ffmpeg | branch: master | Andreas Rheinhardt <andreas.rheinhardt@gmail.com> | Tue Dec 29 22:09:10 2020 +0100| [9f38fac053010205806ece11e6aea9b7d3bde041] | committer: Andreas Rheinhardt avcodec/h261dec: Make VLC smaller The VLC for the macroblock address increment uses nine bits; yet there is no code with this length: All codes are either shorter or longer. So one can make the table smaller without changing the amount of codes that need more than one round of parsing. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=9f38fac05301020580...
libavcodec/h261dec.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/libavcodec/h261dec.c b/libavcodec/h261dec.c index 817453f60c..2b3408d7b3 100644 --- a/libavcodec/h261dec.c +++ b/libavcodec/h261dec.c @@ -35,7 +35,7 @@ #include "h261.h" #include "internal.h" -#define H261_MBA_VLC_BITS 9 +#define H261_MBA_VLC_BITS 8 #define H261_MTYPE_VLC_BITS 6 #define H261_MV_VLC_BITS 7 #define H261_CBP_VLC_BITS 9 @@ -52,7 +52,7 @@ static av_cold void h261_decode_init_static(void) { INIT_VLC_STATIC(&h261_mba_vlc, H261_MBA_VLC_BITS, 35, ff_h261_mba_bits, 1, 1, - ff_h261_mba_code, 1, 1, 662); + ff_h261_mba_code, 1, 1, 540); INIT_VLC_STATIC(&h261_mtype_vlc, H261_MTYPE_VLC_BITS, 10, ff_h261_mtype_bits, 1, 1, ff_h261_mtype_code, 1, 1, 80);