diff --git a/libswresample/dither.c b/libswresample/dither.c index d70505c27e..d0193dda46 100644 --- a/libswresample/dither.c +++ b/libswresample/dither.c @@ -94,6 +94,9 @@ int swri_dither_init(SwrContext *s, enum AVSampleFormat out_fmt, enum AVSampleFo scale *= s->dither.scale; + if (out_fmt == AV_SAMPLE_FMT_S32 && s->dither.output_sample_bits) + scale *= 1<<(32-s->dither.output_sample_bits); + s->dither.ns_pos = 0; s->dither.noise_scale= scale; s->dither.ns_scale = scale; diff --git a/libswresample/swresample.c b/libswresample/swresample.c index f69e36eeaf..f85f88fea5 100644 --- a/libswresample/swresample.c +++ b/libswresample/swresample.c @@ -127,6 +127,7 @@ static const AVOption options[]={ { "kaiser_beta" , "set swr Kaiser Window Beta" , OFFSET(kaiser_beta) , AV_OPT_TYPE_INT , {.i64=9 }, 2 , 16 , PARAM }, +{ "output_sample_bits" , "" , OFFSET(dither.output_sample_bits) , AV_OPT_TYPE_INT , {.i64=0 }, 0 , 64 , 0 }, {0} }; diff --git a/libswresample/swresample_internal.h b/libswresample/swresample_internal.h index 3f8090481b..17b85d5263 100644 --- a/libswresample/swresample_internal.h +++ b/libswresample/swresample_internal.h @@ -63,6 +63,7 @@ struct DitherContext { float ns_errors[SWR_CH_MAX][2*NS_TAPS]; AudioData noise; ///< noise used for dithering AudioData temp; ///< temporary storage when writing into the input buffer isnt possible + int output_sample_bits; ///< the number of used output bits, needed to scale dither correctly }; struct SwrContext {