calc_map_table(r);
- pa_log_info("Using resampler '%s'", pa_resample_method_to_string(method));
-
r->work_format = pa_resampler_choose_work_format(method, a->format, b->format, r->map_required);
-
- pa_log_info("Using %s as working format.", pa_sample_format_to_string(r->work_format));
-
r->w_sz = pa_sample_size_of_format(r->work_format);
if (r->i_ss.format != r->work_format) {
}
}
- /* leftover buffer is the buffer before the resampling stage */
- r->leftover_buf = &r->remap_buf;
- r->leftover_buf_size = &r->remap_buf_size;
- r->have_leftover = &r->leftover_in_remap;
+ if (r->o_ss.channels <= r->i_ss.channels) {
+ /* pipeline is: format conv. -> remap -> resample -> format conv. */
+ r->work_channels = r->o_ss.channels;
+
+ /* leftover buffer is remap output buffer (before resampling) */
+ r->leftover_buf = &r->remap_buf;
+ r->leftover_buf_size = &r->remap_buf_size;
+ r->have_leftover = &r->leftover_in_remap;
+ } else {
+ /* pipeline is: format conv. -> resample -> remap -> format conv. */
+ r->work_channels = r->i_ss.channels;
- r->work_channels = r->o_ss.channels;
+ /* leftover buffer is to_work output buffer (before resampling) */
+ r->leftover_buf = &r->to_work_format_buf;
+ r->leftover_buf_size = &r->to_work_format_buf_size;
+ r->have_leftover = &r->leftover_in_to_work;
+ }
r->w_fz = pa_sample_size_of_format(r->work_format) * r->work_channels;
+ pa_log_debug("Resampler:");
+ pa_log_debug(" rate %d -> %d (method %s)", a->rate, b->rate, pa_resample_method_to_string(r->method));
+ pa_log_debug(" format %s -> %s (intermediate %s)", pa_sample_format_to_string(a->format),
+ pa_sample_format_to_string(b->format), pa_sample_format_to_string(r->work_format));
+ pa_log_debug(" channels %d -> %d (resampling %d)", a->channels, b->channels, r->work_channels);
+
/* initialize implementation */
if (init_table[method](r) < 0)
goto fail;
buf = (pa_memchunk*) in;
buf = convert_to_work_format(r, buf);
- buf = remap_channels(r, buf);
- buf = resample(r, buf);
+
+ /* Try to save resampling effort: if we have more output channels than
+ * input channels, do resampling first, then remapping. */
+ if (r->o_ss.channels <= r->i_ss.channels) {
+ buf = remap_channels(r, buf);
+ buf = resample(r, buf);
+ } else {
+ buf = resample(r, buf);
+ buf = remap_channels(r, buf);
+ }
if (buf->length) {
buf = convert_from_work_format(r, buf);