diff --git a/libfprint/drivers/secugen/secugen.c b/libfprint/drivers/secugen/secugen.c
index 32668e57..b98a6ae8 100644
--- a/libfprint/drivers/secugen/secugen.c
+++ b/libfprint/drivers/secugen/secugen.c
@@ -1218,15 +1218,25 @@ capture_bulk_cb (FpiUsbTransfer *transfer,
                  gpointer        user_data,
                  GError         *error)
 {
+  FpiDeviceSecugen *self = FPI_DEVICE_SECUGEN (dev);
+
   if (error)
     {
       fpi_ssm_mark_failed (transfer->ssm, error);
       return;
     }
 
-  fpi_ssm_set_data (transfer->ssm,
-                    fpi_usb_transfer_ref (transfer),
-                    (GDestroyNotify) fpi_usb_transfer_unref);
+  if ((gsize) transfer->actual_length < SECUGEN_RAW_SIZE)
+    {
+      fp_warn ("Short image data: got %lu, expected %d",
+               (unsigned long) transfer->actual_length, SECUGEN_RAW_SIZE);
+      fpi_ssm_mark_failed (transfer->ssm,
+                           fpi_device_error_new (FP_DEVICE_ERROR_PROTO));
+      return;
+    }
+
+  memcpy (self->bulk_buffer, transfer->buffer,
+          MIN ((gsize) transfer->actual_length, (gsize) SECUGEN_BULK_BUF_SIZE));
   fpi_ssm_next_state (transfer->ssm);
 }
 
@@ -1282,28 +1292,17 @@ capture_run_state (FpiSsm *ssm, FpDevice *_dev)
 
     case CAPTURE_DONE:
       {
-        FpiUsbTransfer *img_transfer = fpi_ssm_get_data (ssm);
         FpImage *img;
         guint8 *raw;
         int i;
 
-        if (!img_transfer || img_transfer->actual_length < SECUGEN_RAW_SIZE)
-          {
-            fp_warn ("Short image data: got %ld, expected %d",
-                     img_transfer ? (long) img_transfer->actual_length : 0,
-                     SECUGEN_RAW_SIZE);
-            fpi_ssm_mark_failed (ssm,
-                                 fpi_device_error_new (FP_DEVICE_ERROR_PROTO));
-            return;
-          }
-
         img = fp_image_new (SECUGEN_IMG_WIDTH, SECUGEN_IMG_HEIGHT);
         img->ppmm = SECUGEN_PPMM;
         img->flags = FPI_IMAGE_V_FLIPPED | FPI_IMAGE_H_FLIPPED;
 
         /* Work on a copy of the raw 956x688 sensor data */
         raw = g_malloc (SECUGEN_RAW_SIZE);
-        memcpy (raw, img_transfer->buffer, SECUGEN_RAW_SIZE);
+        memcpy (raw, self->bulk_buffer, SECUGEN_RAW_SIZE);
 
         /*
          * SDK-matching image processing pipeline:
@@ -1428,15 +1427,16 @@ detect_bulk_cb (FpiUsbTransfer *transfer,
                 gpointer        user_data,
                 GError         *error)
 {
+  FpiDeviceSecugen *self = FPI_DEVICE_SECUGEN (dev);
+
   if (error)
     {
       fpi_ssm_mark_failed (transfer->ssm, error);
       return;
     }
 
-  fpi_ssm_set_data (transfer->ssm,
-                     fpi_usb_transfer_ref (transfer),
-                     (GDestroyNotify) fpi_usb_transfer_unref);
+  memcpy (self->bulk_buffer, transfer->buffer,
+          MIN ((gsize) transfer->actual_length, (gsize) SECUGEN_BULK_BUF_SIZE));
   fpi_ssm_next_state (transfer->ssm);
 }
 
@@ -1482,7 +1482,6 @@ detect_run_state (FpiSsm *ssm, FpDevice *_dev)
 
     case DETECT_ANALYZE:
       {
-        FpiUsbTransfer *img_transfer = fpi_ssm_get_data (ssm);
         guint64 sum = 0;
         /* Use central 50% of the 956x688 raw sensor area */
         int start_row = SECUGEN_RAW_HEIGHT / 4;
@@ -1499,10 +1498,9 @@ detect_run_state (FpiSsm *ssm, FpDevice *_dev)
             {
               int idx = y * SECUGEN_RAW_WIDTH + x;
 
-              if (idx < (int) img_transfer->actual_length &&
-                  idx < SECUGEN_BULK_BUF_SIZE)
+              if (idx < SECUGEN_BULK_BUF_SIZE)
                 {
-                  int val = (int) img_transfer->buffer[idx] -
+                  int val = (int) self->bulk_buffer[idx] -
                             (int) self->cal_raw[idx];
 
                   if (val < 0)
@@ -1529,9 +1527,8 @@ detect_run_state (FpiSsm *ssm, FpDevice *_dev)
              * the reference with partial finger touches.
              */
             if (mean <= 5)
-              memcpy (self->cal_raw, img_transfer->buffer,
-                      MIN ((gsize) img_transfer->actual_length,
-                           (gsize) SECUGEN_BULK_BUF_SIZE));
+              memcpy (self->cal_raw, self->bulk_buffer,
+                      SECUGEN_BULK_BUF_SIZE);
 
             /* Schedule another poll */
             self->finger_poll_source =
@@ -1645,6 +1642,7 @@ dev_init (FpImageDevice *dev)
 
     /* Allocate buffers */
     self->cal_raw = g_malloc0 (SECUGEN_BULK_BUF_SIZE);
+    self->bulk_buffer = g_malloc0 (SECUGEN_BULK_BUF_SIZE);
     self->fw_data = g_malloc0 (SECUGEN_FW_DATA_SIZE);
     self->fw_data_len = 0;
     self->ref_image = NULL;
@@ -1664,6 +1662,7 @@ dev_deinit (FpImageDevice *dev)
   GError *error = NULL;
 
   g_clear_pointer (&self->cal_raw, g_free);
+  g_clear_pointer (&self->bulk_buffer, g_free);
   g_clear_pointer (&self->fw_data, g_free);
   g_clear_pointer (&self->ref_image, g_free);
   self->has_ref_image = FALSE;
diff --git a/libfprint/drivers/secugen/secugen.h b/libfprint/drivers/secugen/secugen.h
index 569a6a02..d91ec8a9 100644
--- a/libfprint/drivers/secugen/secugen.h
+++ b/libfprint/drivers/secugen/secugen.h
@@ -137,6 +137,9 @@ struct _FpiDeviceSecugen
   guint8        sharpen_limit;     /* Overall scaling factor (/10) */
   gboolean      sharpen_enabled;   /* Whether post-resize sharpening is active */
 
+  /* Bulk read buffer for capture/detect frames */
+  guint8       *bulk_buffer;       /* Reusable buffer for 657KB bulk reads */
+
   /* Capture state */
   guint16       exposure;          /* Current exposure value */