GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/wnv1.c Lines: 36 49 73.5 %
Date: 2020-10-23 17:01:47 Branches: 10 18 55.6 %

Line Branch Exec Source
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/*
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 * Winnov WNV1 codec
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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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/**
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 * @file
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 * Winnov WNV1 codec.
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 */
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#define BITSTREAM_READER_LE
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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 const uint16_t code_tab[16][2] = {
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    { 0x17F, 9 }, { 0xBF, 8 }, { 0x5F, 7 }, { 0x2F, 6 }, { 0x17, 5 }, { 0x0B, 4 }, { 0x005, 3 },
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    { 0x000, 1 },
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    { 0x01, 3 }, { 0x03, 4 }, { 0x07, 5 }, { 0x0F, 6 }, { 0x1F, 7 }, { 0x3F, 8 }, { 0x07F, 9 }, { 0xFF, 8 }
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};
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#define CODE_VLC_BITS 9
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static VLC code_vlc;
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/* returns modified base_value */
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3302400
static inline int wnv1_get_code(GetBitContext *gb, int shift, int base_value)
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{
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3302400
    int v = get_vlc2(gb, code_vlc.table, CODE_VLC_BITS, 1);
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3302400
    if (v == 15)
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70676
        return get_bits(gb, 8 - shift) << shift;
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    else
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3231724
        return base_value + ((v - 7U) << shift);
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}
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static int decode_frame(AVCodecContext *avctx,
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                        void *data, int *got_frame,
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                        AVPacket *avpkt)
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{
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    const uint8_t *buf    = avpkt->data;
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    int buf_size          = avpkt->size;
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    AVFrame * const p     = data;
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    GetBitContext gb;
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    unsigned char *Y,*U,*V;
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    int i, j, ret, shift;
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    int prev_y = 0, prev_u = 0, prev_v = 0;
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    if (buf_size < 8 + avctx->height * (avctx->width/2)/8) {
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        av_log(avctx, AV_LOG_ERROR, "Packet size %d is too small\n", buf_size);
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        return AVERROR_INVALIDDATA;
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    }
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    if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
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        return ret;
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    p->key_frame = 1;
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    if ((ret = init_get_bits8(&gb, buf + 8, buf_size - 8)) < 0)
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        return ret;
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    if (buf[2] >> 4 == 6)
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        shift = 2;
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    else {
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        shift = 8 - (buf[2] >> 4);
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        if (shift > 4) {
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            avpriv_request_sample(avctx,
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                                  "Unknown WNV1 frame header value %i",
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                                  buf[2] >> 4);
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            shift = 4;
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        }
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        if (shift < 1) {
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            avpriv_request_sample(avctx,
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                                  "Unknown WNV1 frame header value %i",
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                                  buf[2] >> 4);
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            shift = 1;
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        }
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    }
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    Y = p->data[0];
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    U = p->data[1];
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    V = p->data[2];
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10406
    for (j = 0; j < avctx->height; j++) {
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835920
        for (i = 0; i < avctx->width / 2; i++) {
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825600
            Y[i * 2] = wnv1_get_code(&gb, shift, prev_y);
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825600
            prev_u = U[i] = wnv1_get_code(&gb, shift, prev_u);
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825600
            prev_y = Y[(i * 2) + 1] = wnv1_get_code(&gb, shift, Y[i * 2]);
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825600
            prev_v = V[i] = wnv1_get_code(&gb, shift, prev_v);
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        }
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10320
        Y += p->linesize[0];
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10320
        U += p->linesize[1];
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10320
        V += p->linesize[2];
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    }
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    *got_frame      = 1;
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    return buf_size;
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}
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static av_cold int decode_init(AVCodecContext *avctx)
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{
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    static VLC_TYPE code_table[1 << CODE_VLC_BITS][2];
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    avctx->pix_fmt = AV_PIX_FMT_YUV422P;
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    code_vlc.table           = code_table;
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    code_vlc.table_allocated = 1 << CODE_VLC_BITS;
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    init_vlc(&code_vlc, CODE_VLC_BITS, 16,
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             &code_tab[0][1], 4, 2,
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             &code_tab[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC | INIT_VLC_LE);
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    return 0;
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}
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AVCodec ff_wnv1_decoder = {
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    .name           = "wnv1",
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    .long_name      = NULL_IF_CONFIG_SMALL("Winnov WNV1"),
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    .type           = AVMEDIA_TYPE_VIDEO,
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    .id             = AV_CODEC_ID_WNV1,
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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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};