diff --git a/.gitignore b/.gitignore
index bad57703..db0e96e4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -22,3 +22,5 @@ liboptv/build
 py_bind/optv/*.c
 py_bind/build
 *.pyc
+liboptv/src/main
+liboptv/src/main
diff --git a/liboptv/CMakeLists.txt b/liboptv/CMakeLists.txt
index 2ad9312d..d51f7c3b 100644
--- a/liboptv/CMakeLists.txt
+++ b/liboptv/CMakeLists.txt
@@ -4,9 +4,9 @@ set (CMAKE_INSTALL_RPATH "$ORIGIN/../lib:$ORIGIN/")
 
 set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/CMakeModules/")
 project(OpenPTV)
-# enable_testing()
+enable_testing()
 add_subdirectory(src)
-# add_subdirectory(tests)
+add_subdirectory(tests)
 
 INSTALL(DIRECTORY include/ DESTINATION include/optv/)
 
diff --git a/liboptv/include/main.h b/liboptv/include/main.h
new file mode 100644
index 00000000..49ae8abc
--- /dev/null
+++ b/liboptv/include/main.h
@@ -0,0 +1,28 @@
+#ifndef main_h
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <math.h>
+#include <string.h>
+#include <inttypes.h>
+#include "tiffio.h"
+
+#include "parameters.h"
+#include "track.h"
+#include "image_processing.h"
+#include "segmentation.h"
+#include "tracking_frame_buf.h"
+#include "calibration.h"
+#include "vec_utils.h"
+#include "imgcoord.h"
+#include "trafo.h"
+#include "correspondences.h"
+
+
+
+#define main_h
+
+
+#endif /* main_h */
\ No newline at end of file
diff --git a/liboptv/src/main b/liboptv/src/main
new file mode 100755
index 00000000..9cad0fea
Binary files /dev/null and b/liboptv/src/main differ
diff --git a/liboptv/src/main.c b/liboptv/src/main.c
new file mode 100644
index 00000000..b66889a3
--- /dev/null
+++ b/liboptv/src/main.c
@@ -0,0 +1,275 @@
+/* main.c 
+I need this file to start preparing some structure in my head. Alex
+*/
+
+#define MAXTARGETS 2048
+#define BUFFER_LENGTH 4 // we do something very simple and studpid here
+#include "main.h"
+
+// These functions are part of the a test suite, see under /tests
+
+void read_all_calibration(Calibration *calib[4], control_par *cpar)
+{
+    char ori_tmpl[] = "cal/cam%d.tif.ori";
+    char added_name[] = "cal/cam1.tif.addpar";
+    char ori_name[40];
+    int cam;
+
+    for (cam = 0; cam < cpar->num_cams; cam++)
+    {
+        sprintf(ori_name, ori_tmpl, cam + 1);
+        calib[cam] = read_calibration(ori_name, added_name, NULL);
+    }
+}
+
+/*  correct_frame() performs the transition from pixel to metric to flat 
+    coordinates and x-sorting as required by the correspondence code.
+    
+    Arguments:
+    frame *frm - target information for all cameras.
+    control_par *cpar - parameters of image size, pixel size etc.
+    tol - tolerance parameter for iterative flattening phase, see 
+        trafo.h:correct_brown_affine_exact().
+*/
+coord_2d **correct_frame(frame *frm, Calibration *calib[], control_par *cpar,
+                         double tol)
+{
+    coord_2d **corrected, **tmp;
+    int cam, part;
+
+    corrected = (coord_2d **)malloc(cpar->num_cams * sizeof(coord_2d *));
+    tmp = (coord_2d **)malloc(cpar->num_cams * sizeof(coord_2d *));
+    for (cam = 0; cam < cpar->num_cams; cam++)
+    {
+        corrected[cam] = (coord_2d *)malloc(
+            frm->num_targets[cam] * sizeof(coord_2d));
+        tmp[cam] = (coord_2d *)malloc(frm->num_targets[cam] * sizeof(coord_2d));
+        if (corrected[cam] == NULL)
+        {
+            /* roll back allocations and fail */
+            for (cam -= 1; cam >= 0; cam--)
+                free(corrected[cam]);
+            free(corrected);
+            return NULL;
+        }
+
+        for (part = 0; part < frm->num_targets[cam]; part++)
+        {
+            pixel_to_metric(&tmp[cam][part].x, &tmp[cam][part].y,
+                            frm->targets[cam][part].x, frm->targets[cam][part].y,
+                            cpar);
+
+            dist_to_flat(tmp[cam][part].x, tmp[cam][part].y,
+                         calib[cam], &corrected[cam][part].x, &corrected[cam][part].y,
+                         tol);
+            corrected[cam][part].pnr = frm->targets[cam][part].pnr;
+        }
+
+        /* This is expected by find_candidate() */
+        quicksort_coord2d_x(corrected[cam], frm->num_targets[cam]);
+    }
+    return corrected;
+}
+
+// int main(int argc, const char *argv[])
+int main()
+{
+    // initialize variables
+
+    int i, cam, ntargets, step, lstep, geo_id;
+    coord_2d **corrected;
+    int match_counts[4];
+    n_tupel *corresp_buf;
+    tracking_run *run;
+    vec3d res;
+    vec2d targ[4],tmp;
+    framebuf *frm; 
+
+    // temporary variables will be replaced per particle 
+    corres t_corres = { 3, {96, 66, 26, 26} };
+    P t_path = {
+        .x = {45.219, -20.269, 25.946},
+        .prev = -1,
+        .next = -2,
+        .prio = 4,
+        .finaldecis = 1000000.0,
+        .inlist = 0.
+    };
+
+    // read parameters from the working directory
+    // for simplicity all names are default and hard coded (sorry)
+
+    // 1. process inputs: directory, first frame, last frame
+
+    // printf("This program was called with \"%s\".\n", argv[0]);
+
+    // argc = 4;
+
+    // argv[1] = '../tests/testing_fodder/test_cavity/';
+    // argv[2] = 10001;
+    // argv[3] = 10004;
+
+    // if (argc != 2 && argc != 4)
+    // {
+    //     printf("Wrong number of inputs, expecting: \n");
+    //     printf(" ./main ../tests/testing_fodder/test_cavity/ 10001 10004 \n");
+    //     return 0;
+    // }
+
+    // argv[1] = '../tests/testing_fodder/test_cavity/';
+    // argv[2] = 10001;
+    // argv[3] = 10004;
+
+    // change directory to the user-supplied working folder
+    // chdir(argv[1]);
+
+    // chdir("../tests/testing_fodder/test_cavity/");
+    chdir("/Users/alex/Documents/OpenPTV/test_cavity");
+    // chdir("/Users/alex/Documents/OpenPTV/one-dot-example/working_folder");
+
+    // printf("changed directory to %s\n", argv[1]);
+
+    // 2. read parameters and calibrations
+    Calibration *calib[4]; // sorry only for 4 cameras now
+
+    control_par *cpar = read_control_par("parameters/ptv.par");
+    read_all_calibration(calib, cpar);
+    free_control_par(cpar);
+
+    run = tr_new_legacy("parameters/sequence.par",
+                        "parameters/track.par", "parameters/criteria.par",
+                        "parameters/ptv.par", calib);
+
+
+    // if (argc == 4)
+    // {
+    //     run->seq_par->first = atoi(argv[2]);
+    //     run->seq_par->last = atoi(argv[3]);
+    // }
+    run->seq_par->first = 10000;
+    run->seq_par->last = 10004;
+
+    // printf("from frame %d to frame %d \n", run->seq_par->first, run->seq_par->last);
+
+    // for each camera and for each time step the images are processed
+    for (step = run->seq_par->first; step < run->seq_par->last + 1; step++)
+    {
+        lstep = step - run->seq_par->first; // local step
+         
+        for (cam = 0; cam < run->cpar->num_cams; cam++)
+        {
+            // we decided to focus camust on the _targets, so we will read them from the
+            // test directory test_cavity
+
+            run->fb->buf[lstep]->num_targets[cam] = read_targets(
+                run->fb->buf[lstep]->targets[cam], run->fb->target_file_base[cam], step);
+
+            quicksort_target_y(run->fb->buf[lstep]->targets[cam], run->fb->buf[lstep]->num_targets[cam]);
+
+            for (i = 0; i < run->fb->buf[lstep]->num_targets[cam]; i++)
+               run->fb->buf[lstep]->targets[cam][i].pnr = i;
+
+
+        } // inner loop is per camera
+        corrected = correct_frame(run->fb->buf[lstep], run->cal, run->cpar, 0.00001);
+        corresp_buf = correspondences(run->fb->buf[lstep], corrected, run->vpar, run->cpar, run->cal, match_counts);
+
+        run->fb->buf[lstep]->num_parts = match_counts[0];
+
+        // first we need to create 3d points after correspondences and fill it into the buffer
+        // use point_position and loop through the num_parts
+        // probably feed it directly into the buffer
+
+        // so we split into two parts:
+        // first i copy the code from correspondences.pyx
+        // and create the same types of arrays in C
+        // then we will convert those to 3D using similar approach to what is now in Python
+
+
+        // shortcut
+        int p[4];
+        double x,y;
+        float skew_dist; 
+
+        //printf("looks like rt_is.%d\n",step);
+
+        for (i=0; i<run->fb->buf[lstep]->num_parts; i++) {
+            for (cam = 0; cam < run->cpar->num_cams; cam++) {
+                if (corresp_buf[i].p[cam] > -1){  
+                    p[cam] = corrected[cam][corresp_buf[i].p[cam]].pnr;
+                    x = run->fb->buf[lstep]->targets[cam][p[cam]].x;
+                    y = run->fb->buf[lstep]->targets[cam][p[cam]].y;
+
+                    pixel_to_metric(&x, &y, x, y, run->cpar);
+                    dist_to_flat(x, y,run->cal[cam], &x, &y,0.00001);
+
+                    targ[cam][0] = x;  
+                    targ[cam][1] = y;       
+                }else{
+                    targ[cam][0] = 1e-10;
+                    targ[cam][1] = 1e-10;
+                }
+
+                t_corres.p[cam] = p[cam];
+            }
+
+                t_corres.nr = i+1; // identical to what I see in rt_is.10004 file
+                run->fb->buf[lstep]->correspond[i] = t_corres;
+                
+
+
+
+
+                skew_dist = point_position(targ, run->cpar->num_cams, run->cpar->mm, run->cal, res);
+
+                // printf("%d \t ",run->fb->buf[lstep]->correspond[i].nr);
+                // printf("%f,\t %f,\t %f\t ",res[0],res[1],res[2]);
+                // for (cam=0;cam<run->cpar->num_cams; cam++) {
+                //     printf("%d\t ",run->fb->buf[lstep]->correspond[i].p[cam]);
+                // }
+                // printf("\n");
+
+
+                t_path.x[0] = res[0];
+                t_path.x[1] = res[1];
+                t_path.x[2] = res[2];
+
+                run->fb->buf[lstep]->path_info[i] = t_path;
+            //}
+        }
+
+    } // external loop is through frames
+
+    run->tpar->add = 0; 
+    // we do not need to read frames - it's all in memory now
+    // track_forward_start(run); 
+
+    // for (step = run->seq_par->first + 1 ; step < run->seq_par->last; step++)
+    // // for (step = run->seq_par->first + 1; step < run->seq_par->last; step++)
+    // {
+    //     trackcorr_c_loop(run, step);
+    // }
+    // trackcorr_c_finish(run, run->seq_par->last);
+
+    trackcorr_c_loop(run, run->seq_par->first);
+
+    // probably here we need to send something to plot it
+    // or store in some memory for the next chunk?
+    // basically we have a human in the loop here - his/her brain
+    // will simply follow the velocity values in time like a movie
+    // and we will store it to binary files. Later if someone wants to do
+    // tracking, our simmple solution is not good enough. we kind of doing 3D-PIV here
+    // of 4 frames and show the vectors. The quasi-vectors are not really connected. if we
+    // will create nice animation - then the user will build tracamectories him/herself.
+
+    for (cam -= 1; cam >= 0; cam--)
+        free(corrected[cam]);
+
+    free(corrected);
+    free(corresp_buf);
+    free(run->vpar);
+    free_control_par(run->cpar);
+
+    return 0;
+
+} // should be end of main now
\ No newline at end of file
diff --git a/liboptv/src/multimed.c b/liboptv/src/multimed.c
index 2abe4388..84706211 100644
--- a/liboptv/src/multimed.c
+++ b/liboptv/src/multimed.c
@@ -104,7 +104,7 @@ double multimed_r_nlay (Calibration *cal, mm_np *mm, vec3d pos) {
 
  
     if (it >= n_iter) {
-        printf ("multimed_r_nlay stopped after %d iterations\n", n_iter);  
+        //printf ("multimed_r_nlay stopped after %d iterations\n", n_iter);  
         return (1.0);
     }
 
diff --git a/liboptv/src/tracking_frame_buf.c b/liboptv/src/tracking_frame_buf.c
index b2370fd4..e5c5939f 100644
--- a/liboptv/src/tracking_frame_buf.c
+++ b/liboptv/src/tracking_frame_buf.c
@@ -52,7 +52,7 @@ int read_targets(target buffer[], char* file_base, int frame_num) {
         strncpy(filein, file_base, STR_MAX_LEN);
         strncat(filein, "_targets", STR_MAX_LEN);
     }
-    
+
     FILEIN = fopen (filein, "r");
     if (! FILEIN) {
         printf("Can't open ascii file: %s\n", filein);
@@ -423,7 +423,7 @@ int write_path_frame(corres *cor_buf, P *path_buf, int num_parts,\
     return success;
 }
 
-/* init_frame() initializes a frame object, allocates its arrays and sets up 
+/* frame_init() initializes a frame object, allocates its arrays and sets up 
  * the frame data.
  *  
  * Arguments: