avutil/frame: add AV_FRAME_SIDE_DATA_FLAG_NEW_REF

The flag is documented but did not exist. So introduce it as it can be
useful.

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

doc/APIchanges

@@ -2,6 +2,9 @@ The last version increases of all libraries were on 2024-03-07
 
 API changes, most recent first:
 
+2025-01-05 - xxxxxxxxxx - lavc 59.55.100 - frame.h
+  Add AV_FRAME_SIDE_DATA_FLAG_NEW_REF.
+
 2025-01-05 - xxxxxxxxxx - lavc 61.31.100 - avcodec.h
   Deprecate AVCodecContext->properties.
 

libavutil/frame.c

@@ -868,21 +868,20 @@ AVFrameSideData *av_frame_side_data_add(AVFrameSideData ***sd, int *nb_sd,
     AVFrameSideData *sd_dst  = NULL;
     AVBufferRef *buf = *pbuf;
 
+    if ((flags & AV_FRAME_SIDE_DATA_FLAG_NEW_REF) && !(buf = av_buffer_ref(*pbuf)))
+        return NULL;
     if (flags & AV_FRAME_SIDE_DATA_FLAG_UNIQUE)
         remove_side_data(sd, nb_sd, type);
     if ((!desc || !(desc->props & AV_SIDE_DATA_PROP_MULTI)) &&
         (sd_dst = (AVFrameSideData *)av_frame_side_data_get(*sd, *nb_sd, type))) {
         sd_dst = replace_side_data_from_buf(sd_dst, buf, flags);
-        if (sd_dst)
-            *pbuf = NULL;
-        return sd_dst;
-    }
-
-    sd_dst = add_side_data_from_buf(sd, nb_sd, type, buf);
-    if (!sd_dst)
-        return NULL;
+    } else
+        sd_dst = add_side_data_from_buf(sd, nb_sd, type, buf);
 
-    *pbuf = NULL;
+    if (sd_dst && !(flags & AV_FRAME_SIDE_DATA_FLAG_NEW_REF))
+        *pbuf = NULL;
+    else if (!sd_dst && (flags & AV_FRAME_SIDE_DATA_FLAG_NEW_REF))
+        av_buffer_unref(&buf);
     return sd_dst;
 }
 

libavutil/frame.h

@@ -1082,6 +1082,11 @@ void av_frame_side_data_free(AVFrameSideData ***sd, int *nb_sd);
  * Applies only for side data types without the AV_SIDE_DATA_PROP_MULTI prop.
  */
 #define AV_FRAME_SIDE_DATA_FLAG_REPLACE (1 << 1)
+/**
+ * Create a new reference to the passed in buffer instead of taking ownership
+ * of it.
+ */
+#define AV_FRAME_SIDE_DATA_FLAG_NEW_REF (1 << 2)
 
 /**
  * Add new side data entry to an array.

libavutil/version.h

@@ -79,8 +79,8 @@
  */
 
 #define LIBAVUTIL_VERSION_MAJOR  59
-#define LIBAVUTIL_VERSION_MINOR  54
-#define LIBAVUTIL_VERSION_MICRO 101
+#define LIBAVUTIL_VERSION_MINOR  55
+#define LIBAVUTIL_VERSION_MICRO 100
 
 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \
                                                LIBAVUTIL_VERSION_MINOR, \