if (method == PA_RESAMPLER_AUTO) {
#ifdef HAVE_SPEEX
- method = PA_RESAMPLER_SPEEX_FLOAT_BASE + 3;
+ method = PA_RESAMPLER_SPEEX_FLOAT_BASE + 1;
#else
if (flags & PA_RESAMPLER_VARIABLE_RATE)
method = PA_RESAMPLER_TRIVIAL;
return m;
if (pa_streq(string, "speex-fixed"))
- return PA_RESAMPLER_SPEEX_FIXED_BASE + 3;
+ return PA_RESAMPLER_SPEEX_FIXED_BASE + 1;
if (pa_streq(string, "speex-float"))
- return PA_RESAMPLER_SPEEX_FLOAT_BASE + 3;
+ return PA_RESAMPLER_SPEEX_FLOAT_BASE + 1;
return PA_RESAMPLER_INVALID;
}
memset(m->map_table_i, 0, sizeof(m->map_table_i));
memset(ic_connected, 0, sizeof(ic_connected));
- remix = (r->flags & (PA_RESAMPLER_NO_REMAP|PA_RESAMPLER_NO_REMIX)) == 0;
+ remix = (r->flags & (PA_RESAMPLER_NO_REMAP | PA_RESAMPLER_NO_REMIX)) == 0;
- for (oc = 0; oc < n_oc; oc++) {
- bool oc_connected = false;
- pa_channel_position_t b = r->o_cm.map[oc];
-
- for (ic = 0; ic < n_ic; ic++) {
- pa_channel_position_t a = r->i_cm.map[ic];
+ if (r->flags & PA_RESAMPLER_NO_REMAP) {
+ pa_assert(!remix);
- if (r->flags & PA_RESAMPLER_NO_REMAP) {
- /* We shall not do any remapping. Hence, just check by index */
+ for (oc = 0; oc < PA_MIN(n_ic, n_oc); oc++)
+ m->map_table_f[oc][oc] = 1.0f;
- if (ic == oc)
- m->map_table_f[oc][ic] = 1.0;
+ } else if (r->flags & PA_RESAMPLER_NO_REMIX) {
+ pa_assert(!remix);
+ for (oc = 0; oc < n_oc; oc++) {
+ pa_channel_position_t b = r->o_cm.map[oc];
- continue;
- }
+ for (ic = 0; ic < n_ic; ic++) {
+ pa_channel_position_t a = r->i_cm.map[ic];
- if (r->flags & PA_RESAMPLER_NO_REMIX) {
/* We shall not do any remixing. Hence, just check by name */
-
if (a == b)
- m->map_table_f[oc][ic] = 1.0;
-
- continue;
+ m->map_table_f[oc][ic] = 1.0f;
}
+ }
+ } else {
- pa_assert(remix);
-
- /* OK, we shall do the full monty: upmixing and
- * downmixing. Our algorithm is relatively simple, does
- * not do spacialization, delay elements or apply lowpass
- * filters for LFE. Patches are always welcome,
- * though. Oh, and it doesn't do any matrix
- * decoding. (Which probably wouldn't make any sense
- * anyway.)
- *
- * This code is not idempotent: downmixing an upmixed
- * stereo stream is not identical to the original. The
- * volume will not match, and the two channels will be a
- * linear combination of both.
- *
- * This is loosely based on random suggestions found on the
- * Internet, such as this:
- * http://www.halfgaar.net/surround-sound-in-linux and the
- * alsa upmix plugin.
- *
- * The algorithm works basically like this:
- *
- * 1) Connect all channels with matching names.
- *
- * 2) Mono Handling:
- * S:Mono: Copy into all D:channels
- * D:Mono: Avg all S:channels
- *
- * 3) Mix D:Left, D:Right:
- * D:Left: If not connected, avg all S:Left
- * D:Right: If not connected, avg all S:Right
- *
- * 4) Mix D:Center
- * If not connected, avg all S:Center
- * If still not connected, avg all S:Left, S:Right
- *
- * 5) Mix D:LFE
- * If not connected, avg all S:*
- *
- * 6) Make sure S:Left/S:Right is used: S:Left/S:Right: If
- * not connected, mix into all D:left and all D:right
- * channels. Gain is 0.1, the current left and right
- * should be multiplied by 0.9.
- *
- * 7) Make sure S:Center, S:LFE is used:
- *
- * S:Center, S:LFE: If not connected, mix into all
- * D:left, all D:right, all D:center channels, gain is
- * 0.375. The current (as result of 1..6) factors
- * should be multiplied by 0.75. (Alt. suggestion: 0.25
- * vs. 0.5) If C-front is only mixed into
- * L-front/R-front if available, otherwise into all L/R
- * channels. Similarly for C-rear.
- *
- * S: and D: shall relate to the source resp. destination channels.
- *
- * Rationale: 1, 2 are probably obvious. For 3: this
- * copies front to rear if needed. For 4: we try to find
- * some suitable C source for C, if we don't find any, we
- * avg L and R. For 5: LFE is mixed from all channels. For
- * 6: the rear channels should not be dropped entirely,
- * however have only minimal impact. For 7: movies usually
- * encode speech on the center channel. Thus we have to
- * make sure this channel is distributed to L and R if not
- * available in the output. Also, LFE is used to achieve a
- * greater dynamic range, and thus we should try to do our
- * best to pass it to L+R.
- */
-
- if (a == b || a == PA_CHANNEL_POSITION_MONO) {
- m->map_table_f[oc][ic] = 1.0;
-
- oc_connected = true;
- ic_connected[ic] = true;
- }
- else if (b == PA_CHANNEL_POSITION_MONO) {
- if (n_ic)
- m->map_table_f[oc][ic] = 1.0f / (float) n_ic;
+ /* OK, we shall do the full monty: upmixing and downmixing. Our
+ * algorithm is relatively simple, does not do spacialization, delay
+ * elements or apply lowpass filters for LFE. Patches are always
+ * welcome, though. Oh, and it doesn't do any matrix decoding. (Which
+ * probably wouldn't make any sense anyway.)
+ *
+ * This code is not idempotent: downmixing an upmixed stereo stream is
+ * not identical to the original. The volume will not match, and the
+ * two channels will be a linear combination of both.
+ *
+ * This is loosely based on random suggestions found on the Internet,
+ * such as this:
+ * http://www.halfgaar.net/surround-sound-in-linux and the alsa upmix
+ * plugin.
+ *
+ * The algorithm works basically like this:
+ *
+ * 1) Connect all channels with matching names.
+ *
+ * 2) Mono Handling:
+ * S:Mono: Copy into all D:channels
+ * D:Mono: Avg all S:channels
+ *
+ * 3) Mix D:Left, D:Right:
+ * D:Left: If not connected, avg all S:Left
+ * D:Right: If not connected, avg all S:Right
+ *
+ * 4) Mix D:Center
+ * If not connected, avg all S:Center
+ * If still not connected, avg all S:Left, S:Right
+ *
+ * 5) Mix D:LFE
+ * If not connected, avg all S:*
+ *
+ * 6) Make sure S:Left/S:Right is used: S:Left/S:Right: If not
+ * connected, mix into all D:left and all D:right channels. Gain is
+ * 1/9.
+ *
+ * 7) Make sure S:Center, S:LFE is used:
+ *
+ * S:Center, S:LFE: If not connected, mix into all D:left, all
+ * D:right, all D:center channels. Gain is 0.5 for center and 0.375
+ * for LFE. C-front is only mixed into L-front/R-front if available,
+ * otherwise into all L/R channels. Similarly for C-rear.
+ *
+ * 8) Normalize each row in the matrix such that the sum for each row is
+ * not larger than 1.0 in order to avoid clipping.
+ *
+ * S: and D: shall relate to the source resp. destination channels.
+ *
+ * Rationale: 1, 2 are probably obvious. For 3: this copies front to
+ * rear if needed. For 4: we try to find some suitable C source for C,
+ * if we don't find any, we avg L and R. For 5: LFE is mixed from all
+ * channels. For 6: the rear channels should not be dropped entirely,
+ * however have only minimal impact. For 7: movies usually encode
+ * speech on the center channel. Thus we have to make sure this channel
+ * is distributed to L and R if not available in the output. Also, LFE
+ * is used to achieve a greater dynamic range, and thus we should try
+ * to do our best to pass it to L+R.
+ */
- oc_connected = true;
- ic_connected[ic] = true;
- }
+ unsigned
+ ic_left = 0,
+ ic_right = 0,
+ ic_center = 0,
+ ic_unconnected_left = 0,
+ ic_unconnected_right = 0,
+ ic_unconnected_center = 0,
+ ic_unconnected_lfe = 0;
+ bool ic_unconnected_center_mixed_in = 0;
+
+ pa_assert(remix);
+
+ for (ic = 0; ic < n_ic; ic++) {
+ if (on_left(r->i_cm.map[ic]))
+ ic_left++;
+ if (on_right(r->i_cm.map[ic]))
+ ic_right++;
+ if (on_center(r->i_cm.map[ic]))
+ ic_center++;
}
- if (!oc_connected && remix) {
- /* OK, we shall remix */
+ for (oc = 0; oc < n_oc; oc++) {
+ bool oc_connected = false;
+ pa_channel_position_t b = r->o_cm.map[oc];
- /* Try to find matching input ports for this output port */
+ for (ic = 0; ic < n_ic; ic++) {
+ pa_channel_position_t a = r->i_cm.map[ic];
- if (on_left(b)) {
- unsigned n = 0;
+ if (a == b || a == PA_CHANNEL_POSITION_MONO) {
+ m->map_table_f[oc][ic] = 1.0f;
- /* We are not connected and on the left side, let's
- * average all left side input channels. */
+ oc_connected = true;
+ ic_connected[ic] = true;
+ }
+ else if (b == PA_CHANNEL_POSITION_MONO) {
+ m->map_table_f[oc][ic] = 1.0f / (float) n_ic;
- for (ic = 0; ic < n_ic; ic++)
- if (on_left(r->i_cm.map[ic]))
- n++;
+ oc_connected = true;
+ ic_connected[ic] = true;
+ }
+ }
- if (n > 0)
- for (ic = 0; ic < n_ic; ic++)
- if (on_left(r->i_cm.map[ic])) {
- m->map_table_f[oc][ic] = 1.0f / (float) n;
- ic_connected[ic] = true;
- }
+ if (!oc_connected) {
+ /* Try to find matching input ports for this output port */
- /* We ignore the case where there is no left input
- * channel. Something is really wrong in this case
- * anyway. */
+ if (on_left(b)) {
- } else if (on_right(b)) {
- unsigned n = 0;
+ /* We are not connected and on the left side, let's
+ * average all left side input channels. */
- /* We are not connected and on the right side, let's
- * average all right side input channels. */
+ if (ic_left > 0)
+ for (ic = 0; ic < n_ic; ic++)
+ if (on_left(r->i_cm.map[ic])) {
+ m->map_table_f[oc][ic] = 1.0f / (float) ic_left;
+ ic_connected[ic] = true;
+ }
- for (ic = 0; ic < n_ic; ic++)
- if (on_right(r->i_cm.map[ic]))
- n++;
+ /* We ignore the case where there is no left input channel.
+ * Something is really wrong in this case anyway. */
- if (n > 0)
- for (ic = 0; ic < n_ic; ic++)
- if (on_right(r->i_cm.map[ic])) {
- m->map_table_f[oc][ic] = 1.0f / (float) n;
- ic_connected[ic] = true;
- }
+ } else if (on_right(b)) {
- /* We ignore the case where there is no right input
- * channel. Something is really wrong in this case
- * anyway. */
+ /* We are not connected and on the right side, let's
+ * average all right side input channels. */
- } else if (on_center(b)) {
- unsigned n = 0;
+ if (ic_right > 0)
+ for (ic = 0; ic < n_ic; ic++)
+ if (on_right(r->i_cm.map[ic])) {
+ m->map_table_f[oc][ic] = 1.0f / (float) ic_right;
+ ic_connected[ic] = true;
+ }
- /* We are not connected and at the center. Let's
- * average all center input channels. */
+ /* We ignore the case where there is no right input
+ * channel. Something is really wrong in this case anyway.
+ * */
- for (ic = 0; ic < n_ic; ic++)
- if (on_center(r->i_cm.map[ic]))
- n++;
+ } else if (on_center(b)) {
- if (n > 0) {
- for (ic = 0; ic < n_ic; ic++)
- if (on_center(r->i_cm.map[ic])) {
- m->map_table_f[oc][ic] = 1.0f / (float) n;
- ic_connected[ic] = true;
- }
- } else {
+ if (ic_center > 0) {
- /* Hmm, no center channel around, let's synthesize
- * it by mixing L and R.*/
+ /* We are not connected and at the center. Let's average
+ * all center input channels. */
- n = 0;
+ for (ic = 0; ic < n_ic; ic++)
+ if (on_center(r->i_cm.map[ic])) {
+ m->map_table_f[oc][ic] = 1.0f / (float) ic_center;
+ ic_connected[ic] = true;
+ }
- for (ic = 0; ic < n_ic; ic++)
- if (on_left(r->i_cm.map[ic]) || on_right(r->i_cm.map[ic]))
- n++;
+ } else if (ic_left + ic_right > 0) {
+
+ /* Hmm, no center channel around, let's synthesize it
+ * by mixing L and R.*/
- if (n > 0)
for (ic = 0; ic < n_ic; ic++)
if (on_left(r->i_cm.map[ic]) || on_right(r->i_cm.map[ic])) {
- m->map_table_f[oc][ic] = 1.0f / (float) n;
+ m->map_table_f[oc][ic] = 1.0f / (float) (ic_left + ic_right);
ic_connected[ic] = true;
}
+ }
- /* We ignore the case where there is not even a
- * left or right input channel. Something is
- * really wrong in this case anyway. */
- }
-
- } else if (on_lfe(b)) {
+ /* We ignore the case where there is not even a left or
+ * right input channel. Something is really wrong in this
+ * case anyway. */
- /* We are not connected and an LFE. Let's average all
- * channels for LFE. */
+ } else if (on_lfe(b) && !(r->flags & PA_RESAMPLER_NO_LFE)) {
- for (ic = 0; ic < n_ic; ic++) {
+ /* We are not connected and an LFE. Let's average all
+ * channels for LFE. */
- if (!(r->flags & PA_RESAMPLER_NO_LFE))
+ for (ic = 0; ic < n_ic; ic++)
m->map_table_f[oc][ic] = 1.0f / (float) n_ic;
- else
- m->map_table_f[oc][ic] = 0;
- /* Please note that a channel connected to LFE
- * doesn't really count as connected. */
+ /* Please note that a channel connected to LFE doesn't
+ * really count as connected. */
}
}
}
- }
-
- if (remix) {
- unsigned
- ic_unconnected_left = 0,
- ic_unconnected_right = 0,
- ic_unconnected_center = 0,
- ic_unconnected_lfe = 0;
for (ic = 0; ic < n_ic; ic++) {
pa_channel_position_t a = r->i_cm.map[ic];
ic_unconnected_lfe++;
}
- if (ic_unconnected_left > 0) {
+ for (ic = 0; ic < n_ic; ic++) {
+ pa_channel_position_t a = r->i_cm.map[ic];
- /* OK, so there are unconnected input channels on the
- * left. Let's multiply all already connected channels on
- * the left side by .9 and add in our averaged unconnected
- * channels multiplied by .1 */
+ if (ic_connected[ic])
+ continue;
for (oc = 0; oc < n_oc; oc++) {
+ pa_channel_position_t b = r->o_cm.map[oc];
- if (!on_left(r->o_cm.map[oc]))
- continue;
+ if (on_left(a) && on_left(b))
+ m->map_table_f[oc][ic] = (1.f/9.f) / (float) ic_unconnected_left;
- for (ic = 0; ic < n_ic; ic++) {
+ else if (on_right(a) && on_right(b))
+ m->map_table_f[oc][ic] = (1.f/9.f) / (float) ic_unconnected_right;
- if (ic_connected[ic]) {
- m->map_table_f[oc][ic] *= .9f;
- continue;
- }
+ else if (on_center(a) && on_center(b)) {
+ m->map_table_f[oc][ic] = (1.f/9.f) / (float) ic_unconnected_center;
+ ic_unconnected_center_mixed_in = true;
- if (on_left(r->i_cm.map[ic]))
- m->map_table_f[oc][ic] = .1f / (float) ic_unconnected_left;
- }
+ } else if (on_lfe(a) && !(r->flags & PA_RESAMPLER_NO_LFE))
+ m->map_table_f[oc][ic] = .375f / (float) ic_unconnected_lfe;
}
}
- if (ic_unconnected_right > 0) {
+ if (ic_unconnected_center > 0 && !ic_unconnected_center_mixed_in) {
+ unsigned ncenter[PA_CHANNELS_MAX];
+ bool found_frs[PA_CHANNELS_MAX];
- /* OK, so there are unconnected input channels on the
- * right. Let's multiply all already connected channels on
- * the right side by .9 and add in our averaged unconnected
- * channels multiplied by .1 */
+ memset(ncenter, 0, sizeof(ncenter));
+ memset(found_frs, 0, sizeof(found_frs));
- for (oc = 0; oc < n_oc; oc++) {
+ /* Hmm, as it appears there was no center channel we
+ could mix our center channel in. In this case, mix it into
+ left and right. Using .5 as the factor. */
+
+ for (ic = 0; ic < n_ic; ic++) {
- if (!on_right(r->o_cm.map[oc]))
+ if (ic_connected[ic])
continue;
- for (ic = 0; ic < n_ic; ic++) {
+ if (!on_center(r->i_cm.map[ic]))
+ continue;
+
+ for (oc = 0; oc < n_oc; oc++) {
- if (ic_connected[ic]) {
- m->map_table_f[oc][ic] *= .9f;
+ if (!on_left(r->o_cm.map[oc]) && !on_right(r->o_cm.map[oc]))
continue;
- }
- if (on_right(r->i_cm.map[ic]))
- m->map_table_f[oc][ic] = .1f / (float) ic_unconnected_right;
+ if (front_rear_side(r->i_cm.map[ic]) == front_rear_side(r->o_cm.map[oc])) {
+ found_frs[ic] = true;
+ break;
+ }
}
- }
- }
-
- if (ic_unconnected_center > 0) {
- bool mixed_in = false;
-
- /* OK, so there are unconnected input channels on the
- * center. Let's multiply all already connected channels on
- * the center side by .9 and add in our averaged unconnected
- * channels multiplied by .1 */
- for (oc = 0; oc < n_oc; oc++) {
-
- if (!on_center(r->o_cm.map[oc]))
- continue;
-
- for (ic = 0; ic < n_ic; ic++) {
+ for (oc = 0; oc < n_oc; oc++) {
- if (ic_connected[ic]) {
- m->map_table_f[oc][ic] *= .9f;
+ if (!on_left(r->o_cm.map[oc]) && !on_right(r->o_cm.map[oc]))
continue;
- }
- if (on_center(r->i_cm.map[ic])) {
- m->map_table_f[oc][ic] = .1f / (float) ic_unconnected_center;
- mixed_in = true;
- }
+ if (!found_frs[ic] || front_rear_side(r->i_cm.map[ic]) == front_rear_side(r->o_cm.map[oc]))
+ ncenter[oc]++;
}
}
- if (!mixed_in) {
- unsigned ncenter[PA_CHANNELS_MAX];
- bool found_frs[PA_CHANNELS_MAX];
+ for (oc = 0; oc < n_oc; oc++) {
- memset(ncenter, 0, sizeof(ncenter));
- memset(found_frs, 0, sizeof(found_frs));
+ if (!on_left(r->o_cm.map[oc]) && !on_right(r->o_cm.map[oc]))
+ continue;
- /* Hmm, as it appears there was no center channel we
- could mix our center channel in. In this case, mix
- it into left and right. Using .375 and 0.75 as
- factors. */
+ if (ncenter[oc] <= 0)
+ continue;
for (ic = 0; ic < n_ic; ic++) {
- if (ic_connected[ic])
- continue;
-
if (!on_center(r->i_cm.map[ic]))
continue;
- for (oc = 0; oc < n_oc; oc++) {
-
- if (!on_left(r->o_cm.map[oc]) && !on_right(r->o_cm.map[oc]))
- continue;
-
- if (front_rear_side(r->i_cm.map[ic]) == front_rear_side(r->o_cm.map[oc])) {
- found_frs[ic] = true;
- break;
- }
- }
-
- for (oc = 0; oc < n_oc; oc++) {
-
- if (!on_left(r->o_cm.map[oc]) && !on_right(r->o_cm.map[oc]))
- continue;
-
- if (!found_frs[ic] || front_rear_side(r->i_cm.map[ic]) == front_rear_side(r->o_cm.map[oc]))
- ncenter[oc]++;
- }
- }
-
- for (oc = 0; oc < n_oc; oc++) {
-
- if (!on_left(r->o_cm.map[oc]) && !on_right(r->o_cm.map[oc]))
- continue;
-
- if (ncenter[oc] <= 0)
- continue;
-
- for (ic = 0; ic < n_ic; ic++) {
-
- if (ic_connected[ic]) {
- m->map_table_f[oc][ic] *= .75f;
- continue;
- }
-
- if (!on_center(r->i_cm.map[ic]))
- continue;
-
- if (!found_frs[ic] || front_rear_side(r->i_cm.map[ic]) == front_rear_side(r->o_cm.map[oc]))
- m->map_table_f[oc][ic] = .375f / (float) ncenter[oc];
- }
+ if (!found_frs[ic] || front_rear_side(r->i_cm.map[ic]) == front_rear_side(r->o_cm.map[oc]))
+ m->map_table_f[oc][ic] = .5f / (float) ncenter[oc];
}
}
}
+ }
- if (ic_unconnected_lfe > 0 && !(r->flags & PA_RESAMPLER_NO_LFE)) {
-
- /* OK, so there is an unconnected LFE channel. Let's mix
- * it into all channels, with factor 0.375 */
-
- for (ic = 0; ic < n_ic; ic++) {
-
- if (!on_lfe(r->i_cm.map[ic]))
- continue;
+ for (oc = 0; oc < n_oc; oc++) {
+ float sum = 0.0f;
+ for (ic = 0; ic < n_ic; ic++)
+ sum += m->map_table_f[oc][ic];
- for (oc = 0; oc < n_oc; oc++)
- m->map_table_f[oc][ic] = 0.375f / (float) ic_unconnected_lfe;
- }
- }
+ if (sum > 1.0f)
+ for (ic = 0; ic < n_ic; ic++)
+ m->map_table_f[oc][ic] /= sum;
}
+
/* make an 16:16 int version of the matrix */
for (oc = 0; oc < n_oc; oc++)
for (ic = 0; ic < n_ic; ic++)