diff --git a/doc/filters.texi b/doc/filters.texi index 04b2d2207f..71f14567a1 100644 --- a/doc/filters.texi +++ b/doc/filters.texi @@ -12685,6 +12685,15 @@ stream for better peak accuracy. It logs a message for true-peak. This mode requires a build with @code{libswresample}. @end table +@item dualmono +Treat mono input files as "dual mono". If a mono file is intended for playback +on a stereo system, its EBU R128 measurement will be perceptually incorrect. +If set to @code{true}, this option will compensate for this effect. +Multi-channel input files are not effected by this option. + +@item panlaw +Set a specific pan law to be used for the measurement of dual mono files. +This parameter is optional, and has a default value of -3.01dB. @end table @subsection Examples diff --git a/libavfilter/f_ebur128.c b/libavfilter/f_ebur128.c index 1d5c8fd0f1..c63356fbca 100644 --- a/libavfilter/f_ebur128.c +++ b/libavfilter/f_ebur128.c @@ -139,6 +139,8 @@ typedef struct { /* misc */ int loglevel; ///< log level for frame logging int metadata; ///< whether or not to inject loudness results in frames + int dual_mono; ///< whether or not to treat single channel input files as dual-mono + double pan_law; ///< pan law value used to calulate dual-mono measurements } EBUR128Context; enum { @@ -163,6 +165,8 @@ static const AVOption ebur128_options[] = { { "none", "disable any peak mode", 0, AV_OPT_TYPE_CONST, {.i64 = PEAK_MODE_NONE}, INT_MIN, INT_MAX, A|F, "mode" }, { "sample", "enable peak-sample mode", 0, AV_OPT_TYPE_CONST, {.i64 = PEAK_MODE_SAMPLES_PEAKS}, INT_MIN, INT_MAX, A|F, "mode" }, { "true", "enable true-peak mode", 0, AV_OPT_TYPE_CONST, {.i64 = PEAK_MODE_TRUE_PEAKS}, INT_MIN, INT_MAX, A|F, "mode" }, + { "dualmono", "treat mono input files as dual-mono", OFFSET(dual_mono), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, A|F }, + { "panlaw", "set a specific pan law for dual-mono files", OFFSET(pan_law), AV_OPT_TYPE_DOUBLE, {.dbl = -3.01029995663978}, -10.0, 0.0, A|F }, { NULL }, }; @@ -661,6 +665,10 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *insamples) } if (nb_integrated) ebur128->integrated_loudness = LOUDNESS(integrated_sum / nb_integrated); + /* dual-mono correction */ + if (nb_channels == 1 && ebur128->dual_mono) { + ebur128->integrated_loudness -= ebur128->pan_law; + } } /* LRA */ @@ -707,6 +715,12 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *insamples) } } + /* dual-mono correction */ + if (nb_channels == 1 && ebur128->dual_mono) { + loudness_400 -= ebur128->pan_law; + loudness_3000 -= ebur128->pan_law; + } + #define LOG_FMT "M:%6.1f S:%6.1f I:%6.1f LUFS LRA:%6.1f LU" /* push one video frame */ @@ -855,6 +869,14 @@ static av_cold void uninit(AVFilterContext *ctx) int i; EBUR128Context *ebur128 = ctx->priv; + /* dual-mono correction */ + if (ebur128->nb_channels == 1 && ebur128->dual_mono) { + ebur128->i400.rel_threshold -= ebur128->pan_law; + ebur128->i3000.rel_threshold -= ebur128->pan_law; + ebur128->lra_low -= ebur128->pan_law; + ebur128->lra_high -= ebur128->pan_law; + } + av_log(ctx, AV_LOG_INFO, "Summary:\n\n" " Integrated loudness:\n" " I: %5.1f LUFS\n"