fix: add tests + handle custom video tags

README.md

@@ -72,11 +72,15 @@ opts = { height: 100, width: 100 }
 opts = { quality: 80 }
 ```
 
-##### Preserve EXIF Data
+##### Preserving metadata
+
+By default, all metadata is removed from downsized images.
+This option will keep all EXIF / IPTC / XMP metadata in the target files.
+
+When setting this option to true, images will no longer be auto-rotated.
 
 ```js
-// note: this will no longer auto-orient images according to its EXIF data
-opts = { preserveExif: true }
+opts = { keepMetadata: true }
 ```
 
 ##### Watermark
@@ -227,10 +231,13 @@ opts = { framerate: 60 }
 opts = { framerate: 0 }   // preserve the original source video's FPS
 ```
 
-##### Preserve Metadata
+##### Preserving Metadata
+
+By default, all metadata is removed from the target video.
+This option preserves the metadata.
 
 ```js
-opts = { preserveMetadata: true }
+opts = { keepMetadata: true }
 ```
 
 ##### Conversion progress

lib/image/gmagick.js

@@ -6,7 +6,7 @@ exports.prepare = function (source, options) {
   // start processing with GraphicsMagick
   const image = gm(source)
 
-  if (!options.preserveExif) {
+  if (!options.keepMetadata) {
     // read baked-in orientation info, and output a rotated image with orientation=0
     // note: this strips EXIF data
     image.autoOrient()

lib/video/ffargs.js

@@ -11,7 +11,7 @@ const ENCODER_CRF = {
 }
 
 exports.prepare = function (source, target, options) {
-  // output framerate
+  // overwrite the file if already exists
   const args = ['-y']
 
   // IF VAAPI acceleration needs to go before -i input files
@@ -30,8 +30,13 @@ exports.prepare = function (source, target, options) {
   // misc options
   args.push('-vsync', '2', '-movflags', '+faststart')
 
-  if (options.preserveMetadata) {
-    args.push('-map_metadata', 0)
+  // remove metadata if required
+  if (options.keepMetadata) {
+    // the second argument is required
+    // to keep non-standard tags like <com.apple.quicktime.location.ISO6709>
+    args.push('-map_metadata', '0', '-movflags', 'use_metadata_tags')
+  } else {
+    args.push('-map_metadata', -1)
   }
 
   // audio bitrate

test/integration/diff.js

@@ -40,6 +40,17 @@ exports.video = function (args, done) {
   })
 }
 
+exports.metadata = function (type, args, done) {
+  const input = `test-data/input/${args.input}`
+  const actual = `test-data/actual/${args.input}`
+  convert[type](input, actual, args.options, (err) => {
+    const output = childProcess.execSync(`exiftool -j -g ${actual}`)
+    const fields = JSON.parse(output)[0]
+    if (err) throw err
+    done(err, fields)
+  })
+}
+
 function compareImage (expected, actual, done) {
   const isGif = actual.match(/\.gif$/i)
   // test metadata

test/integration/image.test.js

@@ -1,3 +1,4 @@
+const should = require('should/as-function')
 const diff = require('./diff')
 
 describe('image', () => {
@@ -156,6 +157,30 @@ describe('image', () => {
     }, done)
   })
 
+  it('removes all metadata by default', done => {
+    diff.metadata('image', {
+      input: 'images/metadata.jpg',
+      options: { height: 150 }
+    }, (err, fields) => {
+      should(err).be.undefined()
+      should(fields).not.have.properties(['EXIF', 'XMP', 'IPTC'])
+      done()
+    })
+  })
+
+  it('can optionally keep metadata', done => {
+    diff.metadata('image', {
+      input: 'images/metadata.jpg',
+      options: { height: 150, keepMetadata: true }
+    }, (err, fields) => {
+      should(err).be.undefined()
+      should(fields).have.propertyByPath('EXIF', 'ImageDescription').eql('Red bike')
+      should(fields).have.propertyByPath('XMP', 'Subject').eql('Bike')
+      should(fields).have.propertyByPath('IPTC', 'Keywords').eql('bike')
+      done()
+    })
+  })
+
   const ORIENTATIONS = [1, 2, 3, 4, 5, 6, 7, 8]
 
   ORIENTATIONS.forEach((orientation) => {

test/integration/video.test.js

@@ -1,3 +1,4 @@
+const should = require('should/as-function')
 const assert = require('assert')
 const diff = require('./diff')
 const convert = require('../../lib/index')
@@ -65,6 +66,30 @@ describe('video', () => {
     }, done)
   })
 
+  it('removes metadata by default', done => {
+    diff.metadata('video', {
+      input: 'videos/metadata.mp4',
+      options: {}
+    }, (err, fields) => {
+      should(err).be.null()
+      should(fields).not.have.propertyByPath('QuickTime', 'Title')
+      should(fields).not.have.propertyByPath('QuickTime', 'GPSCoordinates')
+      done()
+    })
+  })
+
+  it('can optionally keep metadata', done => {
+    diff.metadata('video', {
+      input: 'videos/metadata.mp4',
+      options: { keepMetadata: true }
+    }, (err, fields) => {
+      should(err).be.null()
+      should(fields).have.propertyByPath('QuickTime', 'Title').eql('Cool video')
+      should(fields).have.propertyByPath('QuickTime', 'GPSCoordinates').eql('60 deg 0\' 0.00" N, 10 deg 0\' 0.00" E, 0 m Above Sea Level')
+      done()
+    })
+  })
+
   it('can report progress when processing videos', done => {
     const report = []
     const input = 'test-data/input/videos/big_buck_bunny.mp4'