X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fbitstream.c;h=f77b9c4e3f624a088745daceab790af6271a24d2;hb=cd2ffb67ad9e9fec1766c501ad33e85dc934eeed;hp=067a58b836e87f4ee08f465e675a7549c5da2418;hpb=3224079956811c29f6698235122b593e2d520343;p=ffmpeg diff --git a/libavcodec/bitstream.c b/libavcodec/bitstream.c index 067a58b836e..f77b9c4e3f6 100644 --- a/libavcodec/bitstream.c +++ b/libavcodec/bitstream.c @@ -6,25 +6,25 @@ * * alternative bitstream reader & writer by Michael Niedermayer * - * This file is part of FFmpeg. + * This file is part of Libav. * - * FFmpeg is free software; you can redistribute it and/or + * Libav is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * - * FFmpeg is distributed in the hope that it will be useful, + * Libav is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public - * License along with FFmpeg; if not, write to the Free Software + * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** - * @file libavcodec/bitstream.c + * @file * bitstream api. */ @@ -32,20 +32,18 @@ #include "get_bits.h" #include "put_bits.h" -const uint8_t ff_log2_run[32]={ +const uint8_t ff_log2_run[41]={ 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, - 8, 9,10,11,12,13,14,15 + 8, 9,10,11,12,13,14,15, +16,17,18,19,20,21,22,23, +24, }; -void align_put_bits(PutBitContext *s) +void avpriv_align_put_bits(PutBitContext *s) { -#ifdef ALT_BITSTREAM_WRITER - put_bits(s,( - s->index) & 7,0); -#else put_bits(s,s->bit_left & 7,0); -#endif } void ff_put_string(PutBitContext *pb, const char *string, int terminate_string) @@ -58,7 +56,7 @@ void ff_put_string(PutBitContext *pb, const char *string, int terminate_string) put_bits(pb, 8, 0); } -void ff_copy_bits(PutBitContext *pb, const uint8_t *src, int length) +void avpriv_copy_bits(PutBitContext *pb, const uint8_t *src, int length) { int words= length>>4; int bits= length&15; @@ -81,8 +79,6 @@ void ff_copy_bits(PutBitContext *pb, const uint8_t *src, int length) /* VLC decoding */ -//#define DEBUG_VLC - #define GET_DATA(v, table, i, wrap, size) \ {\ const uint8_t *ptr = (const uint8_t *)table + i * wrap;\ @@ -107,7 +103,7 @@ static int alloc_table(VLC *vlc, int size, int use_static) vlc->table_size += size; if (vlc->table_size > vlc->table_allocated) { if(use_static) - abort(); //cant do anything, init_vlc() is used with too little memory + abort(); // cannot do anything, init_vlc() is used with too little memory vlc->table_allocated += (1 << vlc->bits); vlc->table = av_realloc(vlc->table, sizeof(VLC_TYPE) * 2 * vlc->table_allocated); @@ -118,10 +114,10 @@ static int alloc_table(VLC *vlc, int size, int use_static) } static av_always_inline uint32_t bitswap_32(uint32_t x) { - return av_reverse[x&0xFF]<<24 - | av_reverse[(x>>8)&0xFF]<<16 - | av_reverse[(x>>16)&0xFF]<<8 - | av_reverse[x>>24]; + return (uint32_t)av_reverse[x&0xFF]<<24 + | (uint32_t)av_reverse[(x>>8)&0xFF]<<16 + | (uint32_t)av_reverse[(x>>16)&0xFF]<<8 + | (uint32_t)av_reverse[x>>24]; } typedef struct { @@ -162,82 +158,72 @@ static int build_table(VLC *vlc, int table_nb_bits, int nb_codes, table_size = 1 << table_nb_bits; table_index = alloc_table(vlc, table_size, flags & INIT_VLC_USE_NEW_STATIC); -#ifdef DEBUG_VLC - av_log(NULL,AV_LOG_DEBUG,"new table index=%d size=%d\n", - table_index, table_size); -#endif + av_dlog(NULL, "new table index=%d size=%d\n", table_index, table_size); if (table_index < 0) return -1; table = &vlc->table[table_index]; - for(i=0;i> (32 - table_nb_bits); - nb = 1 << (table_nb_bits - n); - inc = 1; - if (flags & INIT_VLC_LE) { - j = bitswap_32(code); - inc = 1 << n; - } - for(k=0;k> (32 - table_nb_bits); - subtable_bits = n; - codes[i].bits = n; - codes[i].code = code << table_nb_bits; - for (k = i+1; k < nb_codes; k++) { - n = codes[k].bits - table_nb_bits; - if (n <= 0) - break; - code = codes[k].code; - if (code >> (32 - table_nb_bits) != code_prefix) - break; - codes[k].bits = n; - codes[k].code = code << table_nb_bits; - subtable_bits = FFMAX(subtable_bits, n); - } - subtable_bits = FFMIN(subtable_bits, table_nb_bits); - j = (flags & INIT_VLC_LE) ? bitswap_32(code_prefix) >> (32 - table_nb_bits) : code_prefix; - table[j][1] = -subtable_bits; -#ifdef DEBUG_VLC - av_log(NULL,AV_LOG_DEBUG,"%4x: n=%d (subtable)\n", - j, codes[i].bits + table_nb_bits); -#endif - index = build_table(vlc, subtable_bits, k-i, codes+i, flags); - if (index < 0) - return -1; - /* note: realloc has been done, so reload tables */ - table = &vlc->table[table_index]; - table[j][0] = index; //code - i = k-1; + av_dlog(NULL, "i=%d n=%d code=0x%x\n", i, n, code); + if (n <= table_nb_bits) { + /* no need to add another table */ + j = code >> (32 - table_nb_bits); + nb = 1 << (table_nb_bits - n); + inc = 1; + if (flags & INIT_VLC_LE) { + j = bitswap_32(code); + inc = 1 << n; + } + for (k = 0; k < nb; k++) { + av_dlog(NULL, "%4x: code=%d n=%d\n", j, i, n); + if (table[j][1] /*bits*/ != 0) { + av_log(NULL, AV_LOG_ERROR, "incorrect codes\n"); + return -1; } + table[j][1] = n; //bits + table[j][0] = symbol; + j += inc; + } + } else { + /* fill auxiliary table recursively */ + n -= table_nb_bits; + code_prefix = code >> (32 - table_nb_bits); + subtable_bits = n; + codes[i].bits = n; + codes[i].code = code << table_nb_bits; + for (k = i+1; k < nb_codes; k++) { + n = codes[k].bits - table_nb_bits; + if (n <= 0) + break; + code = codes[k].code; + if (code >> (32 - table_nb_bits) != code_prefix) + break; + codes[k].bits = n; + codes[k].code = code << table_nb_bits; + subtable_bits = FFMAX(subtable_bits, n); + } + subtable_bits = FFMIN(subtable_bits, table_nb_bits); + j = (flags & INIT_VLC_LE) ? bitswap_32(code_prefix) >> (32 - table_nb_bits) : code_prefix; + table[j][1] = -subtable_bits; + av_dlog(NULL, "%4x: n=%d (subtable)\n", + j, codes[i].bits + table_nb_bits); + index = build_table(vlc, subtable_bits, k-i, codes+i, flags); + if (index < 0) + return -1; + /* note: realloc has been done, so reload tables */ + table = &vlc->table[table_index]; + table[j][0] = index; //code + i = k-1; + } } return table_index; } @@ -267,16 +253,16 @@ static int build_table(VLC *vlc, int table_nb_bits, int nb_codes, (byte/word/long) to store the 'bits', 'codes', and 'symbols' tables. 'use_static' should be set to 1 for tables, which should be freed - with av_free_static(), 0 if free_vlc() will be used. + with av_free_static(), 0 if ff_free_vlc() will be used. */ -int init_vlc_sparse(VLC *vlc, int nb_bits, int nb_codes, +int ff_init_vlc_sparse(VLC *vlc, int nb_bits, int nb_codes, const void *bits, int bits_wrap, int bits_size, const void *codes, int codes_wrap, int codes_size, const void *symbols, int symbols_wrap, int symbols_size, int flags) { - VLCcode buf[nb_codes]; - int i, j; + VLCcode *buf; + int i, j, ret; vlc->bits = nb_bits; if(flags & INIT_VLC_USE_NEW_STATIC){ @@ -291,9 +277,9 @@ int init_vlc_sparse(VLC *vlc, int nb_bits, int nb_codes, vlc->table_size = 0; } -#ifdef DEBUG_VLC - av_log(NULL,AV_LOG_DEBUG,"build table nb_codes=%d\n", nb_codes); -#endif + av_dlog(NULL, "build table nb_codes=%d\n", nb_codes); + + buf = av_malloc((nb_codes+1)*sizeof(VLCcode)); assert(symbols_size <= 2 || !symbols); j = 0; @@ -319,7 +305,10 @@ int init_vlc_sparse(VLC *vlc, int nb_bits, int nb_codes, COPY(buf[j].bits && buf[j].bits <= nb_bits); nb_codes = j; - if (build_table(vlc, nb_bits, nb_codes, buf, flags) < 0) { + ret = build_table(vlc, nb_bits, nb_codes, buf, flags); + + av_free(buf); + if (ret < 0) { av_freep(&vlc->table); return -1; } @@ -329,8 +318,7 @@ int init_vlc_sparse(VLC *vlc, int nb_bits, int nb_codes, } -void free_vlc(VLC *vlc) +void ff_free_vlc(VLC *vlc) { av_freep(&vlc->table); } -