1 files changed, 32 insertions, 21 deletions

diff --git a/tools/speed_stats.cc b/tools/speed_stats.cc
index 2aea8a0..cdef814 100644
--- a/tools/speed_stats.cc
+++ b/tools/speed_stats.cc
@@ -5,6 +5,7 @@
 
 #include "tools/speed_stats.h"
 
+#include <inttypes.h>
 #include <math.h>
 #include <stddef.h>
 #include <stdio.h>
@@ -12,18 +13,17 @@
 #include <algorithm>
 #include <string>
 
-#include "lib/jxl/base/robust_statistics.h"
-
 namespace jpegxl {
 namespace tools {
 
 void SpeedStats::NotifyElapsed(double elapsed_seconds) {
-  JXL_ASSERT(elapsed_seconds > 0.0);
-  elapsed_.push_back(elapsed_seconds);
+  if (elapsed_seconds > 0.0) {
+    elapsed_.push_back(elapsed_seconds);
+  }
 }
 
-jxl::Status SpeedStats::GetSummary(SpeedStats::Summary* s) {
-  if (elapsed_.empty()) return JXL_FAILURE("Didn't call NotifyElapsed");
+bool SpeedStats::GetSummary(SpeedStats::Summary* s) {
+  if (elapsed_.empty()) return false;
 
   s->min = *std::min_element(elapsed_.begin(), elapsed_.end());
   s->max = *std::max_element(elapsed_.begin(), elapsed_.end());
@@ -45,23 +45,30 @@ jxl::Status SpeedStats::GetSummary(SpeedStats::Summary* s) {
   }
 
   // Prefer geomean unless numerically unreliable (too many reps)
-  if (std::pow(elapsed_[0], elapsed_.size()) < 1E100) {
+  if (pow(elapsed_[0], elapsed_.size()) < 1E100) {
     double product = 1.0;
     for (size_t i = 1; i < elapsed_.size(); ++i) {
       product *= elapsed_[i];
     }
 
-    s->central_tendency = std::pow(product, 1.0 / (elapsed_.size() - 1));
+    s->central_tendency = pow(product, 1.0 / (elapsed_.size() - 1));
     s->variability = 0.0;
     s->type = " geomean:";
     return true;
   }
 
-  // Else: mode
+  // Else: median
   std::sort(elapsed_.begin(), elapsed_.end());
-  s->central_tendency = jxl::HalfSampleMode()(elapsed_.data(), elapsed_.size());
-  s->variability = jxl::MedianAbsoluteDeviation(elapsed_, s->central_tendency);
-  s->type = "mode: ";
+  s->central_tendency = elapsed_.data()[elapsed_.size() / 2];
+  std::vector<double> deviations(elapsed_.size());
+  for (size_t i = 0; i < elapsed_.size(); i++) {
+    deviations[i] = fabs(elapsed_[i] - s->central_tendency);
+  }
+  std::nth_element(deviations.begin(),
+                   deviations.begin() + deviations.size() / 2,
+                   deviations.end());
+  s->variability = deviations[deviations.size() / 2];
+  s->type = "median: ";
   return true;
 }
 
@@ -77,18 +84,18 @@ std::string SummaryStat(double value, const char* unit,
   const double value_min = value / s.max;
   const double value_max = value / s.min;
 
-  int ret = snprintf(stat_str, sizeof(stat_str), ",%s %.2f %s/s [%.2f, %.2f]",
-                     s.type, value_tendency, unit, value_min, value_max);
-  (void)ret;  // ret is unused when JXL_ASSERT is disabled.
-  JXL_ASSERT(ret < static_cast<int>(sizeof(stat_str)));
+  snprintf(stat_str, sizeof(stat_str), ",%s %.2f %s/s [%.2f, %.2f]", s.type,
+           value_tendency, unit, value_min, value_max);
   return stat_str;
 }
 
 }  // namespace
 
-jxl::Status SpeedStats::Print(size_t worker_threads) {
+bool SpeedStats::Print(size_t worker_threads) {
   Summary s;
-  JXL_RETURN_IF_ERROR(GetSummary(&s));
+  if (!GetSummary(&s)) {
+    return false;
+  }
   std::string mps_stats = SummaryStat(xsize_ * ysize_ * 1e-6, "MP", s);
   std::string mbs_stats = SummaryStat(file_size_ * 1e-6, "MB", s);
 
@@ -97,9 +104,13 @@ jxl::Status SpeedStats::Print(size_t worker_threads) {
     snprintf(variability, sizeof(variability), " (var %.2f)", s.variability);
   }
 
-  fprintf(stderr, "%zu x %zu%s%s%s, %zu reps, %zu threads.\n", xsize_, ysize_,
-          mps_stats.c_str(), mbs_stats.c_str(), variability, elapsed_.size(),
-          worker_threads);
+  fprintf(stderr,
+          "%" PRIu64 " x %" PRIu64 "%s%s%s, %" PRIu64 " reps, %" PRIu64
+          " threads.\n",
+          static_cast<uint64_t>(xsize_), static_cast<uint64_t>(ysize_),
+          mps_stats.c_str(), mbs_stats.c_str(), variability,
+          static_cast<uint64_t>(elapsed_.size()),
+          static_cast<uint64_t>(worker_threads));
   return true;
 }