This commit adds support for the coding of intensity stereo spectral
coefficients. It also fixes the Mid/Side coding of band_types higher than
RESERVED_BT (M/S must not be applied to their spectral coefficients, but
marking M/S as present in encode_ms_info() is okay). Much of the changes here
were taken from the decoder and inverted. This commit does not change the
functionality of the decoder as the previous patch in this series zeroes
ms_mask and is_mask.
Reviewed-by: Claudio Freire <klaussfre...@gmail.com>
---
libavcodec/aacenc.c | 37 +++++++++++++++++++++++++++----------
1 file changed, 27 insertions(+), 10 deletions(-)
diff --git a/libavcodec/aacenc.c b/libavcodec/aacenc.c
index f7325d4..3e5ac72 100644
--- a/libavcodec/aacenc.c
+++ b/libavcodec/aacenc.c
@@ -312,19 +312,26 @@ static void encode_ms_info(PutBitContext *pb,
ChannelElement *cpe)
static void adjust_frame_information(ChannelElement *cpe, int chans)
{
int i, w, w2, g, ch;
- int start, maxsfb, cmaxsfb;
+ int maxsfb, cmaxsfb;
+ IndividualChannelStream *ics;
- for (ch = 0; ch < chans; ch++) {
- IndividualChannelStream *ics = &cpe->ch[ch].ics;
- start = 0;
- maxsfb = 0;
- cpe->ch[ch].pulse.num_pulse = 0;
+ if (cpe->common_window) {
+ ics = &cpe->ch[0].ics;
for (w = 0; w < ics->num_windows; w += ics->group_len[w]) {
- for (w2 = 0; w2 < ics->group_len[w]; w2++) {
- start = (w+w2) * 128;
+ for (w2 = 0; w2 < ics->group_len[w]; w2++) {
+ int start = (w+w2) * 128;
for (g = 0; g < ics->num_swb; g++) {
- //apply M/S
- if (cpe->common_window && !ch && cpe->ms_mask[w*16 + g]) {
+ //apply Intensity stereo coeffs transformation
+ if (cpe->is_mask[w*16 + g]) {
+ int p = -1 + 2 * (cpe->ch[1].band_type[w*16+g] - 14);
+ float scale = cpe->ch[0].is_ener[w*16+g];
+ for (i = 0; i < ics->swb_sizes[g]; i++) {
+ cpe->ch[0].coeffs[start+i] =
(cpe->ch[0].pcoeffs[start+i] + p*cpe->ch[1].pcoeffs[start+i]) * scale;
+ cpe->ch[1].coeffs[start+i] = 0.0f;
+ }
+ } else if (cpe->ms_mask[w*16 + g] &&
+ cpe->ch[0].band_type[w*16 + g] < NOISE_BT &&
+ cpe->ch[1].band_type[w*16 + g] < NOISE_BT) {
for (i = 0; i < ics->swb_sizes[g]; i++) {
cpe->ch[0].coeffs[start+i] =
(cpe->ch[0].pcoeffs[start+i] + cpe->ch[1].pcoeffs[start+i]) * 0.5f;
cpe->ch[1].coeffs[start+i] =
cpe->ch[0].coeffs[start+i] - cpe->ch[1].pcoeffs[start+i];
@@ -332,6 +339,16 @@ static void adjust_frame_information(ChannelElement *cpe,
int chans)
}
start += ics->swb_sizes[g];
}
+ }
+ }
+ }
+
+ for (ch = 0; ch < chans; ch++) {
+ IndividualChannelStream *ics = &cpe->ch[ch].ics;
+ maxsfb = 0;
+ cpe->ch[ch].pulse.num_pulse = 0;
+ for (w = 0; w < ics->num_windows; w += ics->group_len[w]) {
+ for (w2 = 0; w2 < ics->group_len[w]; w2++) {
for (cmaxsfb = ics->num_swb; cmaxsfb > 0 &&
cpe->ch[ch].zeroes[w*16+cmaxsfb-1]; cmaxsfb--)
;
maxsfb = FFMAX(maxsfb, cmaxsfb);
--
2.1.4
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
