libvmaf/integer_motion: fix subsample

Author: kylophone

libvmaf/src/feature/integer_motion.c

@@ -18,6 +18,7 @@
 
 
 #include <errno.h>
+#include <limits.h>
 #include <stddef.h>
 #include <stdlib.h>
 #include <string.h>
@@ -59,6 +60,7 @@ typedef struct MotionState {
     bool motion_moving_average;
     bool motion_force_zero;
     bool debug;
+    unsigned last_index;
     VmafDictionary *feature_name_dict;
 } MotionState;
 
@@ -267,6 +269,8 @@ static int init(VmafFeatureExtractor *fex, enum VmafPixelFormat pix_fmt,
     s->y_row = malloc(sizeof(*s->y_row) * w);
     if (!s->y_row) return -ENOMEM;
 
+    s->last_index = UINT_MAX;
+
     if (bpc == 8)
         s->pipeline = motion_score_pipeline_8;
     else
@@ -333,6 +337,8 @@ static int extract(VmafFeatureExtractor *fex,
             "VMAF_integer_feature_motion_sad_score", score, index);
     if (err) return err;
 
+    s->last_index = index;
+
     if (s->debug) {
         return vmaf_feature_collector_append_with_dict(feature_collector,
                 s->feature_name_dict,
@@ -362,18 +368,13 @@ static int flush(VmafFeatureExtractor *fex,
 
     const char *sad_name = "VMAF_integer_feature_motion_sad_score";
 
-    unsigned n_frames = 0;
-    double dummy;
-    while (!vmaf_feature_collector_get_score(feature_collector,
-            sad_name, &dummy, n_frames))
-        n_frames++;
-
+    if (s->last_index == UINT_MAX) return 1;
+    const unsigned n = s->last_index + 1;
     const unsigned stride = s->motion_five_frame_window ? 2 : 1;
     const unsigned min_idx = s->motion_five_frame_window ? 2 : 1;
-    if (n_frames == 0) return 1;
 
     double stamp_value = 0.;
-    if (n_frames > min_idx) {
+    if (n > min_idx) {
         double sad_at_min_idx;
         if (!vmaf_feature_collector_get_score(feature_collector, sad_name,
                                               &sad_at_min_idx, min_idx)) {
@@ -385,21 +386,26 @@ static int flush(VmafFeatureExtractor *fex,
     }
 
     double prev_processed = 0.;
-    for (unsigned i = 0; i < n_frames; i++) {
+    for (unsigned i = 0; i < n; i++) {
+        double sad_i;
+        vmaf_feature_collector_get_score(feature_collector, sad_name, &sad_i, i);
+
         double motion2;
 
         if (i < min_idx) {
             motion2 = 0.;
-        } else if (i == n_frames - 1) {
-            vmaf_feature_collector_get_score(feature_collector, sad_name, &motion2, i);
         } else {
             const int lo_idx = (int)i - (int)(stride - 1);
             const int hi_idx = (int)i + 1;
             double hi;
-            vmaf_feature_collector_get_score(feature_collector, sad_name, &hi, hi_idx);
-            if (lo_idx >= (int)min_idx) {
+            const bool has_hi = !vmaf_feature_collector_get_score(
+                    feature_collector, sad_name, &hi, hi_idx);
+            if (!has_hi) {
+                motion2 = sad_i;
+            } else if (lo_idx >= (int)min_idx) {
                 double lo;
-                vmaf_feature_collector_get_score(feature_collector, sad_name, &lo, lo_idx);
+                vmaf_feature_collector_get_score(
+                        feature_collector, sad_name, &lo, lo_idx);
                 motion2 = lo < hi ? lo : hi;
             } else {
                 motion2 = hi;

libvmaf/src/libvmaf.c

@@ -507,8 +507,12 @@ static void threaded_extract_batch_func(void *e, void **thread_data)
         if (fex->flags & VMAF_FEATURE_EXTRACTOR_TEMPORAL)
             continue;
 
-        if ((f->n_subsample > 1) && (f->index % f->n_subsample))
-            continue;
+        const uint64_t no_subsample_flags =
+            VMAF_FEATURE_EXTRACTOR_TEMPORAL | VMAF_FEATURE_EXTRACTOR_PREV_REF;
+        if (!(fex->flags & no_subsample_flags)) {
+            if ((f->n_subsample > 1) && (f->index % f->n_subsample))
+                continue;
+        }
 
         if (!td->fex_ctx[i]) {
             VmafDictionary *opts_dict = f->registered_fex->fex_ctx[i]->opts_dict;
@@ -854,7 +858,9 @@ int vmaf_read_pictures(VmafContext *vmaf, VmafPicture *ref, VmafPicture *dist,
         VmafFeatureExtractorContext *fex_ctx =
             vmaf->registered_feature_extractors.fex_ctx[i];
 
-        if (!(fex_ctx->fex->flags & VMAF_FEATURE_EXTRACTOR_TEMPORAL)) {
+        const uint64_t no_subsample_flags =
+            VMAF_FEATURE_EXTRACTOR_TEMPORAL | VMAF_FEATURE_EXTRACTOR_PREV_REF;
+        if (!(fex_ctx->fex->flags & no_subsample_flags)) {
             if ((vmaf->cfg.n_subsample > 1) && (index % vmaf->cfg.n_subsample))
                 continue;
         }