swr: add dither support.

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

1 files changed, 5 insertions, 0 deletions

diff --git a/libswresample/swresample_internal.h b/libswresample/swresample_internal.h
index 618afc11ff..ebc275913d 100644
--- a/libswresample/swresample_internal.h
+++ b/libswresample/swresample_internal.h
@@ -49,6 +49,7 @@ struct SwrContext {
     float rematrix_volume;                          ///< rematrixing volume coefficient
     const int *channel_map;                         ///< channel index (or -1 if muted channel) map
     int used_ch_count;                              ///< number of used input channels (mapped channel count if channel_map, otherwise in.ch_count)
+    enum SwrDitherType dither_method;
 
     int int_bps;                                    ///< internal bytes per sample
     int resample_first;                             ///< 1 if resampling must come first, 0 if rematrixing
@@ -61,6 +62,7 @@ struct SwrContext {
     AudioData preout;                               ///< pre-output audio data: used for rematrix/resample
     AudioData out;                                  ///< converted output audio data
     AudioData in_buffer;                            ///< cached audio data (convert and resample purpose)
+    AudioData dither;                               ///< cached audio data (convert and resample purpose)
     int in_buffer_index;                            ///< cached buffer position
     int in_buffer_count;                            ///< cached buffer length
     int resample_in_constraint;                     ///< 1 if the input end was reach before the output end, 0 otherwise
@@ -89,5 +91,8 @@ int swri_resample_double(struct ResampleContext *c,double  *dst, const double  *
 
 int swri_rematrix_init(SwrContext *s);
 int swri_rematrix(SwrContext *s, AudioData *out, AudioData *in, int len, int mustcopy);
+void swri_sum2(enum AVSampleFormat format, void *dst, const void *src0, const void *src1, float coef0, float coef1, int len);
+
+void swri_get_dither(void *dst, int len, unsigned seed, enum AVSampleFormat out_fmt, enum AVSampleFormat in_fmt, enum SwrDitherType type);
 
 #endif