Alpha optimizations by Falk Hueffner <falk.hueffner@student.uni-tuebingen.de>

Originally committed as revision 274 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 88 insertions, 0 deletions

diff --git a/libavcodec/alpha/mpegvideo_alpha.c b/libavcodec/alpha/mpegvideo_alpha.c
new file mode 100644
index 0000000000..db4fd3a9db
--- /dev/null
+++ b/libavcodec/alpha/mpegvideo_alpha.c
@@ -0,0 +1,88 @@
+/*
+ * Alpha optimized DSP utils
+ * Copyright (c) 2002 Falk Hueffner <falk@debian.org>
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "asm.h"
+#include "../dsputil.h"
+#include "../mpegvideo.h"
+
+extern UINT8 zigzag_end[64];
+
+static void dct_unquantize_h263_axp(MpegEncContext *s, 
+				    DCTELEM *block, int n, int qscale)
+{
+    int i, level;
+    UINT64 qmul, qadd;
+    if (s->mb_intra) {
+        if (n < 4) 
+            block[0] = block[0] * s->y_dc_scale;
+        else
+            block[0] = block[0] * s->c_dc_scale;
+	/* Catch up to aligned point.  */
+	qmul = s->qscale << 1;
+	qadd = (s->qscale - 1) | 1;
+	for (i = 1; i < 4; ++i) {
+	    level = block[i];
+	    if (level) {
+		if (level < 0) {
+		    level = level * qmul - qadd;
+		} else {
+		    level = level * qmul + qadd;
+		}
+		block[i] = level;
+	    }
+	}
+	block += 4;
+	i = 60 / 4;
+    } else {
+        i = zigzag_end[s->block_last_index[n]] / 4;
+    }
+    qmul = s->qscale << 1;
+    qadd = WORD_VEC((qscale - 1) | 1);
+    do {
+	UINT64 levels, negmask, zeromask, corr;
+	levels = ldq(block);
+	if (levels == 0)
+	    continue;
+	zeromask = cmpbge(0, levels);
+	zeromask &= zeromask >> 1;
+	/* Negate all negative words.  */
+	negmask = maxsw4(levels, WORD_VEC(0xffff)); /* negative -> ffff (-1) */
+	negmask = minsw4(negmask, 0);		    /* positive -> 0000 (0) */
+	corr    = negmask & WORD_VEC(0x0001); /* twos-complement correction */
+	levels ^= negmask;
+	levels += corr;
+
+	levels = levels * qmul;
+	levels += zap(qadd, zeromask);
+
+	/* Re-negate negative words.  */
+	levels -= corr;
+	levels ^= negmask;
+
+	stq(levels, block);
+    } while (block += 4, --i);
+}
+
+void MPV_common_init_axp(MpegEncContext *s)
+{
+    if (amask(AMASK_MVI) == 0) {
+        if (s->out_format == FMT_H263)
+	    s->dct_unquantize = dct_unquantize_h263_axp;
+    }
+}