From 5a49c1d962895b4b2835ae47201d6b07e669153b Mon Sep 17 00:00:00 2001
From: Joseph Redmon <pjreddie@gmail.com>
Date: Thu, 9 Apr 2015 23:00:33 -0700
Subject: [PATCH] rotation

---
 src/data.c     |  8 ++++++--
 src/image.c    | 29 ++++++++++++++++++++++-------
 src/image.h    |  3 ++-
 src/imagenet.c |  7 +++++++
 4 files changed, 37 insertions(+), 10 deletions(-)

diff --git a/src/data.c b/src/data.c
index c454d84c..34108f6d 100644
--- a/src/data.c
+++ b/src/data.c
@@ -57,6 +57,12 @@ matrix load_image_paths(char **paths, int n, int w, int h)
 
     for(i = 0; i < n; ++i){
         image im = load_image_color(paths[i], w, h);
+        translate_image(im, -128);
+        scale_image(im, 1./128);
+        float rad = rand_uniform() - .5;
+        image rot = rotate_image(im, rad);
+        free_image(im);
+        im = rot;
         X.vals[i] = im.data;
         X.cols = im.h*im.w*im.c;
     }
@@ -373,8 +379,6 @@ void *load_in_thread(void *ptr)
 {
     struct load_args a = *(struct load_args*)ptr;
     *a.d = load_data(a.paths, a.n, a.m, a.labels, a.k, a.w, a.h);
-    translate_data_rows(*a.d, -128);
-    scale_data_rows(*a.d, 1./128);
     free(ptr);
     return 0;
 }
diff --git a/src/image.c b/src/image.c
index 32a51cc5..d85a054d 100644
--- a/src/image.c
+++ b/src/image.c
@@ -1,6 +1,7 @@
 #include "image.h"
 #include "utils.h"
 #include <stdio.h>
+#include <math.h>
 
 int windows = 0;
 
@@ -256,16 +257,23 @@ image float_to_image(int w, int h, int c, float *data)
     return out;
 }
 
-void rotate_image(image m)
+image rotate_image(image im, float rad)
 {
-    int i,j;
-    for(j = 0; j < m.c; ++j){
-        for(i = 0; i < m.h*m.w/2; ++i){
-            float swap = m.data[j*m.h*m.w + i];
-            m.data[j*m.h*m.w + i] = m.data[j*m.h*m.w + (m.h*m.w-1 - i)];
-            m.data[j*m.h*m.w + (m.h*m.w-1 - i)] = swap;
+    int x, y, c;
+    float cx = im.w/2.;
+    float cy = im.h/2.;
+    image rot = make_image(im.w, im.h, im.c);
+    for(c = 0; c < im.c; ++c){
+        for(y = 0; y < im.h; ++y){
+            for(x = 0; x < im.w; ++x){
+                float rx = cos(rad)*(x-cx) - sin(rad)*(y-cy) + cx;
+                float ry = sin(rad)*(x-cx) + cos(rad)*(y-cy) + cy;
+                float val = billinear_interpolate(im, rx, ry, c);
+                set_pixel(rot, x, y, c, val);
+            }
         }
     }
+    return rot;
 }
 
 void translate_image(image m, float s)
@@ -358,15 +366,22 @@ image resize_image(image im, int w, int h)
 void test_resize(char *filename)
 {
     image im = load_image(filename, 0,0);
+    translate_image(im, -128);
     image small = resize_image(im, 65, 63);
     image big = resize_image(im, 513, 512);
     image crop = crop_image(im, 50, 10, 100, 100);
     image crop2 = crop_image(im, -30, -50, 291, 400);
+    image rot = rotate_image(big, .02);
+    image rot2 = rotate_image(big, 3.14159265/2.);
+    image test = rotate_image(im, .6);
     show_image(im, "original");
     show_image(small, "smaller");
     show_image(big, "bigger");
     show_image(crop, "crop");
     show_image(crop2, "crop2");
+    show_image(rot, "rot");
+    show_image(rot2, "rot2");
+    show_image(test, "test");
     cvWaitKey(0);
 }
 
diff --git a/src/image.h b/src/image.h
index a0d1875e..66262d81 100644
--- a/src/image.h
+++ b/src/image.h
@@ -20,7 +20,7 @@ image crop_image(image im, int dx, int dy, int w, int h);
 image resize_image(image im, int w, int h);
 void translate_image(image m, float s);
 void normalize_image(image p);
-void rotate_image(image m);
+image rotate_image(image m, float rad);
 void embed_image(image source, image dest, int dx, int dy);
 
 image collapse_image_layers(image source, int border);
@@ -47,6 +47,7 @@ image ipl_to_image(IplImage* src);
 float get_pixel(image m, int x, int y, int c);
 float get_pixel_extend(image m, int x, int y, int c);
 void set_pixel(image m, int x, int y, int c, float val);
+float billinear_interpolate(image im, float x, float y, int c);
 
 image get_image_layer(image m, int l);
 
diff --git a/src/imagenet.c b/src/imagenet.c
index 8a4ebcb3..9e993302 100644
--- a/src/imagenet.c
+++ b/src/imagenet.c
@@ -29,6 +29,13 @@ void train_imagenet(char *cfgfile, char *weightfile)
         time=clock();
         pthread_join(load_thread, 0);
         train = buffer;
+
+/*
+        image im = float_to_image(256, 256, 3, train.X.vals[114]);
+        show_image(im, "training");
+        cvWaitKey(0);
+        */
+
         load_thread = load_data_thread(paths, imgs, plist->size, labels, 1000, 256, 256, &buffer);
         printf("Loaded: %lf seconds\n", sec(clock()-time));
         time=clock();