avutil/frame: add helper for adding side data to array

Additionally, add an API test to check that the no-duplicates
addition works after duplicates have been inserted.

1 files changed, 103 insertions, 0 deletions

diff --git a/libavutil/tests/side_data_array.c b/libavutil/tests/side_data_array.c
new file mode 100644
index 0000000000..793a62c009
--- /dev/null
+++ b/libavutil/tests/side_data_array.c
@@ -0,0 +1,103 @@
+/*
+ * Copyright (c) 2023 Jan Ekström <jeebjp@gmail.com>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdio.h>
+#include "libavutil/frame.c"
+#include "libavutil/mastering_display_metadata.h"
+
+static void print_clls(const AVFrameSideData **sd, const int nb_sd)
+{
+    for (int i = 0; i < nb_sd; i++) {
+        const AVFrameSideData *entry = sd[i];
+
+        printf("sd %d, %s",
+               i, av_frame_side_data_name(entry->type));
+
+        if (entry->type != AV_FRAME_DATA_CONTENT_LIGHT_LEVEL) {
+            putchar('\n');
+            continue;
+        }
+
+        printf(": MaxCLL: %u\n",
+               ((AVContentLightMetadata *)entry->data)->MaxCLL);
+    }
+}
+
+typedef struct FrameSideDataSet {
+    AVFrameSideData **sd;
+    int            nb_sd;
+} FrameSideDataSet;
+
+int main(void)
+{
+    FrameSideDataSet set = { 0 };
+
+    av_assert0(
+        av_frame_side_data_new(&set.sd, &set.nb_sd,
+                               AV_FRAME_DATA_AMBIENT_VIEWING_ENVIRONMENT,
+                               0, 0));
+
+    // test entries in the middle
+    for (int value = 1; value < 4; value++) {
+        AVFrameSideData *sd = av_frame_side_data_new(
+            &set.sd, &set.nb_sd, AV_FRAME_DATA_CONTENT_LIGHT_LEVEL,
+            sizeof(AVContentLightMetadata), 0);
+
+        av_assert0(sd);
+
+        ((AVContentLightMetadata *)sd->data)->MaxCLL = value;
+    }
+
+    av_assert0(
+        av_frame_side_data_new(
+            &set.sd, &set.nb_sd, AV_FRAME_DATA_SPHERICAL, 0, 0));
+
+    // test entries at the end
+    for (int value = 1; value < 4; value++) {
+        AVFrameSideData *sd = av_frame_side_data_new(
+            &set.sd, &set.nb_sd, AV_FRAME_DATA_CONTENT_LIGHT_LEVEL,
+            sizeof(AVContentLightMetadata), 0);
+
+        av_assert0(sd);
+
+        ((AVContentLightMetadata *)sd->data)->MaxCLL = value + 3;
+    }
+
+    puts("Initial addition results with duplicates:");
+    print_clls((const AVFrameSideData **)set.sd, set.nb_sd);
+
+    {
+        AVFrameSideData *sd = av_frame_side_data_new(
+            &set.sd, &set.nb_sd, AV_FRAME_DATA_CONTENT_LIGHT_LEVEL,
+            sizeof(AVContentLightMetadata),
+            AV_FRAME_SIDE_DATA_FLAG_UNIQUE);
+
+        av_assert0(sd);
+
+        ((AVContentLightMetadata *)sd->data)->MaxCLL = 1337;
+    }
+
+    puts("\nFinal state after a single 'no-duplicates' addition:");
+    print_clls((const AVFrameSideData **)set.sd, set.nb_sd);
+
+    av_frame_side_data_free(&set.sd, &set.nb_sd);
+
+    return 0;
+}