vp9-svc: Set downsampling filter for VGA layer.

Downsampling filter for SVC was set to subsample (phase 0)
for HD -> VGA, and bilinear averaging (phase 8) for VGA -> QVGA.
This change makes it bilinear averaging for HD -> VGA.

Given the recent commit 9f9d4f8, quality is improved with
this change: avgPSNR/SSIM up ~1-3% on HD clips in RTC set.
Speed decrease of ~1% for 3 layer SVC.

Change-Id: If834a320e372b8b922a6bf7cab4227703b1beae6
This commit is contained in:
Marco 2017-12-06 11:21:29 -08:00
parent 575c1933ea
commit 3562d6b0a2

View File

@ -656,9 +656,9 @@ int vp9_one_pass_cbr_svc_start_layer(VP9_COMP *const cpi) {
lc->scaling_factor_num, lc->scaling_factor_den, &width,
&height);
// For resolutions <= QVGA: set phase of the filter = 8 (for symmetric
// For resolutions <= VGA: set phase of the filter = 8 (for symmetric
// averaging filter), use bilinear for now.
if (width * height <= 320 * 240) {
if (width * height <= 640 * 480) {
cpi->svc.downsample_filter_type[cpi->svc.spatial_layer_id] = BILINEAR;
cpi->svc.downsample_filter_phase[cpi->svc.spatial_layer_id] = 8;
}