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			81 lines
		
	
	
	
		
			2.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			81 lines
		
	
	
	
		
			2.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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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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| #ifndef AVUTIL_TX_H
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| #define AVUTIL_TX_H
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| 
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| #include <stdint.h>
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| #include <stddef.h>
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| 
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| typedef struct AVTXContext AVTXContext;
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| 
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| typedef struct AVComplexFloat {
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|     float re, im;
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| } AVComplexFloat;
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| 
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| enum AVTXType {
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|     /**
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|      * Standard complex to complex FFT with sample data type AVComplexFloat.
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|      * Scaling currently unsupported
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|      */
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|     AV_TX_FLOAT_FFT = 0,
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|     /**
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|      * Standard MDCT with sample data type of float and a scale type of
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|      * float. Length is the frame size, not the window size (which is 2x frame)
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|      */
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|     AV_TX_FLOAT_MDCT = 1,
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| };
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| 
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| /**
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|  * Function pointer to a function to perform the transform.
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|  *
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|  * @note Using a different context than the one allocated during av_tx_init()
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|  * is not allowed.
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|  *
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|  * @param s the transform context
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|  * @param out the output array
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|  * @param in the input array
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|  * @param stride the input or output stride (depending on transform direction)
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|  * in bytes, currently implemented for all MDCT transforms
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|  */
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| typedef void (*av_tx_fn)(AVTXContext *s, void *out, void *in, ptrdiff_t stride);
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| 
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| /**
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|  * Initialize a transform context with the given configuration
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|  * Currently power of two lengths from 4 to 131072 are supported, along with
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|  * any length decomposable to a power of two and either 3, 5 or 15.
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|  *
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|  * @param ctx the context to allocate, will be NULL on error
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|  * @param tx pointer to the transform function pointer to set
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|  * @param type type the type of transform
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|  * @param inv whether to do an inverse or a forward transform
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|  * @param len the size of the transform in samples
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|  * @param scale pointer to the value to scale the output if supported by type
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|  * @param flags currently unused
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|  *
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|  * @return 0 on success, negative error code on failure
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|  */
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| int av_tx_init(AVTXContext **ctx, av_tx_fn *tx, enum AVTXType type,
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|                int inv, int len, const void *scale, uint64_t flags);
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| 
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| /**
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|  * Frees a context and sets ctx to NULL, does nothing when ctx == NULL
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|  */
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| void av_tx_uninit(AVTXContext **ctx);
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| 
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| #endif /* AVUTIL_TX_H */
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