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| author | Andreas Rheinhardt <andreas.rheinhardt@gmail.com> | 2020-11-06 10:14:22 +0100 |
|---|---|---|
| committer | Andreas Rheinhardt <andreas.rheinhardt@gmail.com> | 2020-12-08 17:51:46 +0100 |
| commit | 22241d12c7bc7f317832d8101ebed8d2db78a41f (patch) | |
| tree | 9e1dfe0ffa569a83987434cfe4485d14f545a6ca /libavcodec/vp3.c | |
| parent | 984fdfd042aeec7d48cd906661b2192568874730 (diff) | |
avcodec/vp3: Apply VLC offset during init
By switching to ff_init_vlc_from_lengths() one can apply both positive
as well as negative offsets for free; in this case it even saves space
because one replaces codes tables that don't fit into an uint8_t by
symbols tables that fit into an uint8_t or can even be completely
avoided as they are trivial.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Diffstat (limited to 'libavcodec/vp3.c')
| -rw-r--r-- | libavcodec/vp3.c | 31 |
1 files changed, 20 insertions, 11 deletions
diff --git a/libavcodec/vp3.c b/libavcodec/vp3.c index c4ad43a299..34c48f8725 100644 --- a/libavcodec/vp3.c +++ b/libavcodec/vp3.c @@ -48,6 +48,9 @@ #include "vp3dsp.h" #include "xiph.h" +#define VP4_MV_VLC_BITS 6 +#define SUPERBLOCK_VLC_BITS 6 + #define FRAGMENT_PIXELS 8 // FIXME split things out into their own arrays @@ -489,7 +492,7 @@ static int unpack_superblocks(Vp3DecodeContext *s, GetBitContext *gb) bit ^= 1; current_run = get_vlc2(gb, s->superblock_run_length_vlc.table, - 6, 2) + 1; + SUPERBLOCK_VLC_BITS, 2); if (current_run == 34) current_run += get_bits(gb, 12); @@ -523,7 +526,7 @@ static int unpack_superblocks(Vp3DecodeContext *s, GetBitContext *gb) bit ^= 1; current_run = get_vlc2(gb, s->superblock_run_length_vlc.table, - 6, 2) + 1; + SUPERBLOCK_VLC_BITS, 2); if (current_run == 34) current_run += get_bits(gb, 12); @@ -885,7 +888,8 @@ static int unpack_modes(Vp3DecodeContext *s, GetBitContext *gb) static int vp4_get_mv(Vp3DecodeContext *s, GetBitContext *gb, int axis, int last_motion) { - int v = get_vlc2(gb, s->vp4_mv_vlc[axis][vp4_mv_table_selector[FFABS(last_motion)]].table, 6, 2) - 31; + int v = get_vlc2(gb, s->vp4_mv_vlc[axis][vp4_mv_table_selector[FFABS(last_motion)]].table, + VP4_MV_VLC_BITS, 2); return last_motion < 0 ? -v : v; } @@ -1104,7 +1108,8 @@ static int unpack_block_qpis(Vp3DecodeContext *s, GetBitContext *gb) else bit ^= 1; - run_length = get_vlc2(gb, s->superblock_run_length_vlc.table, 6, 2) + 1; + run_length = get_vlc2(gb, s->superblock_run_length_vlc.table, + SUPERBLOCK_VLC_BITS, 2); if (run_length == 34) run_length += get_bits(gb, 12); blocks_decoded += run_length; @@ -2452,9 +2457,10 @@ static av_cold int vp3_decode_init(AVCodecContext *avctx) } } - if ((ret = init_vlc(&s->superblock_run_length_vlc, 6, 34, - &superblock_run_length_vlc_table[0][1], 4, 2, - &superblock_run_length_vlc_table[0][0], 4, 2, 0)) < 0) + ret = ff_init_vlc_from_lengths(&s->superblock_run_length_vlc, SUPERBLOCK_VLC_BITS, 34, + superblock_run_length_vlc_lens, 1, + NULL, 0, 0, 1, 0, avctx); + if (ret < 0) return ret; if ((ret = init_vlc(&s->fragment_run_length_vlc, 5, 30, @@ -2474,11 +2480,14 @@ static av_cold int vp3_decode_init(AVCodecContext *avctx) #if CONFIG_VP4_DECODER for (j = 0; j < 2; j++) - for (i = 0; i < 7; i++) - if ((ret = init_vlc(&s->vp4_mv_vlc[j][i], 6, 63, - &vp4_mv_vlc[j][i][0][1], 4, 2, - &vp4_mv_vlc[j][i][0][0], 4, 2, 0)) < 0) + for (i = 0; i < 7; i++) { + ret = ff_init_vlc_from_lengths(&s->vp4_mv_vlc[j][i], VP4_MV_VLC_BITS, 63, + &vp4_mv_vlc[j][i][0][1], 2, + &vp4_mv_vlc[j][i][0][0], 2, 1, -31, + 0, avctx); + if (ret < 0) return ret; + } /* version >= 2 */ for (i = 0; i < 2; i++) |