diff --git a/tools/CompressionBenchmark.cpp b/tools/CompressionBenchmark.cpp
index b003faa7..5bb92f83 100644
--- a/tools/CompressionBenchmark.cpp
+++ b/tools/CompressionBenchmark.cpp
@@ -12,13 +12,15 @@
 #include "JFJochDecompress.h"
 
 double CheckCompressionThread(const DiffractionExperiment &x,
-                              int32_t nimages, int32_t stride,
+                              int32_t nimages,
+                              int32_t image0,
+                              int32_t stride,
                               const std::vector<int16_t> &image,
                               std::vector<uint16_t> &output) {
     double ret = 0;
 
     FrameTransformation transformation(x);
-    for (int i = 0; i < nimages; i += stride) {
+    for (int32_t i = image0; i < nimages; i += stride) {
         for (int j = 0; j < x.GetModulesNum(); j++ ) {
             transformation.ProcessModule(image.data() + (j + i * x.GetModulesNum()) * RAW_MODULE_SIZE, j, 0);
         }
@@ -40,7 +42,8 @@ std::string CheckCompression(const DiffractionExperiment &x, int32_t nimages, co
     std::vector<std::future<double>> futures;
 
     for (int i = 0; i < nthreads; i++)
-        futures.emplace_back(std::async(std::launch::async, &CheckCompressionThread, std::ref(x), nimages, nthreads,
+        futures.emplace_back(std::async(std::launch::async, &CheckCompressionThread, std::ref(x),
+                                        nimages, i, nthreads,
                                         std::ref(image), std::ref(output)));
 
     for (int i = 0; i < nthreads; i++)