Offseting by +1 is possible without adding dummy elements to the
beginning of the codes and lengths tables by switching to
ff_init_vlc_from_lengths() as this allows one to set the symbols
arbitrarily without incurring any penalty.
Signed-off-by: Andreas Rheinhardt <andreas.rheinha...@gmail.com>
---
I wonder whether the tables used to initialize VC1 VLCs should not be
put into a header of their own that is only included by vc1.c (the only
user of them) instead of vc1data.c. Given that I already touch all of
them, I could do it. What do other think of this?
libavcodec/vc1.c | 7 ++++---
libavcodec/vc1_block.c | 2 +-
libavcodec/vc1data.c | 27 +++++++++++++++++----------
libavcodec/vc1data.h | 5 ++---
4 files changed, 24 insertions(+), 17 deletions(-)
diff --git a/libavcodec/vc1.c b/libavcodec/vc1.c
index 9df778bcab..68180dc797 100644
--- a/libavcodec/vc1.c
+++ b/libavcodec/vc1.c
@@ -1616,9 +1616,10 @@ av_cold int ff_vc1_init_common(VC1Context *v)
ff_vc1_ttblk_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
ff_vc1_subblkpat_vlc[i].table = &vlc_table[vlc_offs[i *
3 + 2]];
ff_vc1_subblkpat_vlc[i].table_allocated = vlc_offs[i * 3 + 3] -
vlc_offs[i * 3 + 2];
- init_vlc(&ff_vc1_subblkpat_vlc[i], VC1_SUBBLKPAT_VLC_BITS, 15,
- ff_vc1_subblkpat_bits[i], 1, 1,
- ff_vc1_subblkpat_codes[i], 1, 1, INIT_VLC_USE_NEW_STATIC);
+ ff_init_vlc_from_lengths(&ff_vc1_subblkpat_vlc[i],
VC1_SUBBLKPAT_VLC_BITS, 15,
+ &ff_vc1_subblkpat_tabs[i][0][1], 2,
+ &ff_vc1_subblkpat_tabs[i][0][0], 2, 1,
+ 0, INIT_VLC_USE_NEW_STATIC);
}
for (i = 0; i < 4; i++) {
ff_vc1_4mv_block_pattern_vlc[i].table =
&vlc_table[vlc_offs[i * 3 + 9]];
diff --git a/libavcodec/vc1_block.c b/libavcodec/vc1_block.c
index 5c33170933..b8987b0015 100644
--- a/libavcodec/vc1_block.c
+++ b/libavcodec/vc1_block.c
@@ -1143,7 +1143,7 @@ static int vc1_decode_p_block(VC1Context *v, int16_t
block[64], int n,
ttblk = ff_vc1_ttblk_to_tt[v->tt_index][get_vlc2(gb,
ff_vc1_ttblk_vlc[v->tt_index].table, VC1_TTBLK_VLC_BITS, 1)];
}
if (ttblk == TT_4X4) {
- subblkpat = ~(get_vlc2(gb, ff_vc1_subblkpat_vlc[v->tt_index].table,
VC1_SUBBLKPAT_VLC_BITS, 1) + 1);
+ subblkpat = ~get_vlc2(gb, ff_vc1_subblkpat_vlc[v->tt_index].table,
VC1_SUBBLKPAT_VLC_BITS, 1);
}
if ((ttblk != TT_8X8 && ttblk != TT_4X4)
&& ((v->ttmbf || (ttmb != -1 && (ttmb & 8) && !first_block))
diff --git a/libavcodec/vc1data.c b/libavcodec/vc1data.c
index 19f1cad45f..e92d9b7310 100644
--- a/libavcodec/vc1data.c
+++ b/libavcodec/vc1data.c
@@ -921,16 +921,23 @@ const uint8_t ff_vc1_ttblk_bits[3][8] = {
{ 2, 3, 3, 3, 3, 3, 4, 4 }
};
-/* SUBBLKPAT tables, p93-94, reordered */
-const uint8_t ff_vc1_subblkpat_codes[3][15] = {
- { 14, 12, 7, 11, 9, 26, 2, 10, 27, 8, 0, 6, 1, 15, 1 },
- { 14, 0, 8, 15, 10, 4, 23, 13, 5, 9, 25, 3, 24, 22, 1 },
- { 5, 6, 2, 2, 8, 0, 28, 3, 1, 3, 29, 1, 19, 18, 15 }
-};
-const uint8_t ff_vc1_subblkpat_bits[3][15] = {
- { 5, 5, 5, 5, 5, 6, 4, 5, 6, 5, 4, 5, 4, 5, 1},
- { 4, 3, 4, 4, 4, 5, 5, 4, 5, 4, 5, 4, 5, 5, 2},
- { 3, 3, 4, 3, 4, 5, 5, 3, 5, 4, 5, 4, 5, 5, 4}
+/* SUBBLKPAT tables, p93-94, reordered and offset by 1 */
+const uint8_t ff_vc1_subblkpat_tabs[3][15][2] = {
+ {
+ { 0x0B, 4 }, { 0x0D, 4 }, { 0x07, 4 }, { 0x0C, 5 }, { 0x03, 5 },
+ { 0x0A, 5 }, { 0x05, 5 }, { 0x08, 5 }, { 0x04, 5 }, { 0x02, 5 },
+ { 0x06, 6 }, { 0x09, 6 }, { 0x01, 5 }, { 0x0E, 5 }, { 0x0F, 1 },
+ },
+ {
+ { 0x02, 3 }, { 0x06, 5 }, { 0x09, 5 }, { 0x0C, 4 }, { 0x0F, 2 },
+ { 0x03, 4 }, { 0x0A, 4 }, { 0x05, 4 }, { 0x0E, 5 }, { 0x07, 5 },
+ { 0x0D, 5 }, { 0x0B, 5 }, { 0x08, 4 }, { 0x01, 4 }, { 0x04, 4 },
+ },
+ {
+ { 0x06, 5 }, { 0x09, 5 }, { 0x0C, 4 }, { 0x03, 4 }, { 0x0A, 4 },
+ { 0x04, 3 }, { 0x08, 3 }, { 0x05, 4 }, { 0x0E, 5 }, { 0x0D, 5 },
+ { 0x01, 3 }, { 0x02, 3 }, { 0x07, 5 }, { 0x0B, 5 }, { 0x0F, 4 },
+ }
};
/* MV differential tables, p265 */
diff --git a/libavcodec/vc1data.h b/libavcodec/vc1data.h
index 90dd8baf61..6b141b0f76 100644
--- a/libavcodec/vc1data.h
+++ b/libavcodec/vc1data.h
@@ -152,9 +152,8 @@ extern const uint8_t ff_vc1_ttmb_bits[3][16];
extern const uint8_t ff_vc1_ttblk_codes[3][8];
extern const uint8_t ff_vc1_ttblk_bits[3][8];
-/* SUBBLKPAT tables, p93-94, reordered */
-extern const uint8_t ff_vc1_subblkpat_codes[3][15];
-extern const uint8_t ff_vc1_subblkpat_bits[3][15];
+/* SUBBLKPAT tables, p93-94, reordered and offset by 1 */
+extern const uint8_t ff_vc1_subblkpat_tabs[3][15][2];
/* MV differential tables, p265 */
extern const uint16_t ff_vc1_mv_diff_codes[4][73];
--
2.25.1
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
To unsubscribe, visit link above, or email
ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
