GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/h261_parser.c Lines: 7 32 21.9 %
Date: 2019-11-18 18:00:01 Branches: 1 20 5.0 %

Line Branch Exec Source
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/*
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 * H.261 parser
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 * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
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 * Copyright (c) 2004 Maarten Daniels
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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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 * H.261 parser
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 */
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#include "parser.h"
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static int h261_find_frame_end(ParseContext *pc, AVCodecContext *avctx,
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                               const uint8_t *buf, int buf_size)
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{
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    int vop_found, i, j;
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    uint32_t state;
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    vop_found = pc->frame_start_found;
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    state     = pc->state;
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    for (i = 0; i < buf_size && !vop_found; i++) {
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        state = (state << 8) | buf[i];
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        for (j = 0; j < 8; j++) {
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            if (((state >> j) & 0xFFFFF0) == 0x000100) {
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                vop_found = 1;
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                break;
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            }
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        }
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    }
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    if (vop_found) {
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        for (; i < buf_size; i++) {
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            state = (state << 8) | buf[i];
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            for (j = 0; j < 8; j++) {
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                if (((state >> j) & 0xFFFFF0) == 0x000100) {
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                    pc->frame_start_found = 0;
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                    pc->state             = (state >> (3 * 8)) + 0xFF00;
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                    return i - 2;
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                }
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            }
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        }
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    }
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    pc->frame_start_found = vop_found;
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    pc->state             = state;
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    return END_NOT_FOUND;
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}
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static int h261_parse(AVCodecParserContext *s,
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                      AVCodecContext *avctx,
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                      const uint8_t **poutbuf, int *poutbuf_size,
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                      const uint8_t *buf, int buf_size)
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{
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    ParseContext *pc = s->priv_data;
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    int next;
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    if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
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        next = buf_size;
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    } else {
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        next = h261_find_frame_end(pc, avctx, buf, buf_size);
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        if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
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            *poutbuf      = NULL;
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            *poutbuf_size = 0;
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            return buf_size;
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        }
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    }
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    *poutbuf      = buf;
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    *poutbuf_size = buf_size;
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    return next;
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}
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AVCodecParser ff_h261_parser = {
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    .codec_ids      = { AV_CODEC_ID_H261 },
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    .priv_data_size = sizeof(ParseContext),
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    .parser_parse   = h261_parse,
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    .parser_close   = ff_parse_close,
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};