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| author | Michael Niedermayer <michaelni@gmx.at> | 2005-05-11 01:46:13 +0000 |
|---|---|---|
| committer | Michael Niedermayer <michaelni@gmx.at> | 2005-05-11 01:46:13 +0000 |
| commit | cea27ac7144ddc1451b84a30a6d8cf1ad271dfb5 (patch) | |
| tree | ae673770d4759ab017582d939eeeeea706e69e7a /libavcodec/bitstream.c | |
| parent | 0de1318a292be2be097fe0d449fa268b01bcc01d (diff) | |
| download | ffmpeg-cea27ac7144ddc1451b84a30a6d8cf1ad271dfb5.tar.gz | |
LE bitstream reader based upon a patch by (Balatoni Denes <dbalatoni programozo hu)
Originally committed as revision 4215 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec/bitstream.c')
| -rw-r--r-- | libavcodec/bitstream.c | 20 |
1 files changed, 13 insertions, 7 deletions
diff --git a/libavcodec/bitstream.c b/libavcodec/bitstream.c index 2678772c49..fcd4fd9cb2 100644 --- a/libavcodec/bitstream.c +++ b/libavcodec/bitstream.c @@ -132,14 +132,14 @@ static int build_table(VLC *vlc, int table_nb_bits, int nb_codes, const void *bits, int bits_wrap, int bits_size, const void *codes, int codes_wrap, int codes_size, - uint32_t code_prefix, int n_prefix, int use_static) + uint32_t code_prefix, int n_prefix, int flags) { - int i, j, k, n, table_size, table_index, nb, n1, index; + int i, j, k, n, table_size, table_index, nb, n1, index, code_prefix2; uint32_t code; VLC_TYPE (*table)[2]; table_size = 1 << table_nb_bits; - table_index = alloc_table(vlc, table_size, use_static); + table_index = alloc_table(vlc, table_size, flags & INIT_VLC_USE_STATIC); #ifdef DEBUG_VLC printf("new table index=%d size=%d code_prefix=%x n=%d\n", table_index, table_size, code_prefix, n_prefix); @@ -165,12 +165,18 @@ static int build_table(VLC *vlc, int table_nb_bits, #endif /* if code matches the prefix, it is in the table */ n -= n_prefix; - if (n > 0 && (code >> n) == code_prefix) { + if(flags & INIT_VLC_LE) + code_prefix2= code & (n_prefix>=32 ? 0xffffffff : (1 << n_prefix)-1); + else + code_prefix2= code >> n; + if (n > 0 && code_prefix2 == code_prefix) { if (n <= table_nb_bits) { /* no need to add another table */ j = (code << (table_nb_bits - n)) & (table_size - 1); nb = 1 << (table_nb_bits - n); for(k=0;k<nb;k++) { + if(flags & INIT_VLC_LE) + j = (code >> n_prefix) + (k<<n); #ifdef DEBUG_VLC av_log(NULL, AV_LOG_DEBUG, "%4x: code=%d n=%d\n", j, i, n); @@ -185,7 +191,7 @@ static int build_table(VLC *vlc, int table_nb_bits, } } else { n -= table_nb_bits; - j = (code >> n) & ((1 << table_nb_bits) - 1); + j = (code >> ((flags & INIT_VLC_LE) ? n_prefix : n)) & ((1 << table_nb_bits) - 1); #ifdef DEBUG_VLC printf("%4x: n=%d (subtable)\n", j, n); @@ -211,8 +217,8 @@ static int build_table(VLC *vlc, int table_nb_bits, index = build_table(vlc, n, nb_codes, bits, bits_wrap, bits_size, codes, codes_wrap, codes_size, - (code_prefix << table_nb_bits) | i, - n_prefix + table_nb_bits, use_static); + (flags & INIT_VLC_LE) ? (code_prefix | (i << n_prefix)) : ((code_prefix << table_nb_bits) | i), + n_prefix + table_nb_bits, flags); if (index < 0) return -1; /* note: realloc has been done, so reload tables */ |