X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fvorbis.c;h=8ff24ab6277ef8037f02adff35985441bf3e2269;hb=8400b126acb153329c418433c377d96afd1d1e02;hp=2148c23665aef3c44b25674811837fa09c26144b;hpb=9106a698e726c041128a05db0a011caae755d10b;p=ffmpeg diff --git a/libavcodec/vorbis.c b/libavcodec/vorbis.c index 2148c23665a..8ff24ab6277 100644 --- a/libavcodec/vorbis.c +++ b/libavcodec/vorbis.c @@ -1,27 +1,26 @@ -/** - * @file libavcodec/vorbis.c - * Common code for Vorbis I encoder and decoder - * @author Denes Balatoni ( dbalatoni programozo hu ) - - * 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 */ -#undef V_DEBUG -//#define V_DEBUG +/** + * @file + * Common code for Vorbis I encoder and decoder + * @author Denes Balatoni ( dbalatoni programozo hu ) + */ #define ALT_BITSTREAM_READER_LE #include "avcodec.h" @@ -32,100 +31,112 @@ /* Helper functions */ -unsigned int ff_vorbis_nth_root(unsigned int x, unsigned int n) { // x^(1/n) - unsigned int ret=0, i, j; +// x^(1/n) +unsigned int ff_vorbis_nth_root(unsigned int x, unsigned int n) +{ + unsigned int ret = 0, i, j; do { ++ret; - for(i=0,j=ret;i 32 checks should be redundant, all calling code should +// already ensure that, but since it allows overwriting the stack it seems +// reasonable to check redundantly. +int ff_vorbis_len2vlc(uint8_t *bits, uint32_t *codes, unsigned num) +{ + uint32_t exit_at_level[33] = { 404 }; - uint_fast8_t i,j; - uint_fast32_t code,p; + unsigned i, j, p, code; -#ifdef V_DEBUG +#ifdef DEBUG GetBitContext gb; #endif - for(p=0;(bits[p]==0) && (pavccontext, AV_LOG_INFO, "An empty codebook. Heh?! \n"); return 0; } - codes[p]=0; - for(i=0;i 32) + return 1; + for (i = 0; i < bits[p]; ++i) + exit_at_level[i+1] = 1 << i; -#ifdef V_DEBUG - av_log(NULL, AV_LOG_INFO, " %d. of %d code len %d code %d - ", p, num, bits[p], codes[p]); - init_get_bits(&gb, (uint_fast8_t *)&codes[p], bits[p]); - for(i=0;i 32) + return 1; + if (bits[p] == 0) + continue; // find corresponding exit(node which the tree can grow further from) - for(i=bits[p];i>0;--i) { - if (exit_at_level[i]) break; - } - if (!i) return 1; // overspecified tree - code=exit_at_level[i]; - exit_at_level[i]=0; + for (i = bits[p]; i > 0; --i) + if (exit_at_level[i]) + break; + if (!i) // overspecified tree + return 1; + code = exit_at_level[i]; + exit_at_level[i] = 0; // construct code (append 0s to end) and introduce new exits - for(j=i+1;j<=bits[p];++j) { - exit_at_level[j]=code+(1<<(j-1)); - } - codes[p]=code; + for (j = i + 1 ;j <= bits[p]; ++j) + exit_at_level[j] = code + (1 << (j - 1)); + codes[p] = code; -#ifdef V_DEBUG +#ifdef DEBUG av_log(NULL, AV_LOG_INFO, " %d. code len %d code %d - ", p, bits[p], codes[p]); - init_get_bits(&gb, (uint_fast8_t *)&codes[p], bits[p]); - for(i=0;i list[list[i].low].x) list[i].low = j; + if (tmp > list[list[i].low].x) + list[i].low = j; } else { - if (tmp < list[list[i].high].x) list[i].high = j; + if (tmp < list[list[i].high].x) + list[i].high = j; } } } @@ -141,28 +152,60 @@ void ff_vorbis_ready_floor1_list(vorbis_floor1_entry * list, int values) { } } -static void render_line(int x0, int y0, int x1, int y1, float * buf) { - int dy = y1 - y0; - int adx = x1 - x0; - int base = dy / adx; - int ady = FFABS(dy) - FFABS(base) * adx; - int x = x0; - int y = y0; - int err = 0; - int sy = dy<0 ? -1 : 1; - buf[x] = ff_vorbis_floor1_inverse_db_table[y]; - while (++x < x1) { +static inline void render_line_unrolled(intptr_t x, intptr_t y, int x1, + intptr_t sy, int ady, int adx, + float *buf) +{ + int err = -adx; + x -= x1 - 1; + buf += x1 - 1; + while (++x < 0) { err += ady; - if (err >= adx) { - err -= adx; - y += sy; + if (err >= 0) { + err += ady - adx; + y += sy; + buf[x++] = ff_vorbis_floor1_inverse_db_table[y]; } - y += base; buf[x] = ff_vorbis_floor1_inverse_db_table[y]; } + if (x <= 0) { + if (err + ady >= 0) + y += sy; + buf[x] = ff_vorbis_floor1_inverse_db_table[y]; + } +} + +static void render_line(int x0, int y0, int x1, int y1, float *buf) +{ + int dy = y1 - y0; + int adx = x1 - x0; + int ady = FFABS(dy); + int sy = dy < 0 ? -1 : 1; + buf[x0] = ff_vorbis_floor1_inverse_db_table[y0]; + if (ady*2 <= adx) { // optimized common case + render_line_unrolled(x0, y0, x1, sy, ady, adx, buf); + } else { + int base = dy / adx; + int x = x0; + int y = y0; + int err = -adx; + ady -= FFABS(base) * adx; + while (++x < x1) { + y += base; + err += ady; + if (err >= 0) { + err -= adx; + y += sy; + } + buf[x] = ff_vorbis_floor1_inverse_db_table[y]; + } + } } -void ff_vorbis_floor1_render_list(vorbis_floor1_entry * list, int values, uint_fast16_t * y_list, int * flag, int multiplier, float * out, int samples) { +void ff_vorbis_floor1_render_list(vorbis_floor1_entry * list, int values, + uint16_t *y_list, int *flag, + int multiplier, float *out, int samples) +{ int lx, ly, i; lx = 0; ly = y_list[0] * multiplier; @@ -176,7 +219,9 @@ void ff_vorbis_floor1_render_list(vorbis_floor1_entry * list, int values, uint_f lx = x1; ly = y1; } - if (lx >= samples) break; + if (lx >= samples) + break; } - if (lx < samples) render_line(lx, ly, samples, ly, out); + if (lx < samples) + render_line(lx, ly, samples, ly, out); }