image: complete per-song album covers

- Implement perceptual hashing algorithm to efficiently cache images
- Efficiently pre-sort cover sources to make cover images load without
freezing and look more pleasing

Resolbes #342.

app/src/main/java/org/oxycblt/auxio/image/BitmapProvider.kt

@@ -94,7 +94,7 @@ constructor(
             target
                 .onConfigRequest(
                     ImageRequest.Builder(context)
-                        .data(listOf(song))
+                        .data(listOf(song.cover))
                         // Use ORIGINAL sizing, as we are not loading into any View-like component.
                         .size(Size.ORIGINAL))
                 .target(

app/src/main/java/org/oxycblt/auxio/image/CoverView.kt

@@ -48,6 +48,7 @@ import com.google.android.material.shape.MaterialShapeDrawable
 import dagger.hilt.android.AndroidEntryPoint
 import javax.inject.Inject
 import org.oxycblt.auxio.R
+import org.oxycblt.auxio.image.extractor.Cover
 import org.oxycblt.auxio.image.extractor.RoundedRectTransformation
 import org.oxycblt.auxio.image.extractor.SquareCropTransformation
 import org.oxycblt.auxio.music.Album
@@ -101,14 +102,6 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
     private val indicatorMatrixSrc = RectF()
     private val indicatorMatrixDst = RectF()
 
-    private data class Cover(
-        val songs: Collection<Song>,
-        val desc: String,
-        @DrawableRes val errorRes: Int
-    )
-
-    private var currentCover: Cover? = null
-
     init {
         // Obtain some StyledImageView attributes to use later when theming the custom view.
         @SuppressLint("CustomViewStyleable")
@@ -342,8 +335,8 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
      * @param song The [Song] to bind to the view.
      */
     fun bind(song: Song) =
-        bind(
+        bindImpl(
-            listOf(song),
+            listOf(song.cover),
             context.getString(R.string.desc_album_cover, song.album.name),
             R.drawable.ic_album_24)
 
@@ -353,8 +346,8 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
      * @param album The [Album] to bind to the view.
      */
     fun bind(album: Album) =
-        bind(
+        bindImpl(
-            album.songs,
+            album.cover.all,
             context.getString(R.string.desc_album_cover, album.name),
             R.drawable.ic_album_24)
 
@@ -364,8 +357,8 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
      * @param artist The [Artist] to bind to the view.
      */
     fun bind(artist: Artist) =
-        bind(
+        bindImpl(
-            artist.songs,
+            artist.cover.all,
             context.getString(R.string.desc_artist_image, artist.name),
             R.drawable.ic_artist_24)
 
@@ -375,8 +368,8 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
      * @param genre The [Genre] to bind to the view.
      */
     fun bind(genre: Genre) =
-        bind(
+        bindImpl(
-            genre.songs,
+            genre.cover.all,
             context.getString(R.string.desc_genre_image, genre.name),
             R.drawable.ic_genre_24)
 
@@ -386,8 +379,8 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
      * @param playlist the [Playlist] to bind.
      */
     fun bind(playlist: Playlist) =
-        bind(
+        bindImpl(
-            playlist.songs,
+            playlist.cover?.all ?: emptyList(),
             context.getString(R.string.desc_playlist_image, playlist.name),
             R.drawable.ic_playlist_24)
 
@@ -398,10 +391,13 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
      * @param desc The content description to describe the bound data.
      * @param errorRes The resource of the error drawable to use if the cover cannot be loaded.
      */
-    fun bind(songs: Collection<Song>, desc: String, @DrawableRes errorRes: Int) {
+    fun bind(songs: List<Song>, desc: String, @DrawableRes errorRes: Int) =
+        bindImpl(Cover.order(songs), desc, errorRes)
+
+    private fun bindImpl(covers: List<Cover>, desc: String, @DrawableRes errorRes: Int) {
         val request =
             ImageRequest.Builder(context)
-                .data(songs)
+                .data(covers)
                 .error(StyledDrawable(context, context.getDrawableCompat(errorRes), iconSizeRes))
                 .target(image)
 
@@ -417,7 +413,6 @@ constructor(context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr
         CoilUtils.dispose(image)
         imageLoader.enqueue(request.build())
         contentDescription = desc
-        currentCover = Cover(songs, desc, errorRes)
     }
 
     /**

app/src/main/java/org/oxycblt/auxio/image/extractor/Components.kt

@@ -24,25 +24,23 @@ import coil.key.Keyer
 import coil.request.Options
 import coil.size.Size
 import javax.inject.Inject
-import org.oxycblt.auxio.music.Song
 
-class SongKeyer @Inject constructor(private val coverExtractor: CoverExtractor) :
+class CoverKeyer @Inject constructor() : Keyer<Collection<Cover>> {
-    Keyer<Collection<Song>> {
+    override fun key(data: Collection<Cover>, options: Options) =
-    override fun key(data: Collection<Song>, options: Options) =
+        "${data.map { it.perceptualHash }.hashCode()}"
-        "${coverExtractor.computeCoverOrdering(data).hashCode()}"
 }
 
-class SongCoverFetcher
+class CoverFetcher
 private constructor(
-    private val songs: Collection<Song>,
+    private val covers: Collection<Cover>,
     private val size: Size,
     private val coverExtractor: CoverExtractor,
 ) : Fetcher {
-    override suspend fun fetch() = coverExtractor.extract(songs, size)
+    override suspend fun fetch() = coverExtractor.extract(covers, size)
 
     class Factory @Inject constructor(private val coverExtractor: CoverExtractor) :
-        Fetcher.Factory<Collection<Song>> {
+        Fetcher.Factory<Collection<Cover>> {
-        override fun create(data: Collection<Song>, options: Options, imageLoader: ImageLoader) =
+        override fun create(data: Collection<Cover>, options: Options, imageLoader: ImageLoader) =
-            SongCoverFetcher(data, options.size, coverExtractor)
+            CoverFetcher(data, options.size, coverExtractor)
     }
 }

app/src/main/java/org/oxycblt/auxio/image/extractor/Cover.kt

@@ -19,6 +19,8 @@
 package org.oxycblt.auxio.image.extractor
 
 import android.net.Uri
+import org.oxycblt.auxio.list.sort.Sort
+import org.oxycblt.auxio.music.Song
 
 /**
  * Bundle of [Uri] information used in [CoverExtractor] to ensure consistent [Uri] use when loading
@@ -29,4 +31,24 @@ import android.net.Uri
  *   an album cover.
  * @author Alexander Capehart (OxygenCobalt)
  */
-data class Cover(val perceptualHash: String?, val mediaStoreUri: Uri, val songUri: Uri)
+data class Cover(val perceptualHash: String?, val mediaStoreUri: Uri, val songUri: Uri) {
+    companion object {
+        private val FALLBACK_SORT = Sort(Sort.Mode.ByAlbum, Sort.Direction.ASCENDING)
+
+        fun order(songs: Collection<Song>) =
+            FALLBACK_SORT.songs(songs)
+                .map { it.cover }
+                .groupBy { it.perceptualHash }
+                .entries
+                .sortedByDescending { it.value.size }
+                .map { it.value.first() }
+    }
+}
+
+data class ParentCover(val single: Cover, val all: List<Cover>) {
+    companion object {
+        fun from(song: Song, songs: Collection<Song>) = from(song.cover, songs)
+
+        fun from(src: Cover, songs: Collection<Song>) = ParentCover(src, Cover.order(songs))
+    }
+}

app/src/main/java/org/oxycblt/auxio/image/extractor/CoverExtractor.kt

@@ -27,6 +27,7 @@ import android.util.Size as AndroidSize
 import androidx.core.graphics.drawable.toDrawable
 import androidx.media3.common.MediaItem
 import androidx.media3.common.MediaMetadata
+import androidx.media3.common.Metadata
 import androidx.media3.exoplayer.MetadataRetriever
 import androidx.media3.exoplayer.source.MediaSource
 import androidx.media3.extractor.metadata.flac.PictureFrame
@@ -50,8 +51,6 @@ import okio.buffer
 import okio.source
 import org.oxycblt.auxio.image.CoverMode
 import org.oxycblt.auxio.image.ImageSettings
-import org.oxycblt.auxio.list.sort.Sort
-import org.oxycblt.auxio.music.Album
 import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.util.logE
 
@@ -70,14 +69,13 @@ constructor(
     /**
      * Extract an image (in the form of [FetchResult]) to represent the given [Song]s.
      *
-     * @param songs The [Song]s to load.
+     * @param covers The [Cover]s to load.
      * @param size The [Size] of the image to load.
      * @return If four distinct album covers could be extracted from the [Song]s, a [DrawableResult]
      *   will be returned of a mosaic composed of four album covers ordered by
      *   [computeCoverOrdering]. Otherwise, a [SourceResult] of one album cover will be returned.
      */
-    suspend fun extract(songs: Collection<Song>, size: Size): FetchResult? {
+    suspend fun extract(covers: Collection<Cover>, size: Size): FetchResult? {
-        val covers = computeCoverOrdering(songs)
         val streams = mutableListOf<InputStream>()
         for (cover in covers) {
             openCoverInputStream(cover)?.let(streams::add)
@@ -108,19 +106,37 @@ constructor(
             dataSource = DataSource.DISK)
     }
 
-    /**
+    fun findCoverDataInMetadata(metadata: Metadata): InputStream? {
-     * Creates an [Album] list representing the order that album covers would be used in [extract].
+        var stream: ByteArrayInputStream? = null
-     *
+
-     * @param songs A hypothetical list of [Song]s that would be used in [extract].
+        for (i in 0 until metadata.length()) {
-     * @return A list of [Album]s first ordered by the "representation" within the [Song]s, and then
+            // We can only extract pictures from two tags with this method, ID3v2's APIC or
-     *   by their names. "Representation" is defined by how many [Song]s were found to be linked to
+            // Vorbis picture comments.
-     *   the given [Album] in the given [Song] list.
+            val pic: ByteArray?
-     */
+            val type: Int
-    fun computeCoverOrdering(songs: Collection<Song>) =
+
-        Sort(Sort.Mode.ByAlbum, Sort.Direction.ASCENDING)
+            when (val entry = metadata.get(i)) {
-            .songs(songs)
+                is ApicFrame -> {
-            .distinctBy { (it.cover.perceptualHash ?: it.uri).toString() }
+                    pic = entry.pictureData
-            .map { it.cover }
+                    type = entry.pictureType
+                }
+                is PictureFrame -> {
+                    pic = entry.pictureData
+                    type = entry.pictureType
+                }
+                else -> continue
+            }
+
+            if (type == MediaMetadata.PICTURE_TYPE_FRONT_COVER) {
+                stream = ByteArrayInputStream(pic)
+                break
+            } else if (stream == null) {
+                stream = ByteArrayInputStream(pic)
+            }
+        }
+
+        return stream
+    }
 
     private suspend fun openCoverInputStream(cover: Cover) =
         try {
@@ -165,35 +181,7 @@ constructor(
             return null
         }
 
-        var stream: ByteArrayInputStream? = null
+        return findCoverDataInMetadata(metadata)
-
-        for (i in 0 until metadata.length()) {
-            // We can only extract pictures from two tags with this method, ID3v2's APIC or
-            // Vorbis picture comments.
-            val pic: ByteArray?
-            val type: Int
-
-            when (val entry = metadata.get(i)) {
-                is ApicFrame -> {
-                    pic = entry.pictureData
-                    type = entry.pictureType
-                }
-                is PictureFrame -> {
-                    pic = entry.pictureData
-                    type = entry.pictureType
-                }
-                else -> continue
-            }
-
-            if (type == MediaMetadata.PICTURE_TYPE_FRONT_COVER) {
-                stream = ByteArrayInputStream(pic)
-                break
-            } else if (stream == null) {
-                stream = ByteArrayInputStream(pic)
-            }
-        }
-
-        return stream
     }
 
     private suspend fun extractMediaStoreCover(cover: Cover) =

app/src/main/java/org/oxycblt/auxio/image/extractor/DHash.kt

@@ -0,0 +1,59 @@
+/*
+ * Copyright (c) 2024 Auxio Project
+ * DHash.kt is part of Auxio.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+ 
+package org.oxycblt.auxio.image.extractor
+
+import android.graphics.Bitmap
+import android.graphics.Canvas
+import android.graphics.Color
+import android.graphics.ColorMatrix
+import android.graphics.ColorMatrixColorFilter
+import android.graphics.Paint
+import java.math.BigInteger
+
+fun Bitmap.dHash(hashSize: Int = 16): String {
+    // Step 1: Resize the bitmap to a fixed size
+    val resizedBitmap = Bitmap.createScaledBitmap(this, hashSize + 1, hashSize, true)
+
+    // Step 2: Convert the bitmap to grayscale
+    val grayBitmap =
+        Bitmap.createBitmap(resizedBitmap.width, resizedBitmap.height, Bitmap.Config.ARGB_8888)
+    val canvas = Canvas(grayBitmap)
+    val paint = Paint()
+    val colorMatrix = ColorMatrix()
+    colorMatrix.setSaturation(0f)
+    val filter = ColorMatrixColorFilter(colorMatrix)
+    paint.colorFilter = filter
+    canvas.drawBitmap(resizedBitmap, 0f, 0f, paint)
+
+    // Step 3: Compute the difference between adjacent pixels
+    var hash = BigInteger.valueOf(0)
+    val one = BigInteger.valueOf(1)
+    for (y in 0 until hashSize) {
+        for (x in 0 until hashSize) {
+            val pixel1 = grayBitmap.getPixel(x, y)
+            val pixel2 = grayBitmap.getPixel(x + 1, y)
+            val diff = Color.red(pixel1) - Color.red(pixel2)
+            if (diff > 0) {
+                hash = hash.or(one.shl(y * hashSize + x))
+            }
+        }
+    }
+
+    return hash.toString(16)
+}

app/src/main/java/org/oxycblt/auxio/image/extractor/ExtractorModule.kt

@@ -35,14 +35,14 @@ class ExtractorModule {
     @Provides
     fun imageLoader(
         @ApplicationContext context: Context,
-        songKeyer: SongKeyer,
+        keyer: CoverKeyer,
-        songFactory: SongCoverFetcher.Factory
+        factory: CoverFetcher.Factory
     ) =
         ImageLoader.Builder(context)
             .components {
                 // Add fetchers for Music components to make them usable with ImageRequest
-                add(songKeyer)
+                add(keyer)
-                add(songFactory)
+                add(factory)
             }
             // Use our own crossfade with error drawable support
             .transitionFactory(ErrorCrossfadeTransitionFactory())

app/src/main/java/org/oxycblt/auxio/image/service/MediaSessionBitmapLoader.kt

@@ -1,6 +1,6 @@
 /*
  * Copyright (c) 2024 Auxio Project
- * CoilBitmapLoader.kt is part of Auxio.
+ * MediaSessionBitmapLoader.kt is part of Auxio.
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -31,7 +31,7 @@ import com.google.common.util.concurrent.SettableFuture
 import dagger.hilt.android.qualifiers.ApplicationContext
 import javax.inject.Inject
 import org.oxycblt.auxio.image.BitmapProvider
-import org.oxycblt.auxio.image.extractor.SongKeyer
+import org.oxycblt.auxio.image.extractor.CoverKeyer
 import org.oxycblt.auxio.music.MusicRepository
 import org.oxycblt.auxio.music.service.MediaSessionUID
 
@@ -41,7 +41,7 @@ constructor(
     @ApplicationContext private val context: Context,
     private val musicRepository: MusicRepository,
     private val bitmapProvider: BitmapProvider,
-    private val songKeyer: SongKeyer,
+    private val keyer: CoverKeyer,
     private val imageLoader: ImageLoader,
 ) : BitmapLoader {
     override fun decodeBitmap(data: ByteArray): ListenableFuture<Bitmap> {
@@ -69,7 +69,7 @@ constructor(
                 ?: return null
         // Even launching a coroutine to obtained cached covers is enough to make the notification
         // go without covers.
-        val key = songKeyer.key(listOf(song), Options(context))
+        val key = keyer.key(listOf(song.cover), Options(context))
         if (imageLoader.memoryCache?.get(MemoryCache.Key(key)) != null) {
             future.set(imageLoader.memoryCache?.get(MemoryCache.Key(key))?.bitmap)
             return future

app/src/main/java/org/oxycblt/auxio/music/Music.kt

@@ -28,6 +28,7 @@ import kotlin.math.max
 import kotlinx.parcelize.IgnoredOnParcel
 import kotlinx.parcelize.Parcelize
 import org.oxycblt.auxio.image.extractor.Cover
+import org.oxycblt.auxio.image.extractor.ParentCover
 import org.oxycblt.auxio.list.Item
 import org.oxycblt.auxio.music.fs.MimeType
 import org.oxycblt.auxio.music.fs.Path
@@ -296,7 +297,7 @@ interface Album : MusicParent {
      */
     val releaseType: ReleaseType
     /** Cover information from the template song used for the album. */
-    val cover: Cover
+    val cover: ParentCover
     /** The duration of all songs in the album, in milliseconds. */
     val durationMs: Long
     /** The earliest date a song in this album was added, as a unix epoch timestamp. */
@@ -326,7 +327,7 @@ interface Artist : MusicParent {
      */
     val durationMs: Long?
     /** Useful information to quickly obtain a (single) cover for a Genre. */
-    val cover: Cover
+    val cover: ParentCover
     /** The [Genre]s of this artist. */
     val genres: List<Genre>
 }
@@ -342,7 +343,7 @@ interface Genre : MusicParent {
     /** The total duration of the songs in this genre, in milliseconds. */
     val durationMs: Long
     /** Useful information to quickly obtain a (single) cover for a Genre. */
-    val cover: Cover
+    val cover: ParentCover
 }
 
 /**
@@ -356,7 +357,7 @@ interface Playlist : MusicParent {
     /** The total duration of the songs in this genre, in milliseconds. */
     val durationMs: Long
     /** Useful information to quickly obtain a (single) cover for a Genre. */
-    val cover: Cover?
+    val cover: ParentCover?
 }
 
 /**

app/src/main/java/org/oxycblt/auxio/music/cache/CacheDatabase.kt

@@ -32,7 +32,7 @@ import org.oxycblt.auxio.music.info.Date
 import org.oxycblt.auxio.music.metadata.correctWhitespace
 import org.oxycblt.auxio.music.metadata.splitEscaped
 
-@Database(entities = [CachedSong::class], version = 42, exportSchema = false)
+@Database(entities = [CachedSong::class], version = 45, exportSchema = false)
 abstract class CacheDatabase : RoomDatabase() {
     abstract fun cachedSongsDao(): CachedSongsDao
 }
@@ -80,6 +80,8 @@ data class CachedSong(
     var subtitle: String? = null,
     /** @see RawSong.date */
     var date: Date? = null,
+    /** @see RawSong.coverPerceptualHash */
+    var coverPerceptualHash: String? = null,
     /** @see RawSong.albumMusicBrainzId */
     var albumMusicBrainzId: String? = null,
     /** @see RawSong.albumName */
@@ -119,6 +121,8 @@ data class CachedSong(
         rawSong.subtitle = subtitle
         rawSong.date = date
 
+        rawSong.coverPerceptualHash = coverPerceptualHash
+
         rawSong.albumMusicBrainzId = albumMusicBrainzId
         rawSong.albumName = albumName
         rawSong.albumSortName = albumSortName
@@ -167,6 +171,7 @@ data class CachedSong(
                 disc = rawSong.disc,
                 subtitle = rawSong.subtitle,
                 date = rawSong.date,
+                coverPerceptualHash = rawSong.coverPerceptualHash,
                 albumMusicBrainzId = rawSong.albumMusicBrainzId,
                 albumName = requireNotNull(rawSong.albumName) { "Invalid raw: No album name" },
                 albumSortName = rawSong.albumSortName,

app/src/main/java/org/oxycblt/auxio/music/device/DeviceMusicImpl.kt

@@ -20,6 +20,7 @@ package org.oxycblt.auxio.music.device
 
 import org.oxycblt.auxio.R
 import org.oxycblt.auxio.image.extractor.Cover
+import org.oxycblt.auxio.image.extractor.ParentCover
 import org.oxycblt.auxio.list.sort.Sort
 import org.oxycblt.auxio.music.Album
 import org.oxycblt.auxio.music.Artist
@@ -112,7 +113,8 @@ class SongImpl(
     override val genres: List<Genre>
         get() = _genres
 
-    override val cover = Cover("", requireNotNull(rawSong.mediaStoreId).toCoverUri(), uri)
+    override val cover =
+        Cover(rawSong.coverPerceptualHash, requireNotNull(rawSong.mediaStoreId).toCoverUri(), uri)
 
     /**
      * The [RawAlbum] instances collated by the [Song]. This can be used to group [Song]s into an
@@ -295,7 +297,7 @@ class AlbumImpl(
     override val releaseType = rawAlbum.releaseType ?: ReleaseType.Album(null)
     override val durationMs: Long
     override val dateAdded: Long
-    override val cover = grouping.raw.src.cover
+    override val cover: ParentCover
 
     private val _artists = mutableListOf<ArtistImpl>()
     override val artists: List<Artist>
@@ -339,6 +341,8 @@ class AlbumImpl(
         durationMs = totalDuration
         dateAdded = earliestDateAdded
 
+        cover = ParentCover.from(grouping.raw.src.cover, songs)
+
         hashCode = 31 * hashCode + rawAlbum.hashCode()
         hashCode = 31 * hashCode + nameFactory.hashCode()
         hashCode = 31 * hashCode + songs.hashCode()
@@ -421,12 +425,7 @@ class ArtistImpl(
     override val explicitAlbums: Set<Album>
     override val implicitAlbums: Set<Album>
     override val durationMs: Long?
-    override val cover =
+    override val cover: ParentCover
-        when (val src = grouping.raw.src) {
-            is AlbumImpl -> src.cover
-            is SongImpl -> src.cover
-            else -> error("Unexpected input music $src in $name ${src::class.simpleName}")
-        }
 
     override lateinit var genres: List<Genre>
 
@@ -459,6 +458,14 @@ class ArtistImpl(
         implicitAlbums = albums.filterNotTo(mutableSetOf()) { albumMap[it] == true }
         durationMs = songs.sumOf { it.durationMs }.positiveOrNull()
 
+        val singleCover =
+            when (val src = grouping.raw.src) {
+                is SongImpl -> src.cover
+                is AlbumImpl -> src.cover.single
+                else -> error("Unexpected input source $src in $name ${src::class.simpleName}")
+            }
+        cover = ParentCover.from(singleCover, songs)
+
         hashCode = 31 * hashCode + rawArtist.hashCode()
         hashCode = 31 * hashCode + nameFactory.hashCode()
         hashCode = 31 * hashCode + songs.hashCode()
@@ -536,7 +543,7 @@ class GenreImpl(
     override val songs: Set<Song>
     override val artists: Set<Artist>
     override val durationMs: Long
-    override val cover = grouping.raw.src.cover
+    override val cover: ParentCover
 
     private var hashCode = uid.hashCode()
 
@@ -554,6 +561,8 @@ class GenreImpl(
         artists = distinctArtists
         durationMs = totalDuration
 
+        cover = ParentCover.from(grouping.raw.src.cover, songs)
+
         hashCode = 31 * hashCode + rawGenre.hashCode()
         hashCode = 31 * hashCode + nameFactory.hashCode()
         hashCode = 31 * hashCode + songs.hashCode()

app/src/main/java/org/oxycblt/auxio/music/device/RawMusic.kt

@@ -67,6 +67,8 @@ data class RawSong(
     var subtitle: String? = null,
     /** @see Song.date */
     var date: Date? = null,
+    /** @see Song.cover */
+    var coverPerceptualHash: String? = null,
     /** @see RawAlbum.mediaStoreId */
     var albumMediaStoreId: Long? = null,
     /** @see RawAlbum.musicBrainzId */

app/src/main/java/org/oxycblt/auxio/music/metadata/TagWorker.kt

@@ -18,6 +18,7 @@
  
 package org.oxycblt.auxio.music.metadata
 
+import android.graphics.BitmapFactory
 import androidx.core.text.isDigitsOnly
 import androidx.media3.common.MediaItem
 import androidx.media3.exoplayer.MetadataRetriever
@@ -25,6 +26,8 @@ import androidx.media3.exoplayer.source.MediaSource
 import androidx.media3.exoplayer.source.TrackGroupArray
 import java.util.concurrent.Future
 import javax.inject.Inject
+import org.oxycblt.auxio.image.extractor.CoverExtractor
+import org.oxycblt.auxio.image.extractor.dHash
 import org.oxycblt.auxio.music.device.RawSong
 import org.oxycblt.auxio.music.fs.toAudioUri
 import org.oxycblt.auxio.music.info.Date
@@ -60,7 +63,10 @@ interface TagWorker {
 
 class TagWorkerFactoryImpl
 @Inject
-constructor(private val mediaSourceFactory: MediaSource.Factory) : TagWorker.Factory {
+constructor(
+    private val mediaSourceFactory: MediaSource.Factory,
+    private val coverExtractor: CoverExtractor
+) : TagWorker.Factory {
     override fun create(rawSong: RawSong): TagWorker =
         // Note that we do not leverage future callbacks. This is because errors in the
         // (highly fallible) extraction process will not bubble up to Indexer when a
@@ -70,12 +76,14 @@ constructor(private val mediaSourceFactory: MediaSource.Factory) : TagWorker.Fac
             MetadataRetriever.retrieveMetadata(
                 mediaSourceFactory,
                 MediaItem.fromUri(
-                    requireNotNull(rawSong.mediaStoreId) { "Invalid raw: No id" }.toAudioUri())))
+                    requireNotNull(rawSong.mediaStoreId) { "Invalid raw: No id" }.toAudioUri())),
+            coverExtractor)
 }
 
 private class TagWorkerImpl(
     private val rawSong: RawSong,
-    private val future: Future<TrackGroupArray>
+    private val future: Future<TrackGroupArray>,
+    private val coverExtractor: CoverExtractor
 ) : TagWorker {
     override fun poll(): RawSong? {
         if (!future.isDone) {
@@ -98,6 +106,11 @@ private class TagWorkerImpl(
             populateWithId3v2(textTags.id3v2)
             populateWithVorbis(textTags.vorbis)
 
+            val coverInputStream = coverExtractor.findCoverDataInMetadata(metadata)
+            val bitmap = coverInputStream?.use { BitmapFactory.decodeStream(it) }
+            rawSong.coverPerceptualHash = bitmap?.dHash()
+            bitmap?.recycle()
+
             // OPUS base gain interpretation code: This is likely not needed, as the media player
             // should be using the base gain already. Uncomment if that's not the case.
             // if (format.sampleMimeType == MimeTypes.AUDIO_OPUS

app/src/main/java/org/oxycblt/auxio/music/service/MediaItemTranslation.kt

@@ -74,7 +74,7 @@ fun Song.toMediaItem(context: Context, parent: MusicParent?): MediaItem {
             .setMediaType(MediaMetadata.MEDIA_TYPE_MUSIC)
             .setIsPlayable(true)
             .setIsBrowsable(false)
-            .setArtworkUri(album.cover.mediaStoreUri)
+            .setArtworkUri(album.cover.single.mediaStoreUri)
             .setExtras(
                 Bundle().apply {
                     putString("uid", mediaSessionUID.toString())
@@ -105,7 +105,7 @@ fun Album.toMediaItem(context: Context): MediaItem {
             .setMediaType(MediaMetadata.MEDIA_TYPE_ALBUM)
             .setIsPlayable(true)
             .setIsBrowsable(true)
-            .setArtworkUri(cover.mediaStoreUri)
+            .setArtworkUri(cover.single.mediaStoreUri)
             .setExtras(Bundle().apply { putString("uid", mediaSessionUID.toString()) })
             .build()
     return MediaItem.Builder()
@@ -136,7 +136,7 @@ fun Artist.toMediaItem(context: Context): MediaItem {
             .setIsPlayable(true)
             .setIsBrowsable(true)
             .setGenre(genres.resolveNames(context))
-            .setArtworkUri(cover.mediaStoreUri)
+            .setArtworkUri(cover.single.mediaStoreUri)
             .setExtras(Bundle().apply { putString("uid", mediaSessionUID.toString()) })
             .build()
     return MediaItem.Builder()
@@ -159,7 +159,7 @@ fun Genre.toMediaItem(context: Context): MediaItem {
             .setMediaType(MediaMetadata.MEDIA_TYPE_GENRE)
             .setIsPlayable(true)
             .setIsBrowsable(true)
-            .setArtworkUri(cover.mediaStoreUri)
+            .setArtworkUri(cover.single.mediaStoreUri)
             .setExtras(Bundle().apply { putString("uid", mediaSessionUID.toString()) })
             .build()
     return MediaItem.Builder()
@@ -182,7 +182,7 @@ fun Playlist.toMediaItem(context: Context): MediaItem {
             .setMediaType(MediaMetadata.MEDIA_TYPE_PLAYLIST)
             .setIsPlayable(true)
             .setIsBrowsable(true)
-            .setArtworkUri(cover?.mediaStoreUri)
+            .setArtworkUri(cover?.single?.mediaStoreUri)
             .setExtras(Bundle().apply { putString("uid", mediaSessionUID.toString()) })
             .build()
     return MediaItem.Builder()

app/src/main/java/org/oxycblt/auxio/music/user/PlaylistImpl.kt

@@ -18,6 +18,7 @@
  
 package org.oxycblt.auxio.music.user
 
+import org.oxycblt.auxio.image.extractor.ParentCover
 import org.oxycblt.auxio.music.Music
 import org.oxycblt.auxio.music.MusicType
 import org.oxycblt.auxio.music.Playlist
@@ -46,7 +47,7 @@ private constructor(
 
     override fun toString() = "Playlist(uid=$uid, name=$name)"
 
-    override val cover = songs.firstOrNull()?.cover
+    override val cover = songs.takeIf { it.isNotEmpty() }?.let { ParentCover.from(it.first(), it) }
 
     /**
      * Clone the data in this instance to a new [PlaylistImpl] with the given [name].