[Feature] Add images normalization

diff --git a/src/libmime/images.c b/src/libmime/images.c
index 86e63e3663c3b3ece6ca02a4566d178a9018514e..7e2185f57082b1bbf9e1f4cba10c05ad77d27957 100644 (file)
--- a/src/libmime/images.c
+++ b/src/libmime/images.c
@@ -19,6 +19,12 @@
 #include "message.h"
 #include "html.h"
 
+#ifdef WITH_GD
+#include "gd.h"
+
+#define RSPAMD_NORMALIZED_DIM 64
+#endif
+
 static const guint8 png_signature[] = {137, 80, 78, 71, 13, 10, 26, 10};
 static const guint8 jpg_sig1[] = {0xff, 0xd8};
 static const guint8 jpg_sig_jfif[] = {0xff, 0xe0};
@@ -202,6 +208,82 @@ process_bmp_image (struct rspamd_task *task, GByteArray *data)
        return img;
 }
 
+static void
+rspamd_image_normalize (struct rspamd_task *task, struct rspamd_image *img)
+{
+#ifdef WITH_GD
+       gdImagePtr src = NULL, dst = NULL;
+       guint nw, nh, i, j;
+
+       if (img->data->len == 0 || img->data->len > G_MAXINT32) {
+               return;
+       }
+
+       if (img->height <= RSPAMD_NORMALIZED_DIM ||
+                       img->width <= RSPAMD_NORMALIZED_DIM) {
+               return;
+       }
+
+       switch (img->type) {
+       case IMAGE_TYPE_JPG:
+               src = gdImageCreateFromJpegPtr (img->data->len, img->data->data);
+               break;
+       case IMAGE_TYPE_PNG:
+               src = gdImageCreateFromPngPtr (img->data->len, img->data->data);
+               break;
+       case IMAGE_TYPE_GIF:
+               src = gdImageCreateFromGifPtr (img->data->len, img->data->data);
+               break;
+       case IMAGE_TYPE_BMP:
+               src = gdImageCreateFromBmpPtr (img->data->len, img->data->data);
+               break;
+       default:
+               return;
+       }
+
+       if (src == NULL) {
+               msg_info_task ("cannot load image of type %s from %s",
+                               rspamd_image_type_str (img->type), img->filename);
+       }
+       else {
+               gdImageSetInterpolationMethod (src, GD_BILINEAR_FIXED);
+               nw = img->width;
+               nh = img->height;
+
+               if (nh > RSPAMD_NORMALIZED_DIM) {
+                       nw = nw * RSPAMD_NORMALIZED_DIM / nh;
+                       nw = nw ? nw : 1;
+                       nh = RSPAMD_NORMALIZED_DIM;
+               }
+
+               if (nw > RSPAMD_NORMALIZED_DIM) {
+                       nh = nh * RSPAMD_NORMALIZED_DIM / nw;
+                       nh = nh ? nh : 1;
+                       nw = RSPAMD_NORMALIZED_DIM;
+               }
+
+               dst = gdImageScale (src, nw, nh);
+               gdImageGrayScale (dst);
+               gdImageDestroy (src);
+
+               img->normalized_data = g_array_new (FALSE, FALSE, sizeof (gint));
+               g_array_set_size (img->normalized_data, nh * nw);
+
+               for (i = 0; i < nh; i ++) {
+                       for (j = 0; j < nw; j ++) {
+                               gint px = gdImageGetPixel (dst, j, i);
+
+                               g_array_append_val (img->normalized_data, px);
+                       }
+               }
+
+               gdImageDestroy (dst);
+               rspamd_mempool_add_destructor (task->task_pool, rspamd_array_free_hard,
+                               img->normalized_data);
+       }
+#endif
+}
+
 static void
 process_image (struct rspamd_task *task, struct rspamd_mime_part *part)
 {
@@ -241,6 +323,7 @@ process_image (struct rspamd_task *task, struct rspamd_mime_part *part)
                        task->message_id);
                img->filename = part->filename;
                img->parent = part;
+               rspamd_image_normalize (task, img);
                part->flags |= RSPAMD_MIME_PART_IMAGE;
                part->specific_data = img;
 

diff --git a/src/libmime/images.h b/src/libmime/images.h
index 73e00aebd34e8937acf8c95bbef8abe36ee56713..35833b6af186d7a9f15ea3aeceb3b2ef26d4ef37 100644 (file)
--- a/src/libmime/images.h
+++ b/src/libmime/images.h
@@ -18,6 +18,7 @@ enum rspamd_image_type {
 struct rspamd_image {
        struct rspamd_mime_part *parent;
        GByteArray *data;
+       GArray *normalized_data;
        const gchar *filename;
        struct html_image *html_image;
        enum rspamd_image_type type;