avcodec/avs2: add AVS2 related definitions

Replace magic numbers by enum values.

Signed-off-by: Zhao Zhili <zhilizhao@tencent.com>

2 files changed, 42 insertions, 5 deletions

diff --git a/libavcodec/avs2.h b/libavcodec/avs2.h
new file mode 100644
index 0000000000..7b66f51998
--- /dev/null
+++ b/libavcodec/avs2.h
@@ -0,0 +1,41 @@
+/*
+ * AVS2 related definitions
+ *
+ * Copyright (C) 2022 Zhao Zhili, <zhilizhao@tencent.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
+ */
+
+#ifndef AVCODEC_AVS2_H
+#define AVCODEC_AVS2_H
+
+#define AVS2_SLICE_MAX_START_CODE    0x000001AF
+
+enum {
+    AVS2_SEQ_START_CODE         = 0xB0,
+    AVS2_SEQ_END_CODE           = 0xB1,
+    AVS2_USER_DATA_START_CODE   = 0xB2,
+    AVS2_INTRA_PIC_START_CODE   = 0xB3,
+    // reserved                 = 0xB4,
+    AVS2_EXTENSION_START_CODE   = 0xB5,
+    AVS2_INTER_PIC_START_CODE   = 0xB6,
+};
+
+#define AVS2_ISPIC(x)  ((x) == AVS2_INTRA_PIC_START_CODE || (x) == AVS2_INTER_PIC_START_CODE)
+#define AVS2_ISUNIT(x) ((x) == AVS2_SEQ_START_CODE || (x) == AVS2_SEQ_END_CODE || (x) == AVS2_USER_DATA_START_CODE || AVS2_ISPIC(x))
+
+#endif
diff --git a/libavcodec/avs2_parser.c b/libavcodec/avs2_parser.c
index b7d5d7774e..3755dbd78c 100644
--- a/libavcodec/avs2_parser.c
+++ b/libavcodec/avs2_parser.c
@@ -19,13 +19,9 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#include "avs2.h"
 #include "parser.h"
 
-#define AVS2_SLICE_MAX_START_CODE 0x000001AF
-
-#define AVS2_ISPIC(x)  ((x) == 0xB3 || (x) == 0xB6)
-#define AVS2_ISUNIT(x) ((x) == 0xB0 || (x) == 0xB1 || (x) == 0xB2 || AVS2_ISPIC(x))
-
 static int avs2_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size)
 {
     int pic_found  = pc->frame_start_found;