vf_psnr: sse2 optimizations for sum-squared-error.

The internal line accumulator for 16bit can overflow, so I changed that
from int to uint64_t in the C code. The matching assembly looks a little
weird but output looks correct.

(avx2 should be trivial to add later.)

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Reviewed-by: James Almer <jamrial@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

1 files changed, 33 insertions, 0 deletions

diff --git a/libavfilter/psnr.h b/libavfilter/psnr.h
new file mode 100644
index 0000000000..efe94da23c
--- /dev/null
+++ b/libavfilter/psnr.h
@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2015 Ronald S. Bultje <rsbultje@gmail.com>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ *
+ * 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser 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
+ */
+
+#ifndef LIBAVFILTER_PSNR_H
+#define LIBAVFILTER_PSNR_H
+
+#include <stddef.h>
+#include <stdint.h>
+
+typedef struct PSNRDSPContext {
+    uint64_t (*sse_line)(const uint8_t *buf, const uint8_t *ref, int w);
+} PSNRDSPContext;
+
+void ff_psnr_init_x86(PSNRDSPContext *dsp, int bpp);
+
+#endif /* LIBAVFILTER_PSNR_H */