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			71 lines
		
	
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			71 lines
		
	
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Audio and Video frame extraction
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|  * Copyright (c) 2003 Fabrice Bellard
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|  * Copyright (c) 2003 Michael Niedermayer
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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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| #include "parser.h"
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| #include "aac_ac3_parser.h"
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| #include "adts_header.h"
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| #include "adts_parser.h"
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| #include "get_bits.h"
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| #include "mpeg4audio.h"
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| 
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| static int aac_sync(uint64_t state, AACAC3ParseContext *hdr_info,
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|         int *need_next_header, int *new_frame_start)
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| {
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|     GetBitContext bits;
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|     AACADTSHeaderInfo hdr;
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|     int size;
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|     union {
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|         uint64_t u64;
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|         uint8_t  u8[8 + AV_INPUT_BUFFER_PADDING_SIZE];
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|     } tmp;
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| 
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|     tmp.u64 = av_be2ne64(state);
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|     init_get_bits(&bits, tmp.u8 + 8 - AV_AAC_ADTS_HEADER_SIZE,
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|                   AV_AAC_ADTS_HEADER_SIZE * 8);
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| 
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|     if ((size = ff_adts_header_parse(&bits, &hdr)) < 0)
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|         return 0;
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|     *need_next_header = 0;
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|     *new_frame_start  = 1;
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|     hdr_info->sample_rate = hdr.sample_rate;
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|     hdr_info->channels    = ff_mpeg4audio_channels[hdr.chan_config];
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|     hdr_info->samples     = hdr.samples;
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|     hdr_info->bit_rate    = hdr.bit_rate;
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|     return size;
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| }
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| 
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| static av_cold int aac_parse_init(AVCodecParserContext *s1)
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| {
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|     AACAC3ParseContext *s = s1->priv_data;
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|     s->header_size = AV_AAC_ADTS_HEADER_SIZE;
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|     s->sync = aac_sync;
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|     return 0;
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| }
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| 
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| 
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| AVCodecParser ff_aac_parser = {
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|     .codec_ids      = { AV_CODEC_ID_AAC },
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|     .priv_data_size = sizeof(AACAC3ParseContext),
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|     .parser_init    = aac_parse_init,
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|     .parser_parse   = ff_aac_ac3_parse,
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|     .parser_close   = ff_parse_close,
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| };
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