libavcodec/version: add a comment about FF_API_MPV_OPT deprecation

[ffmpeg] / libavcodec / dirac_vlc.c

diff --git a/libavcodec/dirac_vlc.c b/libavcodec/dirac_vlc.c
index 336d22a18298961d93e655839206a43dd6e4316e..496d8177cd88607c0af6c6197d8ce9bea0389660 100644 (file)
--- a/libavcodec/dirac_vlc.c
+++ b/libavcodec/dirac_vlc.c
@@ -37,7 +37,7 @@
 
 #define APPEND_RESIDUE(N, M)                                                   \
     N          |= M >> (N ## _bits);                                           \
-    N ## _bits +=      (M ## _bits)
+    N ## _bits  = (N ## _bits + (M ## _bits)) & 0x3F
 
 int ff_dirac_golomb_read_32bit(DiracGolombLUT *lut_ctx, const uint8_t *buf,
                                int bytes, uint8_t *_dst, int coeffs)
@@ -216,9 +216,14 @@ static void generate_offset_lut(DiracGolombLUT *lut, int off)
         INIT_RESIDUE(res);
         SET_RESIDUE(res, idx, LUT_BITS);
 
-        l->preamble      = CONVERT_TO_RESIDUE(res >> (RSIZE_BITS - off), off);
         l->preamble_bits = off;
-        l->sign = ((l->preamble >> (RSIZE_BITS - l->preamble_bits)) & 1) ? -1 : +1;
+        if (off) {
+            l->preamble  = CONVERT_TO_RESIDUE(res >> (RSIZE_BITS - off), off);
+            l->sign      = ((l->preamble >> (RSIZE_BITS - l->preamble_bits)) & 1) ? -1 : +1;
+        } else {
+            l->preamble  = 0;
+            l->sign = 1;
+        }
 
         search_for_golomb(l, res << off, LUT_BITS - off);
     }