = []
 
-const MAGICK_GENERIC_FLAGS = ['-strip']
+const MAGICK_GENERIC_FLAGS = []
 
-const flagsByExt = ({ ext, losy = false }) => {
+const flagsByExt = ({ ext, losy = false, preserveExif = false }) => {
   if (ext === '.jpg' || ext === '.jpeg') return losy ? MAGICK_JPEG_LOSSY_FLAGS : MAGICK_JPEG_LOSSLESS_FLAGS
-  if (ext === '.png') return losy ? MAGICK_PNG_LOSSY_FLAGS : MAGICK_PNG_LOSSLESS_FLAGS
+  if (ext === '.png') return losy && !preserveExif ? MAGICK_PNG_LOSSY_FLAGS : MAGICK_PNG_LOSSLESS_FLAGS
   if (ext === '.gif') return MAGICK_GIF_FLAGS
   if (ext === '.webp') return losy ? MAGICK_WEBP_LOSSY_FLAGS : MAGICK_WEBP_LOSSLESS_FLAGS
   if (ext === '.avif') return MAGICK_AVIF_FLAGS
@@ -169,9 +167,9 @@ const writePng = async ({ inputPath, outputPath, flags, resizeGeometry }) => {
   }
 }
 
-const runOnce = async ({ inputPath, outputPath, resizeGeometry, losy = false }) => {
+const runOnce = async ({ inputPath, outputPath, resizeGeometry, losy = false, preserveExif = false }) => {
   const ext = path.extname(outputPath).toLowerCase()
-  const flags = flagsByExt({ ext, losy })
+  const flags = [...(preserveExif ? [] : ['-strip']), ...flagsByExt({ ext, losy, preserveExif })]
 
   if (ext === '.png') {
     return writePng({ inputPath, outputPath, flags, resizeGeometry })
@@ -180,7 +178,7 @@ const runOnce = async ({ inputPath, outputPath, resizeGeometry, losy = false })
   return $(binaryPath, [inputPath, ...(resizeGeometry ? ['-resize', resizeGeometry] : []), ...flags, outputPath])
 }
 
-const runMaxSize = async ({ inputPath, outputPath, maxSize, losy = false }) => {
+const runMaxSize = async ({ inputPath, outputPath, maxSize, losy = false, preserveExif = false }) => {
   const resultByScale = new Map()
 
   const measureScale = async scale => {
@@ -193,7 +191,8 @@ const runMaxSize = async ({ inputPath, outputPath, maxSize, losy = false }) => {
       inputPath,
       outputPath: candidatePath,
       resizeGeometry,
-      losy
+      losy,
+      preserveExif
     })
 
     const size = (await stat(candidatePath)).size
@@ -238,13 +237,14 @@ const runMaxSize = async ({ inputPath, outputPath, maxSize, losy = false }) => {
   }
 }
 
-const run = async ({ inputPath, outputPath, resizeConfig, losy = false }) => {
+const run = async ({ inputPath, outputPath, resizeConfig, losy = false, preserveExif = false }) => {
   if (resizeConfig?.mode === 'max-size') {
     return runMaxSize({
       inputPath,
       outputPath,
       maxSize: resizeConfig.value,
-      losy
+      losy,
+      preserveExif
     })
   }
 
@@ -253,7 +253,8 @@ const run = async ({ inputPath, outputPath, resizeConfig, losy = false }) => {
       inputPath,
       outputPath,
       resizeGeometry: resizeConfig?.value,
-      losy: false
+      losy: false,
+      preserveExif
     })
   }
 
@@ -263,12 +264,14 @@ const run = async ({ inputPath, outputPath, resizeConfig, losy = false }) => {
       inputPath,
       outputPath: lossyPath,
       resizeGeometry: resizeConfig?.value,
-      losy: true
+      losy: true,
+      preserveExif
     })
     await runOnce({
       inputPath: lossyPath,
       outputPath,
-      losy: false
+      losy: false,
+      preserveExif
     })
   } finally {
     try {

src/compressor/mozjpegtran.js

@@ -17,10 +17,10 @@ const withMeta = (format, fn) => {
   return wrapped
 }
 
-const run = async ({ inputPath, outputPath, losy = false }) =>
+const run = async ({ inputPath, outputPath, preserveExif = false }) =>
   $(mozjpegtranPath, [
     '-copy',
-    losy ? 'none' : 'all',
+    preserveExif ? 'all' : 'none',
     '-optimize',
     '-progressive',
     '-outfile',

src/index.js

@@ -14,15 +14,16 @@ const toDataUrl = require('./util/to-data-url')
 const formatLog = require('./util/format-log')
 const debug = require('./util/debug')
 
-const runStepInPlaceIfSmaller = async ({ currentPath, extension, step, mute }) => {
+const runStepInPlaceIfSmaller = async ({ currentPath, extension, step, mute, preserveExif }) => {
   const candidatePath = `${currentPath}.candidate${extension}`
 
   await step({
     inputPath: currentPath,
     outputPath: candidatePath,
     resizeConfig: null,
     losy: false,
-    mute
+    mute,
+    preserveExif
   })
 
   const [currentSize, candidateSize] = await Promise.all([
@@ -38,23 +39,25 @@ const runStepInPlaceIfSmaller = async ({ currentPath, extension, step, mute }) =
   }
 }
 
-const executePipeline = async ({ pipeline, filePath, optimizedPath, resizeConfig, losy, mute }) => {
+const executePipeline = async ({ pipeline, filePath, optimizedPath, resizeConfig, losy, mute, preserveExif }) => {
   const extension = path.extname(optimizedPath) || '.tmp'
 
   await pipeline[0]({
     inputPath: filePath,
     outputPath: optimizedPath,
     resizeConfig,
     losy,
-    mute
+    mute,
+    preserveExif
   })
 
   for (const step of pipeline.slice(1)) {
     await runStepInPlaceIfSmaller({
       currentPath: optimizedPath,
       extension,
       mute,
-      step: async args => step({ ...args, losy })
+      preserveExif,
+      step: async args => step({ ...args, losy, preserveExif })
     })
   }
 
@@ -63,7 +66,7 @@ const executePipeline = async ({ pipeline, filePath, optimizedPath, resizeConfig
 
 const file = async (
   filePath,
-  { onLogs = () => {}, dryRun, format: outputFormat, resize, losy = false, mute = true, dataUrl = false } = {}
+  { onLogs = () => {}, dryRun, format: outputFormat, resize, losy = false, mute = true, preserveExif = false, dataUrl = false } = {}
 ) => {
   const outputPath = getOutputPath(filePath, outputFormat)
   const resizeConfig = parseResize(resize)
@@ -105,7 +108,8 @@ const file = async (
 
   const missingBinaries = ensureBinaries(
     getRequiredBinaries(executionPipeline, {
-      losy
+      losy,
+      preserveExif
     })
   )
 
@@ -134,7 +138,8 @@ const file = async (
         optimizedPath,
         resizeConfig,
         losy,
-        mute
+        mute,
+        preserveExif
       })
     }
   } catch (error) {