GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/vima.c Lines: 67 71 94.4 %
Date: 2020-08-14 10:39:37 Branches: 30 38 78.9 %

Line Branch Exec Source
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/*
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 * LucasArts VIMA decoder
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 * Copyright (c) 2012 Paul B Mahol
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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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 * LucasArts VIMA audio decoder
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 * @author Paul B Mahol
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 */
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#include "libavutil/channel_layout.h"
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#include "adpcm_data.h"
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#include "avcodec.h"
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#include "get_bits.h"
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#include "internal.h"
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static int predict_table_init = 0;
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static uint16_t predict_table[5786 * 2];
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static const uint8_t size_table[] = {
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    4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
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    4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
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    4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
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    5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
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    6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
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    7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7
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};
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static const int8_t index_table1[] = {
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    -1, 4, -1, 4
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};
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static const int8_t index_table2[] = {
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    -1, -1, 2, 6, -1, -1, 2, 6
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};
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static const int8_t index_table3[] = {
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    -1, -1, -1, -1, 1, 2, 4, 6, -1, -1, -1, -1, 1, 2, 4, 6
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};
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static const int8_t index_table4[] = {
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    -1, -1, -1, -1, -1, -1, -1, -1, 1,  1,  1,  2,  2,  4,  5,  6,
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    -1, -1, -1, -1, -1, -1, -1, -1, 1,  1,  1,  2,  2,  4,  5,  6
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};
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static const int8_t index_table5[] = {
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    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
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     1,  1,  1,  1,  1,  2,  2,  2,  2,  4,  4,  4,  5,  5,  6,  6,
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    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
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     1,  1,  1,  1,  1,  2,  2,  2,  2,  4,  4,  4,  5,  5,  6,  6
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};
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static const int8_t index_table6[] = {
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    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
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    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
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     1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  2,  2,  2,  2,  2,  2,
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     2,  2,  4,  4,  4,  4,  4,  4,  5,  5,  5,  5,  6,  6,  6,  6,
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    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
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    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
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     1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  2,  2,  2,  2,  2,  2,
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     2,  2,  4,  4,  4,  4,  4,  4,  5,  5,  5,  5,  6,  6,  6,  6
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};
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static const int8_t *const step_index_tables[] = {
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    index_table1, index_table2, index_table3,
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    index_table4, index_table5, index_table6
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};
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static av_cold int decode_init(AVCodecContext *avctx)
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{
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    int start_pos;
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3
    avctx->sample_fmt = AV_SAMPLE_FMT_S16;
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3
    if (predict_table_init)
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1
        return 0;
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    for (start_pos = 0; start_pos < 64; start_pos++) {
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        unsigned int dest_pos, table_pos;
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11520
        for (table_pos = 0, dest_pos = start_pos;
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             table_pos < FF_ARRAY_ELEMS(ff_adpcm_step_table);
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11392
             table_pos++, dest_pos += 64) {
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11392
            int put = 0, count, table_value;
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11392
            table_value = ff_adpcm_step_table[table_pos];
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79744
            for (count = 32; count != 0; count >>= 1) {
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68352
                if (start_pos & count)
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34176
                    put += table_value;
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68352
                table_value >>= 1;
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            }
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11392
            predict_table[dest_pos] = put;
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        }
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    }
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2
    predict_table_init = 1;
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2
    return 0;
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}
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static int decode_frame(AVCodecContext *avctx, void *data,
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                        int *got_frame_ptr, AVPacket *pkt)
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{
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    GetBitContext gb;
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    AVFrame *frame = data;
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    int16_t pcm_data[2];
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    uint32_t samples;
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    int8_t channel_hint[2];
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    int ret, chan;
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16
    int channels = 1;
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    if (pkt->size < 13)
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        return AVERROR_INVALIDDATA;
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    if ((ret = init_get_bits8(&gb, pkt->data, pkt->size)) < 0)
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        return ret;
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    samples = get_bits_long(&gb, 32);
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16
    if (samples == 0xffffffff) {
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16
        skip_bits_long(&gb, 32);
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16
        samples = get_bits_long(&gb, 32);
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    }
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    if (samples > pkt->size * 2)
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        return AVERROR_INVALIDDATA;
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    channel_hint[0] = get_sbits(&gb, 8);
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16
    if (channel_hint[0] & 0x80) {
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16
        channel_hint[0] = ~channel_hint[0];
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16
        channels = 2;
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    }
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16
    avctx->channels = channels;
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16
    avctx->channel_layout = (channels == 2) ? AV_CH_LAYOUT_STEREO
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16
                                            : AV_CH_LAYOUT_MONO;
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16
    pcm_data[0] = get_sbits(&gb, 16);
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16
    if (channels > 1) {
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16
        channel_hint[1] = get_sbits(&gb, 8);
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16
        pcm_data[1]     = get_sbits(&gb, 16);
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    }
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16
    frame->nb_samples = samples;
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16
    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
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        return ret;
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    for (chan = 0; chan < channels; chan++) {
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        uint16_t *dest = (uint16_t *)frame->data[0] + chan;
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        int step_index = channel_hint[chan];
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        int output = pcm_data[chan];
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        int sample;
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191132
        for (sample = 0; sample < samples; sample++) {
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            int lookup_size, lookup, highbit, lowbits;
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191100
            step_index  = av_clip(step_index, 0, 88);
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191100
            lookup_size = size_table[step_index];
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191100
            lookup      = get_bits(&gb, lookup_size);
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191100
            highbit     = 1 << (lookup_size - 1);
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191100
            lowbits     = highbit - 1;
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191100
            if (lookup & highbit)
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93134
                lookup ^= highbit;
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            else
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97966
                highbit = 0;
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191100
            if (lookup == lowbits) {
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8197
                output = get_sbits(&gb, 16);
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            } else {
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                int predict_index, diff;
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182903
                predict_index = (lookup << (7 - lookup_size)) | (step_index << 6);
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182903
                predict_index = av_clip(predict_index, 0, 5785);
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182903
                diff          = predict_table[predict_index];
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182903
                if (lookup)
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153682
                    diff += ff_adpcm_step_table[step_index] >> (lookup_size - 1);
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182903
                if (highbit)
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89050
                    diff = -diff;
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182903
                output = av_clip_int16(output + diff);
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            }
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191100
            *dest = output;
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191100
            dest += channels;
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191100
            step_index += step_index_tables[lookup_size - 2][lookup];
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        }
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    }
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16
    *got_frame_ptr = 1;
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16
    return pkt->size;
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}
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AVCodec ff_adpcm_vima_decoder = {
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    .name         = "adpcm_vima",
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    .long_name    = NULL_IF_CONFIG_SMALL("LucasArts VIMA audio"),
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    .type         = AVMEDIA_TYPE_AUDIO,
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    .id           = AV_CODEC_ID_ADPCM_VIMA,
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    .init         = decode_init,
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    .decode       = decode_frame,
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    .capabilities = AV_CODEC_CAP_DR1,
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};