[FFmpeg-cvslog] dca: support mixing LFE in dca_downmix.
Tim Walker
git at videolan.org
Fri Nov 29 04:21:57 CET 2013
ffmpeg | branch: master | Tim Walker <tdskywalker at gmail.com> | Fri Nov 22 23:47:03 2013 +0100| [aaa44d0299338e3bc90128816c21dbfab06cdb48] | committer: Anton Khirnov
dca: support mixing LFE in dca_downmix.
Embedded downmix coefficients can use this.
Signed-off-by: Anton Khirnov <anton at khirnov.net>
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=aaa44d0299338e3bc90128816c21dbfab06cdb48
---
libavcodec/dcadata.h | 22 +++++++++++-----------
libavcodec/dcadec.c | 43 ++++++++++++++++++++++++++-----------------
2 files changed, 37 insertions(+), 28 deletions(-)
diff --git a/libavcodec/dcadata.h b/libavcodec/dcadata.h
index e6997bc..dc4e8b9 100644
--- a/libavcodec/dcadata.h
+++ b/libavcodec/dcadata.h
@@ -7551,17 +7551,17 @@ static const float dca_dmixtable[241] = {
1.000000,
};
-static const float dca_default_coeffs[10][5][2] = {
- { { 0.707107, 0.707107 }, }, // A
- { { 1.000000, 0.000000 }, { 0.000000, 1.000000 }, }, // A + B (dual mono)
- { { 1.000000, 0.000000 }, { 0.000000, 1.000000 }, }, // L + R (stereo)
- { { 1.000000, 0.000000 }, { 0.000000, 1.000000 }, }, // (L+R) + (L-R) (sum-difference)
- { { 1.000000, 0.000000 }, { 0.000000, 1.000000 }, }, // LT + RT (left and right total)
- { { 0.501187, 0.501187 }, { 0.707107, 0.000000 }, { 0.000000, 0.707107 }, }, // C + L + R
- { { 0.707107, 0.000000 }, { 0.000000, 0.707107 }, { 0.501187, 0.501187 }, }, // L + R + S
- { { 0.501187, 0.501187 }, { 0.707107, 0.000000 }, { 0.000000, 0.707107 }, { 0.501187, 0.501187 }, }, // C + L + R + S
- { { 0.707107, 0.000000 }, { 0.000000, 0.707107 }, { 0.501187, 0.000000 }, { 0.000000, 0.501187 }, }, // L + R + SL + SR
- { { 0.501187, 0.501187 }, { 0.707107, 0.000000 }, { 0.000000, 0.707107 }, { 0.501187, 0.000000 }, { 0.000000, 0.501187 }, }, // C + L + R + SL + SR
+static const float dca_default_coeffs[10][6][2] = {
+ { { 0.707107, 0.707107 }, { 0.000000, 0.000000 }, }, // A [LFE]
+ { { 1.000000, 0.000000 }, { 0.000000, 1.000000 }, { 0.000000, 0.000000 }, }, // A + B (dual mono) [LFE]
+ { { 1.000000, 0.000000 }, { 0.000000, 1.000000 }, { 0.000000, 0.000000 }, }, // L + R (stereo) [LFE]
+ { { 1.000000, 0.000000 }, { 0.000000, 1.000000 }, { 0.000000, 0.000000 }, }, // (L+R) + (L-R) (sum-difference) [LFE]
+ { { 1.000000, 0.000000 }, { 0.000000, 1.000000 }, { 0.000000, 0.000000 }, }, // LT + RT (left and right total) [LFE]
+ { { 0.501187, 0.501187 }, { 0.707107, 0.000000 }, { 0.000000, 0.707107 }, { 0.000000, 0.000000 }, }, // C + L + R [LFE]
+ { { 0.707107, 0.000000 }, { 0.000000, 0.707107 }, { 0.501187, 0.501187 }, { 0.000000, 0.000000 }, }, // L + R + S [LFE]
+ { { 0.501187, 0.501187 }, { 0.707107, 0.000000 }, { 0.000000, 0.707107 }, { 0.501187, 0.501187 }, { 0.000000, 0.000000 }, }, // C + L + R + S [LFE]
+ { { 0.707107, 0.000000 }, { 0.000000, 0.707107 }, { 0.501187, 0.000000 }, { 0.000000, 0.501187 }, { 0.000000, 0.000000 }, }, // L + R + SL + SR [LFE]
+ { { 0.501187, 0.501187 }, { 0.707107, 0.000000 }, { 0.000000, 0.707107 }, { 0.501187, 0.000000 }, { 0.000000, 0.501187 }, { 0.000000, 0.000000 }, }, // C + L + R + SL + SR [LFE]
};
/* downmix coeffs
diff --git a/libavcodec/dcadec.c b/libavcodec/dcadec.c
index cf1da8c..cd4f188 100644
--- a/libavcodec/dcadec.c
+++ b/libavcodec/dcadec.c
@@ -336,7 +336,7 @@ typedef struct {
int scale_factor[DCA_PRIM_CHANNELS_MAX][DCA_SUBBANDS][2]; ///< scale factors (2 if transient)
int joint_huff[DCA_PRIM_CHANNELS_MAX]; ///< joint subband scale factors codebook
int joint_scale_factor[DCA_PRIM_CHANNELS_MAX][DCA_SUBBANDS]; ///< joint subband scale factors
- float downmix_coef[DCA_PRIM_CHANNELS_MAX][2]; ///< stereo downmix coefficients
+ float downmix_coef[DCA_PRIM_CHANNELS_MAX + 1][2]; ///< stereo downmix coefficients
int dynrange_coef; ///< dynamic range coefficient
/* Core substream's embedded downmix coefficients (cf. ETSI TS 102 114 V1.4.1)
@@ -991,8 +991,8 @@ static void lfe_interpolation_fir(DCAContext *s, int decimation_select,
op2 \
}
-static void dca_downmix(float **samples, int srcfmt,
- float coef[DCA_PRIM_CHANNELS_MAX][2],
+static void dca_downmix(float **samples, int srcfmt, int lfe_present,
+ float coef[DCA_PRIM_CHANNELS_MAX + 1][2],
const int8_t *channel_mapping)
{
int c, l, r, sl, sr, s;
@@ -1042,6 +1042,14 @@ static void dca_downmix(float **samples, int srcfmt,
MIX_REAR2(samples, sl, sr, 3, coef));
break;
}
+ if (lfe_present) {
+ int lf_buf = dca_lfe_index[srcfmt];
+ int lf_idx = dca_channels [srcfmt];
+ for (i = 0; i < 256; i++) {
+ samples[0][i] += samples[lf_buf][i] * coef[lf_idx][0];
+ samples[1][i] += samples[lf_buf][i] * coef[lf_idx][1];
+ }
+ }
}
@@ -1249,12 +1257,6 @@ static int dca_filter_channels(DCAContext *s, int block_index)
M_SQRT1_2 / 32768.0 /* pcm_to_double[s->source_pcm_res] */);
}
- /* Down mixing */
- if (s->prim_channels > 2 &&
- s->avctx->request_channel_layout == AV_CH_LAYOUT_STEREO) {
- dca_downmix(s->samples_chanptr, s->amode, s->downmix_coef, s->channel_order_tab);
- }
-
/* Generate LFE samples for this subsubframe FIXME!!! */
if (s->output & DCA_LFE) {
lfe_interpolation_fir(s, s->lfe, 2 * s->lfe,
@@ -1264,6 +1266,13 @@ static int dca_filter_channels(DCAContext *s, int block_index)
/* Outputs 20bits pcm samples */
}
+ /* Downmixing to Stereo */
+ if (s->prim_channels + !!s->lfe > 2 &&
+ s->avctx->request_channel_layout == AV_CH_LAYOUT_STEREO) {
+ dca_downmix(s->samples_chanptr, s->amode, !!s->lfe, s->downmix_coef,
+ s->channel_order_tab);
+ }
+
return 0;
}
@@ -1858,7 +1867,7 @@ FF_ENABLE_DEPRECATION_WARNINGS
s->channel_order_tab[channels - 1 - !!s->lfe] < 0)
return AVERROR_INVALIDDATA;
- if (s->prim_channels > 2 &&
+ if (s->prim_channels + !!s->lfe > 2 &&
avctx->request_channel_layout == AV_CH_LAYOUT_STEREO) {
channels = 2;
s->output = DCA_STEREO;
@@ -1868,12 +1877,11 @@ FF_ENABLE_DEPRECATION_WARNINGS
*
* The decoder can only downmix to 2-channel, so we need to ensure
* embedded downmix coefficients are actually targeting 2-channel.
- *
- * Coefficients for the LFE channel are ignored (not supported) */
+ */
if (s->core_downmix && (s->core_downmix_amode == DCA_STEREO ||
s->core_downmix_amode == DCA_STEREO_TOTAL)) {
int sign, code;
- for (i = 0; i < s->prim_channels; i++) {
+ for (i = 0; i < s->prim_channels + !!s->lfe; i++) {
sign = s->core_downmix_codes[i][0] & 0x100 ? 1 : -1;
code = s->core_downmix_codes[i][0] & 0x0FF;
s->downmix_coef[i][0] = (!code ? 0.0f :
@@ -1890,18 +1898,19 @@ FF_ENABLE_DEPRECATION_WARNINGS
"Invalid channel mode %d\n", am);
return AVERROR_INVALIDDATA;
}
- if (s->prim_channels > FF_ARRAY_ELEMS(dca_default_coeffs[0])) {
+ if (s->prim_channels + !!s->lfe >
+ FF_ARRAY_ELEMS(dca_default_coeffs[0])) {
avpriv_request_sample(s->avctx, "Downmixing %d channels",
- s->prim_channels);
+ s->prim_channels + !!s->lfe);
return AVERROR_PATCHWELCOME;
}
- for (i = 0; i < s->prim_channels; i++) {
+ for (i = 0; i < s->prim_channels + !!s->lfe; i++) {
s->downmix_coef[i][0] = dca_default_coeffs[am][i][0];
s->downmix_coef[i][1] = dca_default_coeffs[am][i][1];
}
}
av_dlog(s->avctx, "Stereo downmix coeffs:\n");
- for (i = 0; i < s->prim_channels; i++) {
+ for (i = 0; i < s->prim_channels + !!s->lfe; i++) {
av_dlog(s->avctx, "L, input channel %d = %f\n", i,
s->downmix_coef[i][0]);
av_dlog(s->avctx, "R, input channel %d = %f\n", i,
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