Coverage Report

Created: 2025-08-28 07:12

/src/ffmpeg/libavcodec/tmv.c
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Count
Source
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/*
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 * 8088flex TMV video decoder
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 * Copyright (c) 2009 Daniel Verkamp <daniel at drv.nu>
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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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 * 8088flex TMV video decoder
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 * @author Daniel Verkamp
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 * @see http://www.oldskool.org/pc/8088_Corruption
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 */
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#include <string.h>
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#include "avcodec.h"
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#include "codec_internal.h"
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#include "decode.h"
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#include "libavutil/internal.h"
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#include "libavutil/xga_font_data.h"
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#include "cga_data.h"
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static int tmv_decode_frame(AVCodecContext *avctx, AVFrame *frame,
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                            int *got_frame, AVPacket *avpkt)
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295k
{
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295k
    const uint8_t *src = avpkt->data;
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295k
    const uint8_t *cga_font = avpriv_cga_font_get();
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295k
    uint8_t *dst;
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295k
    unsigned char_cols = avctx->width >> 3;
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295k
    unsigned char_rows = avctx->height >> 3;
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295k
    unsigned x, y, fg, bg, c;
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295k
    int ret;
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295k
    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
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95.5k
        return ret;
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200k
    if (avpkt->size < 2*char_rows*char_cols) {
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43.6k
        av_log(avctx, AV_LOG_ERROR,
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43.6k
               "Input buffer too small, truncated sample?\n");
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43.6k
        *got_frame = 0;
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43.6k
        return AVERROR_INVALIDDATA;
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43.6k
    }
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156k
    dst              = frame->data[0];
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156k
    memcpy(frame->data[1], ff_cga_palette, 16 * 4);
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156k
    memset(frame->data[1] + 16 * 4, 0, AVPALETTE_SIZE - 16 * 4);
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12.0M
    for (y = 0; y < char_rows; y++) {
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12.0M
        for (x = 0; x < char_cols; x++) {
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90.5k
            c  = *src++;
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90.5k
            bg = *src  >> 4;
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90.5k
            fg = *src++ & 0xF;
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90.5k
            ff_draw_pc_font(dst + x * 8, frame->linesize[0],
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90.5k
                            cga_font, 8, c, fg, bg);
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90.5k
        }
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11.9M
        dst += frame->linesize[0] * 8;
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11.9M
    }
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156k
    *got_frame = 1;
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156k
    return avpkt->size;
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200k
}
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static av_cold int tmv_decode_init(AVCodecContext *avctx)
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702
{
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702
    avctx->pix_fmt = AV_PIX_FMT_PAL8;
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702
    return 0;
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702
}
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const FFCodec ff_tmv_decoder = {
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    .p.name         = "tmv",
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    CODEC_LONG_NAME("8088flex TMV"),
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    .p.type         = AVMEDIA_TYPE_VIDEO,
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    .p.id           = AV_CODEC_ID_TMV,
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    .init           = tmv_decode_init,
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    FF_CODEC_DECODE_CB(tmv_decode_frame),
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    .p.capabilities = AV_CODEC_CAP_DR1,
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};