diff options
| author | zhaoxiu.zeng <zhaoxiu.zeng@gmail.com> | 2015-02-25 00:28:45 +0800 |
|---|---|---|
| committer | Michael Niedermayer <michaelni@gmx.at> | 2015-02-28 14:31:40 +0100 |
| commit | 53cb0babb42df0da2877274fa04ce6aa02ff476a (patch) | |
| tree | abda38dc870a231c31160837cd7fefde40b3e493 /libavcodec/vc1_block.c | |
| parent | 5ee3a40f1cf86746d62cc75d505db9679703ba2a (diff) | |
| download | ffmpeg-streaming-53cb0babb42df0da2877274fa04ce6aa02ff476a.zip ffmpeg-streaming-53cb0babb42df0da2877274fa04ce6aa02ff476a.tar.gz | |
avcodec/vc1: simplify offset table and access
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Diffstat (limited to 'libavcodec/vc1_block.c')
| -rw-r--r-- | libavcodec/vc1_block.c | 50 |
1 files changed, 21 insertions, 29 deletions
diff --git a/libavcodec/vc1_block.c b/libavcodec/vc1_block.c index aa62ec2..d10a6a6 100644 --- a/libavcodec/vc1_block.c +++ b/libavcodec/vc1_block.c @@ -40,8 +40,10 @@ #define DC_VLC_BITS 9 // offset tables for interlaced picture MVDATA decoding -static const int offset_table1[9] = { 0, 1, 2, 4, 8, 16, 32, 64, 128 }; -static const int offset_table2[9] = { 0, 1, 3, 7, 15, 31, 63, 127, 255 }; +static const uint8_t offset_table[2][9] = { + { 0, 1, 2, 4, 8, 16, 32, 64, 128 }, + { 0, 1, 3, 7, 15, 31, 63, 127, 255 }, +}; /***********************************************************************/ /** @@ -216,22 +218,22 @@ static void vc1_put_signed_blocks_clamped(VC1Context *v) s->mb_intra = 1; \ } else { \ index1 = index % 6; \ - if (!s->quarter_sample && index1 == 5) val = 1; \ - else val = 0; \ - if (size_table[index1] - val > 0) \ - val = get_bits(gb, size_table[index1] - val); \ - else val = 0; \ - sign = 0 - (val&1); \ - _dmv_x = (sign ^ ((val>>1) + offset_table[index1])) - sign; \ + _dmv_x = offset_table[1][index1]; \ + val = size_table[index1] - (!s->quarter_sample && index1 == 5); \ + if (val > 0) { \ + val = get_bits(gb, val); \ + sign = 0 - (val & 1); \ + _dmv_x = (sign ^ ((val >> 1) + _dmv_x)) - sign; \ + } \ \ index1 = index / 6; \ - if (!s->quarter_sample && index1 == 5) val = 1; \ - else val = 0; \ - if (size_table[index1] - val > 0) \ - val = get_bits(gb, size_table[index1] - val); \ - else val = 0; \ - sign = 0 - (val & 1); \ - _dmv_y = (sign ^ ((val >> 1) + offset_table[index1])) - sign; \ + _dmv_y = offset_table[1][index1]; \ + val = size_table[index1] - (!s->quarter_sample && index1 == 5); \ + if (val > 0) { \ + val = get_bits(gb, val); \ + sign = 0 - (val & 1); \ + _dmv_y = (sign ^ ((val >> 1) + _dmv_y)) - sign; \ + } \ } static av_always_inline void get_mvdata_interlaced(VC1Context *v, int *dmv_x, @@ -242,7 +244,6 @@ static av_always_inline void get_mvdata_interlaced(VC1Context *v, int *dmv_x, GetBitContext *gb = &v->s.gb; int bits, esc; int val, sign; - const int* offs_tab; if (v->numref) { bits = VC1_2REF_MVDATA_VLC_BITS; @@ -277,26 +278,18 @@ static av_always_inline void get_mvdata_interlaced(VC1Context *v, int *dmv_x, } else { av_assert0(index < esc); - if (extend_x) - offs_tab = offset_table2; - else - offs_tab = offset_table1; index1 = (index + 1) % 9; if (index1 != 0) { val = get_bits(gb, index1 + extend_x); - sign = 0 -(val & 1); - *dmv_x = (sign ^ ((val >> 1) + offs_tab[index1])) - sign; + sign = 0 - (val & 1); + *dmv_x = (sign ^ ((val >> 1) + offset_table[extend_x][index1])) - sign; } else *dmv_x = 0; - if (extend_y) - offs_tab = offset_table2; - else - offs_tab = offset_table1; index1 = (index + 1) / 9; if (index1 > v->numref) { val = get_bits(gb, (index1 + (extend_y << v->numref)) >> v->numref); sign = 0 - (val & 1); - *dmv_y = (sign ^ ((val >> 1) + offs_tab[index1 >> v->numref])) - sign; + *dmv_y = (sign ^ ((val >> 1) + offset_table[extend_y][index1 >> v->numref])) - sign; } else *dmv_y = 0; if (v->numref && pred_flag) @@ -1321,7 +1314,6 @@ static int vc1_decode_p_block(VC1Context *v, int16_t block[64], int n, /** @} */ // Macroblock group static const int size_table [6] = { 0, 2, 3, 4, 5, 8 }; -static const int offset_table[6] = { 0, 1, 3, 7, 15, 31 }; /** Decode one P-frame MB */ |
