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authorMike Melanson <mike@multimedia.cx>2005-05-21 01:12:41 +0000
committerMike Melanson <mike@multimedia.cx>2005-05-21 01:12:41 +0000
commit7f9926a45eeab7e25b9e381fc35b1342fde826cb (patch)
treef83017488932d78d9b530aabcd3c054df8906aa8 /libavcodec
parent3f2bf07ba72bf4caf24cc567916f146b7baaa7c0 (diff)
another bitstream extraction to optimize: fixed-length motion vectors
Originally committed as revision 4286 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec')
-rw-r--r--libavcodec/vp3.c11
-rw-r--r--libavcodec/vp3data.h11
2 files changed, 22 insertions, 0 deletions
diff --git a/libavcodec/vp3.c b/libavcodec/vp3.c
index 1f0718e3d7..160dcfb5a8 100644
--- a/libavcodec/vp3.c
+++ b/libavcodec/vp3.c
@@ -1540,9 +1540,15 @@ static int unpack_vectors(Vp3DecodeContext *s, GetBitContext *gb)
motion_y[0] = get_motion_vector_vlc(gb);
#endif
} else {
+#if 1
+ motion_x[0] = fixed_motion_vector_table[get_bits(gb, 6)];
+ motion_y[0] = fixed_motion_vector_table[get_bits(gb, 6)];
+#else
motion_x[0] = get_motion_vector_fixed(gb);
motion_y[0] = get_motion_vector_fixed(gb);
+#endif
}
+
for (k = 1; k < 6; k++) {
motion_x[k] = motion_x[0];
motion_y[k] = motion_y[0];
@@ -1572,8 +1578,13 @@ static int unpack_vectors(Vp3DecodeContext *s, GetBitContext *gb)
motion_y[k] = get_motion_vector_vlc(gb);
#endif
} else {
+#if 1
+ motion_x[k] = fixed_motion_vector_table[get_bits(gb, 6)];
+ motion_y[k] = fixed_motion_vector_table[get_bits(gb, 6)];
+#else
motion_x[k] = get_motion_vector_fixed(gb);
motion_y[k] = get_motion_vector_fixed(gb);
+#endif
}
motion_x[4] += motion_x[k];
motion_y[4] += motion_y[k];
diff --git a/libavcodec/vp3data.h b/libavcodec/vp3data.h
index 9fa1ffa62b..8bead2fc15 100644
--- a/libavcodec/vp3data.h
+++ b/libavcodec/vp3data.h
@@ -163,6 +163,17 @@ static const int motion_vector_table[63] = {
24, -24, 25, -25, 26, -26, 27, -27, 28, -28, 29, -29, 30, -30, 31, -31
};
+static const int8_t fixed_motion_vector_table[64] = {
+ 0, 0, 1, -1, 2, -2, 3, -3,
+ 4, -4, 5, -5, 6, -6, 7, -7,
+ 8, -8, 9, -9, 10, -10, 11, -11,
+ 12, -12, 13, -13, 14, -14, 15, -15,
+ 16, -16, 17, -17, 18, -18, 19, -19,
+ 20, -20, 21, -21, 22, -22, 23, -23,
+ 24, -24, 25, -25, 26, -26, 27, -27,
+ 28, -28, 29, -29, 30, -30, 31, -31
+};
+
/* only tokens 0..6 indicate eob runs */
static const int eob_run_base[7] = {
1, 2, 3, 4, 8, 16, 0