From 3046935e03ec511353c2bffe79caf1a195cb2ac7 Mon Sep 17 00:00:00 2001
From: Wim Taymans <wtaymans@redhat.com>
Date: Wed, 25 Feb 2015 16:15:52 +0100
Subject: [PATCH] video-converter: activate scaler fastpath depending on method

Only activate the scaler fastpath for x2 up and downscale when the
scaler method is respectively nearest and linear because that is what
those fastpaths really implement.
---
 gst-libs/gst/video/video-converter.c | 27 +++++++++++++++++----------
 1 file changed, 17 insertions(+), 10 deletions(-)

diff --git a/gst-libs/gst/video/video-converter.c b/gst-libs/gst/video/video-converter.c
index b596e57..2c9d126 100644
--- a/gst-libs/gst/video/video-converter.c
+++ b/gst-libs/gst/video/video-converter.c
@@ -3948,6 +3948,7 @@ setup_scale (GstVideoConverter * convert)
       gint comp, n_comp, j, iw, ih, ow, oh, pstride;
       gboolean need_v_scaler, need_h_scaler;
       GstStructure *config;
+      gint resample_method;
 
       n_comp = GST_VIDEO_FORMAT_INFO_N_COMPONENTS (in_finfo);
 
@@ -4016,16 +4017,20 @@ setup_scale (GstVideoConverter * convert)
 
       config = gst_structure_copy (convert->config);
 
+      resample_method = (i == 0 ? method : cr_method);
+
       need_v_scaler = FALSE;
       need_h_scaler = FALSE;
       if (iw == ow) {
         if (ih == oh) {
           convert->fconvert[i] = convert_plane_copy;
           GST_DEBUG ("plane %d: copy", i);
-        } else if (ih == 2 * oh && pstride == 1) {
+        } else if (ih == 2 * oh && pstride == 1
+            && resample_method == GST_VIDEO_RESAMPLER_METHOD_LINEAR) {
           convert->fconvert[i] = convert_plane_v_halve;
           GST_DEBUG ("plane %d: vertical halve", i);
-        } else if (2 * ih == oh && pstride == 1) {
+        } else if (2 * ih == oh && pstride == 1
+            && resample_method == GST_VIDEO_RESAMPLER_METHOD_NEAREST) {
           convert->fconvert[i] = convert_plane_v_double;
           GST_DEBUG ("plane %d: vertical double", i);
         } else {
@@ -4034,10 +4039,12 @@ setup_scale (GstVideoConverter * convert)
           need_v_scaler = TRUE;
         }
       } else if (ih == oh) {
-        if (iw == 2 * ow && pstride == 1) {
+        if (iw == 2 * ow && pstride == 1
+            && resample_method == GST_VIDEO_RESAMPLER_METHOD_LINEAR) {
           convert->fconvert[i] = convert_plane_h_halve;
           GST_DEBUG ("plane %d: horizontal halve", i);
-        } else if (2 * iw == ow && pstride == 1) {
+        } else if (2 * iw == ow && pstride == 1
+            && resample_method == GST_VIDEO_RESAMPLER_METHOD_NEAREST) {
           convert->fconvert[i] = convert_plane_h_double;
           GST_DEBUG ("plane %d: horizontal double", i);
         } else {
@@ -4046,10 +4053,12 @@ setup_scale (GstVideoConverter * convert)
           need_h_scaler = TRUE;
         }
       } else {
-        if (iw == 2 * ow && ih == 2 * oh && pstride == 1) {
+        if (iw == 2 * ow && ih == 2 * oh && pstride == 1
+            && resample_method == GST_VIDEO_RESAMPLER_METHOD_LINEAR) {
           convert->fconvert[i] = convert_plane_hv_halve;
           GST_DEBUG ("plane %d: horizontal/vertical halve", i);
-        } else if (2 * iw == ow && 2 * ih == oh && pstride == 1) {
+        } else if (2 * iw == ow && 2 * ih == oh && pstride == 1
+            && resample_method == GST_VIDEO_RESAMPLER_METHOD_NEAREST) {
           convert->fconvert[i] = convert_plane_hv_double;
           GST_DEBUG ("plane %d: horizontal/vertical double", i);
         } else {
@@ -4061,15 +4070,13 @@ setup_scale (GstVideoConverter * convert)
       }
 
       if (need_h_scaler) {
-        convert->fh_scaler[i] =
-            gst_video_scaler_new (i == 0 ? method : cr_method,
+        convert->fh_scaler[i] = gst_video_scaler_new (resample_method,
             GST_VIDEO_SCALER_FLAG_NONE, taps, iw, ow, config);
       } else
         convert->fh_scaler[i] = NULL;
 
       if (need_v_scaler) {
-        convert->fv_scaler[i] =
-            gst_video_scaler_new (i == 0 ? method : cr_method,
+        convert->fv_scaler[i] = gst_video_scaler_new (resample_method,
             GST_VIDEO_SCALER_FLAG_NONE, taps, ih, oh, config);
         gst_video_scaler_get_coeff (convert->fv_scaler[i], 0, NULL, &n_taps);
       } else
-- 
2.7.4