From afc96087f8a6282cf732d142a4db7a3d604d39d8 Mon Sep 17 00:00:00 2001 From: Bertrik Sikken Date: Tue, 1 May 2012 03:58:27 -0400 Subject: New crossfeed algorithm for Rockbox: "Meier" crossfeed Emulates the basic "Meier" crossfeed (2 capacitors, 3 resistors) as discussed in http://www.meier-audio.homepage.t-online.de/passivefilter.htm This crossfeed blends a bit of low-pass filtered L signal into the R signal (and vice versa) while adding about 300 us delay to the crossfed-signal. A difference with the crossfeed already present in rockbox, is that this algorithm keeps the total spectrum flat (the one currently in rockbox accentuates low-frequency signals, making it sound a bit muffled). This implementation is quite lightweight, just 3 multiplies per left-right pair of samples. Has a default C implementation and optimized assembly versions for ARM and Coldfire. The crossfeed effect is quite subtle and is noticeable mostly one albums that have very strong left-right separation (e.g. one instrument only on the left, another only on the right). In the user interface, the new crossfeed option appears as "Meier" and is not configureable. The existing crossfeed is renamed to "Custom" as it allows itself to be customised. There is no entry for the user manual yet. Change-Id: Iaa100616fe0fcd7e16f08cdb9a7f41501973eee1 --- apps/plugins/mpegplayer/mpeg_settings.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'apps/plugins/mpegplayer') diff --git a/apps/plugins/mpegplayer/mpeg_settings.c b/apps/plugins/mpegplayer/mpeg_settings.c index 7f92fb7c69..bcef4c66bf 100644 --- a/apps/plugins/mpegplayer/mpeg_settings.c +++ b/apps/plugins/mpegplayer/mpeg_settings.c @@ -457,8 +457,9 @@ static void sync_audio_setting(int setting, bool global) break; case MPEG_AUDIO_CROSSFEED: - rb->dsp_crossfeed_enable((global || settings.crossfeed) ? - rb->global_settings->crossfeed : false); + rb->dsp_set_crossfeed_type((global || settings.crossfeed) ? + rb->global_settings->crossfeed : + CROSSFEED_TYPE_NONE); break; case MPEG_AUDIO_EQUALIZER: -- cgit v1.2.3