aacenc: Fix the conditions under which 3GPP pre-echo control is run.

According to the 3GPP spec:
"Thus the pre-echo control is inactive for the first short window (but
not all short windows in a short frame) after a start block and for
all frames with a stop window sequence."

Currently, pre-echo control is only run when the current frame is not
a short frame, and the previous frame is not a short frame.

patch by Nathan Caldwell saintdev (at) gmail

Originally committed as revision 25587 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Nathan Caldwell 2010-10-27 05:54:41 +00:00 committed by Anton Khirnov
parent 042ca05f0f
commit eafadadaf5

View File

@ -420,7 +420,7 @@ static void psy_3gpp_analyze(FFPsyContext *ctx, int channel,
band[g].thr = FFMAX(band[g].thr, band[g+1].thr * coeffs->spread_hi [g]); band[g].thr = FFMAX(band[g].thr, band[g+1].thr * coeffs->spread_hi [g]);
for (g = 0; g < num_bands; g++) { for (g = 0; g < num_bands; g++) {
band[g].thr_quiet = FFMAX(band[g].thr, coeffs->ath[g]); band[g].thr_quiet = FFMAX(band[g].thr, coeffs->ath[g]);
if (wi->num_windows != 8 && wi->window_type[1] != EIGHT_SHORT_SEQUENCE) if (!(wi->window_type[0] == LONG_STOP_SEQUENCE || (wi->window_type[1] == LONG_START_SEQUENCE && !w)))
band[g].thr_quiet = FFMAX(PSY_3GPP_RPEMIN*band[g].thr_quiet, band[g].thr_quiet = FFMAX(PSY_3GPP_RPEMIN*band[g].thr_quiet,
FFMIN(band[g].thr_quiet, FFMIN(band[g].thr_quiet,
PSY_3GPP_RPELEV*pch->prev_band[w+g].thr_quiet)); PSY_3GPP_RPELEV*pch->prev_band[w+g].thr_quiet));