diff options
| author | Jean-Marc Valin <jmvalin@jmvalin.ca> | 2016-07-29 20:47:07 +0300 |
|---|---|---|
| committer | Jean-Marc Valin <jmvalin@jmvalin.ca> | 2016-07-30 00:32:29 +0300 |
| commit | ed6e3aff3a4eecf01364886547d02fa962efdcad (patch) | |
| tree | 7f2cc986aa0c7e299312bf13aefdd32bd97e993d | |
| parent | 54ba3f4f00a90229d1c2f6bd356626999bda1572 (diff) | |
biasing quantization
| -rw-r--r-- | celt/bands.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/celt/bands.c b/celt/bands.c index 82d17311..086f5bf2 100644 --- a/celt/bands.c +++ b/celt/bands.c @@ -742,11 +742,15 @@ static void compute_theta(struct band_ctx *ctx, struct split_ctx *sctx, if (encode) { if (!stereo || ctx->theta_round == 0) + { itheta = (itheta*(opus_int32)qn+8192)>>14; - else if (ctx->theta_round < 0) - itheta = (itheta*(opus_int32)qn)>>14; - else - itheta = (itheta*(opus_int32)qn+16383)>>14; + } else { + int qoffset = itheta > 8192 ? 16384/(qn+1) : -16384/(qn+1); + if (ctx->theta_round < 0) + itheta = IMAX(0, (itheta*(opus_int32)qn+qoffset)>>14); + else + itheta = IMIN(qn, (itheta*(opus_int32)qn+16383+qoffset)>>14); + } } /* Entropy coding of the angle. We use a uniform pdf for the time split, a step for stereo, and a triangular one for the rest. */ |