GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/mjpegdec_common.c Lines: 14 14 100.0 %
Date: 2021-04-20 04:37:23 Branches: 10 10 100.0 %

Line Branch Exec Source
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/*
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 * MJPEG decoder VLC code
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 * Copyright (c) 2000, 2001 Fabrice Bellard
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 * Copyright (c) 2003 Alex Beregszaszi
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 * Copyright (c) 2003-2004 Michael Niedermayer
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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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#include <stdint.h>
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#include "libavutil/avassert.h"
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#include "mjpegdec.h"
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#include "vlc.h"
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static int build_huffman_codes(uint8_t *huff_size, const uint8_t *bits_table)
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{
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    int nb_codes = 0;
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249645
    for (int i = 1, j = 0; i <= 16; i++) {
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        nb_codes += bits_table[i];
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        av_assert1(nb_codes <= 256);
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        for (; j < nb_codes; j++)
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            huff_size[j] = i;
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    }
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    return nb_codes;
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}
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int ff_mjpeg_build_vlc(VLC *vlc, const uint8_t *bits_table,
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                       const uint8_t *val_table, int is_ac, void *logctx)
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{
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    uint8_t huff_size[256];
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    uint16_t huff_sym[256];
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    int nb_codes = build_huffman_codes(huff_size, bits_table);
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    for (int i = 0; i < nb_codes; i++) {
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        huff_sym[i] = val_table[i] + 16 * is_ac;
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        if (is_ac && !val_table[i])
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            huff_sym[i] = 16 * 256;
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    }
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    return ff_init_vlc_from_lengths(vlc, 9, nb_codes, huff_size, 1,
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                                    huff_sym, 2, 2, 0, 0, logctx);
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}