avformat: introduce AVStreamGroup

Signed-off-by: James Almer <jamrial@gmail.com>

1 files changed, 86 insertions, 5 deletions

diff --git a/libavformat/avformat.c b/libavformat/avformat.c
index 5b8bb7879e..7e747c43d5 100644
--- a/libavformat/avformat.c
+++ b/libavformat/avformat.c
@@ -24,6 +24,7 @@
 #include "libavutil/avstring.h"
 #include "libavutil/channel_layout.h"
 #include "libavutil/frame.h"
+#include "libavutil/iamf.h"
 #include "libavutil/intreadwrite.h"
 #include "libavutil/mem.h"
 #include "libavutil/opt.h"
@@ -80,6 +81,32 @@ FF_ENABLE_DEPRECATION_WARNINGS
     av_freep(pst);
 }
 
+void ff_free_stream_group(AVStreamGroup **pstg)
+{
+    AVStreamGroup *stg = *pstg;
+
+    if (!stg)
+        return;
+
+    av_freep(&stg->streams);
+    av_dict_free(&stg->metadata);
+    av_freep(&stg->priv_data);
+    switch (stg->type) {
+    case AV_STREAM_GROUP_PARAMS_IAMF_AUDIO_ELEMENT: {
+        av_iamf_audio_element_free(&stg->params.iamf_audio_element);
+        break;
+    }
+    case AV_STREAM_GROUP_PARAMS_IAMF_MIX_PRESENTATION: {
+        av_iamf_mix_presentation_free(&stg->params.iamf_mix_presentation);
+        break;
+    }
+    default:
+        break;
+    }
+
+    av_freep(pstg);
+}
+
 void ff_remove_stream(AVFormatContext *s, AVStream *st)
 {
     av_assert0(s->nb_streams>0);
@@ -88,6 +115,14 @@ void ff_remove_stream(AVFormatContext *s, AVStream *st)
     ff_free_stream(&s->streams[ --s->nb_streams ]);
 }
 
+void ff_remove_stream_group(AVFormatContext *s, AVStreamGroup *stg)
+{
+    av_assert0(s->nb_stream_groups > 0);
+    av_assert0(s->stream_groups[ s->nb_stream_groups - 1 ] == stg);
+
+    ff_free_stream_group(&s->stream_groups[ --s->nb_stream_groups ]);
+}
+
 /* XXX: suppress the packet queue */
 void ff_flush_packet_queue(AVFormatContext *s)
 {
@@ -118,6 +153,9 @@ void avformat_free_context(AVFormatContext *s)
 
     for (unsigned i = 0; i < s->nb_streams; i++)
         ff_free_stream(&s->streams[i]);
+    for (unsigned i = 0; i < s->nb_stream_groups; i++)
+        ff_free_stream_group(&s->stream_groups[i]);
+    s->nb_stream_groups = 0;
     s->nb_streams = 0;
 
     for (unsigned i = 0; i < s->nb_programs; i++) {
@@ -139,6 +177,7 @@ void avformat_free_context(AVFormatContext *s)
     av_packet_free(&si->pkt);
     av_packet_free(&si->parse_pkt);
     av_freep(&s->streams);
+    av_freep(&s->stream_groups);
     ff_flush_packet_queue(s);
     av_freep(&s->url);
     av_free(s);
@@ -464,7 +503,7 @@ int av_find_best_stream(AVFormatContext *ic, enum AVMediaType type,
  */
 static int match_stream_specifier(const AVFormatContext *s, const AVStream *st,
                                   const char *spec, const char **indexptr,
-                                  const AVProgram **p)
+                                  const AVStreamGroup **g, const AVProgram **p)
 {
     int match = 1;                      /* Stores if the specifier matches so far. */
     while (*spec) {
@@ -493,6 +532,46 @@ static int match_stream_specifier(const AVFormatContext *s, const AVStream *st,
                 match = 0;
             if (nopic && (st->disposition & AV_DISPOSITION_ATTACHED_PIC))
                 match = 0;
+        } else if (*spec == 'g' && *(spec + 1) == ':') {
+            int64_t group_idx = -1, group_id = -1;
+            int found = 0;
+            char *endptr;
+            spec += 2;
+            if (*spec == '#' || (*spec == 'i' && *(spec + 1) == ':')) {
+                spec += 1 + (*spec == 'i');
+                group_id = strtol(spec, &endptr, 0);
+                if (spec == endptr || (*endptr && *endptr++ != ':'))
+                    return AVERROR(EINVAL);
+                spec = endptr;
+            } else {
+                group_idx = strtol(spec, &endptr, 0);
+                /* Disallow empty id and make sure that if we are not at the end, then another specifier must follow. */
+                if (spec == endptr || (*endptr && *endptr++ != ':'))
+                    return AVERROR(EINVAL);
+                spec = endptr;
+            }
+            if (match) {
+                if (group_id > 0) {
+                    for (unsigned i = 0; i < s->nb_stream_groups; i++) {
+                        if (group_id == s->stream_groups[i]->id) {
+                            group_idx = i;
+                            break;
+                        }
+                    }
+                }
+                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) {
+                        found = 1;
+                        if (g)
+                            *g = s->stream_groups[group_idx];
+                        break;
+                    }
+                }
+            }
+            if (!found)
+                match = 0;
         } else if (*spec == 'p' && *(spec + 1) == ':') {
             int prog_id;
             int found = 0;
@@ -591,10 +670,11 @@ int avformat_match_stream_specifier(AVFormatContext *s, AVStream *st,
     int ret, index;
     char *endptr;
     const char *indexptr = NULL;
+    const AVStreamGroup *g = NULL;
     const AVProgram *p = NULL;
     int nb_streams;
 
-    ret = match_stream_specifier(s, st, spec, &indexptr, &p);
+    ret = match_stream_specifier(s, st, spec, &indexptr, &g, &p);
     if (ret < 0)
         goto error;
 
@@ -612,10 +692,11 @@ 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 = p ? p->nb_stream_indexes : s->nb_streams;
+    nb_streams = g ? g->nb_streams : (p ? p->nb_stream_indexes : s->nb_streams);
     for (int i = 0; i < nb_streams && index >= 0; i++) {
-        const AVStream *candidate = s->streams[p ? p->stream_index[i] : i];
-        ret = match_stream_specifier(s, candidate, spec, NULL, NULL);
+        unsigned idx = g ? g->streams[i]->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)
             goto error;
         if (ret > 0 && index-- == 0 && st == candidate)