Updates libjpeg-turbo to 1.1.90 (r677)

third_party/libjpeg_turbo/rdswitch.c

Index: third_party/libjpeg_turbo/rdswitch.c
===================================================================
--- third_party/libjpeg_turbo/rdswitch.c	(revision 95020)
+++ third_party/libjpeg_turbo/rdswitch.c	(working copy)
@@ -2,6 +2,7 @@
  * rdswitch.c
  *
  * Copyright (C) 1991-1996, Thomas G. Lane.
+ * Copyright (C) 2010, D. R. Commander.
  * This file is part of the Independent JPEG Group's software.
  * For conditions of distribution and use, see the accompanying README file.
  *
@@ -9,6 +10,7 @@
  * command-line switches.  Switches processed here are:
  *	-qtables file		Read quantization tables from text file
  *	-scans file		Read scan script from text file
+ *	-quality N[,N,...]	Set quality ratings
  *	-qslots N[,N,...]	Set component quantization table selectors
  *	-sample HxV[,HxV,...]	Set component sampling factors
  */
@@ -69,9 +71,12 @@
 }
 
 
+#if JPEG_LIB_VERSION < 70
+static int q_scale_factor[NUM_QUANT_TBLS] = {100, 100, 100, 100};
+#endif
+
 GLOBAL(boolean)
-read_quant_tables (j_compress_ptr cinfo, char * filename,
-		   int scale_factor, boolean force_baseline)
+read_quant_tables (j_compress_ptr cinfo, char * filename, boolean force_baseline)
 /* Read a set of quantization tables from the specified file.
  * The file is plain ASCII text: decimal numbers with whitespace between.
  * Comments preceded by '#' may be included in the file.
@@ -108,7 +113,13 @@
       }
       table[i] = (unsigned int) val;
     }
-    jpeg_add_quant_table(cinfo, tblno, table, scale_factor, force_baseline);
+#if JPEG_LIB_VERSION >= 70
+    jpeg_add_quant_table(cinfo, tblno, table, cinfo->q_scale_factor[tblno],
+			 force_baseline);
+#else
+    jpeg_add_quant_table(cinfo, tblno, table, q_scale_factor[tblno],
+                         force_baseline);
+#endif
     tblno++;
   }
 
@@ -262,7 +273,85 @@
 #endif /* C_MULTISCAN_FILES_SUPPORTED */
 
 
+#if JPEG_LIB_VERSION < 70
+/* These are the sample quantization tables given in JPEG spec section K.1.
+ * The spec says that the values given produce "good" quality, and
+ * when divided by 2, "very good" quality.
+ */
+static const unsigned int std_luminance_quant_tbl[DCTSIZE2] = {
+  16,  11,  10,  16,  24,  40,  51,  61,
+  12,  12,  14,  19,  26,  58,  60,  55,
+  14,  13,  16,  24,  40,  57,  69,  56,
+  14,  17,  22,  29,  51,  87,  80,  62,
+  18,  22,  37,  56,  68, 109, 103,  77,
+  24,  35,  55,  64,  81, 104, 113,  92,
+  49,  64,  78,  87, 103, 121, 120, 101,
+  72,  92,  95,  98, 112, 100, 103,  99
+};
+static const unsigned int std_chrominance_quant_tbl[DCTSIZE2] = {
+  17,  18,  24,  47,  99,  99,  99,  99,
+  18,  21,  26,  66,  99,  99,  99,  99,
+  24,  26,  56,  99,  99,  99,  99,  99,
+  47,  66,  99,  99,  99,  99,  99,  99,
+  99,  99,  99,  99,  99,  99,  99,  99,
+  99,  99,  99,  99,  99,  99,  99,  99,
+  99,  99,  99,  99,  99,  99,  99,  99,
+  99,  99,  99,  99,  99,  99,  99,  99
+};
+
+
+LOCAL(void)
+jpeg_default_qtables (j_compress_ptr cinfo, boolean force_baseline)
+{
+  jpeg_add_quant_table(cinfo, 0, std_luminance_quant_tbl,
+		       q_scale_factor[0], force_baseline);
+  jpeg_add_quant_table(cinfo, 1, std_chrominance_quant_tbl,
+		       q_scale_factor[1], force_baseline);
+}
+#endif
+
+
 GLOBAL(boolean)
+set_quality_ratings (j_compress_ptr cinfo, char *arg, boolean force_baseline)
+/* Process a quality-ratings parameter string, of the form
+ *     N[,N,...]
+ * If there are more q-table slots than parameters, the last value is replicated.
+ */
+{
+  int val = 75;			/* default value */
+  int tblno;
+  char ch;
+
+  for (tblno = 0; tblno < NUM_QUANT_TBLS; tblno++) {
+    if (*arg) {
+      ch = ',';			/* if not set by sscanf, will be ',' */
+      if (sscanf(arg, "%d%c", &val, &ch) < 1)
+	return FALSE;
+      if (ch != ',')		/* syntax check */
+	return FALSE;
+      /* Convert user 0-100 rating to percentage scaling */
+#if JPEG_LIB_VERSION >= 70
+      cinfo->q_scale_factor[tblno] = jpeg_quality_scaling(val);
+#else
+      q_scale_factor[tblno] = jpeg_quality_scaling(val);
+#endif
+      while (*arg && *arg++ != ',') /* advance to next segment of arg string */
+	;
+    } else {
+      /* reached end of parameter, set remaining factors to last value */
+#if JPEG_LIB_VERSION >= 70
+      cinfo->q_scale_factor[tblno] = jpeg_quality_scaling(val);
+#else
+      q_scale_factor[tblno] = jpeg_quality_scaling(val);
+#endif
+    }
+  }
+  jpeg_default_qtables(cinfo, force_baseline);
+  return TRUE;
+}
+
+
+GLOBAL(boolean)
 set_quant_slots (j_compress_ptr cinfo, char *arg)
 /* Process a quantization-table-selectors parameter string, of the form
  *     N[,N,...]