swresample/rematrix: add S32 mixing code

Needed for dithering S32
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libswresample/rematrix.c

@@ -34,6 +34,10 @@
 #include "rematrix_template.c"
 #undef TEMPLATE_REMATRIX_S16
 
+#define TEMPLATE_REMATRIX_S32
+#include "rematrix_template.c"
+#undef TEMPLATE_REMATRIX_S32
+
 #define FRONT_LEFT             0
 #define FRONT_RIGHT            1
 #define FRONT_CENTER           2
@@ -366,6 +370,17 @@ av_cold int swri_rematrix_init(SwrContext *s){
         s->mix_1_1_f = (mix_1_1_func_type*)copy_double;
         s->mix_2_1_f = (mix_2_1_func_type*)sum2_double;
         s->mix_any_f = (mix_any_func_type*)get_mix_any_func_double(s);
+    }else if(s->midbuf.fmt == AV_SAMPLE_FMT_S32P){
+        // Only for dithering currently
+//         s->native_matrix = av_calloc(nb_in * nb_out, sizeof(double));
+        s->native_one    = av_mallocz(sizeof(int));
+//         for (i = 0; i < nb_out; i++)
+//             for (j = 0; j < nb_in; j++)
+//                 ((double*)s->native_matrix)[i * nb_in + j] = s->matrix[i][j];
+        *((int*)s->native_one) = 32768;
+        s->mix_1_1_f = (mix_1_1_func_type*)copy_s32;
+        s->mix_2_1_f = (mix_2_1_func_type*)sum2_s32;
+        s->mix_any_f = (mix_any_func_type*)get_mix_any_func_s32(s);
     }else
         av_assert0(0);
     //FIXME quantize for integeres

libswresample/rematrix_template.c

@@ -36,6 +36,12 @@
 #    define COEFF int
 #    define INTER int
 #    define RENAME(x) x ## _s16
+#elif defined(TEMPLATE_REMATRIX_S32)
+#    define R(x) (((x) + 16384)>>15)
+#    define SAMPLE int32_t
+#    define COEFF int
+#    define INTER int64_t
+#    define RENAME(x) x ## _s32
 #endif
 
 typedef void (RENAME(mix_any_func_type))(SAMPLE **out, const SAMPLE **in1, COEFF *coeffp, integer len);