diff --git a/backend/escl/escl.c b/backend/escl/escl.c
index 3c89f8009..4b8af2e6f 100644
--- a/backend/escl/escl.c
+++ b/backend/escl/escl.c
@@ -647,22 +647,23 @@ sane_start(SANE_Handle h)
     if (status != SANE_STATUS_GOOD)
         return (status);
     status = escl_scan(handler->scanner, handler->name, handler->result);
+    if (status != SANE_STATUS_GOOD)
+        return (status);
     fprintf(stderr, "DIM : [%s]\n", handler->scanner->default_format);
     if (!strncmp(handler->scanner->default_format, "image/jpeg", 10))
     {
-       get_JPEG_dimension(handler->scanner->tmp, &w, &he, &bps);
-    fprintf(stderr, "JPEG DIM : [%s]\n", handler->scanner->default_format);
+       status = get_JPEG_data(handler->scanner, &w, &he, &bps);
+       fprintf(stderr, "JPEG DIM : [%s]\n", handler->scanner->default_format);
     }
     else
     {
-      get_PNG_dimension(handler->scanner->tmp, &w, &he, &bps);
-    fprintf(stderr, "PNG DIM : [%s]\n", handler->scanner->default_format);
+       status = get_PNG_data(handler->scanner->tmp, &w, &he, &bps);
+       fprintf(stderr, "PNG DIM : [%s]\n", handler->scanner->default_format);
     }
+    if (status != SANE_STATUS_GOOD)
+        return (status);
     fprintf(stderr, "SIZE [%dx%dx%d]\n", w, he, bps);
-    if (bps == 0)
-	    return SANE_STATUS_INVAL;
     fprintf(stderr, "2-SIZE [%dx%dx%d]\n", w, he, bps);
-    fseek(handler->scanner->tmp, SEEK_SET, 0);
     handler->ps.depth = 8;
     handler->ps.pixels_per_line = w;
     handler->ps.lines = he;
@@ -728,17 +729,7 @@ sane_read(SANE_Handle h, SANE_Byte *buf, SANE_Int maxlen, SANE_Int *len)
     if (!handler->write_scan_data)
         handler->write_scan_data = SANE_TRUE;
     if (!handler->decompress_scan_data) {
-        if (handler->scanner->tmp == NULL)
-            return (SANE_STATUS_INVAL);
 	fprintf(stderr, "READ : [%s]\n", handler->scanner->default_format);
-        if (!strncmp(handler->scanner->default_format, "image/jpeg", 10)){
-	fprintf(stderr, "JPEG READ : [%s]\n", handler->scanner->default_format);
-	    status = get_JPEG_data(handler->scanner);
-	}
-        else{
-	fprintf(stderr, "PNG READ : [%s]\n", handler->scanner->default_format);
-            status = get_PNG_data(handler->scanner);
-	}
         if (status != SANE_STATUS_GOOD)
             return (status);
         handler->decompress_scan_data = SANE_TRUE;
diff --git a/backend/escl/escl.h b/backend/escl/escl.h
index a655d7955..b590f9c06 100644
--- a/backend/escl/escl.h
+++ b/backend/escl/escl.h
@@ -153,11 +153,9 @@ SANE_Status escl_scan(capabilities_t *scanner, SANE_String_Const name, char *res
 void escl_scanner(SANE_String_Const name, char *result);
 
 // JPEG
-void get_JPEG_dimension(FILE *fp, int *w, int *h, int *bps);
-SANE_Status get_JPEG_data(capabilities_t *scanner);
+SANE_Status get_JPEG_data(capabilities_t *scanner, int *w, int *h, int *bps);
 
 // PNG
-void get_PNG_dimension(FILE *fp, int *w, int *h, int *bps);
-SANE_Status get_PNG_data(capabilities_t *scanner);
+SANE_Status get_PNG_data(capabilities_t *scanner, int *w, int *h, int *bps);
 
 #endif
diff --git a/backend/escl/escl_jpeg.c b/backend/escl/escl_jpeg.c
index 38ac41c40..d3cc0244b 100644
--- a/backend/escl/escl_jpeg.c
+++ b/backend/escl/escl_jpeg.c
@@ -35,37 +35,6 @@ error_exit(j_common_ptr cinfo)
     longjmp(cinfo->client_data, 1);
 }
 
-/**
- * \fn static void get_JPEG_dimension(FILE *fp, int *w, int *h)
- * \brief Function that aims to get the dimensions of the jpeg image wich will be scanned.
- *        This function is called in the "sane_start" function.
- */
-void
-get_JPEG_dimension(FILE *fp, int *w, int *h, int *bps)
-{
-    struct jpeg_decompress_struct cinfo;
-    struct jpeg_error_mgr jerr;
-    jmp_buf env;
-
-    cinfo.err = jpeg_std_error(&jerr);
-    jerr.error_exit = error_exit;
-    cinfo.client_data = env;
-    if (setjmp(env))
-        return;
-    jpeg_create_decompress(&cinfo);
-    jpeg_stdio_src(&cinfo, fp);
-    jpeg_read_header(&cinfo, TRUE);
-    cinfo.out_color_space = JCS_RGB;
-    jpeg_start_decompress(&cinfo);
-    *w = cinfo.output_width;
-    *h = cinfo.output_height;
-    *bps = 3;
-    jpeg_finish_decompress(&cinfo);
-    jpeg_destroy_decompress(&cinfo);
-    fseek(fp, SEEK_SET, 0);
-}
-
-
 /**
  * \fn static boolean fill_input_buffer(j_decompress_ptr cinfo)
  * \brief Called in the "skip_input_data" function.
@@ -166,7 +135,7 @@ output_no_message(j_common_ptr __sane_unused__ cinfo)
  * \return SANE_STATUS_GOOD (if everything is OK, otherwise, SANE_STATUS_NO_MEM/SANE_STATUS_INVAL)
  */
 SANE_Status
-get_JPEG_data(capabilities_t *scanner)
+get_JPEG_data(capabilities_t *scanner, int *w, int *h, int *bps)
 {
     int start = 0;
     struct jpeg_decompress_struct cinfo;
@@ -209,6 +178,9 @@ get_JPEG_data(capabilities_t *scanner)
     scanner->img_data = surface;
     scanner->img_size = lineSize * cinfo.output_height;
     scanner->img_read = 0;
+    *w = cinfo.output_width;
+    *h = cinfo.output_height;
+    *bps = cinfo.output_components;
     jpeg_finish_decompress(&cinfo);
     jpeg_destroy_decompress(&cinfo);
     fclose(scanner->tmp);
@@ -217,14 +189,11 @@ get_JPEG_data(capabilities_t *scanner)
 }
 #else
 
-void
-get_JPEG_dimension(FILE  __sane_unused__ *fp, int  __sane_unused__ *w,
-                   int  __sane_unused__ *h, int  __sane_unused__ *bps)
-{
-}
-
 SANE_Status
-get_JPEG_data(capabilities_t  __sane_unused__ *scanner)
+get_JPEG_data(capabilities_t __sane_unused__ *scanner,
+              int __sane_unused__ *w,
+              int __sane_unused__ *h,
+              int __sane_unused__ *bps)
 {
 }
 
diff --git a/backend/escl/escl_png.c b/backend/escl/escl_png.c
index 7964911c3..797c58633 100644
--- a/backend/escl/escl_png.c
+++ b/backend/escl/escl_png.c
@@ -15,91 +15,6 @@
 
 #if(defined HAVE_LIBPNG)
 
-/**
- * \fn static void get_PNG_dimension(FILE *fp, int *w, int *h)
- * \brief Function that aims to get the dimensions of the png image wich will be scanned.
- *        This function is called in the "sane_start" function.
- */
-void
-get_PNG_dimension(FILE *fp, int *w, int *h, int *bps)
-{
-        unsigned int width, height;
-	png_byte magic[8];
-	fread (magic, 1, sizeof (magic), fp);
-	/* check for valid magic number */
-	if (!png_check_sig (magic, sizeof (magic)))
-	{
-		fprintf (stderr, "error: is not a valid PNG image!\n");
-		return;
-	}
-	/* create a png read struct */
-	png_structp png_ptr = png_create_read_struct
-		(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
-	if (!png_ptr)
-	{
-		return;
-	}
-	/* create a png info struct */
-	png_infop info_ptr = png_create_info_struct (png_ptr);
-	if (!info_ptr)
-	{
-		png_destroy_read_struct (&png_ptr, NULL, NULL);
-		return;
-	}
-	/* initialize the setjmp for returning properly after a libpng
-	   error occured */
-	if (setjmp (png_jmpbuf (png_ptr)))
-	{
-		png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
-		return;
-	}
-	/* setup libpng for using standard C fread() function
-	   with our FILE pointer */
-	png_init_io (png_ptr, fp);
-	/* tell libpng that we have already read the magic number */
-	png_set_sig_bytes (png_ptr, sizeof (magic));
-
-	/* read png info */
-	png_read_info (png_ptr, info_ptr);
-
-	int bit_depth, color_type;
-	/* get some usefull information from header */
-	bit_depth = png_get_bit_depth (png_ptr, info_ptr);
-	color_type = png_get_color_type (png_ptr, info_ptr);
-	/* convert index color images to RGB images */
-	if (color_type == PNG_COLOR_TYPE_PALETTE)
-		png_set_palette_to_rgb (png_ptr);
-	else if (color_type != PNG_COLOR_TYPE_RGB && color_type != PNG_COLOR_TYPE_RGB_ALPHA)
-	{
-		fprintf(stderr, "Format non pris en charge.\n");
-		return;
-	}
-        if (color_type ==  PNG_COLOR_TYPE_RGB_ALPHA)
-            *bps = 4;
-        else
-	    *bps = 3;
-	if (png_get_valid (png_ptr, info_ptr, PNG_INFO_tRNS))
-		png_set_tRNS_to_alpha (png_ptr);
-	if (bit_depth == 16)
-		png_set_strip_16 (png_ptr);
-	else if (bit_depth < 8)
-		png_set_packing (png_ptr);
-	/* update info structure to apply transformations */
-	png_read_update_info (png_ptr, info_ptr);
-	/* retrieve updated information */
-	png_get_IHDR (png_ptr, info_ptr,
-			(png_uint_32*)(&width),
-			(png_uint_32*)(&height),
-			&bit_depth, &color_type,
-			NULL, NULL, NULL);
-        *w = (int)width;
-        *h = (int)height;
-	/* finish decompression and release memory */
-	png_read_end (png_ptr, NULL);
-	png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
-        fseek(fp, SEEK_SET, 0);
-}
-
 /**
  * \fn SANE_Status escl_sane_decompressor(escl_sane_t *handler)
  * \brief Function that aims to decompress the png image to SANE be able to read the image.
@@ -108,7 +23,7 @@ get_PNG_dimension(FILE *fp, int *w, int *h, int *bps)
  * \return SANE_STATUS_GOOD (if everything is OK, otherwise, SANE_STATUS_NO_MEM/SANE_STATUS_INVAL)
  */
 SANE_Status
-get_PNG_data(capabilities_t *scanner)
+get_PNG_data(capabilities_t *scanner, int *w, int *h, int *components)
 {
 	unsigned int  width = 0;           /* largeur */
 	unsigned int  height = 0;          /* hauteur */
@@ -170,9 +85,9 @@ get_PNG_data(capabilities_t *scanner)
         fprintf(stderr,"PNG format not supported.\n");
 		return (SANE_STATUS_INVAL);
 	}
-        if (color_type ==  PNG_COLOR_TYPE_RGB_ALPHA)
-            bps = 4;
-        else
+    if (color_type ==  PNG_COLOR_TYPE_RGB_ALPHA)
+        bps = 4;
+    else
 	    bps = 3;
 	if (png_get_valid (png_ptr, info_ptr, PNG_INFO_tRNS))
 		png_set_tRNS_to_alpha (png_ptr);
@@ -188,6 +103,10 @@ get_PNG_data(capabilities_t *scanner)
 			(png_uint_32*)(&height),
 			&bit_depth, &color_type,
 			NULL, NULL, NULL);
+
+    *w = (int)width;
+    *h = (int)height;
+    *components = bps;
 	// we can now allocate memory for storing pixel data
 	texels = (unsigned char *)malloc (sizeof (unsigned char) * width
 			* height * bps);
@@ -203,23 +122,20 @@ get_PNG_data(capabilities_t *scanner)
 	png_read_image (png_ptr, row_pointers);
 	// we don't need row pointers anymore
 	scanner->img_data = texels;
-        scanner->img_size = (int)(width * height * bps);
-        scanner->img_read = 0;
+    scanner->img_size = (int)(width * height * bps);
+    scanner->img_read = 0;
 	free (row_pointers);
-        fclose(scanner->tmp);
-        scanner->tmp = NULL;
-        return (SANE_STATUS_GOOD);
+    fclose(scanner->tmp);
+    scanner->tmp = NULL;
+    return (SANE_STATUS_GOOD);
 }
 #else
 
-void
-get_PNG_dimension(FILE __sane_unused__ *fp, int __sane_unused__ *w,
-                  int __sane_unused__ *h, int __sane_unused__ *bps)
-{
-}
-
 SANE_Status
-get_PNG_data(capabilities_t __sane_unused__ *scanner)
+get_PNG_data(capabilities_t __sane_unused__ *scanner,
+              int __sane_unused__ *w,
+              int __sane_unused__ *h,
+              int __sane_unused__ *bps)
 {
 }