Move some definitions to header file.

Share them with upcoming demuxer module.
Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>

libavcodec/gif.h

+/*
+ * GIF format definitions
+ * Copyright (c) 2003 Fabrice Bellard
+ * Copyright (c) 2006 Baptiste Coudurier
+ * Copyright (c) 2012 Vitaliy E Sugrobov
+ *
+ * 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
+ */
+
+/**
+ * @file
+ * GIF format definitions.
+ */
+
+#ifndef AVCODEC_GIFDEFS_H
+#define AVCODEC_GIFDEFS_H
+
+#include <stdint.h>
+
+static const uint8_t gif87a_sig[6] = "GIF87a";
+static const uint8_t gif89a_sig[6] = "GIF89a";
+
+#define GCE_DISPOSAL_NONE       0
+#define GCE_DISPOSAL_INPLACE    1
+#define GCE_DISPOSAL_BACKGROUND 2
+#define GCE_DISPOSAL_RESTORE    3
+
+#define GIF_TRAILER                 0x3b
+#define GIF_EXTENSION_INTRODUCER    0x21
+#define GIF_IMAGE_SEPARATOR         0x2c
+#define GIF_GCE_EXT_LABEL           0xf9
+
+#endif /* AVCODEC_GIFDEFS_H */

libavcodec/gifdec.c

@@ -28,15 +28,8 @@
 #include "avcodec.h"
 #include "bytestream.h"
 #include "lzw.h"
+#include "gif.h"
 
-#define GCE_DISPOSAL_NONE       0
-#define GCE_DISPOSAL_INPLACE    1
-#define GCE_DISPOSAL_BACKGROUND 2
-#define GCE_DISPOSAL_RESTORE    3
-#define GIF_TRAILER                 0x3b
-#define GIF_EXTENSION_INTRODUCER    0x21
-#define GIF_IMAGE_SEPARATOR         0x2c
-#define GIF_GCE_EXT_LABEL           0xf9
 /* This value is intentionally set to "transparent white" color.
  * It is much better to have white background instead of black
  * when gif image converted to format which not support transparency.
@@ -83,8 +76,6 @@ typedef struct GifState {
     int trans_color;    /**< color value that is used instead of transparent color */
 } GifState;
 
-static const uint8_t gif87a_sig[6] = "GIF87a";
-static const uint8_t gif89a_sig[6] = "GIF89a";
 static void gif_read_palette(const uint8_t **buf, uint32_t *pal, int nb)
 {
     const uint8_t *pal_end = *buf + nb * 3;