From f9e0e3dea3068453efc0d9559d1b98d22cd5a7cb Mon Sep 17 00:00:00 2001 From: Robin Haberkorn Date: Fri, 15 Sep 2023 20:36:27 +0300 Subject: fixed SubStream of cached streams * in particular: SndfileStream(...):sub(...) for multi-channel audio files. * The fix is more of a workaround just like the initial skipping of samples by sub() is a workaround. I couldn't yet think of a way how to seek in streams elegantly. --- TODO | 3 --- applause.lua | 15 +++++++++++---- 2 files changed, 11 insertions(+), 7 deletions(-) diff --git a/TODO b/TODO index c157b61..d49a831 100644 --- a/TODO +++ b/TODO @@ -3,9 +3,6 @@ * Stream:foreach() cannot be interrupted Perhaps C core should export an interrupted variable that we can check from Lua. For Stream:play() this is solved differently. -* SndfileStream(...):sub(...) does not work for multi-channel audio files. - The reason is that SubStream ticks in gtick() to seek in the source stream - which cannot work in cached streams (SndfileStream:ctor() caches for multi-channel streams). # Features diff --git a/applause.lua b/applause.lua index 2d86aa6..cac9704 100644 --- a/applause.lua +++ b/applause.lua @@ -1707,12 +1707,19 @@ function SubStream:gtick() -- Perhaps ask stream to skip the first self.i-1 samples -- Either gtick() could take an argument or introduce an -- overwritable gtick_seek(). Problem as always is that - -- this would have to chain to substreams. + -- this would have to chain to substreams and its now always + -- obvious how to pass it on (e.g. to MapStream...). -- Perhaps, it would be wiser to let this be handled by -- an optimizer stage that resolves Stream:sub()-calls. - -- @fixme Actually, this is plain wrong and does not work - -- if self.stream is cached. - for _ = 1, self.i-1 do tick() end + for _ = 1, self.i-1 do + tick() + -- self.stream might be cached (somewhere down the line). + -- Therefore it is essential to clear the cache in order to progress + -- the stream. + -- This however might clear more than necessary, + -- resulting in superfluous recalculations. + table.clear(sampleCache) + end local i = self.i -- cgit v1.2.3