diff --git a/libavformat/avformat.c b/libavformat/avformat.c
index d0cda8f3b4..f0009eaae5 100644
--- a/libavformat/avformat.c
+++ b/libavformat/avformat.c
@@ -84,7 +84,14 @@ void ff_free_stream_group(AVStreamGroup **pstg)
     if (!stg)
         return;
 
+#if FF_API_STREAM_GROUP_ENTRIES
+FF_DISABLE_DEPRECATION_WARNINGS
     av_freep(&stg->streams);
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
+    for (int i = 0; i < stg->nb_entries; i++)
+        av_freep(&stg->entries[i]);
+    av_freep(&stg->entries);
     av_dict_free(&stg->metadata);
     av_freep(&stg->priv_data);
     switch (stg->type) {
@@ -642,8 +649,10 @@ static int match_stream_specifier(const AVFormatContext *s, const AVStream *st,
                 }
                 if (group_idx < 0 || group_idx >= s->nb_stream_groups)
                     return AVERROR(EINVAL);
-                for (unsigned j = 0; j < s->stream_groups[group_idx]->nb_streams; j++) {
-                    if (st->index == s->stream_groups[group_idx]->streams[j]->index) {
+                for (unsigned j = 0; j < s->stream_groups[group_idx]->nb_entries; j++) {
+                    if (s->stream_groups[group_idx]->entries[j]->type != AV_STREAM_GROUP_ENTRY_STREAM)
+                        continue;
+                    if (st->index == s->stream_groups[group_idx]->entries[j]->stream->index) {
                         found = 1;
                         if (g)
                             *g = s->stream_groups[group_idx];
@@ -772,9 +781,11 @@ int avformat_match_stream_specifier(AVFormatContext *s, AVStream *st,
         return (index == st->index);
 
     /* If we requested a matching stream index, we have to ensure st is that. */
-    nb_streams = g ? g->nb_streams : (p ? p->nb_stream_indexes : s->nb_streams);
+    nb_streams = g ? g->nb_entries : (p ? p->nb_stream_indexes : s->nb_streams);
     for (int i = 0; i < nb_streams && index >= 0; i++) {
-        unsigned idx = g ? g->streams[i]->index : (p ? p->stream_index[i] : i);
+        if (g && g->entries[i]->type != AV_STREAM_GROUP_ENTRY_STREAM)
+            continue;
+        unsigned idx = g ? g->entries[i]->stream->index : (p ? p->stream_index[i] : i);
         const AVStream *candidate = s->streams[idx];
         ret = match_stream_specifier(s, candidate, spec, NULL, NULL, NULL);
         if (ret < 0)
diff --git a/libavformat/avformat.h b/libavformat/avformat.h
index 07ed2764cd..6279150609 100644
--- a/libavformat/avformat.h
+++ b/libavformat/avformat.h
@@ -1162,6 +1162,19 @@ enum AVStreamGroupParamsType {
 struct AVIAMFAudioElement;
 struct AVIAMFMixPresentation;
 
+enum AVStreamGroupEntryType {
+    AV_STREAM_GROUP_ENTRY_STREAM,
+    AV_STREAM_GROUP_ENTRY_STREAM_GROUP,
+};
+
+typedef struct AVStreamGroupEntry {
+    enum AVStreamGroupEntryType type;
+    union {
+        AVStream *stream;
+        struct AVStreamGroup *stream_group;
+    };
+} AVStreamGroupEntry;
+
 typedef struct AVStreamGroup {
     /**
      * A class for @ref avoptions. Set by avformat_stream_group_create().
@@ -1219,11 +1232,15 @@ typedef struct AVStreamGroup {
      */
     AVDictionary *metadata;
 
+#if FF_API_STREAM_GROUP_ENTRIES
     /**
      * Number of elements in AVStreamGroup.streams.
      *
-     * Set by avformat_stream_group_add_stream() must not be modified by any other code.
+     * Set by avformat_stream_group_add_stream(), must not be modified by any other code.
+     *
+     * @deprecated Use AVStreamGroup.nb_entries.
      */
+    attribute_deprecated
     unsigned int nb_streams;
 
     /**
@@ -1236,8 +1253,12 @@ typedef struct AVStreamGroup {
      * - muxing: entries are created by the user before avformat_write_header().
      *
      * Freed by libavformat in avformat_free_context().
+     *
+     * @deprecated Use AVStreamGroup.entries.
      */
+    attribute_deprecated
     AVStream **streams;
+#endif
 
     /**
      * Stream group disposition - a combination of AV_DISPOSITION_* flags.
@@ -1248,6 +1269,27 @@ typedef struct AVStreamGroup {
      * - muxing: may be set by the caller before avformat_write_header().
      */
     int disposition;
+
+    /**
+     * Number of elements in AVStreamGroup.entries.
+     *
+     * Set by avformat_stream_group_add_stream() or avformat_stream_group_add_stream_group(),
+     * must not be modified by any other code.
+     */
+    unsigned int nb_entries;
+
+    /**
+     * A list of streams or child groups in the group. New entries are created with
+     * or avformat_stream_group_add_stream() or avformat_stream_group_add_stream_group().
+     *
+     * - demuxing: entries are created by libavformat on group creation.
+     *             If AVFMTCTX_NOHEADER is set in ctx_flags, then new entries may also
+     *             appear in av_read_frame().
+     * - muxing: entries are created by the user before avformat_write_header().
+     *
+     * Freed by libavformat in avformat_free_context().
+     */
+    AVStreamGroupEntry **entries;
 } AVStreamGroup;
 
 struct AVCodecParserContext *av_stream_get_parser(const AVStream *s);
@@ -1414,7 +1456,8 @@ typedef struct AVFormatContext {
     unsigned int nb_stream_groups;
     /**
      * A list of all stream groups in the file. New groups are created with
-     * avformat_stream_group_create(), and filled with avformat_stream_group_add_stream().
+     * avformat_stream_group_create(), and filled with avformat_stream_group_add_stream()
+     * and avformat_stream_group_add_stream_group.
      *
      * - demuxing: groups may be created by libavformat in avformat_open_input().
      *             If AVFMTCTX_NOHEADER is set in ctx_flags, then new groups may also
@@ -2116,11 +2159,13 @@ const char *avformat_stream_group_name(enum AVStreamGroupParamsType type);
  * by avformat_stream_group_create().
  *
  * New streams can be added to the group with avformat_stream_group_add_stream().
+ * Child groups can be added to the group with avformat_stream_group_add_stream_group().
  *
  * @param s media file handle
  *
  * @return newly created group or NULL on error.
- * @see avformat_new_stream, avformat_stream_group_add_stream.
+ * @see avformat_new_stream.
+ * @see avformat_stream_group_add_stream, avformat_stream_group_add_stream_group.
  */
 AVStreamGroup *avformat_stream_group_create(AVFormatContext *s,
                                             enum AVStreamGroupParamsType type,
@@ -2170,6 +2215,31 @@ AVStream *avformat_new_stream(AVFormatContext *s, const struct AVCodec *c);
  */
 int avformat_stream_group_add_stream(AVStreamGroup *stg, AVStream *st);
 
+/**
+ * Add an already allocated stream group to another stream group.
+ *
+ * When demuxing, it may be called by the demuxer in read_header(). If the
+ * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also
+ * be called in read_packet().
+ *
+ * When muxing, may be called by the user before avformat_write_header() after
+ * having allocated a both the parent and child groups with
+ * avformat_stream_group_create().
+ *
+ * User is required to call avformat_free_context() to clean up the allocation
+ * by avformat_stream_group_add_stream_group().
+ *
+ * @param stg stream group belonging to a media file.
+ * @param group stream group in the media file to add to the group.
+ *
+ * @retval 0                 success
+ * @retval AVERROR(EEXIST)   the stream group was already in the group
+ * @retval "another negative error code" legitimate errors
+ *
+ * @see avformat_stream_group_create.
+ */
+int avformat_stream_group_add_stream_group(AVStreamGroup *stg, AVStreamGroup *group);
+
 AVProgram *av_new_program(AVFormatContext *s, int id);
 
 
diff --git a/libavformat/options.c b/libavformat/options.c
index 042fe494cf..e1c094f538 100644
--- a/libavformat/options.c
+++ b/libavformat/options.c
@@ -547,13 +547,37 @@ fail:
 
 static int stream_group_add_stream(AVStreamGroup *stg, AVStream *st)
 {
+#if FF_API_STREAM_GROUP_ENTRIES
+FF_DISABLE_DEPRECATION_WARNINGS
     AVStream **streams = av_realloc_array(stg->streams, stg->nb_streams + 1,
                                           sizeof(*stg->streams));
     if (!streams)
         return AVERROR(ENOMEM);
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
 
+    AVStreamGroupEntry **entries = av_realloc_array(stg->entries, stg->nb_entries + 1,
+                                                    sizeof(*stg->entries));
+    if (!entries)
+        return AVERROR(ENOMEM);
+
+    stg->entries = entries;
+    stg->entries[stg->nb_entries] = av_mallocz(sizeof(*stg->entries[stg->nb_entries]));
+    if (!stg->entries[stg->nb_entries])
+        return AVERROR(ENOMEM);
+
+    stg->entries[stg->nb_entries]->type = AV_STREAM_GROUP_ENTRY_STREAM;
+    stg->entries[stg->nb_entries++]->stream = st;
+
+#if FF_API_STREAM_GROUP_ENTRIES
+FF_DISABLE_DEPRECATION_WARNINGS
     stg->streams = streams;
-    stg->streams[stg->nb_streams++] = st;
+    if (stg->nb_streams == (stg->nb_entries - 1))
+        stg->streams[stg->nb_streams++] = st;
+    else
+        stg->nb_streams = 0;
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
 
     return 0;
 }
@@ -566,13 +590,59 @@ int avformat_stream_group_add_stream(AVStreamGroup *stg, AVStream *st)
     if (stgi->fmtctx != sti->fmtctx)
         return AVERROR(EINVAL);
 
-    for (int i = 0; i < stg->nb_streams; i++)
-        if (stg->streams[i]->index == st->index)
+    for (int i = 0; i < stg->nb_entries; i++) {
+        const AVStreamGroupEntry *entry = stg->entries[i];
+        if (entry->type != AV_STREAM_GROUP_ENTRY_STREAM)
+            continue;
+        if (entry->stream->index == st->index)
             return AVERROR(EEXIST);
+    }
 
     return stream_group_add_stream(stg, st);
 }
 
+static int stream_group_add_stream_group(AVStreamGroup *stg, AVStreamGroup *group)
+{
+    AVStreamGroupEntry **entries = av_realloc_array(stg->entries, stg->nb_entries + 1,
+                                                    sizeof(*stg->entries));
+    if (!entries)
+        return AVERROR(ENOMEM);
+
+    stg->entries = entries;
+    stg->entries[stg->nb_entries] = av_mallocz(sizeof(*stg->entries[stg->nb_entries]));
+    if (!stg->entries[stg->nb_entries])
+        return AVERROR(ENOMEM);
+
+    stg->entries[stg->nb_entries]->type = AV_STREAM_GROUP_ENTRY_STREAM_GROUP;
+    stg->entries[stg->nb_entries++]->stream_group = group;
+#if FF_API_STREAM_GROUP_ENTRIES
+FF_DISABLE_DEPRECATION_WARNINGS
+    stg->nb_streams = 0;
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
+
+    return 0;
+}
+
+int avformat_stream_group_add_stream_group(AVStreamGroup *stg, AVStreamGroup *group)
+{
+    const FFStreamGroup *stgi = cffstreamgroup(stg);
+    const FFStreamGroup *groupi = cffstreamgroup(group);
+
+    if (stgi->fmtctx != groupi->fmtctx)
+        return AVERROR(EINVAL);
+
+    for (int i = 0; i < stg->nb_entries; i++) {
+        const AVStreamGroupEntry *entry = stg->entries[i];
+        if (entry->type != AV_STREAM_GROUP_ENTRY_STREAM_GROUP)
+            continue;
+        if (entry->stream_group->index == group->index)
+            return AVERROR(EEXIST);
+    }
+
+    return stream_group_add_stream_group(stg, group);
+}
+
 static int option_is_disposition(const AVOption *opt)
 {
     return opt->type == AV_OPT_TYPE_CONST &&
diff --git a/libavformat/version_major.h b/libavformat/version_major.h
index f0eaa170b4..9a7955d9e4 100644
--- a/libavformat/version_major.h
+++ b/libavformat/version_major.h
@@ -49,6 +49,8 @@
 
 #define FF_API_OLD_ID3V2_COMMENT        (LIBAVFORMAT_VERSION_MAJOR < 64)
 
+#define FF_API_STREAM_GROUP_ENTRIES     (LIBAVFORMAT_VERSION_MAJOR < 64)
+
 #define FF_API_R_FRAME_RATE            1
 
 #endif /* AVFORMAT_VERSION_MAJOR_H */