Add -7bit

git-svn-id: http://svn.code.sf.net/p/netpbm/code/trunk@4579 9d0c8265-081b-0410-96cb-a4ca84ce46f8

2 files changed, 109 insertions, 77 deletions

diff --git a/converter/ppm/ppmtosixel.c b/converter/ppm/ppmtosixel.c
index 5f361e45..b2491e23 100644
--- a/converter/ppm/ppmtosixel.c
+++ b/converter/ppm/ppmtosixel.c
@@ -8,12 +8,15 @@
 ** copyright notice and this permission notice appear in supporting
 ** documentation.  This software is provided "as is" without express or
 ** implied warranty.
+**
+** "-7bit" option added August 2023 by Scott Pakin <scott+pbm@pakin.org>.
 */
 
 #include "ppm.h"
 
+static void init_escape_sequences ARGS((const int nbits));
 static void WriteHeader ARGS((void));
-static void WriteColorMap 
+static void WriteColorMap
   ARGS((colorhist_vector chv, int colors, pixval maxval));
 static void WriteRawImage ARGS((colorhash_table cht, int rows, int cols));
 static void WritePackedImage ARGS((colorhash_table cht, int rows, int cols));
@@ -21,17 +24,17 @@ static void WriteEnd ARGS((void));
 #define MAXVAL 100
 #define MAXCOLORS 256
 
-#define DCS '\220'   /* Device Control String */
-#define ST  '\234'   /* String Terminator */
-#define CSI '\233'   /* Control String Introducer */
-#define ESC '\033'   /* Escape character */
+/* Named escape sequences */
+static struct {
+  const char * DCS;   /* Device Control String */
+  const char * ST;    /* String Terminator */
+  const char * CSI;   /* Control String Introducer */
+  const char * ESC;   /* Escape character */
+} eseqs;
 
 static pixel** pixels;   /* stored ppm pixmap input */
 static colorhash_table cht;
 int margin;
-
-
-
 int
 main( argc, argv )
     int argc;
@@ -40,6 +43,7 @@ main( argc, argv )
     FILE* ifp;
     int argn, rows, cols, colors;
     int raw;
+    int nbits;
     pixval maxval;
     colorhist_vector chv;
     const char* const usage = "[-raw] [-margin] [ppmfile]";
@@ -50,29 +54,32 @@ main( argc, argv )
     argn = 1;
     raw = 0;
     margin = 0;
+    nbits = 8;
 
     /* Parse args. */
     while ( argn < argc && argv[argn][0] == '-' && argv[argn][1] != '\0' )
-	{
-	if ( pm_keymatch( argv[argn], "-raw", 2 ) )
-	    raw = 1;
-	else if ( pm_keymatch( argv[argn], "-margin", 2 ) )
-	    margin = 1;
-	else
-	    pm_usage( usage );
-	++argn;
-	}
+        {
+        if ( pm_keymatch( argv[argn], "-raw", 2 ) )
+            raw = 1;
+        else if ( pm_keymatch( argv[argn], "-margin", 2 ) )
+            margin = 1;
+        else if ( pm_keymatch( argv[argn], "-7bit", 2 ) )
+            nbits = 7;
+        else
+            pm_usage( usage );
+        ++argn;
+        }
 
     if ( argn < argc )
-	{
-	ifp = pm_openr( argv[argn] );
-	++argn;
-	}
+        {
+        ifp = pm_openr( argv[argn] );
+        ++argn;
+        }
     else
-	ifp = stdin;
+        ifp = stdin;
 
     if ( argn != argc )
-	pm_usage( usage );
+        pm_usage( usage );
 
     /* Read in the whole ppmfile. */
     pixels = ppm_readppm( ifp, &cols, &rows, &maxval );
@@ -80,25 +87,26 @@ main( argc, argv )
 
     /* Print a warning if we could lose accuracy when rescaling colors. */
     if ( maxval > MAXVAL )
-	pm_message(
-	    "maxval is not %d - automatically rescaling colors", MAXVAL );
+        pm_message(
+            "maxval is not %d - automatically rescaling colors", MAXVAL );
 
     /* Figure out the colormap. */
     pm_message( "computing colormap..." );
     chv = ppm_computecolorhist( pixels, cols, rows, MAXCOLORS, &colors );
     if ( chv == (colorhist_vector) 0 )
-	pm_error( "too many colors - try doing a 'pnmquant %d'", MAXCOLORS );
+        pm_error( "too many colors - try doing a 'pnmquant %d'", MAXCOLORS );
     pm_message( "%d colors found", colors );
 
     /* Make a hash table for fast color lookup. */
     cht = ppm_colorhisttocolorhash( chv, colors );
 
+    init_escape_sequences( nbits );
     WriteHeader();
     WriteColorMap( chv, colors, maxval );
     if ( raw == 1 )
-	WriteRawImage( cht, rows, cols );
+        WriteRawImage( cht, rows, cols );
     else
-	WritePackedImage( cht, rows, cols );
+        WritePackedImage( cht, rows, cols );
     WriteEnd();
 
     /* If the program failed, it previously aborted with nonzero completion
@@ -110,11 +118,32 @@ main( argc, argv )
 
 
 static void
+init_escape_sequences(const int nbits)
+{
+  if (nbits == 8) {
+    eseqs.DCS = "\220";
+    eseqs.ST  = "\234";
+    eseqs.CSI = "\233";
+    eseqs.ESC = "\033";
+  }
+  else if (nbits == 7) {
+    eseqs.DCS = "\033P";
+    eseqs.ST  = "\033\\";
+    eseqs.CSI = "\033[";
+    eseqs.ESC = "\033";
+  }
+  else
+    pm_error("internal error: bad bit count");
+}
+
+
+
+static void
 WriteHeader()
     {
     if ( margin == 1 )
-	printf( "%c%d;%ds", CSI, 14, 72 );
-    printf( "%c", DCS );  /* start with Device Control String */
+        printf( "%s%d;%ds", eseqs.CSI, 14, 72 );
+    printf( "%s", eseqs.DCS );  /* start with Device Control String */
     printf( "0;0;8q" );   /* Horizontal Grid Size at 1/90" and graphics On */
     printf( "\"1;1\n" );  /* set aspect ratio 1:1 */
     }
@@ -128,13 +157,13 @@ WriteColorMap( colorhist_vector chv, int colors, pixval maxval )
     pixel p;
 
     for ( colornum = 0; colornum < colors ; ++colornum )
-	{
-	p = chv[colornum].color;
-	if ( maxval != MAXVAL )
-	    PPM_DEPTH( p, p, maxval, MAXVAL );
-	printf( "#%d;2;%d;%d;%d", colornum,
-	    (int) PPM_GETR( p ), (int) PPM_GETG( p ), (int) PPM_GETB( p ) );
-	}
+        {
+        p = chv[colornum].color;
+        if ( maxval != MAXVAL )
+            PPM_DEPTH( p, p, maxval, MAXVAL );
+        printf( "#%d;2;%d;%d;%d", colornum,
+            (int) PPM_GETR( p ), (int) PPM_GETG( p ), (int) PPM_GETB( p ) );
+        }
     printf( "\n" );
     }
 
@@ -150,14 +179,14 @@ WriteRawImage( cht, rows, cols )
     register pixel* pP;
 
     for ( rownum = 0; rownum < rows; ++rownum )
-	{
-	b = rownum % 6;
-	for ( colnum = 0, pP = pixels[rownum]; colnum < cols; ++colnum, ++pP )
-	    printf( "#%d%c", ppm_lookupcolor(cht, pP), sixel[b] );
-	printf( "$\n" );   /* Carriage Return */
-	if ( b == 5 )
-	    printf( "-\n" );   /* Line Feed (one sixel height) */
-	}
+        {
+        b = rownum % 6;
+        for ( colnum = 0, pP = pixels[rownum]; colnum < cols; ++colnum, ++pP )
+            printf( "#%d%c", ppm_lookupcolor(cht, pP), sixel[b] );
+        printf( "$\n" );   /* Carriage Return */
+        if ( b == 5 )
+            printf( "-\n" );   /* Line Feed (one sixel height) */
+        }
     }
 
 
@@ -172,36 +201,36 @@ WritePackedImage( cht, rows, cols )
     register pixel* pP;
 
     for ( rownum = 0; rownum < rows; ++rownum )
-	{
-	b = rownum % 6;
-	repeat = 1;
-	for ( colnum = 0, pP = pixels[rownum]; colnum < cols; ++colnum, ++pP )
-	    {
-	    thiscolor = ppm_lookupcolor(cht, pP);
-	    if ( colnum == cols -1 )   /* last pixel in row */
-		if ( repeat == 1 )
-		    printf( "#%d%c", thiscolor, sixel[b] );
-		else
-		    printf( "#%d!%d%c", thiscolor, repeat, sixel[b] );
-	    else   /* not last pixel in row */
-		{
-		nextcolor =  ppm_lookupcolor(cht, pP+1);
-		if ( thiscolor == nextcolor )
-		    ++repeat;
-		else
-		    if ( repeat == 1 )
-			printf( "#%d%c", thiscolor, sixel[b] );
-		    else
-		    {
-		    printf( "#%d!%d%c", thiscolor, repeat, sixel[b] );
-		    repeat = 1;
-		    }
-		}
-	    }   /* end column loop */
-	printf( "$\n" );   /* Carriage Return */
-	if ( b == 5 )
-	    printf( "-\n" );   /* Line Feed (one sixel height) */
-	}
+        {
+        b = rownum % 6;
+        repeat = 1;
+        for ( colnum = 0, pP = pixels[rownum]; colnum < cols; ++colnum, ++pP )
+            {
+            thiscolor = ppm_lookupcolor(cht, pP);
+            if ( colnum == cols -1 )   /* last pixel in row */
+                if ( repeat == 1 )
+                    printf( "#%d%c", thiscolor, sixel[b] );
+                else
+                    printf( "#%d!%d%c", thiscolor, repeat, sixel[b] );
+            else   /* not last pixel in row */
+                {
+                nextcolor =  ppm_lookupcolor(cht, pP+1);
+                if ( thiscolor == nextcolor )
+                    ++repeat;
+                else
+                    if ( repeat == 1 )
+                        printf( "#%d%c", thiscolor, sixel[b] );
+                    else
+                    {
+                    printf( "#%d!%d%c", thiscolor, repeat, sixel[b] );
+                    repeat = 1;
+                    }
+                }
+            }   /* end column loop */
+        printf( "$\n" );   /* Carriage Return */
+        if ( b == 5 )
+            printf( "-\n" );   /* Line Feed (one sixel height) */
+        }
     }
 
 
@@ -210,6 +239,6 @@ static void
 WriteEnd()
     {
     if ( margin == 1 )
-	printf ( "%c%d;%ds", CSI, 1, 80 );
-    printf( "%c\n", ST );
+        printf ( "%s%d;%ds", eseqs.CSI, 1, 80 );
+    printf( "%s\n", eseqs.ST );
     }
diff --git a/doc/HISTORY b/doc/HISTORY
index 8bd31abb..3b124c3b 100644
--- a/doc/HISTORY
+++ b/doc/HISTORY
@@ -6,6 +6,9 @@ CHANGE HISTORY
 
 not yet  BJH  Release 11.04.00
 
+              ppmtosixel: Add -7bit, so it works on more terminals, including
+              xterms.  Thanks Scott Pakin.
+
               g3topbm: Add -correctlong
 
               build: Add COMPILED_BY environment variable to control the