new IDCT code by Michael Niedermayer (michaelni@gmx.at) - #define SIMPLE_IDCT to enable

Originally committed as revision 235 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 231 insertions, 0 deletions

diff --git a/libavcodec/simple_idct.c b/libavcodec/simple_idct.c
new file mode 100644
index 0000000000..5459b81b35
--- /dev/null
+++ b/libavcodec/simple_idct.c
@@ -0,0 +1,231 @@
+/*
+    Copyright (C) 2001 Michael Niedermayer (michaelni@gmx.at)
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program 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 General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+*/
+
+/*
+  based upon some outcommented c code from mpeg2dec (idct_mmx.c written by Aaron Holtzman <aholtzma@ess.engr.uvic.ca>)
+*/
+
+#include <inttypes.h>
+
+#include "simple_idct.h"
+
+#if 0
+#define W1 2841 /* 2048*sqrt (2)*cos (1*pi/16) */
+#define W2 2676 /* 2048*sqrt (2)*cos (2*pi/16) */
+#define W3 2408 /* 2048*sqrt (2)*cos (3*pi/16) */
+#define W4 2048 /* 2048*sqrt (2)*cos (4*pi/16) */
+#define W5 1609 /* 2048*sqrt (2)*cos (5*pi/16) */
+#define W6 1108 /* 2048*sqrt (2)*cos (6*pi/16) */
+#define W7 565  /* 2048*sqrt (2)*cos (7*pi/16) */
+#define ROW_SHIFT 8
+#define COL_SHIFT 17
+#else
+#define W1  22725  //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
+#define W2  21407  //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
+#define W3  19266  //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
+#define W4  16384  //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
+#define W5  12873  //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
+#define W6  8867   //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
+#define W7  4520   //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
+#define ROW_SHIFT 11
+#define COL_SHIFT 20 // 6
+#endif
+#if 1
+static void inline idctRow (int16_t * row)
+{
+	int a0, a1, a2, a3, b0, b1, b2, b3;
+	const int C1 =W1;
+	const int C2 =W2;
+	const int C3 =W3;
+	const int C4 =W4;
+	const int C5 =W5;
+	const int C6 =W6;
+	const int C7 =W7;
+
+	if( !(row[1] | row[2] |row[3] |row[4] |row[5] |row[6] | row[7])) {
+		row[0] = row[1] = row[2] = row[3] = row[4] =
+			row[5] = row[6] = row[7] = row[0]<<3;
+		return;
+	}
+
+	a0 = C4*row[0] + C2*row[2] + C4*row[4] + C6*row[6] + (1<<(ROW_SHIFT-1));
+	a1 = C4*row[0] + C6*row[2] - C4*row[4] - C2*row[6] + (1<<(ROW_SHIFT-1));
+	a2 = C4*row[0] - C6*row[2] - C4*row[4] + C2*row[6] + (1<<(ROW_SHIFT-1));
+	a3 = C4*row[0] - C2*row[2] + C4*row[4] - C6*row[6] + (1<<(ROW_SHIFT-1));
+
+	b0 = C1*row[1] + C3*row[3] + C5*row[5] + C7*row[7];
+	b1 = C3*row[1] - C7*row[3] - C1*row[5] - C5*row[7];
+	b2 = C5*row[1] - C1*row[3] + C7*row[5] + C3*row[7];
+	b3 = C7*row[1] - C5*row[3] + C3*row[5] - C1*row[7];
+
+	row[0] = (a0 + b0) >> ROW_SHIFT;
+	row[1] = (a1 + b1) >> ROW_SHIFT;
+	row[2] = (a2 + b2) >> ROW_SHIFT;
+	row[3] = (a3 + b3) >> ROW_SHIFT;
+	row[4] = (a3 - b3) >> ROW_SHIFT;
+	row[5] = (a2 - b2) >> ROW_SHIFT;
+	row[6] = (a1 - b1) >> ROW_SHIFT;
+	row[7] = (a0 - b0) >> ROW_SHIFT;
+}
+
+static void inline idctCol (int16_t * col)
+{
+	int a0, a1, a2, a3, b0, b1, b2, b3;
+	const int C1 =W1;
+	const int C2 =W2;
+	const int C3 =W3;
+	const int C4 =W4;
+	const int C5 =W5;
+	const int C6 =W6;
+	const int C7 =W7;
+/*
+	if( !(col[8*1] | col[8*2] |col[8*3] |col[8*4] |col[8*5] |col[8*6] | col[8*7])) {
+		col[8*0] = col[8*1] = col[8*2] = col[8*3] = col[8*4] =
+			col[8*5] = col[8*6] = col[8*7] = col[8*0]<<3;
+		return;
+	}*/
+	col[0] += (1<<(COL_SHIFT-1))/W4;
+	a0 = C4*col[8*0] + C2*col[8*2] + C4*col[8*4] + C6*col[8*6];
+	a1 = C4*col[8*0] + C6*col[8*2] - C4*col[8*4] - C2*col[8*6];
+	a2 = C4*col[8*0] - C6*col[8*2] - C4*col[8*4] + C2*col[8*6];
+	a3 = C4*col[8*0] - C2*col[8*2] + C4*col[8*4] - C6*col[8*6];
+
+	b0 = C1*col[8*1] + C3*col[8*3] + C5*col[8*5] + C7*col[8*7];
+	b1 = C3*col[8*1] - C7*col[8*3] - C1*col[8*5] - C5*col[8*7];
+	b2 = C5*col[8*1] - C1*col[8*3] + C7*col[8*5] + C3*col[8*7];
+	b3 = C7*col[8*1] - C5*col[8*3] + C3*col[8*5] - C1*col[8*7];
+
+	col[8*0] = (a0 + b0) >> COL_SHIFT;
+	col[8*1] = (a1 + b1) >> COL_SHIFT;
+	col[8*2] = (a2 + b2) >> COL_SHIFT;
+	col[8*3] = (a3 + b3) >> COL_SHIFT;
+	col[8*4] = (a3 - b3) >> COL_SHIFT;
+	col[8*5] = (a2 - b2) >> COL_SHIFT;
+	col[8*6] = (a1 - b1) >> COL_SHIFT;
+	col[8*7] = (a0 - b0) >> COL_SHIFT;
+}
+
+void simple_idct (short *block)
+{
+	int i;
+	for(i=0; i<8; i++)
+		idctRow(block + 8*i);
+
+	for(i=0; i<8; i++)
+		idctCol(block + i);
+
+}
+
+#else
+
+#define W1  22725  //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
+#define W2  21407  //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
+#define W3  19266  //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
+#define W4  16384  //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
+#define W5  12873  //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
+#define W6  8867   //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
+#define W7  4520   //cos(i*M_PI/16)*sqrt(2)*(1<<14) + 0.5
+#define COL_SHIFT 31 // 6
+
+static void inline idctRow (int32_t *out, int16_t * row)
+{
+	int a0, a1, a2, a3, b0, b1, b2, b3;
+	const int C1 =W1;
+	const int C2 =W2;
+	const int C3 =W3;
+	const int C4 =W4;
+	const int C5 =W5;
+	const int C6 =W6;
+	const int C7 =W7;
+/*
+	if( !(row[1] | row[2] |row[3] |row[4] |row[5] |row[6] | row[7])) {
+		row[0] = row[1] = row[2] = row[3] = row[4] =
+			row[5] = row[6] = row[7] = row[0]<<14;
+		return;
+	}
+*/
+	a0 = C4*row[0] + C2*row[2] + C4*row[4] + C6*row[6];
+	a1 = C4*row[0] + C6*row[2] - C4*row[4] - C2*row[6];
+	a2 = C4*row[0] - C6*row[2] - C4*row[4] + C2*row[6];
+	a3 = C4*row[0] - C2*row[2] + C4*row[4] - C6*row[6];
+
+	b0 = C1*row[1] + C3*row[3] + C5*row[5] + C7*row[7];
+	b1 = C3*row[1] - C7*row[3] - C1*row[5] - C5*row[7];
+	b2 = C5*row[1] - C1*row[3] + C7*row[5] + C3*row[7];
+	b3 = C7*row[1] - C5*row[3] + C3*row[5] - C1*row[7];
+
+	out[0] = (a0 + b0);
+	out[1] = (a1 + b1);
+	out[2] = (a2 + b2);
+	out[3] = (a3 + b3);
+	out[4] = (a3 - b3);
+	out[5] = (a2 - b2);
+	out[6] = (a1 - b1);
+	out[7] = (a0 - b0);
+}
+
+static void inline idctCol (int32_t *in, int16_t * col)
+{
+	int64_t a0, a1, a2, a3, b0, b1, b2, b3;
+	const int64_t C1 =W1;
+	const int64_t C2 =W2;
+	const int64_t C3 =W3;
+	const int64_t C4 =W4;
+	const int64_t C5 =W5;
+	const int64_t C6 =W6;
+	const int64_t C7 =W7;
+/*
+	if( !(col[8*1] | col[8*2] |col[8*3] |col[8*4] |col[8*5] |col[8*6] | col[8*7])) {
+		col[8*0] = col[8*1] = col[8*2] = col[8*3] = col[8*4] =
+			col[8*5] = col[8*6] = col[8*7] = col[8*0]<<3;
+		return;
+	}*/
+	in[0] += (1<<(COL_SHIFT-1))/W4;
+	a0 = C4*in[8*0] + C2*in[8*2] + C4*in[8*4] + C6*in[8*6];
+	a1 = C4*in[8*0] + C6*in[8*2] - C4*in[8*4] - C2*in[8*6];
+	a2 = C4*in[8*0] - C6*in[8*2] - C4*in[8*4] + C2*in[8*6];
+	a3 = C4*in[8*0] - C2*in[8*2] + C4*in[8*4] - C6*in[8*6];
+
+	b0 = C1*in[8*1] + C3*in[8*3] + C5*in[8*5] + C7*in[8*7];
+	b1 = C3*in[8*1] - C7*in[8*3] - C1*in[8*5] - C5*in[8*7];
+	b2 = C5*in[8*1] - C1*in[8*3] + C7*in[8*5] + C3*in[8*7];
+	b3 = C7*in[8*1] - C5*in[8*3] + C3*in[8*5] - C1*in[8*7];
+
+	col[8*0] = (a0 + b0) >> COL_SHIFT;
+	col[8*1] = (a1 + b1) >> COL_SHIFT;
+	col[8*2] = (a2 + b2) >> COL_SHIFT;
+	col[8*3] = (a3 + b3) >> COL_SHIFT;
+	col[8*4] = (a3 - b3) >> COL_SHIFT;
+	col[8*5] = (a2 - b2) >> COL_SHIFT;
+	col[8*6] = (a1 - b1) >> COL_SHIFT;
+	col[8*7] = (a0 - b0) >> COL_SHIFT;
+}
+
+void simple_idct (short *block)
+{
+	int i;
+	int32_t temp[64];
+	for(i=0; i<8; i++)
+		idctRow(temp+8*i, block + 8*i);
+
+	for(i=0; i<8; i++)
+		idctCol(temp+i, block + i);
+
+}
+
+#endif