Aliased compressed AAC bytes are almost certainly not meaningful SBR
data. In the wild this causes harsh artifacts switching HE-AAC streams
that don't have SBR headers aligned with segment boundaries.
Turning off SBR falls back to a default set of upsampling parameters
that can function as a sort of error concealment. This is consistent
with how the decoder handles other sorts of errors.
if (bytes_read > cnt) {
av_log(ac->avctx, AV_LOG_ERROR,
"Expected to read %d SBR bytes actually read %d.\n", cnt, bytes_read);
+ sbr_turnoff(sbr);
}
return cnt;
}