ffmpeg | branch: master | Ganesh Ajjanagadde <[email protected]> | Wed Dec 9 18:19:33 2015 -0500| [df679f12649d4184eebe02fe4cdd80c2952d0022] | committer: Ganesh Ajjanagadde
lavc/dcaenc: avoid wasteful cos calls cos has symmetry; use this. Reviewed-by: Paul B Mahol <[email protected]> Signed-off-by: Ganesh Ajjanagadde <[email protected]> > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=df679f12649d4184eebe02fe4cdd80c2952d0022 --- libavcodec/dcaenc.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/libavcodec/dcaenc.c b/libavcodec/dcaenc.c index 5a6bdac..6fcfb1a 100644 --- a/libavcodec/dcaenc.c +++ b/libavcodec/dcaenc.c @@ -169,8 +169,16 @@ static int encode_init(AVCodecContext *avctx) if (!cos_table[0]) { int j, k; - for (i = 0; i < 2048; i++) { + cos_table[0] = 0x7fffffff; + cos_table[512] = 0; + cos_table[1024] = -cos_table[0]; + for (i = 1; i < 512; i++) { cos_table[i] = (int32_t)(0x7fffffff * cos(M_PI * i / 1024)); + cos_table[1024-i] = -cos_table[i]; + cos_table[1024+i] = -cos_table[i]; + cos_table[2048-i] = cos_table[i]; + } + for (i = 0; i < 2048; i++) { cb_to_level[i] = (int32_t)(0x7fffffff * pow(10, -0.005 * i)); } _______________________________________________ ffmpeg-cvslog mailing list [email protected] http://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog
