90 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			90 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * Copyright (c) 2012  Justin Ruggles
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 *
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 * This file is part of Libav.
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 *
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 * Libav 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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 * Libav 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 Libav; 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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 * GSM audio parser
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 *
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 * Splits packets into individual blocks.
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 */
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#include "parser.h"
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#include "gsm.h"
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typedef struct GSMParseContext {
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    ParseContext pc;
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    int block_size;
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    int duration;
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    int remaining;
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} GSMParseContext;
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static int gsm_parse(AVCodecParserContext *s1, 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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    GSMParseContext *s = s1->priv_data;
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    ParseContext *pc = &s->pc;
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    int next;
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    if (!s->block_size) {
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        switch (avctx->codec_id) {
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        case CODEC_ID_GSM:
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            s->block_size = GSM_BLOCK_SIZE;
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            s->duration   = GSM_FRAME_SIZE;
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            break;
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        case CODEC_ID_GSM_MS:
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            s->block_size = GSM_MS_BLOCK_SIZE;
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            s->duration   = GSM_FRAME_SIZE * 2;
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            break;
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        default:
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            return AVERROR(EINVAL);
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        }
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    }
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    if (!s->remaining)
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        s->remaining = s->block_size;
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    if (s->remaining <= buf_size) {
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        next = s->remaining;
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        s->remaining = 0;
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    } else {
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        next = END_NOT_FOUND;
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        s->remaining -= buf_size;
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    }
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    if (ff_combine_frame(pc, next, &buf, &buf_size) < 0 || !buf_size) {
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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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    s1->duration = s->duration;
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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_gsm_parser = {
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    .codec_ids      = { CODEC_ID_GSM, CODEC_ID_GSM_MS },
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    .priv_data_size = sizeof(GSMParseContext),
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    .parser_parse   = gsm_parse,
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    .parser_close   = ff_parse_close,
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};
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