diff --git a/libavformat/matroska.c b/libavformat/matroska.c
index d2d07a8eca..652e4d0b03 100644
--- a/libavformat/matroska.c
+++ b/libavformat/matroska.c
@@ -24,6 +24,7 @@
 const CodecTags ff_mkv_codec_tags[]={
     {"A_AAC"            , AV_CODEC_ID_AAC},
     {"A_AC3"            , AV_CODEC_ID_AC3},
+    {"A_ALAC"           , AV_CODEC_ID_ALAC},
     {"A_DTS"            , AV_CODEC_ID_DTS},
     {"A_EAC3"           , AV_CODEC_ID_EAC3},
     {"A_FLAC"           , AV_CODEC_ID_FLAC},
diff --git a/libavformat/matroskadec.c b/libavformat/matroskadec.c
index ff2a6c29dc..69a8c7f06e 100644
--- a/libavformat/matroskadec.c
+++ b/libavformat/matroskadec.c
@@ -1528,6 +1528,19 @@ static int matroska_read_header(AVFormatContext *s)
                 extradata_size = 5;
             } else
                 extradata_size = 2;
+        } else if (codec_id == AV_CODEC_ID_ALAC && track->codec_priv.size) {
+            /* Only ALAC's magic cookie is stored in Matroska's track headers.
+               Create the "atom size", "tag", and "tag version" fields the
+               decoder expects manually. */
+            extradata_size = 12 + track->codec_priv.size;
+            extradata = av_mallocz(extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
+            if (extradata == NULL)
+                return AVERROR(ENOMEM);
+            AV_WB32(extradata, extradata_size);
+            memcpy(&extradata[4], "alac", 4);
+            AV_WB32(&extradata[8], 0);
+            memcpy(&extradata[12], track->codec_priv.data,
+                                   track->codec_priv.size);
         } else if (codec_id == AV_CODEC_ID_TTA) {
             extradata_size = 30;
             extradata = av_mallocz(extradata_size);
diff --git a/libavformat/matroskaenc.c b/libavformat/matroskaenc.c
index 9d9c223dbb..521f6b5c1a 100644
--- a/libavformat/matroskaenc.c
+++ b/libavformat/matroskaenc.c
@@ -475,6 +475,16 @@ static int mkv_write_codecprivate(AVFormatContext *s, AVIOContext *pb, AVCodecCo
             ret = ff_flac_write_header(dyn_cp, codec, 1);
         else if (codec->codec_id == AV_CODEC_ID_H264)
             ret = ff_isom_write_avcc(dyn_cp, codec->extradata, codec->extradata_size);
+        else if (codec->codec_id == AV_CODEC_ID_ALAC) {
+            if (codec->extradata_size < 36) {
+                av_log(s, AV_LOG_ERROR,
+                       "Invalid extradata found, ALAC expects a 36-byte "
+                       "QuickTime atom.");
+                ret = AVERROR_INVALIDDATA;
+            } else
+                avio_write(dyn_cp, codec->extradata + 12,
+                                   codec->extradata_size - 12);
+        }
         else if (codec->extradata_size)
             avio_write(dyn_cp, codec->extradata, codec->extradata_size);
     } else if (codec->codec_type == AVMEDIA_TYPE_VIDEO) {