diff --git a/libfprint/Makefile.am b/libfprint/Makefile.am
index b86d0f8..6685665 100644
--- a/libfprint/Makefile.am
+++ b/libfprint/Makefile.am
@@ -48,6 +48,8 @@ EXTRA_DIST = \
 	drivers/aes3k.h 	\
 	drivers/driver_ids.h	\
 	aeslib.c aeslib.h	\
+	assembling.c		\
+	assembling.h		\
 	pixman.c		\
 	60-fprint-autosuspend.rules
 
@@ -210,6 +212,8 @@ libfprint_la_SOURCES =	\
 	imgdev.c	\
 	poll.c		\
 	sync.c		\
+	assembling.c	\
+	assembling.h	\
 	$(DRIVER_SRC)	\
 	$(OTHER_SRC)	\
 	$(NBIS_SRC)
diff --git a/libfprint/aeslib.c b/libfprint/aeslib.c
index 8c0381a..978454d 100644
--- a/libfprint/aeslib.c
+++ b/libfprint/aeslib.c
@@ -26,6 +26,7 @@
 #include <glib.h>
 
 #include "fp_internal.h"
+#include "assembling.h"
 #include "aeslib.h"
 
 #define MAX_REGWRITES_PER_REQUEST	16
@@ -158,268 +159,16 @@ void aes_write_regv(struct fp_img_dev *dev, const struct aes_regwrite *regs,
 	continue_write_regv(wdata);
 }
 
-static inline unsigned char aes_get_pixel(struct aes_stripe *frame,
+unsigned char aes_get_pixel(struct fpi_frame_asmbl_ctx *ctx,
+					  struct fpi_frame *frame,
 					  unsigned int x,
-					  unsigned int y,
-					  unsigned int frame_width,
-					  unsigned int frame_height)
+					  unsigned int y)
 {
 	unsigned char ret;
 
-	ret = frame->data[x * (frame_height >> 1) + (y >> 1)];
+	ret = frame->data[x * (ctx->frame_height >> 1) + (y >> 1)];
 	ret = y % 2 ? ret >> 4 : ret & 0xf;
 	ret *= 17;
 
 	return ret;
 }
-
-static unsigned int calc_error(struct aes_stripe *first_frame,
-			       struct aes_stripe *second_frame,
-			       int dx,
-			       int dy,
-			       unsigned int frame_width,
-			       unsigned int frame_height)
-{
-	unsigned int width, height;
-	unsigned int x1, y1, x2, y2, err, i, j;
-
-	width = frame_width - (dx > 0 ? dx : -dx);
-	height = frame_height - dy;
-
-	y1 = 0;
-	y2 = dy;
-	i = 0;
-	err = 0;
-	do {
-		x1 = dx < 0 ? 0 : dx;
-		x2 = dx < 0 ? -dx : 0;
-		j = 0;
-
-		do {
-			unsigned char v1, v2;
-
-
-			v1 = aes_get_pixel(first_frame, x1, y1, frame_width, frame_height);
-			v2 = aes_get_pixel(second_frame, x2, y2, frame_width, frame_height);
-			err += v1 > v2 ? v1 - v2 : v2 - v1;
-			j++;
-			x1++;
-			x2++;
-
-		} while (j < width);
-		i++;
-		y1++;
-		y2++;
-	} while (i < height);
-
-	/* Normalize error */
-	err *= (frame_height * frame_width);
-	err /= (height * width);
-
-	if (err == 0)
-		return INT_MAX;
-
-	return err;
-}
-
-/* This function is rather CPU-intensive. It's better to use hardware
- * to detect movement direction when possible.
- */
-static void find_overlap(struct aes_stripe *first_frame,
-			 struct aes_stripe *second_frame,
-			 unsigned int *min_error,
-			 unsigned int frame_width,
-			 unsigned int frame_height)
-{
-	int dx, dy;
-	unsigned int err;
-	*min_error = INT_MAX;
-
-	/* Seeking in horizontal and vertical dimensions,
-	 * for horizontal dimension we'll check only 8 pixels
-	 * in both directions. For vertical direction diff is
-	 * rarely less than 2, so start with it.
-	 */
-	for (dy = 2; dy < frame_height; dy++) {
-		for (dx = -8; dx < 8; dx++) {
-			err = calc_error(first_frame, second_frame,
-				dx, dy, frame_width, frame_height);
-			if (err < *min_error) {
-				*min_error = err;
-				second_frame->delta_x = -dx;
-				second_frame->delta_y = dy;
-			}
-		}
-	}
-}
-
-unsigned int aes_calc_delta(GSList *stripes, size_t num_stripes,
-	unsigned int frame_width, unsigned int frame_height,
-	gboolean reverse)
-{
-	GSList *list_entry = stripes;
-	GTimer *timer;
-	int frame = 1;
-	int height = 0;
-	struct aes_stripe *prev_stripe = list_entry->data;
-	unsigned int min_error;
-
-	list_entry = g_slist_next(list_entry);
-
-	timer = g_timer_new();
-	do {
-		struct aes_stripe *cur_stripe = list_entry->data;
-
-		if (reverse) {
-			find_overlap(prev_stripe, cur_stripe, &min_error,
-				frame_width, frame_height);
-			prev_stripe->delta_y = -prev_stripe->delta_y;
-			prev_stripe->delta_x = -prev_stripe->delta_x;
-		}
-		else
-			find_overlap(cur_stripe, prev_stripe, &min_error,
-				frame_width, frame_height);
-
-		frame++;
-		height += prev_stripe->delta_y;
-		prev_stripe = cur_stripe;
-		list_entry = g_slist_next(list_entry);
-
-	} while (frame < num_stripes);
-
-	if (height < 0)
-		height = -height;
-	height += frame_height;
-	g_timer_stop(timer);
-	fp_dbg("calc delta completed in %f secs", g_timer_elapsed(timer, NULL));
-	g_timer_destroy(timer);
-
-	return height;
-}
-
-static inline void aes_blit_stripe(struct fp_img *img,
-				   struct aes_stripe *stripe,
-				   int x, int y, unsigned int frame_width,
-				   unsigned int frame_height)
-{
-	unsigned int ix, iy;
-	unsigned int fx, fy;
-	unsigned int width, height;
-
-	/* Find intersection */
-	if (x < 0) {
-		width = frame_width + x;
-		ix = 0;
-		fx = -x;
-	} else {
-		ix = x;
-		fx = 0;
-		width = frame_width;
-	}
-	if ((ix + width) > img->width)
-		width = img->width - ix;
-
-	if (y < 0) {
-		iy = 0;
-		fy = -y;
-		height = frame_height + y;
-	} else {
-		iy = y;
-		fy = 0;
-		height = frame_height;
-	}
-
-	if (fx > frame_width)
-		return;
-
-	if (fy > frame_height)
-		return;
-
-	if (ix > img->width)
-		return;
-
-	if (iy > img->height)
-		return;
-
-	if ((iy + height) > img->height)
-		height = img->height - iy;
-
-	for (; fy < height; fy++, iy++) {
-		if (x < 0) {
-			ix = 0;
-			fx = -x;
-		} else {
-			ix = x;
-			fx = 0;
-		}
-		for (; fx < width; fx++, ix++) {
-			img->data[ix + (iy * img->width)] = aes_get_pixel(stripe, fx, fy, frame_width, frame_height);
-		}
-	}
-}
-
-struct fp_img *aes_assemble(GSList *stripes, size_t stripes_len,
-			    unsigned int frame_width, unsigned int frame_height, unsigned int img_width)
-{
-	GSList *stripe;
-	struct fp_img *img;
-	int height = 0;
-	int i, y, x;
-	gboolean reverse = FALSE;
-	struct aes_stripe *aes_stripe;
-
-	BUG_ON(stripes_len == 0);
-	BUG_ON(img_width < frame_width);
-
-	/* Calculate height */
-	i = 0;
-	stripe = stripes;
-
-	/* No offset for 1st image */
-	aes_stripe = stripe->data;
-	aes_stripe->delta_x = 0;
-	aes_stripe->delta_y = 0;
-	do {
-		aes_stripe = stripe->data;
-
-		height += aes_stripe->delta_y;
-		i++;
-		stripe = g_slist_next(stripe);
-	} while (i < stripes_len);
-
-	fp_dbg("height is %d", height);
-
-	if (height < 0) {
-		reverse = TRUE;
-		height = -height;
-	}
-
-	/* For last frame */
-	height += frame_height;
-
-	/* Create buffer big enough for max image */
-	img = fpi_img_new(img_width * height);
-	img->flags = FP_IMG_COLORS_INVERTED;
-	img->width = img_width;
-	img->height = height;
-
-	/* Assemble stripes */
-	i = 0;
-	stripe = stripes;
-	y = reverse ? (height - frame_height) : 0;
-	x = (img_width - frame_width) / 2;
-
-	do {
-		aes_stripe = stripe->data;
-
-		y += aes_stripe->delta_y;
-		x += aes_stripe->delta_x;
-
-		aes_blit_stripe(img, aes_stripe, x, y, frame_width, frame_height);
-
-		stripe = g_slist_next(stripe);
-		i++;
-	} while (i < stripes_len);
-
-	return img;
-}
diff --git a/libfprint/aeslib.h b/libfprint/aeslib.h
index 7721d11..2dd6cea 100644
--- a/libfprint/aeslib.h
+++ b/libfprint/aeslib.h
@@ -27,11 +27,8 @@ struct aes_regwrite {
 	unsigned char value;
 };
 
-struct aes_stripe {
-	int delta_x;
-	int delta_y;
-	unsigned char data[0];
-};
+struct fpi_frame;
+struct fpi_frame_asmbl_ctx;
 
 typedef void (*aes_write_regv_cb)(struct fp_img_dev *dev, int result,
 	void *user_data);
@@ -39,12 +36,10 @@ typedef void (*aes_write_regv_cb)(struct fp_img_dev *dev, int result,
 void aes_write_regv(struct fp_img_dev *dev, const struct aes_regwrite *regs,
 	unsigned int num_regs, aes_write_regv_cb callback, void *user_data);
 
-unsigned int aes_calc_delta(GSList *stripes, size_t stripes_len,
-	unsigned int frame_width, unsigned int frame_height,
-	gboolean reverse);
-
-struct fp_img *aes_assemble(GSList *stripes, size_t stripes_len,
-	unsigned int frame_width, unsigned int frame_height, unsigned int img_width);
+unsigned char aes_get_pixel(struct fpi_frame_asmbl_ctx *ctx,
+			    struct fpi_frame *frame,
+			    unsigned int x,
+			    unsigned int y);
 
 #endif
 
diff --git a/libfprint/assembling.c b/libfprint/assembling.c
new file mode 100644
index 0000000..dd8d212
--- /dev/null
+++ b/libfprint/assembling.c
@@ -0,0 +1,277 @@
+/*
+ * Image assembling routines
+ * Copyright (C) 2007-2008 Daniel Drake <dsd@gentoo.org>
+ * Copyright (C) 2015 Vasily Khoruzhick <anarsoul@gmail.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#define FP_COMPONENT "assembling"
+
+#include <errno.h>
+#include <string.h>
+
+#include <libusb.h>
+#include <glib.h>
+
+#include "fp_internal.h"
+#include "assembling.h"
+
+static unsigned int calc_error(struct fpi_frame_asmbl_ctx *ctx,
+			       struct fpi_frame *first_frame,
+			       struct fpi_frame *second_frame,
+			       int dx,
+			       int dy)
+{
+	unsigned int width, height;
+	unsigned int x1, y1, x2, y2, err, i, j;
+
+	width = ctx->frame_width - (dx > 0 ? dx : -dx);
+	height = ctx->frame_height - dy;
+
+	y1 = 0;
+	y2 = dy;
+	i = 0;
+	err = 0;
+	do {
+		x1 = dx < 0 ? 0 : dx;
+		x2 = dx < 0 ? -dx : 0;
+		j = 0;
+
+		do {
+			unsigned char v1, v2;
+
+
+			v1 = ctx->get_pixel(ctx, first_frame, x1, y1);
+			v2 = ctx->get_pixel(ctx, second_frame, x2, y2);
+			err += v1 > v2 ? v1 - v2 : v2 - v1;
+			j++;
+			x1++;
+			x2++;
+
+		} while (j < width);
+		i++;
+		y1++;
+		y2++;
+	} while (i < height);
+
+	/* Normalize error */
+	err *= (ctx->frame_height * ctx->frame_width);
+	err /= (height * width);
+
+	if (err == 0)
+		return INT_MAX;
+
+	return err;
+}
+
+/* This function is rather CPU-intensive. It's better to use hardware
+ * to detect movement direction when possible.
+ */
+static void find_overlap(struct fpi_frame_asmbl_ctx *ctx,
+			 struct fpi_frame *first_frame,
+			 struct fpi_frame *second_frame,
+			 unsigned int *min_error)
+{
+	int dx, dy;
+	unsigned int err;
+	*min_error = INT_MAX;
+
+	/* Seeking in horizontal and vertical dimensions,
+	 * for horizontal dimension we'll check only 8 pixels
+	 * in both directions. For vertical direction diff is
+	 * rarely less than 2, so start with it.
+	 */
+	for (dy = 2; dy < ctx->frame_height; dy++) {
+		for (dx = -8; dx < 8; dx++) {
+			err = calc_error(ctx, first_frame, second_frame,
+				dx, dy);
+			if (err < *min_error) {
+				*min_error = err;
+				second_frame->delta_x = -dx;
+				second_frame->delta_y = dy;
+			}
+		}
+	}
+}
+
+unsigned int fpi_do_movement_estimation(struct fpi_frame_asmbl_ctx *ctx,
+			    GSList *stripes, size_t num_stripes,
+			    gboolean reverse)
+{
+	GSList *list_entry = stripes;
+	GTimer *timer;
+	int frame = 1;
+	int height = 0;
+	struct fpi_frame *prev_stripe = list_entry->data;
+	unsigned int min_error;
+
+	list_entry = g_slist_next(list_entry);
+
+	timer = g_timer_new();
+	do {
+		struct fpi_frame *cur_stripe = list_entry->data;
+
+		if (reverse) {
+			find_overlap(ctx, prev_stripe, cur_stripe, &min_error);
+			prev_stripe->delta_y = -prev_stripe->delta_y;
+			prev_stripe->delta_x = -prev_stripe->delta_x;
+		}
+		else
+			find_overlap(ctx, cur_stripe, prev_stripe, &min_error);
+
+		frame++;
+		height += prev_stripe->delta_y;
+		prev_stripe = cur_stripe;
+		list_entry = g_slist_next(list_entry);
+
+	} while (frame < num_stripes);
+
+	if (height < 0)
+		height = -height;
+	height += ctx->frame_height;
+	g_timer_stop(timer);
+	fp_dbg("calc delta completed in %f secs", g_timer_elapsed(timer, NULL));
+	g_timer_destroy(timer);
+
+	return height;
+}
+
+static inline void aes_blit_stripe(struct fpi_frame_asmbl_ctx *ctx,
+				   struct fp_img *img,
+				   struct fpi_frame *stripe,
+				   int x, int y)
+{
+	unsigned int ix, iy;
+	unsigned int fx, fy;
+	unsigned int width, height;
+
+	/* Find intersection */
+	if (x < 0) {
+		width = ctx->frame_width + x;
+		ix = 0;
+		fx = -x;
+	} else {
+		ix = x;
+		fx = 0;
+		width = ctx->frame_width;
+	}
+	if ((ix + width) > img->width)
+		width = img->width - ix;
+
+	if (y < 0) {
+		iy = 0;
+		fy = -y;
+		height = ctx->frame_height + y;
+	} else {
+		iy = y;
+		fy = 0;
+		height = ctx->frame_height;
+	}
+
+	if (fx > ctx->frame_width)
+		return;
+
+	if (fy > ctx->frame_height)
+		return;
+
+	if (ix > img->width)
+		return;
+
+	if (iy > img->height)
+		return;
+
+	if ((iy + height) > img->height)
+		height = img->height - iy;
+
+	for (; fy < height; fy++, iy++) {
+		if (x < 0) {
+			ix = 0;
+			fx = -x;
+		} else {
+			ix = x;
+			fx = 0;
+		}
+		for (; fx < width; fx++, ix++) {
+			img->data[ix + (iy * img->width)] = ctx->get_pixel(ctx, stripe, fx, fy);
+		}
+	}
+}
+
+struct fp_img *fpi_assemble_frames(struct fpi_frame_asmbl_ctx *ctx,
+			    GSList *stripes, size_t stripes_len)
+{
+	GSList *stripe;
+	struct fp_img *img;
+	int height = 0;
+	int i, y, x;
+	gboolean reverse = FALSE;
+	struct fpi_frame *fpi_frame;
+
+	BUG_ON(stripes_len == 0);
+	BUG_ON(ctx->image_width < ctx->frame_width);
+
+	/* Calculate height */
+	i = 0;
+	stripe = stripes;
+
+	/* No offset for 1st image */
+	fpi_frame = stripe->data;
+	fpi_frame->delta_x = 0;
+	fpi_frame->delta_y = 0;
+	do {
+		fpi_frame = stripe->data;
+
+		height += fpi_frame->delta_y;
+		i++;
+		stripe = g_slist_next(stripe);
+	} while (i < stripes_len);
+
+	fp_dbg("height is %d", height);
+
+	if (height < 0) {
+		reverse = TRUE;
+		height = -height;
+	}
+
+	/* For last frame */
+	height += ctx->frame_height;
+
+	/* Create buffer big enough for max image */
+	img = fpi_img_new(ctx->image_width * height);
+	img->flags = FP_IMG_COLORS_INVERTED;
+	img->width = ctx->image_width;
+	img->height = height;
+
+	/* Assemble stripes */
+	i = 0;
+	stripe = stripes;
+	y = reverse ? (height - ctx->frame_height) : 0;
+	x = (ctx->image_width - ctx->frame_width) / 2;
+
+	do {
+		fpi_frame = stripe->data;
+
+		y += fpi_frame->delta_y;
+		x += fpi_frame->delta_x;
+
+		aes_blit_stripe(ctx, img, fpi_frame, x, y);
+
+		stripe = g_slist_next(stripe);
+		i++;
+	} while (i < stripes_len);
+
+	return img;
+}
diff --git a/libfprint/assembling.h b/libfprint/assembling.h
new file mode 100644
index 0000000..1d1905d
--- /dev/null
+++ b/libfprint/assembling.h
@@ -0,0 +1,50 @@
+/*
+ * Image assembling routines
+ * Shared functions between libfprint Authentec drivers
+ * Copyright (C) 2007 Daniel Drake <dsd@gentoo.org>
+ * Copyright (C) 2015 Vasily Khoruzhick <anarsoul@gmail.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef __ASSEMBLING_H__
+#define __ASSEMBLING_H__
+
+#include <fp_internal.h>
+
+struct fpi_frame {
+	int delta_x;
+	int delta_y;
+	unsigned char data[0];
+};
+
+struct fpi_frame_asmbl_ctx {
+	unsigned frame_width;
+	unsigned frame_height;
+	unsigned image_width;
+	unsigned char (*get_pixel)(struct fpi_frame_asmbl_ctx *ctx,
+				   struct fpi_frame *frame,
+				   unsigned x,
+				   unsigned y);
+};
+
+unsigned int fpi_do_movement_estimation(struct fpi_frame_asmbl_ctx *ctx,
+			    GSList *stripes, size_t stripes_len,
+			    gboolean reverse);
+
+struct fp_img *fpi_assemble_frames(struct fpi_frame_asmbl_ctx *ctx,
+			    GSList *stripes, size_t stripes_len);
+
+#endif
diff --git a/libfprint/drivers/aes1610.c b/libfprint/drivers/aes1610.c
index f87a63c..d8aaeaa 100644
--- a/libfprint/drivers/aes1610.c
+++ b/libfprint/drivers/aes1610.c
@@ -30,6 +30,7 @@
 
 #include <libusb.h>
 
+#include <assembling.h>
 #include <aeslib.h>
 #include <fp_internal.h>
 
@@ -66,6 +67,7 @@ static int adjust_gain(unsigned char *buffer, int status);
 #define FRAME_WIDTH	128
 #define FRAME_HEIGHT	8
 #define FRAME_SIZE	(FRAME_WIDTH * FRAME_HEIGHT)
+#define IMAGE_WIDTH	(FRAME_WIDTH + (FRAME_WIDTH / 2))
 /* maximum number of frames to read during a scan */
 /* FIXME reduce substantially */
 #define MAX_FRAMES		350
@@ -80,6 +82,13 @@ struct aes1610_dev {
 	uint8_t blanks_count;
 };
 
+static struct fpi_frame_asmbl_ctx assembling_ctx = {
+	.frame_width = FRAME_WIDTH,
+	.frame_height = FRAME_HEIGHT,
+	.image_width = IMAGE_WIDTH,
+	.get_pixel = aes_get_pixel,
+};
+
 typedef void (*aes1610_read_regs_cb)(struct fp_img_dev *dev, int status,
 	unsigned char *regs, void *user_data);
 
@@ -580,7 +589,7 @@ static void capture_read_strip_cb(struct libusb_transfer *transfer)
 
 	if (sum > 0) {
 		/* FIXME: would preallocating strip buffers be a decent optimization? */
-		struct aes_stripe *stripe = g_malloc(FRAME_WIDTH * (FRAME_HEIGHT / 2) + sizeof(struct aes_stripe));
+		struct fpi_frame *stripe = g_malloc(FRAME_WIDTH * (FRAME_HEIGHT / 2) + sizeof(struct fpi_frame));
 		stripe->delta_x = 0;
 		stripe->delta_y = 0;
 		stripdata = stripe->data;
@@ -618,18 +627,14 @@ static void capture_read_strip_cb(struct libusb_transfer *transfer)
 		/* send stop capture bits */
 		aes_write_regv(dev, capture_stop, G_N_ELEMENTS(capture_stop), stub_capture_stop_cb, NULL);
 		aesdev->strips = g_slist_reverse(aesdev->strips);
-		height = aes_calc_delta(aesdev->strips, aesdev->strips_len,
-			FRAME_WIDTH, FRAME_HEIGHT, FALSE);
-		rev_height = aes_calc_delta(aesdev->strips, aesdev->strips_len,
-			FRAME_WIDTH, FRAME_HEIGHT, TRUE);
+		height = fpi_do_movement_estimation(&assembling_ctx, aesdev->strips, aesdev->strips_len, FALSE);
+		rev_height = fpi_do_movement_estimation(&assembling_ctx, aesdev->strips, aesdev->strips_len, TRUE);
 		fp_dbg("heights: %d rev: %d", height, rev_height);
 		if (rev_height < height) {
 			fp_dbg("Reversed direction");
-			height = aes_calc_delta(aesdev->strips, aesdev->strips_len,
-				FRAME_WIDTH, FRAME_HEIGHT, FALSE);
+			height = fpi_do_movement_estimation(&assembling_ctx, aesdev->strips, aesdev->strips_len, FALSE);
 		}
-		img = aes_assemble(aesdev->strips, aesdev->strips_len,
-			FRAME_WIDTH, FRAME_HEIGHT, FRAME_WIDTH + FRAME_WIDTH / 2);
+		img = fpi_assemble_frames(&assembling_ctx, aesdev->strips, aesdev->strips_len);
 		g_slist_free_full(aesdev->strips, g_free);
 		aesdev->strips = NULL;
 		aesdev->strips_len = 0;
@@ -843,7 +848,7 @@ struct fp_img_driver aes1610_driver = {
 	},
 	.flags = 0,
 	.img_height = -1,
-	.img_width = FRAME_WIDTH + FRAME_WIDTH / 2,
+	.img_width = IMAGE_WIDTH,
 
 	.bz3_threshold = 50,
 
diff --git a/libfprint/drivers/aes1660.c b/libfprint/drivers/aes1660.c
index b221561..8e63fe3 100644
--- a/libfprint/drivers/aes1660.c
+++ b/libfprint/drivers/aes1660.c
@@ -28,12 +28,22 @@
 
 #include <fp_internal.h>
 
+#include <assembling.h>
+#include <aeslib.h>
+
 #include "aesx660.h"
 #include "aes1660.h"
 #include "driver_ids.h"
 
 #define FRAME_WIDTH 128
-#define SCALE_FACTOR 2
+#define IMAGE_WIDTH	(FRAME_WIDTH + (FRAME_WIDTH / 2))
+
+static struct fpi_frame_asmbl_ctx assembling_ctx = {
+	.frame_width = FRAME_WIDTH,
+	.frame_height = AESX660_FRAME_HEIGHT,
+	.image_width = IMAGE_WIDTH,
+	.get_pixel = aes_get_pixel,
+};
 
 static int dev_init(struct fp_img_dev *dev, unsigned long driver_data)
 {
@@ -55,7 +65,7 @@ static int dev_init(struct fp_img_dev *dev, unsigned long driver_data)
 	aesdev->init_seqs_len[1] = array_n_elements(aes1660_init_2);
 	aesdev->start_imaging_cmd = (unsigned char *)aes1660_start_imaging_cmd;
 	aesdev->start_imaging_cmd_len = sizeof(aes1660_start_imaging_cmd);
-	aesdev->frame_width = FRAME_WIDTH;
+	aesdev->assembling_ctx = &assembling_ctx;
 	aesdev->extra_img_flags = FP_IMG_PARTIAL;
 
 	fpi_imgdev_open_complete(dev, 0);
diff --git a/libfprint/drivers/aes2501.c b/libfprint/drivers/aes2501.c
index 264e2dc..426bd9e 100644
--- a/libfprint/drivers/aes2501.c
+++ b/libfprint/drivers/aes2501.c
@@ -28,6 +28,7 @@
 
 #include <libusb.h>
 
+#include <assembling.h>
 #include <aeslib.h>
 #include <fp_internal.h>
 
@@ -58,6 +59,7 @@ static void complete_deactivation(struct fp_img_dev *dev);
 #define FRAME_WIDTH		192
 #define FRAME_HEIGHT	16
 #define FRAME_SIZE		(FRAME_WIDTH * FRAME_HEIGHT)
+#define IMAGE_WIDTH		(FRAME_WIDTH + (FRAME_WIDTH / 2))
 /* maximum number of frames to read during a scan */
 /* FIXME reduce substantially */
 #define MAX_FRAMES		150
@@ -72,6 +74,13 @@ struct aes2501_dev {
 	int no_finger_cnt;
 };
 
+static struct fpi_frame_asmbl_ctx assembling_ctx = {
+	.frame_width = FRAME_WIDTH,
+	.frame_height = FRAME_HEIGHT,
+	.image_width = IMAGE_WIDTH,
+	.get_pixel = aes_get_pixel,
+};
+
 typedef void (*aes2501_read_regs_cb)(struct fp_img_dev *dev, int status,
 	unsigned char *regs, void *user_data);
 
@@ -484,18 +493,18 @@ static void capture_read_strip_cb(struct libusb_transfer *transfer)
 			unsigned int height, rev_height;
 
 			aesdev->strips = g_slist_reverse(aesdev->strips);
-			height = aes_calc_delta(aesdev->strips, aesdev->strips_len,
-				FRAME_WIDTH, FRAME_HEIGHT, FALSE);
-			rev_height = aes_calc_delta(aesdev->strips, aesdev->strips_len,
-				FRAME_WIDTH, FRAME_HEIGHT, TRUE);
+			height = fpi_do_movement_estimation(&assembling_ctx,
+					aesdev->strips, aesdev->strips_len, FALSE);
+			rev_height = fpi_do_movement_estimation(&assembling_ctx,
+					aesdev->strips, aesdev->strips_len, TRUE);
 			fp_dbg("heights: %d rev: %d", height, rev_height);
 			if (rev_height < height) {
 				fp_dbg("Reversed direction");
-				height = aes_calc_delta(aesdev->strips, aesdev->strips_len,
-					FRAME_WIDTH, FRAME_HEIGHT, FALSE);
+				height = fpi_do_movement_estimation(&assembling_ctx,
+						aesdev->strips, aesdev->strips_len, FALSE);
 			}
-			img = aes_assemble(aesdev->strips, aesdev->strips_len,
-				FRAME_WIDTH, FRAME_HEIGHT, FRAME_WIDTH + FRAME_WIDTH / 2);
+			img = fpi_assemble_frames(&assembling_ctx,
+						  aesdev->strips, aesdev->strips_len);
 			g_slist_free_full(aesdev->strips, g_free);
 			aesdev->strips = NULL;
 			aesdev->strips_len = 0;
@@ -509,7 +518,7 @@ static void capture_read_strip_cb(struct libusb_transfer *transfer)
 	} else {
 		/* obtain next strip */
 		/* FIXME: would preallocating strip buffers be a decent optimization? */
-		struct aes_stripe *stripe = g_malloc(FRAME_WIDTH * FRAME_HEIGHT / 2 + sizeof(struct aes_stripe));
+		struct fpi_frame *stripe = g_malloc(FRAME_WIDTH * FRAME_HEIGHT / 2 + sizeof(struct fpi_frame));
 		stripe->delta_x = 0;
 		stripe->delta_y = 0;
 		stripdata = stripe->data;
@@ -881,7 +890,7 @@ struct fp_img_driver aes2501_driver = {
 	},
 	.flags = 0,
 	.img_height = -1,
-	.img_width = FRAME_WIDTH + FRAME_WIDTH / 2,
+	.img_width = IMAGE_WIDTH,
 
 	.open = dev_init,
 	.close = dev_deinit,
diff --git a/libfprint/drivers/aes2550.c b/libfprint/drivers/aes2550.c
index 29e59d1..822dbcd 100644
--- a/libfprint/drivers/aes2550.c
+++ b/libfprint/drivers/aes2550.c
@@ -28,6 +28,7 @@
 
 #include <libusb.h>
 
+#include <assembling.h>
 #include <aeslib.h>
 #include <fp_internal.h>
 
@@ -56,6 +57,7 @@ static void complete_deactivation(struct fp_img_dev *dev);
 #define FRAME_WIDTH		192
 #define FRAME_HEIGHT		8
 #define FRAME_SIZE		(FRAME_WIDTH * FRAME_HEIGHT)
+#define IMAGE_WIDTH		(FRAME_WIDTH + (FRAME_WIDTH / 2))
 
 struct aes2550_dev {
 	GSList *strips;
@@ -64,6 +66,13 @@ struct aes2550_dev {
 	int heartbeat_cnt;
 };
 
+static struct fpi_frame_asmbl_ctx assembling_ctx = {
+	.frame_width = FRAME_WIDTH,
+	.frame_height = FRAME_HEIGHT,
+	.image_width = IMAGE_WIDTH,
+	.get_pixel = aes_get_pixel,
+};
+
 /****** FINGER PRESENCE DETECTION ******/
 
 static unsigned char finger_det_reqs[] = {
@@ -204,7 +213,7 @@ static int process_strip_data(struct fpi_ssm *ssm, unsigned char *data)
 	unsigned char *stripdata;
 	struct fp_img_dev *dev = ssm->priv;
 	struct aes2550_dev *aesdev = dev->priv;
-	struct aes_stripe *stripe;
+	struct fpi_frame *stripe;
 	int len;
 
 	if (data[0] != AES2550_EDATA_MAGIC) {
@@ -215,7 +224,7 @@ static int process_strip_data(struct fpi_ssm *ssm, unsigned char *data)
 	if (len != (AES2550_STRIP_SIZE - 3)) {
 		fp_dbg("Bogus frame len: %.4x\n", len);
 	}
-	stripe = g_malloc(FRAME_WIDTH * FRAME_HEIGHT / 2 + sizeof(struct aes_stripe)); /* 4 bits per pixel */
+	stripe = g_malloc(FRAME_WIDTH * FRAME_HEIGHT / 2 + sizeof(struct fpi_frame)); /* 4 bits per pixel */
 	stripe->delta_x = (int8_t)data[6];
 	stripe->delta_y = -(int8_t)data[7];
 	stripdata = stripe->data;
@@ -253,8 +262,8 @@ static void capture_set_idle_reqs_cb(struct libusb_transfer *transfer)
 		struct fp_img *img;
 
 		aesdev->strips = g_slist_reverse(aesdev->strips);
-		img = aes_assemble(aesdev->strips, aesdev->strips_len,
-			FRAME_WIDTH, FRAME_HEIGHT, FRAME_WIDTH + FRAME_WIDTH / 2);
+		img = fpi_assemble_frames(&assembling_ctx,
+					  aesdev->strips, aesdev->strips_len);
 		g_slist_free_full(aesdev->strips, g_free);
 		aesdev->strips = NULL;
 		aesdev->strips_len = 0;
diff --git a/libfprint/drivers/aes2660.c b/libfprint/drivers/aes2660.c
index d7b6cef..2edb765 100644
--- a/libfprint/drivers/aes2660.c
+++ b/libfprint/drivers/aes2660.c
@@ -28,11 +28,22 @@
 
 #include <fp_internal.h>
 
+#include <assembling.h>
+#include <aeslib.h>
+
 #include "aesx660.h"
 #include "aes2660.h"
 #include "driver_ids.h"
 
 #define FRAME_WIDTH 192
+#define IMAGE_WIDTH	(FRAME_WIDTH + (FRAME_WIDTH / 2))
+
+static struct fpi_frame_asmbl_ctx assembling_ctx = {
+	.frame_width = FRAME_WIDTH,
+	.frame_height = AESX660_FRAME_HEIGHT,
+	.image_width = IMAGE_WIDTH,
+	.get_pixel = aes_get_pixel,
+};
 
 static int dev_init(struct fp_img_dev *dev, unsigned long driver_data)
 {
@@ -55,7 +66,7 @@ static int dev_init(struct fp_img_dev *dev, unsigned long driver_data)
 	aesdev->init_seqs_len[1] = array_n_elements(aes2660_init_2);
 	aesdev->start_imaging_cmd = (unsigned char *)aes2660_start_imaging_cmd;
 	aesdev->start_imaging_cmd_len = sizeof(aes2660_start_imaging_cmd);
-	aesdev->frame_width = FRAME_WIDTH;
+	aesdev->assembling_ctx = &assembling_ctx;
 
 	fpi_imgdev_open_complete(dev, 0);
 	return 0;
diff --git a/libfprint/drivers/aesx660.c b/libfprint/drivers/aesx660.c
index 433ba33..278fe81 100644
--- a/libfprint/drivers/aesx660.c
+++ b/libfprint/drivers/aesx660.c
@@ -30,6 +30,7 @@
 
 #include <libusb.h>
 
+#include <assembling.h>
 #include <aeslib.h>
 #include <fp_internal.h>
 
@@ -41,7 +42,7 @@ static void complete_deactivation(struct fp_img_dev *dev);
 #define EP_IN			(1 | LIBUSB_ENDPOINT_IN)
 #define EP_OUT			(2 | LIBUSB_ENDPOINT_OUT)
 #define BULK_TIMEOUT		4000
-#define FRAME_HEIGHT		8
+#define FRAME_HEIGHT		AESX660_FRAME_HEIGHT
 
 #define min(a, b) (((a) < (b)) ? (a) : (b))
 
@@ -273,12 +274,12 @@ enum capture_states {
 /* Returns number of processed bytes */
 static int process_stripe_data(struct fpi_ssm *ssm, unsigned char *data)
 {
-	struct aes_stripe *stripe;
+	struct fpi_frame *stripe;
 	unsigned char *stripdata;
 	struct fp_img_dev *dev = ssm->priv;
 	struct aesX660_dev *aesdev = dev->priv;
 
-	stripe = g_malloc(aesdev->frame_width * FRAME_HEIGHT / 2 + sizeof(struct aes_stripe)); /* 4 bpp */
+	stripe = g_malloc(aesdev->assembling_ctx->frame_width * FRAME_HEIGHT / 2 + sizeof(struct fpi_frame)); /* 4 bpp */
 	stripdata = stripe->data;
 
 	fp_dbg("Processing frame %.2x %.2x", data[AESX660_IMAGE_OK_OFFSET],
@@ -289,7 +290,7 @@ static int process_stripe_data(struct fpi_ssm *ssm, unsigned char *data)
 	fp_dbg("Offset to previous frame: %d %d", stripe->delta_x, stripe->delta_y);
 
 	if (data[AESX660_IMAGE_OK_OFFSET] == AESX660_IMAGE_OK) {
-		memcpy(stripdata, data + AESX660_IMAGE_OFFSET, aesdev->frame_width * FRAME_HEIGHT / 2);
+		memcpy(stripdata, data + AESX660_IMAGE_OFFSET, aesdev->assembling_ctx->frame_width * FRAME_HEIGHT / 2);
 
 		aesdev->strips = g_slist_prepend(aesdev->strips, stripe);
 		aesdev->strips_len++;
@@ -311,8 +312,7 @@ static void capture_set_idle_cmd_cb(struct libusb_transfer *transfer)
 		struct fp_img *img;
 
 		aesdev->strips = g_slist_reverse(aesdev->strips);
-		img = aes_assemble(aesdev->strips, aesdev->strips_len,
-			aesdev->frame_width, FRAME_HEIGHT, aesdev->frame_width + aesdev->frame_width / 2);
+		img = fpi_assemble_frames(aesdev->assembling_ctx, aesdev->strips, aesdev->strips_len);
 		img->flags |= aesdev->extra_img_flags;
 		g_slist_foreach(aesdev->strips, (GFunc) g_free, NULL);
 		g_slist_free(aesdev->strips);
diff --git a/libfprint/drivers/aesx660.h b/libfprint/drivers/aesx660.h
index 044d809..2106ca2 100644
--- a/libfprint/drivers/aesx660.h
+++ b/libfprint/drivers/aesx660.h
@@ -41,6 +41,8 @@
 #define AESX660_IMAGE_OFFSET 43
 #define AESX660_BULK_TRANSFER_SIZE 4096
 
+#define AESX660_FRAME_HEIGHT 8
+
 struct aesX660_dev {
 	GSList *strips;
 	size_t strips_len;
@@ -55,12 +57,11 @@ struct aesX660_dev {
 	size_t buffer_max;
 
 	/* Device-specific stuff */
-	int h_scale_factor;
 	struct aesX660_cmd *init_seqs[2];
 	size_t init_seqs_len[2];
 	unsigned char *start_imaging_cmd;
 	size_t start_imaging_cmd_len;
-	unsigned int frame_width;
+	struct fpi_frame_asmbl_ctx *assembling_ctx;
 	uint16_t extra_img_flags;
 };