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			53 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			53 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * RAW MPEG-4 video demuxer
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|  * Copyright (c) 2006  Thijs Vermeir <thijs.vermeir@barco.com>
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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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| #include "avformat.h"
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| #include "rawdec.h"
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| 
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| #define VISUAL_OBJECT_START_CODE       0x000001b5
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| #define VOP_START_CODE                 0x000001b6
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| 
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| static int mpeg4video_probe(AVProbeData *probe_packet)
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| {
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|     uint32_t temp_buffer= -1;
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|     int VO=0, VOL=0, VOP = 0, VISO = 0, res=0;
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|     int i;
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| 
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|     for(i=0; i<probe_packet->buf_size; i++){
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|         temp_buffer = (temp_buffer<<8) + probe_packet->buf[i];
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|         if ((temp_buffer & 0xffffff00) != 0x100)
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|             continue;
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| 
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|         if (temp_buffer == VOP_START_CODE)                         VOP++;
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|         else if (temp_buffer == VISUAL_OBJECT_START_CODE)          VISO++;
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|         else if (temp_buffer < 0x120)                              VO++;
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|         else if (temp_buffer < 0x130)                              VOL++;
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|         else if (   !(0x1AF < temp_buffer && temp_buffer < 0x1B7)
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|                  && !(0x1B9 < temp_buffer && temp_buffer < 0x1C4)) res++;
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|     }
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| 
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|     if (VOP >= VISO && VOP >= VOL && VO >= VOL && VOL > 0 && res==0)
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|         return AVPROBE_SCORE_MAX/2;
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|     return 0;
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| }
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| 
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| FF_DEF_RAWVIDEO_DEMUXER(m4v, "raw MPEG-4 video format", mpeg4video_probe, "m4v", CODEC_ID_MPEG4)
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