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-rw-r--r--audio/filter/af_surround.c246
1 files changed, 0 insertions, 246 deletions
diff --git a/audio/filter/af_surround.c b/audio/filter/af_surround.c
deleted file mode 100644
index fdbd396337..0000000000
--- a/audio/filter/af_surround.c
+++ /dev/null
@@ -1,246 +0,0 @@
-/*
- * Filter to do simple decoding of matrixed surround sound.
- * This will provide a (basic) surround-sound effect from
- * audio encoded for Dolby Surround, Pro Logic etc.
- *
- * Original author: Steve Davies <steve@daviesfam.org>
- *
- * This file is part of mpv.
- *
- * mpv is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * mpv 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 General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with mpv. If not, see <http://www.gnu.org/licenses/>.
- */
-
-/* The principle: Make rear channels by extracting anti-phase data
- from the front channels, delay by 20ms and feed to rear in anti-phase
-*/
-
-
-/* SPLITREAR: Define to decode two distinct rear channels - this
- doesn't work so well in practice because separation in a passive
- matrix is not high. C (dialogue) to Ls and Rs 14dB or so - so
- dialogue leaks to the rear. Still - give it a try and send
- feedback. Comment this define for old behavior of a single
- surround sent to rear in anti-phase */
-#define SPLITREAR 1
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include "af.h"
-#include "dsp.h"
-
-#define L 32 // Length of fir filter
-#define LD 65536 // Length of delay buffer
-
-// 32 Tap fir filter loop unrolled
-#define FIR(x,w,y) \
- y = ( w[0] *x[0] +w[1] *x[1] +w[2] *x[2] +w[3] *x[3] \
- + w[4] *x[4] +w[5] *x[5] +w[6] *x[6] +w[7] *x[7] \
- + w[8] *x[8] +w[9] *x[9] +w[10]*x[10]+w[11]*x[11] \
- + w[12]*x[12]+w[13]*x[13]+w[14]*x[14]+w[15]*x[15] \
- + w[16]*x[16]+w[17]*x[17]+w[18]*x[18]+w[19]*x[19] \
- + w[20]*x[20]+w[21]*x[21]+w[22]*x[22]+w[23]*x[23] \
- + w[24]*x[24]+w[25]*x[25]+w[26]*x[26]+w[27]*x[27] \
- + w[28]*x[28]+w[29]*x[29]+w[30]*x[30]+w[31]*x[31])
-
-// Add to circular queue macro + update index
-#ifdef SPLITREAR
-#define ADDQUE(qi,rq,lq,r,l)\
- lq[qi]=lq[qi+L]=(l);\
- rq[qi]=rq[qi+L]=(r);\
- qi=(qi-1)&(L-1);
-#else
-#define ADDQUE(qi,lq,l)\
- lq[qi]=lq[qi+L]=(l);\
- qi=(qi-1)&(L-1);
-#endif
-
-// Macro for updating queue index in delay queues
-#define UPDATEQI(qi) qi=(qi+1)&(LD-1)
-
-// instance data
-typedef struct af_surround_s
-{
- float lq[2*L]; // Circular queue for filtering left rear channel
- float rq[2*L]; // Circular queue for filtering right rear channel
- float w[L]; // FIR filter coefficients for surround sound 7kHz low-pass
- float* dr; // Delay queue right rear channel
- float* dl; // Delay queue left rear channel
- float d; // Delay time
- int i; // Position in circular buffer
- int wi; // Write index for delay queue
- int ri; // Read index for delay queue
-}af_surround_t;
-
-// Initialization and runtime control
-static int control(struct af_instance* af, int cmd, void* arg)
-{
- af_surround_t *s = af->priv;
- switch(cmd){
- case AF_CONTROL_REINIT:{
- struct mp_audio *in = arg;
- float fc;
- if (!mp_chmap_is_stereo(&in->channels)) {
- MP_ERR(af, "Only stereo input is supported.\n");
- return AF_DETACH;
- }
-
- mp_audio_set_format(in, AF_FORMAT_FLOAT);
- mp_audio_copy_config(af->data, in);
- mp_audio_set_channels_old(af->data, in->nch * 2);
-
- // Surround filer coefficients
- fc = 2.0 * 7000.0/(float)af->data->rate;
- if (-1 == af_filter_design_fir(L, s->w, &fc, LP|HAMMING, 0)){
- MP_ERR(af, "Unable to design low-pass filter.\n");
- return AF_ERROR;
- }
-
- // Free previous delay queues
- free(s->dl);
- free(s->dr);
- // Allocate new delay queues
- s->dl = calloc(LD,af->data->bps);
- s->dr = calloc(LD,af->data->bps);
- if((NULL == s->dl) || (NULL == s->dr))
- MP_FATAL(af, "Out of memory\n");
-
- // Initialize delay queue index
- if(AF_OK != af_from_ms(1, &s->d, &s->wi, af->data->rate, 0.0, 1000.0))
- return AF_ERROR;
-// printf("%i\n",s->wi);
- s->ri = 0;
-
- return AF_OK;
- }
- }
- return AF_UNKNOWN;
-}
-
-// The beginnings of an active matrix...
-static const float steering_matrix[][12] = {
-// LL RL LR RR LS RS
-// LLs RLs LRs RRs LC RC
- {.707, .0, .0, .707, .5, -.5,
- .5878, -.3928, .3928, -.5878, .5, .5},
-};
-
-// Experimental moving average dominance
-//static int amp_L = 0, amp_R = 0, amp_C = 0, amp_S = 0;
-
-static int filter_frame(struct af_instance *af, struct mp_audio *data)
-{
- if (!data)
- return 0;
- struct mp_audio *outframe =
- mp_audio_pool_get(af->out_pool, &af->fmt_out, data->samples);
- if (!outframe) {
- talloc_free(data);
- return -1;
- }
- mp_audio_copy_attributes(outframe, data);
-
- af_surround_t* s = (af_surround_t*)af->priv;
- const float* m = steering_matrix[0];
- float* in = data->planes[0]; // Input audio data
- float* out = outframe->planes[0]; // Output audio data
- float* end = in + data->samples * data->nch;
- int i = s->i; // Filter queue index
- int ri = s->ri; // Read index for delay queue
- int wi = s->wi; // Write index for delay queue
-
- while(in < end){
- /* Dominance:
- abs(in[0]) abs(in[1]);
- abs(in[0]+in[1]) abs(in[0]-in[1]);
- 10 * log( abs(in[0]) / (abs(in[1])|1) );
- 10 * log( abs(in[0]+in[1]) / (abs(in[0]-in[1])|1) ); */
-
- /* About volume balancing...
- Surround encoding does the following:
- Lt=L+.707*C+.707*S, Rt=R+.707*C-.707*S
- So S should be extracted as:
- (Lt-Rt)
- But we are splitting the S to two output channels, so we
- must take 3dB off as we split it:
- Ls=Rs=.707*(Lt-Rt)
- Trouble is, Lt could be +1, Rt -1, so possibility that S will
- overflow. So to avoid that, we cut L/R by 3dB (*.707), and S by
- 6dB (/2). This keeps the overall balance, but guarantees no
- overflow. */
-
- // Output front left and right
- out[0] = m[0]*in[0] + m[1]*in[1];
- out[1] = m[2]*in[0] + m[3]*in[1];
-
- // Low-pass output @ 7kHz
- FIR((&s->lq[i]), s->w, s->dl[wi]);
-
- // Delay output by d ms
- out[2] = s->dl[ri];
-
-#ifdef SPLITREAR
- // Low-pass output @ 7kHz
- FIR((&s->rq[i]), s->w, s->dr[wi]);
-
- // Delay output by d ms
- out[3] = s->dr[ri];
-#else
- out[3] = -out[2];
-#endif
-
- // Update delay queues indexes
- UPDATEQI(ri);
- UPDATEQI(wi);
-
- // Calculate and save surround in circular queue
-#ifdef SPLITREAR
- ADDQUE(i, s->rq, s->lq, m[6]*in[0]+m[7]*in[1], m[8]*in[0]+m[9]*in[1]);
-#else
- ADDQUE(i, s->lq, m[4]*in[0]+m[5]*in[1]);
-#endif
-
- // Next sample...
- in = &in[data->nch];
- out = &out[af->data->nch];
- }
-
- // Save indexes
- s->i = i; s->ri = ri; s->wi = wi;
-
- talloc_free(data);
- af_add_output_frame(af, outframe);
- return 0;
-}
-
-static int af_open(struct af_instance* af){
- af->control=control;
- af->filter_frame = filter_frame;
- return AF_OK;
-}
-
-#define OPT_BASE_STRUCT af_surround_t
-const struct af_info af_info_surround =
-{
- .info = "Surround decoder filter",
- .name = "surround",
- .flags = AF_FLAGS_NOT_REENTRANT,
- .open = af_open,
- .priv_size = sizeof(af_surround_t),
- .options = (const struct m_option[]) {
- OPT_FLOATRANGE("d", d, 0, 0, 1000, OPTDEF_FLOAT(20.0)),
- {0}
- },
-};
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