[FFmpeg-cvslog] avcodec/mobiclip: Reduce size of VLCs, inline constants

[Andreas Rheinhardt]

ffmpeg | branch: master | Andreas Rheinhardt <andreas.rheinhardt at gmail.com> | Sat Oct 24 11:41:37 2020 +0200| [c4229ad0749faa26a86b998deda1754e04ce77bb] | committer: Andreas Rheinhardt

avcodec/mobiclip: Reduce size of VLCs, inline constants

The longest motion vector VLC for mobiclip is six bits long, so using
eight bits for the VLC table is wasteful. Furthermore, the length can be
inlined.

Reviewed-by: Michael Niedermayer <michael at niedermayer.cc>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at gmail.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=c4229ad0749faa26a86b998deda1754e04ce77bb
---

 libavcodec/mobiclip.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/libavcodec/mobiclip.c b/libavcodec/mobiclip.c
index 48467614ab..8d37243d87 100644
--- a/libavcodec/mobiclip.c
+++ b/libavcodec/mobiclip.c
@@ -31,6 +31,8 @@
 #include "golomb.h"
 #include "internal.h"
 
+#define MOBI_MV_VLC_BITS 6
+
 static const uint8_t zigzag4x4_tab[] =
 {
     0x00, 0x04, 0x01, 0x02, 0x05, 0x08, 0x0C, 0x09, 0x06, 0x03, 0x07, 0x0A,
@@ -364,14 +366,14 @@ static av_cold int mobiclip_init(AVCodecContext *avctx)
     }
 
     for (int j = 0; j < 16; j++) {
-        ret = ff_init_vlc_sparse(&s->mv_vlc[0][j], 8, mv_len[j],
+        ret = ff_init_vlc_sparse(&s->mv_vlc[0][j], MOBI_MV_VLC_BITS, mv_len[j],
                                  mv_bits_mods[j],  sizeof(*mv_bits_mods[j]),  sizeof(*mv_bits_mods[j]),
                                  mv_codes_mods[j], sizeof(*mv_codes_mods[j]), sizeof(*mv_codes_mods[j]),
                                  mv_syms_mods[j],  sizeof(*mv_syms_mods[j]),  sizeof(*mv_syms_mods[j]), 0);
         if (ret < 0)
             return ret;
 
-        ret = ff_init_vlc_sparse(&s->mv_vlc[1][j], 8, mv_len[j],
+        ret = ff_init_vlc_sparse(&s->mv_vlc[1][j], MOBI_MV_VLC_BITS, mv_len[j],
                                  mv_bits[j],  sizeof(*mv_bits[j]),  sizeof(*mv_bits[j]),
                                  mv_codes[j], sizeof(*mv_codes[j]), sizeof(*mv_codes[j]),
                                  mv_syms[j],  sizeof(*mv_syms[j]),  sizeof(*mv_syms[j]), 0);
@@ -1259,7 +1261,7 @@ static int predict_motion(AVCodecContext *avctx,
             int ret, idx2;
 
             idx2 = get_vlc2(gb, s->mv_vlc[s->moflex][tidx].table,
-                            s->mv_vlc[s->moflex][tidx].bits, 1);
+                            MOBI_MV_VLC_BITS, 1);
             if (idx2 < 0)
                 return AVERROR_INVALIDDATA;
 
@@ -1335,7 +1337,7 @@ static int mobiclip_decode(AVCodecContext *avctx, void *data,
                 motion[x / 16 + 2].y = 0;
 
                 idx = get_vlc2(gb, s->mv_vlc[s->moflex][0].table,
-                                   s->mv_vlc[s->moflex][0].bits, 1);
+                                   MOBI_MV_VLC_BITS, 1);
                 if (idx < 0)
                     return AVERROR_INVALIDDATA;