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			93 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			93 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * VC-1 and WMV3 decoder
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|  * Copyright (c) 2006-2007 Konstantin Shishkov
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|  * Partly based on vc9.c (c) 2005 Anonymous, Alex Beregszaszi, Michael Niedermayer
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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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| #ifndef AVCODEC_VC1_COMMON_H
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| #define AVCODEC_VC1_COMMON_H
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| 
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| #include <stdint.h>
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| 
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| #include "libavutil/attributes.h"
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| 
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| /** Markers used in VC-1 AP frame data */
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| //@{
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| enum VC1Code {
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|     VC1_CODE_RES0       = 0x00000100,
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|     VC1_CODE_ENDOFSEQ   = 0x0000010A,
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|     VC1_CODE_SLICE,
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|     VC1_CODE_FIELD,
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|     VC1_CODE_FRAME,
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|     VC1_CODE_ENTRYPOINT,
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|     VC1_CODE_SEQHDR,
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| };
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| //@}
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| 
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| #define IS_MARKER(x) (((x) & ~0xFF) == VC1_CODE_RES0)
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| 
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| /** Available Profiles */
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| //@{
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| enum Profile {
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|     PROFILE_SIMPLE,
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|     PROFILE_MAIN,
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|     PROFILE_COMPLEX, ///< TODO: WMV9 specific
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|     PROFILE_ADVANCED
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| };
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| //@}
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| 
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| /** Find VC-1 marker in buffer
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|  * @return position where next marker starts or end of buffer if no marker found
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|  */
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| static av_always_inline const uint8_t* find_next_marker(const uint8_t *src, const uint8_t *end)
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| {
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|     uint32_t mrk = 0xFFFFFFFF;
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| 
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|     if (end-src < 4)
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|         return end;
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|     while (src < end) {
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|         mrk = (mrk << 8) | *src++;
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|         if (IS_MARKER(mrk))
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|             return src - 4;
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|     }
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|     return end;
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| }
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| 
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| static av_always_inline int vc1_unescape_buffer(const uint8_t *src, int size, uint8_t *dst)
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| {
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|     int dsize = 0, i;
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| 
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|     if (size < 4) {
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|         for (dsize = 0; dsize < size; dsize++)
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|             *dst++ = *src++;
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|         return size;
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|     }
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|     for (i = 0; i < size; i++, src++) {
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|         if (src[0] == 3 && i >= 2 && !src[-1] && !src[-2] && i < size-1 && src[1] < 4) {
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|             dst[dsize++] = src[1];
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|             src++;
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|             i++;
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|         } else
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|             dst[dsize++] = *src;
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|     }
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|     return dsize;
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| }
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| 
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| #endif /* AVCODEC_VC1_COMMON_H */
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