about summary refs log tree commit diff
path: root/converter/pgm/pgmtolispm.c
blob: 4309228e60591ff85067200c2cc8053225c8065b (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
/* pgmtolispm.c - read a pgm and write a file acceptable to the
** tv:read-bit-array-file function of TI Explorer and Symbolics Lisp Machines.
**
** Written by Jamie Zawinski based on code (C) 1988 by Jef Poskanzer.
**
** Permission to use, copy, modify, and distribute this software and its
** documentation for any purpose and without fee is hereby granted, provided
** that the above copyright notice appear in all copies and that both that
** copyright notice and this permission notice appear in supporting
** documentation.  This software is provided "as is" without express or
** implied warranty.
**
**   When one writes a multi-plane bitmap with tv:write-bit-array-file, it is
**   usually a color image; but a color map is not written in the file, so we
**   treat this as a graymap instead.  To convert a color image to Lispm
**   format, you must convert it to a pgm, and hand-edit a color map...  Ick.
**
** Feb 2010 afu
** Added dimension check to prevent short int from overflowing
** Changed code style (ANSI-style function definitions, etc.)
*/

#include "pm.h"
#include "pgm.h"

#define LISPM_MAGIC  "This is a BitMap file"
#define INT16MAX 32767


static unsigned int item;
static unsigned int bitsperitem, maxbitsperitem, bitshift;

static unsigned int
depth_to_word_size(unsigned int const depth) {

    /* Lispm architecture specific - if a bitmap is written    */
    /* out with a depth of 5, it really has a depth of 8, and  */
    /* is stored that way in the file.                         */

    unsigned int const wordSize =
        depth ==  1 ?  1 :
        depth ==  2 ?  2 :
        depth <=  4 ?  4 :
        depth <=  8 ?  8 :
        depth <= 16 ? 16 :
        depth <= 32 ? 32 :
        0;

    if (wordSize == 0)
        pm_error("depth was %u, which is not in the range 1-32", depth);

    return wordSize;
}



static void
putinit(unsigned int const cols,
        unsigned int const rows,
        unsigned int const depth) {

    unsigned int const cols32 = ((cols + 31 ) / 32) * 32;

    unsigned int i;

    /* Lispms are able to write bit files that are not mod32 wide, but we   */
    /* don't.  This should be ok, since bit arrays which are not mod32 wide */
    /* are pretty useless on a lispm (can't hand them to bitblt).           */

    if (rows > INT16MAX || cols > INT16MAX || cols32 > INT16MAX)
        pm_error("Input image is too large.");

    printf(LISPM_MAGIC);

    pm_writelittleshort(stdout, cols);
    pm_writelittleshort(stdout, rows);
    pm_writelittleshort(stdout, cols32);
    putchar(depth & 0xFF);

    for (i = 0; i < 9; ++i)
        putchar(0);   /* pad bytes */

    item           = 0;
    bitsperitem    = 0;
    maxbitsperitem = depth_to_word_size(depth);
    bitshift       = 0;
}



static void
putitem(void) {

    pm_writelittlelong(stdout, ~item);

    item        = 0;
    bitsperitem = 0;
    bitshift    = 0;
}



static void
putval(gray const b) {

    if (bitsperitem == 32)
        putitem();

    item        = item | (b << bitshift);
    bitsperitem = bitsperitem + maxbitsperitem;
    bitshift    = bitshift + maxbitsperitem;
}



static void
putrest(void) {

    if (bitsperitem > 0)
        putitem();
}



int
main(int argc, const char * argv[]) {

    FILE * ifP;
    gray * grayrow;
    int rows;
    int cols;
    unsigned int depth;
    int format;
    unsigned int padright;
    unsigned int row;
    gray maxval;
    const char * inputFile;

    pm_proginit(&argc, argv);

    if (argc-1 < 1)
        inputFile = "-";
    else {
        inputFile = argv[1];

        if (argc-1 > 2)
            pm_error("Too many arguments.  The only argument is the optional "
                     "input file name");
    }

    ifP = pm_openr(inputFile);

    pgm_readpgminit(ifP, &cols, &rows, &maxval, &format);

    grayrow = pgm_allocrow(cols);
    depth = pm_maxvaltobits(maxval);

    /* Compute padding to round cols up to the nearest multiple of 32. */
    padright = ((cols + 31) / 32) * 32 - cols;

    putinit(cols, rows, depth);

    for (row = 0; row < rows; ++row) {
        unsigned int col;

        pgm_readpgmrow(ifP, grayrow, cols, maxval, format);

        for (col = 0; col < cols; ++col)
            putval(grayrow[col]);

        for (col = 0; col < padright; ++col)
            putval(0);
    }

    pm_close(ifP);

    putrest();

    return 0;
}