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authorDiego Biurrun <diego@biurrun.de>2005-06-11 18:18:13 +0000
committerDiego Biurrun <diego@biurrun.de>2005-06-11 18:18:13 +0000
commitc5a44f571586b524c8a4f71aa896d25a682318e7 (patch)
tree0d8986e115bbd704203da4b4b1fdd9fe1d3cc1e1 /doc/optimization.txt
parent79cc8267f4f91e8f86b2e5120c137fef9d1baf3b (diff)
spelling/phrasing fixes, mostly by Mans
Originally committed as revision 4378 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'doc/optimization.txt')
-rw-r--r--doc/optimization.txt17
1 files changed, 9 insertions, 8 deletions
diff --git a/doc/optimization.txt b/doc/optimization.txt
index d5ae06d76d..ac24976930 100644
--- a/doc/optimization.txt
+++ b/doc/optimization.txt
@@ -1,7 +1,7 @@
optimization Tips (for libavcodec):
What to optimize:
-If you plan to do non-x86 architecture specific optimiztions (SIMD normally)
+If you plan to do non-x86 architecture specific optimizations (SIMD normally),
then take a look in the i386/ directory, as most important functions are
already optimized for MMX.
@@ -14,10 +14,11 @@ As many functions, like the C ones tend to be a bit unreadable currently
because of optimizations it is difficult to understand them (and write
architecture specific versions, or optimize the C functions further) it is
recommended to look at older CVS versions of the interesting files (just use
-ViewCVS at http://www1.mplayerhq.hu/cgi-bin/cvsweb.cgi/ffmpeg/?cvsroot=FFMpeg)
-or perhaps look into the other architecture-specific versions in i386/, ppc/,
-alpha/, ... Even if you don't understand the instructions exactly it could
-help understanding the functions & how they can be optimized.
+ViewCVS at http://www1.mplayerhq.hu/cgi-bin/cvsweb.cgi/ffmpeg/?cvsroot=FFMpeg).
+Alternatively, look into the other architecture-specific versions in the i386/,
+ppc/, alpha/ subdirectories. Even if you don't exactly understand the
+instructions, it could help understanding the functions and how they
+can be optimized.
NOTE: If you still don't understand some function, ask at our mailing list!!!
(http://www1.mplayerhq.hu/mailman/listinfo/ffmpeg-devel)
@@ -33,7 +34,7 @@ put(_no_rnd)_pixels{,_x2,_y2,_xy2}
avg_pixels{,_x2,_y2,_xy2}
Used in motion compensation of B-frames.
- These are less important then the put*pixels functions.
+ These are less important than the put*pixels functions.
avg_no_rnd_pixels*
unused
@@ -43,7 +44,7 @@ pix_abs16x16{,_x2,_y2,_xy2}
pix_abs8x8{,_x2,_y2,_xy2}
Used in motion estimation (encoding) with SAD of MPEG-4 4MV only.
- These are less important then the pix_abs16x16* functions.
+ These are less important than the pix_abs16x16* functions.
put_mspel8_mc* / wmv2_mspel8*
Used only in WMV2.
@@ -128,7 +129,7 @@ BTW, most of these functions are in dsputil.c/.h, some are in mpegvideo.c/.h.
Alignment:
Some instructions on some architectures have strict alignment restrictions,
-for example most SSE/SSE2 inctructios on x86.
+for example most SSE/SSE2 instructions on x86.
The minimum guaranteed alignment is written in the .h files, for example:
void (*put_pixels_clamped)(const DCTELEM *block/*align 16*/, UINT8 *pixels/*align 8*/, int line_size);