diff --git a/libavcodec/arm/idct.h b/libavcodec/arm/idct.h
new file mode 100644
index 0000000000..168d64b666
--- /dev/null
+++ b/libavcodec/arm/idct.h
@@ -0,0 +1,40 @@
+/*
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVCODEC_ARM_IDCT_H
+#define AVCODEC_ARM_IDCT_H
+
+#include <stdint.h>
+
+void ff_j_rev_dct_arm(int16_t *data);
+
+void ff_simple_idct_arm(int16_t *data);
+
+void ff_simple_idct_armv5te(int16_t *data);
+void ff_simple_idct_put_armv5te(uint8_t *dest, int line_size, int16_t *data);
+void ff_simple_idct_add_armv5te(uint8_t *dest, int line_size, int16_t *data);
+
+void ff_simple_idct_armv6(int16_t *data);
+void ff_simple_idct_put_armv6(uint8_t *dest, int line_size, int16_t *data);
+void ff_simple_idct_add_armv6(uint8_t *dest, int line_size, int16_t *data);
+
+void ff_simple_idct_neon(int16_t *data);
+void ff_simple_idct_put_neon(uint8_t *dest, int line_size, int16_t *data);
+void ff_simple_idct_add_neon(uint8_t *dest, int line_size, int16_t *data);
+
+#endif /* AVCODEC_ARM_IDCT_H */
diff --git a/libavcodec/arm/idctdsp_init_arm.c b/libavcodec/arm/idctdsp_init_arm.c
index cf75383922..0b32df0613 100644
--- a/libavcodec/arm/idctdsp_init_arm.c
+++ b/libavcodec/arm/idctdsp_init_arm.c
@@ -26,11 +26,9 @@
 #include "libavutil/arm/cpu.h"
 #include "libavcodec/avcodec.h"
 #include "libavcodec/idctdsp.h"
+#include "idct.h"
 #include "idctdsp_arm.h"
 
-void ff_j_rev_dct_arm(int16_t *data);
-void ff_simple_idct_arm(int16_t *data);
-
 /* XXX: local hack */
 static void (*ff_put_pixels_clamped)(const int16_t *block, uint8_t *pixels, int line_size);
 static void (*ff_add_pixels_clamped)(const int16_t *block, uint8_t *pixels, int line_size);
diff --git a/libavcodec/arm/idctdsp_init_armv5te.c b/libavcodec/arm/idctdsp_init_armv5te.c
index 1088563d76..251165dd74 100644
--- a/libavcodec/arm/idctdsp_init_armv5te.c
+++ b/libavcodec/arm/idctdsp_init_armv5te.c
@@ -23,12 +23,9 @@
 #include "libavutil/attributes.h"
 #include "libavcodec/avcodec.h"
 #include "libavcodec/idctdsp.h"
+#include "idct.h"
 #include "idctdsp_arm.h"
 
-void ff_simple_idct_armv5te(int16_t *data);
-void ff_simple_idct_put_armv5te(uint8_t *dest, int line_size, int16_t *data);
-void ff_simple_idct_add_armv5te(uint8_t *dest, int line_size, int16_t *data);
-
 av_cold void ff_idctdsp_init_armv5te(IDCTDSPContext *c, AVCodecContext *avctx,
                                      unsigned high_bit_depth)
 {
diff --git a/libavcodec/arm/idctdsp_init_armv6.c b/libavcodec/arm/idctdsp_init_armv6.c
index 1717421a97..8f0c49b142 100644
--- a/libavcodec/arm/idctdsp_init_armv6.c
+++ b/libavcodec/arm/idctdsp_init_armv6.c
@@ -23,12 +23,9 @@
 #include "libavutil/attributes.h"
 #include "libavcodec/avcodec.h"
 #include "libavcodec/idctdsp.h"
+#include "idct.h"
 #include "idctdsp_arm.h"
 
-void ff_simple_idct_armv6(int16_t *data);
-void ff_simple_idct_put_armv6(uint8_t *dest, int line_size, int16_t *data);
-void ff_simple_idct_add_armv6(uint8_t *dest, int line_size, int16_t *data);
-
 void ff_add_pixels_clamped_armv6(const int16_t *block, uint8_t *pixels,
                                  int line_size);
 
diff --git a/libavcodec/arm/idctdsp_init_neon.c b/libavcodec/arm/idctdsp_init_neon.c
index 66783d81d0..c94f7b6e5d 100644
--- a/libavcodec/arm/idctdsp_init_neon.c
+++ b/libavcodec/arm/idctdsp_init_neon.c
@@ -24,12 +24,9 @@
 #include "libavutil/attributes.h"
 #include "libavcodec/avcodec.h"
 #include "libavcodec/idctdsp.h"
+#include "idct.h"
 #include "idctdsp_arm.h"
 
-void ff_simple_idct_neon(int16_t *data);
-void ff_simple_idct_put_neon(uint8_t *dest, int line_size, int16_t *data);
-void ff_simple_idct_add_neon(uint8_t *dest, int line_size, int16_t *data);
-
 void ff_add_pixels_clamped_neon(const int16_t *, uint8_t *, int);
 void ff_put_pixels_clamped_neon(const int16_t *, uint8_t *, int);
 void ff_put_signed_pixels_clamped_neon(const int16_t *, uint8_t *, int);
diff --git a/libavcodec/dct-test.c b/libavcodec/dct-test.c
index baf5a8994a..d1393c4584 100644
--- a/libavcodec/dct-test.c
+++ b/libavcodec/dct-test.c
@@ -45,19 +45,13 @@
 #include "aandcttab.h"
 #include "faandct.h"
 #include "faanidct.h"
+#include "arm/idct.h"
 #include "ppc/fdct.h"
 #include "x86/fdct.h"
 #include "x86/idct_xvid.h"
 #include "x86/simple_idct.h"
 #include "dctref.h"
 
-// ARM
-void ff_j_rev_dct_arm(int16_t *data);
-void ff_simple_idct_arm(int16_t *data);
-void ff_simple_idct_armv5te(int16_t *data);
-void ff_simple_idct_armv6(int16_t *data);
-void ff_simple_idct_neon(int16_t *data);
-
 struct algo {
     const char *name;
     void (*func)(int16_t *block);