avutil: add an API to handle 3D Reference Displays Information

As defined in section G.14.3.2.3 of ITU-T H.265, it's required for proper
signaling of MV-HEVC.

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

1 files changed, 51 insertions, 0 deletions

diff --git a/libavutil/tdrdi.c b/libavutil/tdrdi.c
new file mode 100644
index 0000000000..26192a1d2f
--- /dev/null
+++ b/libavutil/tdrdi.c
@@ -0,0 +1,51 @@
+/*
+ * 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 <stddef.h>
+#include <stdint.h>
+
+#include "mem.h"
+#include "tdrdi.h"
+
+AV3DReferenceDisplaysInfo *av_tdrdi_alloc(unsigned int nb_displays, size_t *out_size)
+{
+    struct TestStruct {
+        AV3DReferenceDisplaysInfo p;
+        AV3DReferenceDisplay      b;
+    };
+    const size_t entries_offset = offsetof(struct TestStruct, b);
+    size_t size = entries_offset;
+    AV3DReferenceDisplaysInfo *tdrdi;
+
+    if (nb_displays > (SIZE_MAX - size) / sizeof(AV3DReferenceDisplay))
+        return NULL;
+    size += sizeof(AV3DReferenceDisplay) * nb_displays;
+
+    tdrdi = av_mallocz(size);
+    if (!tdrdi)
+        return NULL;
+
+    tdrdi->num_ref_displays = nb_displays;
+    tdrdi->entry_size       = sizeof(AV3DReferenceDisplay);
+    tdrdi->entries_offset   = entries_offset;
+
+    if (out_size)
+        *out_size = size;
+
+    return tdrdi;
+}