From 460beb948ceddeb86bd2b3b17335176adcaa7223 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jan=20Ekstr=C3=B6m?= <jan.ekstrom@24i.com>
Date: Wed, 24 Feb 2021 14:19:28 +0200
Subject: [PATCH] avformat/ttml: split TTML paragraph based or not check into
 header
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

This way it can be re-utilized in movenc.

Signed-off-by: Jan Ekström <jan.ekstrom@24i.com>
---
 libavformat/ttmlenc.c |  9 ++-------
 libavformat/ttmlenc.h | 39 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+), 7 deletions(-)
 create mode 100644 libavformat/ttmlenc.h

diff --git a/libavformat/ttmlenc.c b/libavformat/ttmlenc.c
index 8546d35196..896fc81958 100644
--- a/libavformat/ttmlenc.c
+++ b/libavformat/ttmlenc.c
@@ -30,6 +30,7 @@
 #include "libavutil/avstring.h"
 #include "avformat.h"
 #include "internal.h"
+#include "ttmlenc.h"
 #include "libavcodec/ttmlenc.h"
 #include "libavutil/internal.h"
 
@@ -138,13 +139,7 @@ static int ttml_write_header(AVFormatContext *ctx)
                                               0);
         const char *printed_lang = (lang && lang->value) ? lang->value : "";
 
-        // Not perfect, but decide whether the packet is a document or not
-        // by the existence of the lavc ttmlenc extradata.
-        ttml_ctx->input_type = (st->codecpar->extradata &&
-                                st->codecpar->extradata_size >= TTMLENC_EXTRADATA_SIGNATURE_SIZE &&
-                                !memcmp(st->codecpar->extradata,
-                                        TTMLENC_EXTRADATA_SIGNATURE,
-                                        TTMLENC_EXTRADATA_SIGNATURE_SIZE)) ?
+        ttml_ctx->input_type = ff_is_ttml_stream_paragraph_based(st->codecpar) ?
                                PACKET_TYPE_PARAGRAPH :
                                PACKET_TYPE_DOCUMENT;
 
diff --git a/libavformat/ttmlenc.h b/libavformat/ttmlenc.h
new file mode 100644
index 0000000000..5a6954f3c1
--- /dev/null
+++ b/libavformat/ttmlenc.h
@@ -0,0 +1,39 @@
+/*
+ * Generic TTML helpers
+ * Copyright (c) 2021 24i
+ *
+ * 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
+ */
+
+#ifndef AVFORMAT_TTMLENC_H
+#define AVFORMAT_TTMLENC_H
+
+#include "libavcodec/codec_par.h"
+#include "libavcodec/ttmlenc.h"
+
+static inline unsigned int ff_is_ttml_stream_paragraph_based(const AVCodecParameters *codecpar)
+{
+    // Not perfect, but decide whether the packet is a document or not
+    // by the existence of the lavc ttmlenc extradata.
+    return (codecpar->extradata &&
+            codecpar->extradata_size >= TTMLENC_EXTRADATA_SIGNATURE_SIZE &&
+            !memcmp(codecpar->extradata,
+                    TTMLENC_EXTRADATA_SIGNATURE,
+                    TTMLENC_EXTRADATA_SIGNATURE_SIZE));
+}
+
+#endif /* AVFORMAT_TTMLENC_H */