mirror of
				https://github.com/nyanmisaka/ffmpeg-rockchip.git
				synced 2025-10-31 20:42:49 +08:00 
			
		
		
		
	 6410397600
			
		
	
	6410397600
	
	
	
		
			
			Based partially on implementation by Michael Niedermayer <michaelni@gmx.at> in libswresample in FFmpeg. See commits:7f1ae79d3824ab1abfb6
		
			
				
	
	
		
			103 lines
		
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			103 lines
		
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * Copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
 | |
|  *
 | |
|  * This file is part of Libav.
 | |
|  *
 | |
|  * Libav is free software; you can redistribute it and/or
 | |
|  * modify it under the terms of the GNU Lesser General Public
 | |
|  * License as published by the Free Software Foundation; either
 | |
|  * version 2.1 of the License, or (at your option) any later version.
 | |
|  *
 | |
|  * Libav is distributed in the hope that it will be useful,
 | |
|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
 | |
|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 | |
|  * Lesser General Public License for more details.
 | |
|  *
 | |
|  * You should have received a copy of the GNU Lesser General Public
 | |
|  * License along with Libav; if not, write to the Free Software
 | |
|  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 | |
|  */
 | |
| 
 | |
| #if defined(CONFIG_RESAMPLE_DBL)
 | |
| #define SET_TYPE(func)  func ## _dbl
 | |
| #define FELEM         double
 | |
| #define FELEM2        double
 | |
| #define FELEML        double
 | |
| #define OUT(d, v) d = v
 | |
| #define DBL_TO_FELEM(d, v) d = v
 | |
| #elif defined(CONFIG_RESAMPLE_FLT)
 | |
| #define SET_TYPE(func)  func ## _flt
 | |
| #define FELEM         float
 | |
| #define FELEM2        float
 | |
| #define FELEML        float
 | |
| #define OUT(d, v) d = v
 | |
| #define DBL_TO_FELEM(d, v) d = v
 | |
| #elif defined(CONFIG_RESAMPLE_S32)
 | |
| #define SET_TYPE(func)  func ## _s32
 | |
| #define FELEM         int32_t
 | |
| #define FELEM2        int64_t
 | |
| #define FELEML        int64_t
 | |
| #define OUT(d, v) d = av_clipl_int32((v + (1 << 29)) >> 30)
 | |
| #define DBL_TO_FELEM(d, v) d = av_clipl_int32(llrint(v * (1 << 30)));
 | |
| #else
 | |
| #define SET_TYPE(func)  func ## _s16
 | |
| #define FELEM         int16_t
 | |
| #define FELEM2        int32_t
 | |
| #define FELEML        int64_t
 | |
| #define OUT(d, v) d = av_clip_int16((v + (1 << 14)) >> 15)
 | |
| #define DBL_TO_FELEM(d, v) d = av_clip_int16(lrint(v * (1 << 15)))
 | |
| #endif
 | |
| 
 | |
| static void SET_TYPE(resample_one)(ResampleContext *c, int no_filter,
 | |
|                                    void *dst0, int dst_index, const void *src0,
 | |
|                                    int src_size, int index, int frac)
 | |
| {
 | |
|     FELEM *dst = dst0;
 | |
|     const FELEM *src = src0;
 | |
| 
 | |
|     if (no_filter) {
 | |
|         dst[dst_index] = src[index];
 | |
|     } else {
 | |
|         int i;
 | |
|         int sample_index = index >> c->phase_shift;
 | |
|         FELEM2 val = 0;
 | |
|         FELEM *filter = ((FELEM *)c->filter_bank) +
 | |
|                         c->filter_length * (index & c->phase_mask);
 | |
| 
 | |
|         if (sample_index < 0) {
 | |
|             for (i = 0; i < c->filter_length; i++)
 | |
|                 val += src[FFABS(sample_index + i) % src_size] *
 | |
|                        (FELEM2)filter[i];
 | |
|         } else if (c->linear) {
 | |
|             FELEM2 v2 = 0;
 | |
|             for (i = 0; i < c->filter_length; i++) {
 | |
|                 val += src[abs(sample_index + i)] * (FELEM2)filter[i];
 | |
|                 v2  += src[abs(sample_index + i)] * (FELEM2)filter[i + c->filter_length];
 | |
|             }
 | |
|             val += (v2 - val) * (FELEML)frac / c->src_incr;
 | |
|         } else {
 | |
|             for (i = 0; i < c->filter_length; i++)
 | |
|                 val += src[sample_index + i] * (FELEM2)filter[i];
 | |
|         }
 | |
| 
 | |
|         OUT(dst[dst_index], val);
 | |
|     }
 | |
| }
 | |
| 
 | |
| static void SET_TYPE(set_filter)(void *filter0, double *tab, int phase,
 | |
|                                  int tap_count)
 | |
| {
 | |
|     int i;
 | |
|     FELEM *filter = ((FELEM *)filter0) + phase * tap_count;
 | |
|     for (i = 0; i < tap_count; i++) {
 | |
|         DBL_TO_FELEM(filter[i], tab[i]);
 | |
|     }
 | |
| }
 | |
| 
 | |
| #undef SET_TYPE
 | |
| #undef FELEM
 | |
| #undef FELEM2
 | |
| #undef FELEML
 | |
| #undef OUT
 | |
| #undef DBL_TO_FELEM
 |