Several virtual sources and sinks apart from module-echo-cancel also query the master
sink or source to estimate the current latency. Those modules might potentially show
the bug that is described for module-echo-cancel in bug 100277.
This patch checks in the message handlers for the PA_{SINK,SOURCE}_MESSAGE_GET_LATENCY
if the master sink or source is valid and returns 0 as latency if not. This is however
not yet sufficient to solve the issue. Additional patches will follow.
The reported latency of source or sink is based on measured initial conditions.
If the conditions contain an error, the estimated latency values may become negative.
This does not indicate that the latency is indeed negative but can be considered
merely an offset error. The current get_latency_in_thread() calls and the
implementations of the PA_{SINK,SOURCE}_MESSAGE_GET_LATENCY messages truncate negative
latencies because they do not make sense from a physical point of view. In fact,
the values are truncated twice, once in the message handler and a second time in
the pa_{source,sink}_get_latency_within_thread() call itself.
This leads to two problems for the latency controller within module-loopback:
- Truncating leads to discontinuities in the latency reports which then trigger
unwanted end to end latency corrections.
- If a large negative port latency offsets is set, the reported latency is always 0,
making it impossible to control the end to end latency at all.
This patch is a pre-condition for solving these problems.
It adds a new flag to pa_{sink,source}_get_latency_within_thread() to allow
negative return values. Truncating is also removed in all implementations of the
PA_{SINK,SOURCE}_MESSAGE_GET_LATENCY message handlers. The allow_negative flag
is set to false for all calls of pa_{sink,source}_get_latency_within_thread()
except when used within PA_{SINK,SOURCE}_MESSAGE_GET_LATENCY. This means that the
original behavior is not altered in most cases. Only if a positive latency offset
is set and the message returns a negative value, the reported latency is smaller
because the values are not truncated twice.
Additionally let PA_SOURCE_MESSAGE_GET_LATENCY return -pa_sink_get_latency_within_thread()
for monitor sources because the source gets the data before it is played.
The old code worked incorrectly in several situations. For example,
trying to use the "master" argument wouldn't work, because if
"sink_master" wasn't specified, pa_namereg_get() would pick the default
sink as the master sink.
Currently, module-filter-apply cannot load module-virtual-surround-sink because filter-apply
provides the argument "sink_master" but virtual-surround-sink expects "master" instead.
Therefore this patch adds the sink_master argument to module-virtual-surround-sink.
Additionally, the autoloaded argument was also added.
If pa_sink_input_cork() or pa_source_output_cork() were called without a sink
or source attached, the calls would crash pulseaudio.
This patch fixes the problem, so that a source output or sink input can still
be corked or uncorked while source or sink are invalid. This is needed to
correct the corking logic in module-loopback.
Add a user defined parameter lfe-crossover-freq for the lfe-filter,
to pass this parameter to the lfe-filter, we need to change the
pa_resampler_new() API as well.
Signed-off-by: Hui Wang <hui.wang@canonical.com>
FSF addresses used in PA sources are no longer valid and rpmlint
generates numerous warnings during packaging because of this.
This patch changes all FSF addresses to FSF web page according to
the GPL how-to: https://www.gnu.org/licenses/gpl-howto.en.html
Done automatically by sed-ing through sources.
This patch also adds a description how the heuristic works and mentions that
there is a scaling factor that can be adjusted if there is audible clipping.
Since commit e32a408b3c, we silence the
input memblock in order to give the resampler enough input samples, if
necessary.
But if there is no need to resample the hrir, the resampled memblock is
actually the same as the input memblock. Thus, we have to make sure that
we do not silence it in this case.
The sink has different frame size than the sink input, so
the max_request and max_rewind values of the sink input need
to be converted when setting the sink max_request and
max_rewind values.
The conversion is already done correctly in
sink_input_update_max_request_cb() and
sink_input_update_max_rewind_cb().
It provides a virtual surround sound effect.
v2: Normalize hrir to avoid clipping, some cleanups
v3: use fabs, not abs
v4: implement changes proposed by Tanu Kaskinen
v5: likewise
v6: use channel map from hrir file
v7: remove hrir_ss and hrir_map form userdata
v8: update naming of sink
