Add gradfun filter, ported from MPlayer.

Patch by Nolan L nol888 <=> gmail >=< com.

See thread:
Subject: [FFmpeg-devel] [PATCH] Port gradfun to libavfilter (GCI)
Date: Mon, 29 Nov 2010 07:18:14 -0500

Originally committed as revision 25942 to svn://svn.ffmpeg.org/ffmpeg/trunk

2 files changed, 163 insertions, 0 deletions

diff --git a/libavfilter/x86/Makefile b/libavfilter/x86/Makefile
index 716048c..e98693d 100644
--- a/libavfilter/x86/Makefile
+++ b/libavfilter/x86/Makefile
@@ -1 +1,2 @@
 MMX-OBJS-$(CONFIG_YADIF_FILTER)              += x86/yadif.o
+MMX-OBJS-$(CONFIG_GRADFUN_FILTER)            += x86/gradfun.o
diff --git a/libavfilter/x86/gradfun.c b/libavfilter/x86/gradfun.c
new file mode 100644
index 0000000..894a44b
--- /dev/null
+++ b/libavfilter/x86/gradfun.c
@@ -0,0 +1,162 @@
+/*
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ *
+ * 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU 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.
+ */
+
+#include "libavutil/cpu.h"
+#include "libavutil/x86_cpu.h"
+#include "libavfilter/gradfun.h"
+
+DECLARE_ALIGNED(16, static const uint16_t, pw_7f)[8] = {0x7F,0x7F,0x7F,0x7F,0x7F,0x7F,0x7F,0x7F};
+DECLARE_ALIGNED(16, static const uint16_t, pw_ff)[8] = {0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF};
+
+void ff_gradfun_filter_line_mmx2(uint8_t *dst, uint8_t *src, uint16_t *dc, int width, int thresh, const uint16_t *dithers)
+{
+#if HAVE_MMX
+    intptr_t x;
+    if (width & 3) {
+        x = width & ~3;
+        ff_gradfun_filter_line_c(dst + x, src + x, dc + x / 2, width - x, thresh, dithers);
+        width = x;
+    }
+    x = -width;
+    __asm__ volatile(
+        "movd          %4, %%mm5 \n"
+        "pxor       %%mm7, %%mm7 \n"
+        "pshufw $0, %%mm5, %%mm5 \n"
+        "movq          %6, %%mm6 \n"
+        "movq          %5, %%mm4 \n"
+        "1: \n"
+        "movd     (%2,%0), %%mm0 \n"
+        "movd     (%3,%0), %%mm1 \n"
+        "punpcklbw  %%mm7, %%mm0 \n"
+        "punpcklwd  %%mm1, %%mm1 \n"
+        "psllw         $7, %%mm0 \n"
+        "pxor       %%mm2, %%mm2 \n"
+        "psubw      %%mm0, %%mm1 \n" // delta = dc - pix
+        "psubw      %%mm1, %%mm2 \n"
+        "pmaxsw     %%mm1, %%mm2 \n"
+        "pmulhuw    %%mm5, %%mm2 \n" // m = abs(delta) * thresh >> 16
+        "psubw      %%mm6, %%mm2 \n"
+        "pminsw     %%mm7, %%mm2 \n" // m = -max(0, 127-m)
+        "pmullw     %%mm2, %%mm2 \n"
+        "paddw      %%mm4, %%mm0 \n" // pix += dither
+        "pmulhw     %%mm2, %%mm1 \n"
+        "psllw         $2, %%mm1 \n" // m = m*m*delta >> 14
+        "paddw      %%mm1, %%mm0 \n" // pix += m
+        "psraw         $7, %%mm0 \n"
+        "packuswb   %%mm0, %%mm0 \n"
+        "movd       %%mm0, (%1,%0) \n" // dst = clip(pix>>7)
+        "add           $4, %0 \n"
+        "jl 1b \n"
+        "emms \n"
+        :"+r"(x)
+        :"r"(dst+width), "r"(src+width), "r"(dc+width/2),
+         "rm"(thresh), "m"(*dithers), "m"(*pw_7f)
+        :"memory"
+    );
+#endif
+}
+
+void ff_gradfun_filter_line_ssse3(uint8_t *dst, uint8_t *src, uint16_t *dc, int width, int thresh, const uint16_t *dithers)
+{
+#if HAVE_SSSE3
+    intptr_t x;
+    if (width & 7) {
+        // could be 10% faster if I somehow eliminated this
+        x = width & ~7;
+        ff_gradfun_filter_line_c(dst + x, src + x, dc + x / 2, width - x, thresh, dithers);
+        width = x;
+    }
+    x = -width;
+    __asm__ volatile(
+        "movd           %4, %%xmm5 \n"
+        "pxor       %%xmm7, %%xmm7 \n"
+        "pshuflw $0,%%xmm5, %%xmm5 \n"
+        "movdqa         %6, %%xmm6 \n"
+        "punpcklqdq %%xmm5, %%xmm5 \n"
+        "movdqa         %5, %%xmm4 \n"
+        "1: \n"
+        "movq      (%2,%0), %%xmm0 \n"
+        "movq      (%3,%0), %%xmm1 \n"
+        "punpcklbw  %%xmm7, %%xmm0 \n"
+        "punpcklwd  %%xmm1, %%xmm1 \n"
+        "psllw          $7, %%xmm0 \n"
+        "psubw      %%xmm0, %%xmm1 \n" // delta = dc - pix
+        "pabsw      %%xmm1, %%xmm2 \n"
+        "pmulhuw    %%xmm5, %%xmm2 \n" // m = abs(delta) * thresh >> 16
+        "psubw      %%xmm6, %%xmm2 \n"
+        "pminsw     %%xmm7, %%xmm2 \n" // m = -max(0, 127-m)
+        "pmullw     %%xmm2, %%xmm2 \n"
+        "psllw          $1, %%xmm2 \n"
+        "paddw      %%xmm4, %%xmm0 \n" // pix += dither
+        "pmulhrsw   %%xmm2, %%xmm1 \n" // m = m*m*delta >> 14
+        "paddw      %%xmm1, %%xmm0 \n" // pix += m
+        "psraw          $7, %%xmm0 \n"
+        "packuswb   %%xmm0, %%xmm0 \n"
+        "movq       %%xmm0, (%1,%0) \n" // dst = clip(pix>>7)
+        "add            $8, %0 \n"
+        "jl 1b \n"
+        :"+&r"(x)
+        :"r"(dst+width), "r"(src+width), "r"(dc+width/2),
+         "rm"(thresh), "m"(*dithers), "m"(*pw_7f)
+        :"memory"
+    );
+#endif // HAVE_SSSE3
+}
+
+void ff_gradfun_blur_line_sse2(uint16_t *dc, uint16_t *buf, uint16_t *buf1, uint8_t *src, int src_linesize, int width)
+{
+#if HAVE_SSE
+#define BLURV(load)\
+    intptr_t x = -2*width;\
+    __asm__ volatile(\
+        "movdqa %6, %%xmm7 \n"\
+        "1: \n"\
+        load"   (%4,%0), %%xmm0 \n"\
+        load"   (%5,%0), %%xmm1 \n"\
+        "movdqa  %%xmm0, %%xmm2 \n"\
+        "movdqa  %%xmm1, %%xmm3 \n"\
+        "psrlw       $8, %%xmm0 \n"\
+        "psrlw       $8, %%xmm1 \n"\
+        "pand    %%xmm7, %%xmm2 \n"\
+        "pand    %%xmm7, %%xmm3 \n"\
+        "paddw   %%xmm1, %%xmm0 \n"\
+        "paddw   %%xmm3, %%xmm2 \n"\
+        "paddw   %%xmm2, %%xmm0 \n"\
+        "paddw  (%2,%0), %%xmm0 \n"\
+        "movdqa (%1,%0), %%xmm1 \n"\
+        "movdqa  %%xmm0, (%1,%0) \n"\
+        "psubw   %%xmm1, %%xmm0 \n"\
+        "movdqa  %%xmm0, (%3,%0) \n"\
+        "add        $16, %0 \n"\
+        "jl 1b \n"\
+        :"+&r"(x)\
+        :"r"(buf+width),\
+         "r"(buf1+width),\
+         "r"(dc+width),\
+         "r"(src+width*2),\
+         "r"(src+width*2+src_linesize),\
+         "m"(*pw_ff)\
+        :"memory"\
+    );
+    if (((intptr_t) src | src_linesize) & 15) {
+        BLURV("movdqu");
+    } else {
+        BLURV("movdqa");
+    }
+#endif // HAVE_SSE
+}