[tracker-miners: 1/3] tracker-extract-mp3.c: Extract AcoustID Fingerprint for mp3 files

[Sam Thursfield <sthursfield src gnome org>]

commit 36be4d9c0183483cb891fc02a1d794c4762d213c
Author: Sumaid Syed <sumaidsyed gmail com>
Date:   Fri Jul 5 14:57:29 2019 +0530

    tracker-extract-mp3.c: Extract AcoustID Fingerprint for mp3 files
    
    Tracker needs to store acoustid fingerprint (chromaprint) of songs,
    because calculating chromaprint is an expensive process.
    Tag Mappings: https://picard.musicbrainz.org/docs/mappings/
    
    https://gitlab.gnome.org/GNOME/tracker-miners/issues/72

 src/tracker-extract/tracker-extract-mp3.c | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)
---
diff --git a/src/tracker-extract/tracker-extract-mp3.c b/src/tracker-extract/tracker-extract-mp3.c
index bf2a0ed75..ec7ffaca2 100644
--- a/src/tracker-extract/tracker-extract-mp3.c
+++ b/src/tracker-extract/tracker-extract-mp3.c
@@ -95,6 +95,7 @@ typedef struct {
        gint track_count;
        gint set_number;
        gint set_count;
+       gchar *acoustid_fingerprint;
        gchar *mb_recording_id;
        gchar *mb_track_id;
        gchar *mb_release_id;
@@ -150,6 +151,7 @@ typedef enum {
 } id3v24frame;
 
 typedef enum {
+       ACOUSTID_FINGERPRINT,
        MB_TRACK_ID,
        MB_RELEASE_ID,
        MB_ARTIST_ID,
@@ -187,6 +189,7 @@ typedef struct {
        gint track_count;
        gint set_number;
        gint set_count;
+       const gchar *acoustid_fingerprint;
        const gchar *mb_recording_id;
        const gchar *mb_track_id;
        const gchar *mb_release_id;
@@ -274,6 +277,7 @@ static const struct {
        const char *name;
        id3txxxtype txxxtype;
 } id3_txxxtypes[] = {
+       { "Acoustid Fingerprint", ACOUSTID_FINGERPRINT },
        { "MusicBrainz Release Track Id", MB_TRACK_ID },
        { "MusicBrainz Album Id", MB_RELEASE_ID },
        { "MusicBrainz Artist Id", MB_ARTIST_ID },
@@ -572,6 +576,7 @@ id3v2tag_free (id3v2tag *tags)
        g_free (tags->title1);
        g_free (tags->title2);
        g_free (tags->title3);
+       g_free (tags->acoustid_fingerprint);
        g_free (tags->mb_recording_id);
        g_free (tags->mb_track_id);
        g_free (tags->mb_release_id);
@@ -1398,6 +1403,9 @@ extract_txxx_tags (id3v2tag *tag, const gchar *data, guint pos, size_t csize, id
                return;
        }
        switch (txxxtype) {
+       case ACOUSTID_FINGERPRINT:
+               tag->acoustid_fingerprint = value;
+               break;
        case MB_TRACK_ID:
                tag->mb_track_id = value;
                break;
@@ -2640,6 +2648,9 @@ tracker_extract_get_metadata (TrackerExtractInfo *info)
                                                md.id3v23.encoded_by,
                                                md.id3v22.encoded_by);
 
+       md.acoustid_fingerprint = tracker_coalesce_strip (2, md.id3v24.acoustid_fingerprint,
+                                                         md.id3v23.acoustid_fingerprint);
+
        md.mb_recording_id = tracker_coalesce_strip (2, md.id3v24.mb_recording_id,
                                                     md.id3v23.mb_recording_id);
 
@@ -2802,6 +2813,20 @@ tracker_extract_get_metadata (TrackerExtractInfo *info)
                tracker_resource_set_string (main_resource, "nmm:mbTrackID", md.mb_track_id);
        }
 
+       if (md.acoustid_fingerprint) {
+               TrackerResource *hash_resource;
+
+               hash_resource = tracker_resource_new (NULL);
+               tracker_resource_set_uri (hash_resource, "rdf:type", "nfo:FileHash");
+
+               tracker_resource_set_string (hash_resource, "nfo:hashValue", md.acoustid_fingerprint);
+               tracker_resource_set_string (hash_resource, "nfo:hashAlgorithm", "chromaprint");
+
+               tracker_resource_set_relation (main_resource, "nfo:hasHash", hash_resource);
+
+               g_object_unref (hash_resource);
+       }
+
        /* Get mp3 stream info */
        parsed = mp3_parse (buffer, buffer_size, audio_offset, uri, main_resource, &md);
        g_clear_object (&md.performer);