Improved compression for Latin-1 encoding in Code 128

This commit is contained in:
hooper114 2009-05-14 22:22:01 +00:00
parent 2170302bf5
commit 76e51fc0ee
3 changed files with 71 additions and 29 deletions

View file

@ -116,7 +116,7 @@ int code16k(struct zint_symbol *symbol, unsigned char source[])
{
char width_pattern[100];
int current_row, rows_needed, flip_flop, looper, first_check, second_check;
int indexliste, indexchaine, pads_needed;
int indexliste, indexchaine, pads_needed, f_state;
char set[160], fset[160], mode, last_set, last_fset, current_set;
unsigned int i, j, k, m, e_count, read, mx_reader, writer;
unsigned int values[160];
@ -133,7 +133,7 @@ int code16k(struct zint_symbol *symbol, unsigned char source[])
if(symbol->input_mode == GS1_MODE) { gs1 = 1; } else { gs1 = 0; }
if(input_length > 157) {
strcpy(symbol->errtxt, "Input too long [231]");
strcpy(symbol->errtxt, "Input too long");
return ERROR_TOO_LONG;
}
@ -161,7 +161,7 @@ int code16k(struct zint_symbol *symbol, unsigned char source[])
do {
j++;
} while(fset[i + j] == 'f');
if((j >= 5) || ((j >= 3) && ((i + j) == input_length))) {
if((j >= 5) || ((j >= 3) && ((i + j) == (input_length - 1)))) {
for(k = 0; k <= j; k++) {
fset[i + k] = 'F';
}
@ -169,6 +169,22 @@ int code16k(struct zint_symbol *symbol, unsigned char source[])
}
}
/* Decide if it is worth reverting to 646 encodation for a few characters */
if(input_length > 1) {
for(i = 1; i < input_length; i++) {
if((fset[i - 1] == 'F') && (fset[i] == ' ')) {
/* Detected a change from 8859-1 to 646 - count how long for */
for(j = 0; (fset[i + j] == ' ') && ((i + j) < input_length); j++);
if((j < 5) || ((j < 3) && ((i + j) == (input_length - 1)))) {
/* Change to shifting back rather than latching back */
for(k = 0; k < j; k++) {
fset[i + k] = 'n';
}
}
}
}
}
/* Detect mode A, B and C characters */
indexliste = 0;
indexchaine = 0;
@ -268,7 +284,7 @@ int code16k(struct zint_symbol *symbol, unsigned char source[])
if((set[i] == 'a') || (set[i] == 'b')) {
glyph_count = glyph_count + 1.0;
}
if(fset[i] == 'f') {
if((fset[i] == 'f') || (fset[i] == 'n')) {
glyph_count = glyph_count + 1.0;
}
if(((set[i] == 'A') || (set[i] == 'B')) || (set[i] == 'C')) {
@ -314,7 +330,7 @@ int code16k(struct zint_symbol *symbol, unsigned char source[])
}
if(glyph_count > 77.0) {
strcpy(symbol->errtxt, "Input too long [232]");
strcpy(symbol->errtxt, "Input too long");
return ERROR_TOO_LONG;
}
@ -350,6 +366,8 @@ int code16k(struct zint_symbol *symbol, unsigned char source[])
bar_characters++;
current_set = set[0];
f_state = 0; /* f_state remembers if we are in Extended ASCII mode (value 1) or
in ISO/IEC 646 mode (value 0) */
if(fset[0] == 'F') {
switch(current_set) {
case 'A':
@ -362,6 +380,7 @@ int code16k(struct zint_symbol *symbol, unsigned char source[])
break;
}
bar_characters += 2;
f_state = 1;
}
read = 0;
@ -395,8 +414,8 @@ int code16k(struct zint_symbol *symbol, unsigned char source[])
}
}
if((read != 0) && (fset[read] != fset[read - 1])) {
if(fset[read] == 'F') {
if(read != 0) {
if((fset[read] == 'F') && (f_state == 0)) {
/* Latch beginning of extended mode */
switch(current_set) {
case 'A':
@ -409,8 +428,9 @@ int code16k(struct zint_symbol *symbol, unsigned char source[])
break;
}
bar_characters += 2;
f_state = 1;
}
if(fset[read - 1] == 'F') {
if((fset[read] == ' ') && (f_state == 1)) {
/* Latch end of extended mode */
switch(current_set) {
case 'A':
@ -423,17 +443,18 @@ int code16k(struct zint_symbol *symbol, unsigned char source[])
break;
}
bar_characters += 2;
f_state = 0;
}
}
if(fset[i] == 'f') {
if((fset[i] == 'f') || (fset[i] == 'n')) {
/* Shift extended mode */
switch(current_set) {
case 'A':
values[bar_characters] = 101;
values[bar_characters] = 101; /* FNC 4 */
break;
case 'B':
values[bar_characters] = 100;
values[bar_characters] = 100; /* FNC 4 */
break;
}
bar_characters++;