Add libswresample.

Similar to libswscale this does resampling and format convertion, just for audio
instead of video.
changing sampling rate, sample formats, channel layouts and sample packing all
in one with a very simple public interface.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

1 files changed, 271 insertions, 0 deletions

diff --git a/libswresample/rematrix.c b/libswresample/rematrix.c
new file mode 100644
index 0000000000..b8c5d45327
--- /dev/null
+++ b/libswresample/rematrix.c
@@ -0,0 +1,271 @@
+/*
+ * Copyright (C) 2011 Michael Niedermayer (michaelni@gmx.at)
+ *
+ * This file is part of libswresample
+ *
+ * libswresample 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.
+ *
+ * libswresample 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 libswresample; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "swresample_internal.h"
+#include "libavutil/audioconvert.h"
+#include "libavutil/avassert.h"
+
+#define SAMPLE float
+#define RENAME(x) x ## _float
+#include "rematrix_template.c"
+#undef SAMPLE
+#undef RENAME
+
+#define SAMPLE int16_t
+#define RENAME(x) x ## _s16
+#include "rematrix_template.c"
+
+
+#define FRONT_LEFT             0
+#define FRONT_RIGHT            1
+#define FRONT_CENTER           2
+#define LOW_FREQUENCY          3
+#define BACK_LEFT              4
+#define BACK_RIGHT             5
+#define FRONT_LEFT_OF_CENTER   6
+#define FRONT_RIGHT_OF_CENTER  7
+#define BACK_CENTER            8
+#define SIDE_LEFT              9
+#define SIDE_RIGHT             10
+#define TOP_CENTER             11
+#define TOP_FRONT_LEFT         12
+#define TOP_FRONT_CENTER       13
+#define TOP_FRONT_RIGHT        14
+#define TOP_BACK_LEFT          15
+#define TOP_BACK_CENTER        16
+#define TOP_BACK_RIGHT         17
+
+static int even(int64_t layout){
+    if(!layout) return 1;
+    if(layout&(layout-1)) return 1;
+    return 0;
+}
+
+static int sane_layout(int64_t layout){
+    if(!(layout & AV_CH_LAYOUT_SURROUND)) // at least 1 front speaker
+        return 0;
+    if(!even(layout & (AV_CH_FRONT_LEFT | AV_CH_FRONT_RIGHT))) // no asymetric front
+        return 0;
+    if(!even(layout & (AV_CH_SIDE_LEFT | AV_CH_SIDE_RIGHT)))   // no asymetric side
+        return 0;
+    if(!even(layout & (AV_CH_BACK_LEFT | AV_CH_BACK_RIGHT)))
+        return 0;
+    if(!even(layout & (AV_CH_FRONT_LEFT_OF_CENTER | AV_CH_FRONT_RIGHT_OF_CENTER)))
+        return 0;
+    if(av_get_channel_layout_nb_channels(layout) >= SWR_CH_MAX)
+        return 0;
+
+    return 1;
+}
+
+int swr_rematrix_init(SwrContext *s){
+    int i, j, in_i, out_i;
+    float matrix[64][64]={0};
+    int64_t unaccounted= s->in_ch_layout & ~s->out_ch_layout;
+    float maxcoef=0;
+
+    for(i=0; i<64; i++){
+        if(s->in_ch_layout & s->out_ch_layout & (1LL<<i))
+            matrix[i][i]= 1.0;
+    }
+
+    if(!sane_layout(s->in_ch_layout)){
+        av_log(s, AV_LOG_ERROR, "Input channel layout isnt supported\n");
+        return AVERROR(EINVAL);
+    }
+    if(!sane_layout(s->out_ch_layout)){
+        av_log(s, AV_LOG_ERROR, "Output channel layout isnt supported\n");
+        return AVERROR(EINVAL);
+    }
+
+//FIXME implement dolby surround
+//FIXME implement full ac3
+
+
+    if(unaccounted & AV_CH_FRONT_CENTER){
+        if((s->out_ch_layout & AV_CH_LAYOUT_STEREO) == AV_CH_LAYOUT_STEREO){
+            matrix[ FRONT_LEFT][FRONT_CENTER]+= sqrt(0.5);
+            matrix[FRONT_RIGHT][FRONT_CENTER]+= sqrt(0.5);
+        }else
+            av_assert0(0);
+    }
+    if(unaccounted & AV_CH_LAYOUT_STEREO){
+        if(s->out_ch_layout & AV_CH_FRONT_CENTER){
+            matrix[FRONT_CENTER][ FRONT_LEFT]+= sqrt(0.5);
+            matrix[FRONT_CENTER][FRONT_RIGHT]+= sqrt(0.5);
+            if(s->in_ch_layout & AV_CH_FRONT_CENTER)
+                matrix[FRONT_CENTER][ FRONT_CENTER] = s->clev*sqrt(2);
+        }else
+            av_assert0(0);
+    }
+
+    if(unaccounted & AV_CH_BACK_CENTER){
+        if(s->out_ch_layout & AV_CH_BACK_LEFT){
+            matrix[ BACK_LEFT][BACK_CENTER]+= sqrt(0.5);
+            matrix[BACK_RIGHT][BACK_CENTER]+= sqrt(0.5);
+        }else if(s->out_ch_layout & AV_CH_SIDE_LEFT){
+            matrix[ SIDE_LEFT][BACK_CENTER]+= sqrt(0.5);
+            matrix[SIDE_RIGHT][BACK_CENTER]+= sqrt(0.5);
+        }else if(s->out_ch_layout & AV_CH_FRONT_LEFT){
+            matrix[ FRONT_LEFT][BACK_CENTER]+= s->slev*sqrt(0.5);
+            matrix[FRONT_RIGHT][BACK_CENTER]+= s->slev*sqrt(0.5);
+        }else if(s->out_ch_layout & AV_CH_FRONT_CENTER){
+            matrix[ FRONT_CENTER][BACK_CENTER]+= s->slev*sqrt(0.5);
+        }else
+            av_assert0(0);
+    }
+    if(unaccounted & AV_CH_BACK_LEFT){
+        if(s->out_ch_layout & AV_CH_BACK_CENTER){
+            matrix[BACK_CENTER][ BACK_LEFT]+= sqrt(0.5);
+            matrix[BACK_CENTER][BACK_RIGHT]+= sqrt(0.5);
+        }else if(s->out_ch_layout & AV_CH_SIDE_LEFT){
+            if(s->in_ch_layout & AV_CH_SIDE_LEFT){
+                matrix[ SIDE_LEFT][ BACK_LEFT]+= sqrt(0.5);
+                matrix[SIDE_RIGHT][BACK_RIGHT]+= sqrt(0.5);
+            }else{
+            matrix[ SIDE_LEFT][ BACK_LEFT]+= 1.0;
+            matrix[SIDE_RIGHT][BACK_RIGHT]+= 1.0;
+            }
+        }else if(s->out_ch_layout & AV_CH_FRONT_LEFT){
+            matrix[ FRONT_LEFT][ BACK_LEFT]+= s->slev;
+            matrix[FRONT_RIGHT][BACK_RIGHT]+= s->slev;
+        }else if(s->out_ch_layout & AV_CH_FRONT_CENTER){
+            matrix[ FRONT_CENTER][BACK_LEFT ]+= s->slev*sqrt(0.5);
+            matrix[ FRONT_CENTER][BACK_RIGHT]+= s->slev*sqrt(0.5);
+        }else
+            av_assert0(0);
+    }
+
+    if(unaccounted & AV_CH_SIDE_LEFT){
+        if(s->out_ch_layout & AV_CH_BACK_LEFT){
+            matrix[ BACK_LEFT][ SIDE_LEFT]+= 1.0;
+            matrix[BACK_RIGHT][SIDE_RIGHT]+= 1.0;
+        }else if(s->out_ch_layout & AV_CH_BACK_CENTER){
+            matrix[BACK_CENTER][ SIDE_LEFT]+= sqrt(0.5);
+            matrix[BACK_CENTER][SIDE_RIGHT]+= sqrt(0.5);
+        }else if(s->out_ch_layout & AV_CH_FRONT_LEFT){
+            matrix[ FRONT_LEFT][ SIDE_LEFT]+= s->slev;
+            matrix[FRONT_RIGHT][SIDE_RIGHT]+= s->slev;
+        }else if(s->out_ch_layout & AV_CH_FRONT_CENTER){
+            matrix[ FRONT_CENTER][SIDE_LEFT ]+= s->slev*sqrt(0.5);
+            matrix[ FRONT_CENTER][SIDE_RIGHT]+= s->slev*sqrt(0.5);
+        }else
+            av_assert0(0);
+    }
+
+    if(unaccounted & AV_CH_FRONT_LEFT_OF_CENTER){
+        if(s->out_ch_layout & AV_CH_FRONT_LEFT){
+            matrix[ FRONT_LEFT][ FRONT_LEFT_OF_CENTER]+= 1.0;
+            matrix[FRONT_RIGHT][FRONT_RIGHT_OF_CENTER]+= 1.0;
+        }else if(s->out_ch_layout & AV_CH_FRONT_CENTER){
+            matrix[ FRONT_CENTER][ FRONT_LEFT_OF_CENTER]+= sqrt(0.5);
+            matrix[ FRONT_CENTER][FRONT_RIGHT_OF_CENTER]+= sqrt(0.5);
+        }else
+            av_assert0(0);
+    }
+
+    //FIXME quantize for integeres
+    for(out_i=i=0; i<64; i++){
+        double sum=0;
+        int in_i=0;
+        int ch_in=0;
+        for(j=0; j<64; j++){
+            s->matrix[out_i][in_i]= matrix[i][j];
+            if(matrix[i][j]){
+                s->matrix_ch[out_i][++ch_in]= in_i;
+                sum += fabs(matrix[i][j]);
+            }
+            if(s->in_ch_layout & (1ULL<<j))
+                in_i++;
+        }
+        s->matrix_ch[out_i][0]= ch_in;
+        maxcoef= FFMAX(maxcoef, sum);
+        if(s->out_ch_layout & (1ULL<<i))
+            out_i++;
+    }
+    if((   s->out_sample_fmt < AV_SAMPLE_FMT_FLT
+        || s->int_sample_fmt < AV_SAMPLE_FMT_FLT) && maxcoef > 1.0){
+        for(i=0; i<SWR_CH_MAX; i++)
+            for(j=0; j<SWR_CH_MAX; j++)
+                s->matrix[i][j] /= maxcoef;
+    }
+        for(i=0; i<av_get_channel_layout_nb_channels(s->out_ch_layout); i++){
+            for(j=0; j<av_get_channel_layout_nb_channels(s->in_ch_layout); j++){
+                av_log(NULL, AV_LOG_ERROR, "%f ", s->matrix[i][j]);
+            }
+            av_log(NULL, AV_LOG_ERROR, "\n");
+        }
+    return 0;
+}
+
+int swr_rematrix(SwrContext *s, AudioData *out, AudioData *in, int len, int mustcopy){
+    int out_i, in_i, i, j;
+
+av_assert0(out->ch_count == av_get_channel_layout_nb_channels(s->out_ch_layout));
+av_assert0(in ->ch_count == av_get_channel_layout_nb_channels(s-> in_ch_layout));
+
+    for(out_i=0; out_i<out->ch_count; out_i++){
+        switch(s->matrix_ch[out_i][0]){
+        case 1:
+            in_i= s->matrix_ch[out_i][1];
+            if(mustcopy || s->matrix[out_i][in_i]!=1.0){
+                if(s->int_sample_fmt == AV_SAMPLE_FMT_FLT){
+                    copy_float(out->ch[out_i], in->ch[in_i], s->matrix[out_i][in_i], len);
+                }else
+                    copy_s16  (out->ch[out_i], in->ch[in_i], s->matrix[out_i][in_i], len);
+            }else{
+                out->ch[out_i]= in->ch[in_i];
+            }
+            break;
+        case 2:
+            if(s->int_sample_fmt == AV_SAMPLE_FMT_FLT){
+                sum2_float(out->ch[out_i], in->ch[ s->matrix_ch[out_i][1] ],           in->ch[ s->matrix_ch[out_i][2] ],
+                                 s->matrix[out_i][ s->matrix_ch[out_i][1] ], s->matrix[out_i][ s->matrix_ch[out_i][2] ],
+                           len);
+            }else{
+                sum2_s16  (out->ch[out_i], in->ch[ s->matrix_ch[out_i][1] ],           in->ch[ s->matrix_ch[out_i][2] ],
+                                 s->matrix[out_i][ s->matrix_ch[out_i][1] ], s->matrix[out_i][ s->matrix_ch[out_i][2] ],
+                           len);
+            }
+            break;
+        default:
+            if(s->int_sample_fmt == AV_SAMPLE_FMT_FLT){
+                for(i=0; i<len; i++){
+                    float v=0;
+                    for(j=0; j<s->matrix_ch[out_i][0]; j++){
+                        in_i= s->matrix_ch[out_i][1+j];
+                        v+= ((float*)in->ch[in_i])[i] * s->matrix[out_i][in_i];
+                    }
+                    ((float*)out->ch[out_i])[i]= v;
+                }
+            }else{
+                for(i=0; i<len; i++){
+                    int v=0;
+                    for(j=0; j<s->matrix_ch[out_i][0]; j++){
+                        in_i= s->matrix_ch[out_i][1+j];
+                        v+= ((int16_t*)in->ch[in_i])[i] * s->matrix[out_i][in_i]; //FIXME use int16 coeffs
+                    }
+                    ((int16_t*)out->ch[out_i])[i]= v;
+                }
+            }
+        }
+    }
+    return 0;
+}