Remove histogram stretching for negative images.

backend/mustek_usb2.c

@@ -122,9 +122,6 @@ static const Scanner_Model mustek_A2nu2_model = {
 };
 
 
-static SANE_Byte * g_pNegImageData = NULL;
-static unsigned int g_dwAlreadyGetNegLines;
-
 static SANE_Bool IsTAConnected (void);
 
 
@@ -485,83 +482,6 @@ SetParameters (TARGETIMAGE * pSetParameters)
   return SANE_TRUE;
 }
 
-static unsigned short
-AdjustColorComponent (SANE_Byte c, SANE_Byte min, SANE_Byte max,
-		      SANE_Byte range)
-{
-  if (range == 0)
-    c = max;
-  else if (c < min)
-    c = 0;
-  else
-    {
-      float fmax = (float) ((c - min) * 255) / range;
-      c = (unsigned short) fmax;
-      if ((fmax - c) >= 0.5)
-	c++;
-    }
-  return c;
-}
-
-static void
-AutoLevel (SANE_Byte * pSource, unsigned short ScanLines,
-	   unsigned int BytesPerLine)
-{
-  unsigned int i, j;
-  unsigned int tLines;
-  SANE_Byte R, G, B;
-  SANE_Byte max_R = 0, max_G = 0, max_B = 0;
-  SANE_Byte min_R = 255, min_G = 255, min_B = 255;
-  SANE_Byte range_R, range_G, range_B;
-  unsigned int iWidth = BytesPerLine / 3;
-
-  DBG (DBG_FUNC, "AutoLevel: start\n");
-
-  /* find min and max values for each color component */
-  for (j = 0, tLines = 0; j < ScanLines; j++, tLines += BytesPerLine)
-    {
-      for (i = 0; i < iWidth; i++)
-	{
-	  R = pSource[tLines + i * 3 + 2];
-	  G = pSource[tLines + i * 3 + 1];
-	  B = pSource[tLines + i * 3];
-
-	  max_R = _MAX (R, max_R);
-	  max_G = _MAX (G, max_G);
-	  max_B = _MAX (B, max_B);
-
-	  min_R = _MIN (R, min_R);
-	  min_G = _MIN (G, min_G);
-	  min_B = _MIN (B, min_B);
-	}
-    }
-
-  range_R = max_R - min_R;
-  range_G = max_G - min_G;
-  range_B = max_B - min_B;
-
-  /* stretch histogram */
-  for (j = 0, tLines = 0; j < ScanLines; j++, tLines += BytesPerLine)
-    {
-      for (i = 0; i < iWidth; i++)
-	{
-	  R = pSource[tLines + i * 3 + 2];
-	  G = pSource[tLines + i * 3 + 1];
-	  B = pSource[tLines + i * 3];
-
-	  R = AdjustColorComponent (R, min_R, max_R, range_R);
-	  G = AdjustColorComponent (G, min_G, max_G, range_G);
-	  B = AdjustColorComponent (B, min_B, max_B, range_B);
-
-	  pSource[tLines + i * 3 + 2] = R;
-	  pSource[tLines + i * 3 + 1] = G;
-	  pSource[tLines + i * 3] = B;
-	}
-    }
-
-  DBG (DBG_FUNC, "AutoLevel: exit\n");
-}
-
 static SANE_Bool
 ReadScannedData (IMAGEROWS * pImageRows, TARGETIMAGE * pTarget)
 {
@@ -575,58 +495,15 @@ ReadScannedData (IMAGEROWS * pImageRows, TARGETIMAGE * pTarget)
   Rows = pImageRows->wWantedLineNum;
   DBG (DBG_INFO, "ReadScannedData: wanted rows = %d\n", Rows);
 
-  if (pTarget->ssScanSource == SS_NEGATIVE)
+  if (!MustScanner_GetRows (pImageRows->pBuffer, &Rows, isRGBInvert))
+    return SANE_FALSE;
+  pImageRows->wXferedLineNum = Rows;
+
+  if ((pTarget->cmColorMode == CM_TEXT) ||
+      (pTarget->ssScanSource == SS_NEGATIVE))
     {
-      DBG (DBG_INFO, "ReadScannedData: deal with the Negative\n");
+      for (i = 0; i < (Rows * pTarget->dwBytesPerRow); i++)
-
+	pImageRows->pBuffer[i] ^= 0xff;
-      if (pTarget->cmColorMode != CM_RGB24)
-	return SANE_FALSE;
-
-      if (!g_pNegImageData)
-	{
-	  unsigned int TotalImageSize = g_SWHeight * pTarget->dwBytesPerRow;
-	  g_dwAlreadyGetNegLines = 0;
-	  g_pNegImageData = malloc (TotalImageSize);
-	  if (!g_pNegImageData)
-	    {
-	      DBG (DBG_ERR, "ReadScannedData: error allocating memory\n");
-	      return SANE_FALSE;
-	    }
-
-	  if (!MustScanner_GetRows (g_pNegImageData, &g_SWHeight, isRGBInvert))
-	    return SANE_FALSE;
-	  DBG (DBG_INFO, "ReadScannedData: get image data is over!\n");
-
-	  for (i = 0; i < TotalImageSize; i++)
-	    g_pNegImageData[i] ^= 0xff;
-	  AutoLevel (g_pNegImageData, g_SWHeight, pTarget->dwBytesPerRow);
-	  DBG (DBG_INFO, "ReadScannedData: autolevel is ok\n");
-	}
-
-      memcpy (pImageRows->pBuffer, g_pNegImageData +
-	      (pTarget->dwBytesPerRow * g_dwAlreadyGetNegLines),
-	      pTarget->dwBytesPerRow * Rows);
-      pImageRows->wXferedLineNum = Rows;
-      DBG (DBG_INFO, "ReadScannedData: copy the data over!\n");
-
-      g_dwAlreadyGetNegLines += Rows;
-      if (g_dwAlreadyGetNegLines >= g_SWHeight)
-	{
-	  free (g_pNegImageData);
-	  g_pNegImageData = NULL;
-	}
-    }
-  else
-    {
-      if (!MustScanner_GetRows (pImageRows->pBuffer, &Rows, isRGBInvert))
-	return SANE_FALSE;
-      pImageRows->wXferedLineNum = Rows;
-
-      if (pTarget->cmColorMode == CM_TEXT)
-	{
-	  for (i = 0; i < (Rows * pTarget->dwBytesPerRow); i++)
-	    pImageRows->pBuffer[i] ^= 0xff;
-	}
     }
 
   DBG (DBG_FUNC, "ReadScannedData: exit\n");