diff --git a/libavcodec/eatqi.c b/libavcodec/eatqi.c
index 8f502b3c56..51eff20b65 100644
--- a/libavcodec/eatqi.c
+++ b/libavcodec/eatqi.c
@@ -36,8 +36,8 @@
 #include "eaidct.h"
 #include "idctdsp.h"
 #include "internal.h"
-#include "mpeg12.h"
 #include "mpeg12data.h"
+#include "mpeg12dec.h"
 
 typedef struct TqiContext {
     AVCodecContext *avctx;
diff --git a/libavcodec/mdec.c b/libavcodec/mdec.c
index 9f61256bc4..986712cd06 100644
--- a/libavcodec/mdec.c
+++ b/libavcodec/mdec.c
@@ -33,8 +33,9 @@
 #include "blockdsp.h"
 #include "bswapdsp.h"
 #include "idctdsp.h"
-#include "mpeg12.h"
+#include "internal.h"
 #include "mpeg12data.h"
+#include "mpeg12dec.h"
 #include "thread.h"
 
 typedef struct MDECContext {
diff --git a/libavcodec/mpeg12.c b/libavcodec/mpeg12.c
index 5520960b74..622cdfd299 100644
--- a/libavcodec/mpeg12.c
+++ b/libavcodec/mpeg12.c
@@ -35,6 +35,7 @@
 #include "mpegvideo.h"
 #include "mpeg12.h"
 #include "mpeg12data.h"
+#include "mpeg12dec.h"
 #include "mpegvideodata.h"
 #include "startcode.h"
 
@@ -234,7 +235,7 @@ int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size,
 
 int ff_mpeg1_decode_block_intra(GetBitContext *gb,
                                 const uint16_t *quant_matrix,
-                                uint8_t *const scantable, int last_dc[3],
+                                const uint8_t *scantable, int last_dc[3],
                                 int16_t *block, int index, int qscale)
 {
     int dc, diff, i = 0, component;
diff --git a/libavcodec/mpeg12.h b/libavcodec/mpeg12.h
index fb2b37e7c8..a405db6c2d 100644
--- a/libavcodec/mpeg12.h
+++ b/libavcodec/mpeg12.h
@@ -22,7 +22,6 @@
 #ifndef AVCODEC_MPEG12_H
 #define AVCODEC_MPEG12_H
 
-#include "mpeg12vlc.h"
 #include "mpegvideo.h"
 
 /* Start codes. */
@@ -37,38 +36,8 @@
 
 void ff_mpeg12_common_init(MpegEncContext *s);
 
-#define INIT_2D_VLC_RL(rl, static_size, flags)\
-{\
-    static RL_VLC_ELEM rl_vlc_table[static_size];\
-    rl.rl_vlc[0] = rl_vlc_table;\
-    ff_init_2d_vlc_rl(&rl, static_size, flags);\
-}
-
-void ff_init_2d_vlc_rl(RLTable *rl, unsigned static_size, int flags);
 void ff_mpeg1_init_uni_ac_vlc(const RLTable *rl, uint8_t *uni_ac_vlc_len);
 
-static inline int decode_dc(GetBitContext *gb, int component)
-{
-    int code, diff;
-
-    if (component == 0) {
-        code = get_vlc2(gb, ff_dc_lum_vlc.table, DC_VLC_BITS, 2);
-    } else {
-        code = get_vlc2(gb, ff_dc_chroma_vlc.table, DC_VLC_BITS, 2);
-    }
-    if (code == 0) {
-        diff = 0;
-    } else {
-        diff = get_xbits(gb, code);
-    }
-    return diff;
-}
-
-int ff_mpeg1_decode_block_intra(GetBitContext *gb,
-                                const uint16_t *quant_matrix,
-                                uint8_t *const scantable, int last_dc[3],
-                                int16_t *block, int index, int qscale);
-
 void ff_mpeg1_clean_buffers(MpegEncContext *s);
 #if FF_API_FLAG_TRUNCATED
 int ff_mpeg1_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size, AVCodecParserContext *s);
diff --git a/libavcodec/mpeg12dec.c b/libavcodec/mpeg12dec.c
index 860e86aa74..f15e402fd7 100644
--- a/libavcodec/mpeg12dec.c
+++ b/libavcodec/mpeg12dec.c
@@ -42,6 +42,7 @@
 #include "mpeg_er.h"
 #include "mpeg12.h"
 #include "mpeg12data.h"
+#include "mpeg12dec.h"
 #include "mpegutils.h"
 #include "mpegvideo.h"
 #include "mpegvideodata.h"
diff --git a/libavcodec/mpeg12dec.h b/libavcodec/mpeg12dec.h
new file mode 100644
index 0000000000..b4e94a92ce
--- /dev/null
+++ b/libavcodec/mpeg12dec.h
@@ -0,0 +1,60 @@
+/*
+ * MPEG-1/2 decoder header
+ * Copyright (c) 2007 Aurelien Jacobs <aurel@gnuage.org>
+ *
+ * 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_MPEG12DEC_H
+#define AVCODEC_MPEG12DEC_H
+
+#include "get_bits.h"
+#include "mpeg12vlc.h"
+#include "rl.h"
+
+#define INIT_2D_VLC_RL(rl, static_size, flags)\
+{\
+    static RL_VLC_ELEM rl_vlc_table[static_size];\
+    rl.rl_vlc[0] = rl_vlc_table;\
+    ff_init_2d_vlc_rl(&rl, static_size, flags);\
+}
+
+void ff_init_2d_vlc_rl(RLTable *rl, unsigned static_size, int flags);
+
+static inline int decode_dc(GetBitContext *gb, int component)
+{
+    int code, diff;
+
+    if (component == 0) {
+        code = get_vlc2(gb, ff_dc_lum_vlc.table, DC_VLC_BITS, 2);
+    } else {
+        code = get_vlc2(gb, ff_dc_chroma_vlc.table, DC_VLC_BITS, 2);
+    }
+    if (code == 0) {
+        diff = 0;
+    } else {
+        diff = get_xbits(gb, code);
+    }
+    return diff;
+}
+
+int ff_mpeg1_decode_block_intra(GetBitContext *gb,
+                                const uint16_t *quant_matrix,
+                                const uint8_t *scantable, int last_dc[3],
+                                int16_t *block, int index, int qscale);
+
+#endif /* AVCODEC_MPEG12DEC_H */
diff --git a/libavcodec/speedhq.c b/libavcodec/speedhq.c
index 743dacc6ce..fd4ea0d75e 100644
--- a/libavcodec/speedhq.c
+++ b/libavcodec/speedhq.c
@@ -31,11 +31,13 @@
 #include "libavutil/mem_internal.h"
 
 #include "avcodec.h"
+#include "blockdsp.h"
 #include "get_bits.h"
+#include "idctdsp.h"
 #include "internal.h"
 #include "libavutil/thread.h"
 #include "mathops.h"
-#include "mpeg12.h"
+#include "mpeg12dec.h"
 #include "mpeg12data.h"
 #include "mpeg12vlc.h"