GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/lagarithrac.c Lines: 16 16 100.0 %
Date: 2019-11-18 18:00:01 Branches: 4 4 100.0 %

Line Branch Exec Source
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/*
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 * Lagarith range decoder
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 * Copyright (c) 2009 Nathan Caldwell <saintdev (at) gmail.com>
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 * Copyright (c) 2009 David Conrad
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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/**
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 * @file
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 * Lagarith range decoder
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 * @author Nathan Caldwell
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 * @author David Conrad
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 */
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#include "get_bits.h"
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#include "lagarithrac.h"
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void ff_lag_rac_init(lag_rac *l, GetBitContext *gb, int length)
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{
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    int i, j, left;
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    /* According to reference decoder "1st byte is garbage",
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     * however, it gets skipped by the call to align_get_bits()
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     */
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    align_get_bits(gb);
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    left                = get_bits_left(gb) >> 3;
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    l->bytestream_start =
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    l->bytestream       = gb->buffer + get_bits_count(gb) / 8;
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    l->bytestream_end   = l->bytestream_start + left;
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    l->range        = 0x80;
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    l->low          = *l->bytestream >> 1;
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    l->hash_shift   = FFMAX(l->scale, 10) - 10;
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    l->overread     = 0;
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    for (i = j = 0; i < 1024; i++) {
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        unsigned r = i << l->hash_shift;
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        while (l->prob[j + 1] <= r)
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            j++;
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        l->range_hash[i] = j;
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    }
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}