diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/pulsecore/ffmpeg/avcodec.h | 71 | ||||
| -rw-r--r-- | src/pulsecore/ffmpeg/dsputil.h | 1 | ||||
| -rw-r--r-- | src/pulsecore/ffmpeg/resample2.c | 324 | 
3 files changed, 396 insertions, 0 deletions
diff --git a/src/pulsecore/ffmpeg/avcodec.h b/src/pulsecore/ffmpeg/avcodec.h new file mode 100644 index 00000000..775ec962 --- /dev/null +++ b/src/pulsecore/ffmpeg/avcodec.h @@ -0,0 +1,71 @@ +/* + * copyright (c) 2001 Fabrice Bellard + * + * This file is part of FFmpeg. + * + * FFmpeg 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. + * + * FFmpeg 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 FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#ifndef AVCODEC_H +#define AVCODEC_H + +/* Just a heavily bastardized version of the original file from + * ffmpeg, just enough to get resample2.c to compile without + * modification -- Lennart */ + +#include <sys/types.h> +#include <inttypes.h> +#include <math.h> +#include <string.h> +#include <stdlib.h> +#include <assert.h> + +#define av_mallocz(l) calloc(1, (l)) +#define av_malloc(l) malloc(l) +#define av_realloc(p,l) realloc((p),(l)) +#define av_free(p) free(p) + +static inline void av_freep(void *k) { +    void **p = k; +     +    if (p) { +        free(*p); +        *p = NULL; +    } +} + +static inline int av_clip(int a, int amin, int amax) +{ +    if (a < amin)      return amin; +    else if (a > amax) return amax; +    else               return a; +} + +#define av_log(a,b,c) + +#define FFABS(a) ((a) >= 0 ? (a) : (-(a))) +#define FFSIGN(a) ((a) > 0 ? 1 : -1) + +#define FFMAX(a,b) ((a) > (b) ? (a) : (b)) +#define FFMIN(a,b) ((a) > (b) ? (b) : (a)) + +struct AVResampleContext; +struct AVResampleContext *av_resample_init(int out_rate, int in_rate, int filter_length, int log2_phase_count, int linear, double cutoff); +int av_resample(struct AVResampleContext *c, short *dst, short *src, int *consumed, int src_size, int dst_size, int update_ctx); +void av_resample_compensate(struct AVResampleContext *c, int sample_delta, int compensation_distance); +void av_resample_close(struct AVResampleContext *c); +void av_build_filter(int16_t *filter, double factor, int tap_count, int phase_count, int scale, int type); + +#endif /* AVCODEC_H */ diff --git a/src/pulsecore/ffmpeg/dsputil.h b/src/pulsecore/ffmpeg/dsputil.h new file mode 100644 index 00000000..8da742d0 --- /dev/null +++ b/src/pulsecore/ffmpeg/dsputil.h @@ -0,0 +1 @@ +/* empty file, just here to allow us to compile an unmodified resampler2.c */ diff --git a/src/pulsecore/ffmpeg/resample2.c b/src/pulsecore/ffmpeg/resample2.c new file mode 100644 index 00000000..da1443d9 --- /dev/null +++ b/src/pulsecore/ffmpeg/resample2.c @@ -0,0 +1,324 @@ +/* + * audio resampling + * Copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at> + * + * This file is part of FFmpeg. + * + * FFmpeg 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. + * + * FFmpeg 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 FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/** + * @file resample2.c + * audio resampling + * @author Michael Niedermayer <michaelni@gmx.at> + */ + +#include "avcodec.h" +#include "dsputil.h" + +#ifndef CONFIG_RESAMPLE_HP +#define FILTER_SHIFT 15 + +#define FELEM int16_t +#define FELEM2 int32_t +#define FELEML int64_t +#define FELEM_MAX INT16_MAX +#define FELEM_MIN INT16_MIN +#define WINDOW_TYPE 9 +#elif !defined(CONFIG_RESAMPLE_AUDIOPHILE_KIDDY_MODE) +#define FILTER_SHIFT 30 + +#define FELEM int32_t +#define FELEM2 int64_t +#define FELEML int64_t +#define FELEM_MAX INT32_MAX +#define FELEM_MIN INT32_MIN +#define WINDOW_TYPE 12 +#else +#define FILTER_SHIFT 0 + +#define FELEM double +#define FELEM2 double +#define FELEML double +#define WINDOW_TYPE 24 +#endif + + +typedef struct AVResampleContext{ +    FELEM *filter_bank; +    int filter_length; +    int ideal_dst_incr; +    int dst_incr; +    int index; +    int frac; +    int src_incr; +    int compensation_distance; +    int phase_shift; +    int phase_mask; +    int linear; +}AVResampleContext; + +/** + * 0th order modified bessel function of the first kind. + */ +static double bessel(double x){ +    double v=1; +    double t=1; +    int i; + +    x= x*x/4; +    for(i=1; i<50; i++){ +        t *= x/(i*i); +        v += t; +    } +    return v; +} + +/** + * builds a polyphase filterbank. + * @param factor resampling factor + * @param scale wanted sum of coefficients for each filter + * @param type 0->cubic, 1->blackman nuttall windowed sinc, 2..16->kaiser windowed sinc beta=2..16 + */ +void av_build_filter(FELEM *filter, double factor, int tap_count, int phase_count, int scale, int type){ +    int ph, i; +    double x, y, w, tab[tap_count]; +    const int center= (tap_count-1)/2; + +    /* if upsampling, only need to interpolate, no filter */ +    if (factor > 1.0) +        factor = 1.0; + +    for(ph=0;ph<phase_count;ph++) { +        double norm = 0; +        for(i=0;i<tap_count;i++) { +            x = M_PI * ((double)(i - center) - (double)ph / phase_count) * factor; +            if (x == 0) y = 1.0; +            else        y = sin(x) / x; +            switch(type){ +            case 0:{ +                const float d= -0.5; //first order derivative = -0.5 +                x = fabs(((double)(i - center) - (double)ph / phase_count) * factor); +                if(x<1.0) y= 1 - 3*x*x + 2*x*x*x + d*(            -x*x + x*x*x); +                else      y=                       d*(-4 + 8*x - 5*x*x + x*x*x); +                break;} +            case 1: +                w = 2.0*x / (factor*tap_count) + M_PI; +                y *= 0.3635819 - 0.4891775 * cos(w) + 0.1365995 * cos(2*w) - 0.0106411 * cos(3*w); +                break; +            default: +                w = 2.0*x / (factor*tap_count*M_PI); +                y *= bessel(type*sqrt(FFMAX(1-w*w, 0))); +                break; +            } + +            tab[i] = y; +            norm += y; +        } + +        /* normalize so that an uniform color remains the same */ +        for(i=0;i<tap_count;i++) { +#ifdef CONFIG_RESAMPLE_AUDIOPHILE_KIDDY_MODE +            filter[ph * tap_count + i] = tab[i] / norm; +#else +            filter[ph * tap_count + i] = av_clip(lrintf(tab[i] * scale / norm), FELEM_MIN, FELEM_MAX); +#endif +        } +    } +#if 0 +    { +#define LEN 1024 +        int j,k; +        double sine[LEN + tap_count]; +        double filtered[LEN]; +        double maxff=-2, minff=2, maxsf=-2, minsf=2; +        for(i=0; i<LEN; i++){ +            double ss=0, sf=0, ff=0; +            for(j=0; j<LEN+tap_count; j++) +                sine[j]= cos(i*j*M_PI/LEN); +            for(j=0; j<LEN; j++){ +                double sum=0; +                ph=0; +                for(k=0; k<tap_count; k++) +                    sum += filter[ph * tap_count + k] * sine[k+j]; +                filtered[j]= sum / (1<<FILTER_SHIFT); +                ss+= sine[j + center] * sine[j + center]; +                ff+= filtered[j] * filtered[j]; +                sf+= sine[j + center] * filtered[j]; +            } +            ss= sqrt(2*ss/LEN); +            ff= sqrt(2*ff/LEN); +            sf= 2*sf/LEN; +            maxff= FFMAX(maxff, ff); +            minff= FFMIN(minff, ff); +            maxsf= FFMAX(maxsf, sf); +            minsf= FFMIN(minsf, sf); +            if(i%11==0){ +                av_log(NULL, AV_LOG_ERROR, "i:%4d ss:%f ff:%13.6e-%13.6e sf:%13.6e-%13.6e\n", i, ss, maxff, minff, maxsf, minsf); +                minff=minsf= 2; +                maxff=maxsf= -2; +            } +        } +    } +#endif +} + +/** + * Initializes an audio resampler. + * Note, if either rate is not an integer then simply scale both rates up so they are. + */ +AVResampleContext *av_resample_init(int out_rate, int in_rate, int filter_size, int phase_shift, int linear, double cutoff){ +    AVResampleContext *c= av_mallocz(sizeof(AVResampleContext)); +    double factor= FFMIN(out_rate * cutoff / in_rate, 1.0); +    int phase_count= 1<<phase_shift; + +    c->phase_shift= phase_shift; +    c->phase_mask= phase_count-1; +    c->linear= linear; + +    c->filter_length= FFMAX((int)ceil(filter_size/factor), 1); +    c->filter_bank= av_mallocz(c->filter_length*(phase_count+1)*sizeof(FELEM)); +    av_build_filter(c->filter_bank, factor, c->filter_length, phase_count, 1<<FILTER_SHIFT, WINDOW_TYPE); +    memcpy(&c->filter_bank[c->filter_length*phase_count+1], c->filter_bank, (c->filter_length-1)*sizeof(FELEM)); +    c->filter_bank[c->filter_length*phase_count]= c->filter_bank[c->filter_length - 1]; + +    c->src_incr= out_rate; +    c->ideal_dst_incr= c->dst_incr= in_rate * phase_count; +    c->index= -phase_count*((c->filter_length-1)/2); + +    return c; +} + +void av_resample_close(AVResampleContext *c){ +    av_freep(&c->filter_bank); +    av_freep(&c); +} + +/** + * Compensates samplerate/timestamp drift. The compensation is done by changing + * the resampler parameters, so no audible clicks or similar distortions ocur + * @param compensation_distance distance in output samples over which the compensation should be performed + * @param sample_delta number of output samples which should be output less + * + * example: av_resample_compensate(c, 10, 500) + * here instead of 510 samples only 500 samples would be output + * + * note, due to rounding the actual compensation might be slightly different, + * especially if the compensation_distance is large and the in_rate used during init is small + */ +void av_resample_compensate(AVResampleContext *c, int sample_delta, int compensation_distance){ +//    sample_delta += (c->ideal_dst_incr - c->dst_incr)*(int64_t)c->compensation_distance / c->ideal_dst_incr; +    c->compensation_distance= compensation_distance; +    c->dst_incr = c->ideal_dst_incr - c->ideal_dst_incr * (int64_t)sample_delta / compensation_distance; +} + +/** + * resamples. + * @param src an array of unconsumed samples + * @param consumed the number of samples of src which have been consumed are returned here + * @param src_size the number of unconsumed samples available + * @param dst_size the amount of space in samples available in dst + * @param update_ctx if this is 0 then the context wont be modified, that way several channels can be resampled with the same context + * @return the number of samples written in dst or -1 if an error occured + */ +int av_resample(AVResampleContext *c, short *dst, short *src, int *consumed, int src_size, int dst_size, int update_ctx){ +    int dst_index, i; +    int index= c->index; +    int frac= c->frac; +    int dst_incr_frac= c->dst_incr % c->src_incr; +    int dst_incr=      c->dst_incr / c->src_incr; +    int compensation_distance= c->compensation_distance; + +  if(compensation_distance == 0 && c->filter_length == 1 && c->phase_shift==0){ +        int64_t index2= ((int64_t)index)<<32; +        int64_t incr= (1LL<<32) * c->dst_incr / c->src_incr; +        dst_size= FFMIN(dst_size, (src_size-1-index) * (int64_t)c->src_incr / c->dst_incr); + +        for(dst_index=0; dst_index < dst_size; dst_index++){ +            dst[dst_index] = src[index2>>32]; +            index2 += incr; +        } +        frac += dst_index * dst_incr_frac; +        index += dst_index * dst_incr; +        index += frac / c->src_incr; +        frac %= c->src_incr; +  }else{ +    for(dst_index=0; dst_index < dst_size; dst_index++){ +        FELEM *filter= c->filter_bank + c->filter_length*(index & c->phase_mask); +        int sample_index= index >> c->phase_shift; +        FELEM2 val=0; + +        if(sample_index < 0){ +            for(i=0; i<c->filter_length; i++) +                val += src[FFABS(sample_index + i) % src_size] * filter[i]; +        }else if(sample_index + c->filter_length > src_size){ +            break; +        }else if(c->linear){ +            FELEM2 v2=0; +            for(i=0; i<c->filter_length; i++){ +                val += src[sample_index + i] * (FELEM2)filter[i]; +                v2  += src[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]; +            } +        } + +#ifdef CONFIG_RESAMPLE_AUDIOPHILE_KIDDY_MODE +        dst[dst_index] = av_clip_int16(lrintf(val)); +#else +        val = (val + (1<<(FILTER_SHIFT-1)))>>FILTER_SHIFT; +        dst[dst_index] = (unsigned)(val + 32768) > 65535 ? (val>>31) ^ 32767 : val; +#endif + +        frac += dst_incr_frac; +        index += dst_incr; +        if(frac >= c->src_incr){ +            frac -= c->src_incr; +            index++; +        } + +        if(dst_index + 1 == compensation_distance){ +            compensation_distance= 0; +            dst_incr_frac= c->ideal_dst_incr % c->src_incr; +            dst_incr=      c->ideal_dst_incr / c->src_incr; +        } +    } +  } +    *consumed= FFMAX(index, 0) >> c->phase_shift; +    if(index>=0) index &= c->phase_mask; + +    if(compensation_distance){ +        compensation_distance -= dst_index; +        assert(compensation_distance > 0); +    } +    if(update_ctx){ +        c->frac= frac; +        c->index= index; +        c->dst_incr= dst_incr_frac + c->src_incr*dst_incr; +        c->compensation_distance= compensation_distance; +    } +#if 0 +    if(update_ctx && !c->compensation_distance){ +#undef rand +        av_resample_compensate(c, rand() % (8000*2) - 8000, 8000*2); +av_log(NULL, AV_LOG_DEBUG, "%d %d %d\n", c->dst_incr, c->ideal_dst_incr, c->compensation_distance); +    } +#endif + +    return dst_index; +}  | 
