From: Maxime Even Date: Mon, 8 Jul 2024 17:51:14 +0200 Subject: spectrogram: allows better visualization of low frequencies In some cases, Y which represents the height of a column was equal to 1 and therefore when passed through the log, the output displayed was zero, by adding this 0.1, this allows you to see a column when y = 1 without really changing the height of each column (cherry picked from commit c347fed91e76bd31387171e1ff67224c21194362) --- modules/visualization/glspectrum.c | 7 +++++-- modules/visualization/visual/effects.c | 7 +++++-- 2 files changed, 10 insertions(+), 4 deletions(-) diff --git a/modules/visualization/glspectrum.c b/modules/visualization/glspectrum.c index 96ee3fe..832a52d 100644 --- a/modules/visualization/glspectrum.c +++ b/modules/visualization/glspectrum.c @@ -58,6 +58,8 @@ static void Close(vlc_object_t *); #define HEIGHT_TEXT N_("Video height") #define HEIGHT_LONGTEXT N_("The height of the visualization window, in pixels.") +#define LOG_OFFSET 0.1 + vlc_module_begin() set_shortname(N_("glSpectrum")) set_description(N_("3D OpenGL spectrum visualization")) @@ -466,8 +468,9 @@ static void *Thread( void *p_data ) if (p_dest[j] > y) y = p_dest[j]; } - /* Calculate the height of the bar */ - float new_height = y != 0 ? logf(y) * 0.4f : 0; + /* Calculate the height of the bar + This log_offset makes it possible to display low values */ + float new_height = y != 0 ? logf( y + LOG_OFFSET ) * 0.4f : 0; height[i] = new_height > height[i] ? new_height : height[i]; } diff --git a/modules/visualization/visual/effects.c b/modules/visualization/visual/effects.c index d5a7209..6961c54 100644 --- a/modules/visualization/visual/effects.c +++ b/modules/visualization/visual/effects.c @@ -46,6 +46,8 @@ #define GRAD_ANGLE_MAX 0.5 #define GRAD_INCR 0.01 +#define LOG_OFFSET 0.1 + /***************************************************************************** * dummy_Run *****************************************************************************/ @@ -231,10 +233,11 @@ static int spectrum_Run(visual_effect_t * p_effect, vlc_object_t *p_aout, if ( p_dest[j] > y ) y = p_dest[j]; } - /* Calculate the height of the bar */ + /* Calculate the height of the bar + This log_offset makes it possible to display low values */ if( y != 0 ) { - height[i] = log( y ) * 30; + height[i] = log( y + LOG_OFFSET ) * 30; if( height[i] > 380 ) height[i] = 380; }