hpeldsp: Add half-pel functions (currently copies of dsputil)

Signed-off-by: Martin Storsjö <martin@martin.st>

1 files changed, 97 insertions, 0 deletions

diff --git a/libavcodec/hpeldsp.h b/libavcodec/hpeldsp.h
new file mode 100644
index 0000000000..84d567307f
--- /dev/null
+++ b/libavcodec/hpeldsp.h
@@ -0,0 +1,97 @@
+/*
+ * Half-pel DSP functions.
+ * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
+ * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * 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
+ */
+
+/**
+ * @file
+ * Half-pel DSP functions.
+ */
+
+#ifndef AVCODEC_HPELDSP_H
+#define AVCODEC_HPELDSP_H
+
+#include <stdint.h>
+#include <stddef.h>
+
+/* add and put pixel (decoding) */
+// blocksizes for hpel_pixels_func are 8x4,8x8 16x8 16x16
+// h for hpel_pixels_func is limited to {width/2, width} but never larger
+// than 16 and never smaller than 4
+typedef void (*hpel_pixels_func)(uint8_t *block /*align width (8 or 16)*/,
+                                 const uint8_t *pixels /*align 1*/,
+                                 ptrdiff_t line_size, int h);
+
+/**
+ * Half-pel DSP context.
+ */
+typedef struct HpelDSPContext {
+    /**
+     * Halfpel motion compensation with rounding (a+b+1)>>1.
+     * this is an array[4][4] of motion compensation functions for 4
+     * horizontal blocksizes (8,16) and the 4 halfpel positions<br>
+     * *pixels_tab[ 0->16xH 1->8xH ][ xhalfpel + 2*yhalfpel ]
+     * @param block destination where the result is stored
+     * @param pixels source
+     * @param line_size number of bytes in a horizontal line of block
+     * @param h height
+     */
+    hpel_pixels_func put_pixels_tab[4][4];
+
+    /**
+     * Halfpel motion compensation with rounding (a+b+1)>>1.
+     * This is an array[4][4] of motion compensation functions for 4
+     * horizontal blocksizes (8,16) and the 4 halfpel positions<br>
+     * *pixels_tab[ 0->16xH 1->8xH ][ xhalfpel + 2*yhalfpel ]
+     * @param block destination into which the result is averaged (a+b+1)>>1
+     * @param pixels source
+     * @param line_size number of bytes in a horizontal line of block
+     * @param h height
+     */
+    hpel_pixels_func avg_pixels_tab[4][4];
+
+    /**
+     * Halfpel motion compensation with no rounding (a+b)>>1.
+     * this is an array[2][4] of motion compensation functions for 2
+     * horizontal blocksizes (8,16) and the 4 halfpel positions<br>
+     * *pixels_tab[ 0->16xH 1->8xH ][ xhalfpel + 2*yhalfpel ]
+     * @param block destination where the result is stored
+     * @param pixels source
+     * @param line_size number of bytes in a horizontal line of block
+     * @param h height
+     */
+    hpel_pixels_func put_no_rnd_pixels_tab[2][4];
+
+    /**
+     * Halfpel motion compensation with no rounding (a+b)>>1.
+     * this is an array[4] of motion compensation functions for 1
+     * horizontal blocksize (16) and the 4 halfpel positions<br>
+     * *pixels_tab[0][ xhalfpel + 2*yhalfpel ]
+     * @param block destination into which the result is averaged (a+b)>>1
+     * @param pixels source
+     * @param line_size number of bytes in a horizontal line of block
+     * @param h height
+     */
+    hpel_pixels_func avg_no_rnd_pixels_tab[4];
+} HpelDSPContext;
+
+void ff_hpeldsp_init(HpelDSPContext *c, int flags);
+
+#endif /* AVCODEC_HPELDSP_H */