GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/ws-snd1.c Lines: 78 89 87.6 %
Date: 2020-10-23 17:01:47 Branches: 32 40 80.0 %

Line Branch Exec Source
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/*
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 * Westwood SNDx codecs
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 * Copyright (c) 2005 Konstantin Shishkov
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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/channel_layout.h"
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#include "libavutil/common.h"
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#include "libavutil/intreadwrite.h"
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#include "avcodec.h"
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#include "internal.h"
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/**
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 * @file
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 * Westwood SNDx codecs
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 *
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 * Reference documents about VQA format and its audio codecs
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 * can be found here:
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 * http://www.multimedia.cx
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 */
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static const int8_t ws_adpcm_4bit[] = {
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    -9, -8, -6, -5, -4, -3, -2, -1,
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     0,  1,  2,  3,  4,  5,  6,  8
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};
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static av_cold int ws_snd_decode_init(AVCodecContext *avctx)
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{
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    avctx->channels       = 1;
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    avctx->channel_layout = AV_CH_LAYOUT_MONO;
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    avctx->sample_fmt     = AV_SAMPLE_FMT_U8;
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    return 0;
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}
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static int ws_snd_decode_frame(AVCodecContext *avctx, void *data,
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                               int *got_frame_ptr, AVPacket *avpkt)
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{
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    AVFrame *frame     = data;
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    const uint8_t *buf = avpkt->data;
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    int buf_size       = avpkt->size;
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    int in_size, out_size, ret;
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    int sample = 128;
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    uint8_t *samples;
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    uint8_t *samples_end;
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    if (!buf_size)
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        return 0;
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    if (buf_size < 4) {
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        av_log(avctx, AV_LOG_ERROR, "packet is too small\n");
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        return AVERROR(EINVAL);
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    }
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    out_size = AV_RL16(&buf[0]);
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    in_size  = AV_RL16(&buf[2]);
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    buf += 4;
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    if (in_size > buf_size) {
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        av_log(avctx, AV_LOG_ERROR, "Frame data is larger than input buffer\n");
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        return AVERROR_INVALIDDATA;
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    }
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    /* get output buffer */
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    frame->nb_samples = out_size;
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    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
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        return ret;
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    samples     = frame->data[0];
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    samples_end = samples + out_size;
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    if (in_size == out_size) {
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        memcpy(samples, buf, out_size);
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        *got_frame_ptr = 1;
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        return buf_size;
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    }
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    while (samples < samples_end && buf - avpkt->data < buf_size) {
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        int code, smp, size;
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        uint8_t count;
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        code  = *buf >> 6;
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8529
        count = *buf & 0x3F;
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8529
        buf++;
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        /* make sure we don't write past the output buffer */
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        switch (code) {
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        case 0:  smp = 4 * (count + 1);                break;
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2919
        case 1:  smp = 2 * (count + 1);                break;
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5585
        case 2:  smp = (count & 0x20) ? 1 : count + 1; break;
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        default: smp = count + 1;                      break;
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        }
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8529
        if (samples_end - samples < smp)
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            break;
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        /* make sure we don't read past the input buffer */
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        size = ((code == 2 && (count & 0x20)) || code == 3) ? 0 : count + 1;
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8529
        if ((buf - avpkt->data) + size > buf_size)
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            break;
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        switch (code) {
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        case 0: /* ADPCM 2-bit */
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            for (count++; count > 0; count--) {
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                code = *buf++;
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                sample += ( code       & 0x3) - 2;
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                sample = av_clip_uint8(sample);
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                *samples++ = sample;
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                sample += ((code >> 2) & 0x3) - 2;
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                sample = av_clip_uint8(sample);
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                *samples++ = sample;
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                sample += ((code >> 4) & 0x3) - 2;
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                sample = av_clip_uint8(sample);
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                *samples++ = sample;
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                sample +=  (code >> 6)        - 2;
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                sample = av_clip_uint8(sample);
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                *samples++ = sample;
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            }
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            break;
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        case 1: /* ADPCM 4-bit */
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            for (count++; count > 0; count--) {
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                code = *buf++;
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                sample += ws_adpcm_4bit[code & 0xF];
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                sample = av_clip_uint8(sample);
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                *samples++ = sample;
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                sample += ws_adpcm_4bit[code >> 4];
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                sample = av_clip_uint8(sample);
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                *samples++ = sample;
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            }
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            break;
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        case 2: /* no compression */
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            if (count & 0x20) { /* big delta */
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                int8_t t;
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                t = count;
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                t <<= 3;
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                sample += t >> 3;
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                sample = av_clip_uint8(sample);
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                *samples++ = sample;
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            } else { /* copy */
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                memcpy(samples, buf, smp);
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                samples += smp;
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                buf     += smp;
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                sample = buf[-1];
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            }
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5585
            break;
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        default: /* run */
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            memset(samples, sample, smp);
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            samples += smp;
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        }
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    }
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    frame->nb_samples = samples - frame->data[0];
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    *got_frame_ptr    = 1;
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    return buf_size;
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}
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AVCodec ff_ws_snd1_decoder = {
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    .name           = "ws_snd1",
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    .long_name      = NULL_IF_CONFIG_SMALL("Westwood Audio (SND1)"),
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    .type           = AVMEDIA_TYPE_AUDIO,
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    .id             = AV_CODEC_ID_WESTWOOD_SND1,
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    .init           = ws_snd_decode_init,
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    .decode         = ws_snd_decode_frame,
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    .capabilities   = AV_CODEC_CAP_DR1,
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};