From 4dc74ae2ea13d2e5a8b481961d507df1ff98df97 Mon Sep 17 00:00:00 2001 From: Robin Gareus Date: Thu, 1 Aug 2013 00:35:24 +0200 Subject: use zeroed scratch buffers for "silent" plugin runs Plugins rewrite the buffer data in-place and some plugins can produce output even when fed with silence. Hence, during a PluginInsert::silence() run a plugin can inject data into the "silent" buffers which causes side-effects. Kudos to Chris 'oofus' Goddard for finding this issue. --- libs/ardour/process_thread.cc | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'libs/ardour/process_thread.cc') diff --git a/libs/ardour/process_thread.cc b/libs/ardour/process_thread.cc index 5d8d6f34fd..d4a3d2f390 100644 --- a/libs/ardour/process_thread.cc +++ b/libs/ardour/process_thread.cc @@ -90,7 +90,7 @@ ProcessThread::get_silent_buffers (ChanCount count) } BufferSet& -ProcessThread::get_scratch_buffers (ChanCount count) +ProcessThread::get_scratch_buffers (ChanCount count, bool silence) { ThreadBuffers* tb = _private_thread_buffers.get(); assert (tb); @@ -105,6 +105,14 @@ ProcessThread::get_scratch_buffers (ChanCount count) sb->set_count (sb->available()); } + if (silence) { + for (DataType::iterator t = DataType::begin(); t != DataType::end(); ++t) { + for (uint32_t i = 0; i < sb->count().get(*t); ++i) { + sb->get(*t, i).clear(); + } + } + } + return *sb; } -- cgit v1.2.3