Add option for setting luminance & chrominance quality independently (currently only...

git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@248 632fc199-4ca6-4c93-a231-07263d6284db

diff --cc cjpeg.1
index d175a961c6a9c0f3f0884f20bf29b7ad165ad31b,01bfa2595b356a59365f2fd458294e7d2a09225b..3aee8079f61a418ce5167b4613f14beb228ff346
--- 1/cjpeg.1
--- 2/cjpeg.1
+++ b/cjpeg.1
@@@ -276,11 -314,8 +301,10 @@@ Communications of the ACM, April 1991 (
  .SH AUTHOR
  Independent JPEG Group
  .SH BUGS
 +Arithmetic coding is not supported for legal reasons.
 +.PP
  GIF input files are no longer supported, to avoid the Unisys LZW patent.
- Use a Unisys-licensed program if you need to read a GIF file.  (Conversion
- of GIF files to JPEG is usually a bad idea anyway.)
+ (Conversion of GIF files to JPEG is usually a bad idea anyway.)
  .PP
  Not all variants of BMP and Targa file formats are supported.
  .PP

diff --cc cjpeg.c
index 648abf2dc9e29acb2f6db68c967d6b0aebcac41b,b9d57eb5c863f74a30a3441c172f8161db44662e..3daa259a70e549487684523eaf13d9f9ee5fbc47
--- 1/cjpeg.c
--- 2/cjpeg.c
+++ b/cjpeg.c
@@@ -2,7 -2,7 +2,8 @@@
   * cjpeg.c
   *
   * Copyright (C) 1991-1998, Thomas G. Lane.
+  * Modified 2003-2008 by Guido Vollbeding.
 + * 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.
   *
@@@ -387,7 -383,15 +380,7 @@@ parse_switches (j_compress_ptr cinfo, i
         * default sampling factors.
         */
  
-     } else if (keymatch(arg, "scans", 2)) {
 -    } else if (keymatch(arg, "scale", 4)) {
 -      /* Scale the image by a fraction M/N. */
 -      if (++argn >= argc)     /* advance to next argument */
 -      usage();
 -      if (sscanf(argv[argn], "%d/%d",
 -               &cinfo->scale_num, &cinfo->scale_denom) != 2)
 -      usage();
 -
+     } else if (keymatch(arg, "scans", 4)) {
        /* Set scan script. */
  #ifdef C_MULTISCAN_FILES_SUPPORTED
        if (++argn >= argc)     /* advance to next argument */

diff --cc rdswitch.c
index 4f4bb4f58994719124b0b1fa7827389307126a59,7a839af7a4f836bfc46dc9319e43d4fefae8cd3d..d34b4007d3a373ad1a3b586c339ad565edf21392
--- 1/rdswitch.c
--- 2/rdswitch.c
+++ b/rdswitch.c
@@@ -69,9 -70,8 +70,12 @@@ read_text_integer (FILE * file, long * 
  }
  
  
++#if JPEG_LIB_VERSION < 70
++static int q_scale_factor = 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 -108,8 +112,12 @@@
        }
        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, force_baseline);
++#endif
      tblno++;
    }
  
@@@ -262,6 -263,38 +271,46 @@@ bogus
  #endif /* C_MULTISCAN_FILES_SUPPORTED */
  
  
+ 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);
++#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);
++#endif
+     }
+   }
++#if JPEG_LIB_VERSION >= 70
+   jpeg_default_qtables(cinfo, force_baseline);
++#else
++  jpeg_set_quality(cinfo, val, force_baseline);
++#endif
+   return TRUE;
+ }
+ 
+ 
  GLOBAL(boolean)
  set_quant_slots (j_compress_ptr cinfo, char *arg)
  /* Process a quantization-table-selectors parameter string, of the form