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
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
|
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <gif_lib.h>
#include "readers.h"
struct gif_state {
FILE *infile;
GifFileType *gif;
GifPixelType *row;
GifPixelType *il;
int w,h;
};
static GifRecordType
gif_fileread(struct gif_state *h)
{
GifRecordType RecordType;
GifByteType *Extension;
int ExtCode, rc;
char *type;
for (;;) {
if (GIF_ERROR == DGifGetRecordType(h->gif,&RecordType)) {
if (debug)
fprintf(stderr,"gif: DGifGetRecordType failed\n");
PrintGifError();
return -1;
}
switch (RecordType) {
case IMAGE_DESC_RECORD_TYPE:
if (debug)
fprintf(stderr,"gif: IMAGE_DESC_RECORD_TYPE found\n");
return RecordType;
case EXTENSION_RECORD_TYPE:
if (debug)
fprintf(stderr,"gif: EXTENSION_RECORD_TYPE found\n");
for (rc = DGifGetExtension(h->gif,&ExtCode,&Extension);
NULL != Extension;
rc = DGifGetExtensionNext(h->gif,&Extension)) {
if (rc == GIF_ERROR) {
if (debug)
fprintf(stderr,"gif: DGifGetExtension failed\n");
PrintGifError();
return -1;
}
if (debug) {
switch (ExtCode) {
case COMMENT_EXT_FUNC_CODE: type="comment"; break;
case GRAPHICS_EXT_FUNC_CODE: type="graphics"; break;
case PLAINTEXT_EXT_FUNC_CODE: type="plaintext"; break;
case APPLICATION_EXT_FUNC_CODE: type="appl"; break;
default: type="???"; break;
}
fprintf(stderr,"gif: extcode=0x%x [%s]\n",ExtCode,type);
}
}
break;
case TERMINATE_RECORD_TYPE:
if (debug)
fprintf(stderr,"gif: TERMINATE_RECORD_TYPE found\n");
return RecordType;
default:
if (debug)
fprintf(stderr,"gif: unknown record type [%d]\n",RecordType);
return -1;
}
}
}
#if 0
static void
gif_skipimage(struct gif_state *h)
{
unsigned char *line;
int i;
if (debug)
fprintf(stderr,"gif: skipping image record ...\n");
DGifGetImageDesc(h->gif);
line = malloc(h->gif->SWidth);
for (i = 0; i < h->gif->SHeight; i++)
DGifGetLine(h->gif, line, h->gif->SWidth);
free(line);
}
#endif
static void*
gif_init(FILE *fp, char *filename, unsigned int page,
struct ida_image_info *info, int thumbnail)
{
struct gif_state *h;
GifRecordType RecordType;
int i, image = 0;
h = malloc(sizeof(*h));
memset(h,0,sizeof(*h));
h->infile = fp;
h->gif = DGifOpenFileHandle(fileno(fp));
h->row = malloc(h->gif->SWidth * sizeof(GifPixelType));
while (0 == image) {
RecordType = gif_fileread(h);
switch (RecordType) {
case IMAGE_DESC_RECORD_TYPE:
if (GIF_ERROR == DGifGetImageDesc(h->gif)) {
if (debug)
fprintf(stderr,"gif: DGifGetImageDesc failed\n");
PrintGifError();
}
if (NULL == h->gif->SColorMap &&
NULL == h->gif->Image.ColorMap) {
if (debug)
fprintf(stderr,"gif: oops: no colormap found\n");
goto oops;
}
#if 0
info->width = h->w = h->gif->SWidth;
info->height = h->h = h->gif->SHeight;
#else
info->width = h->w = h->gif->Image.Width;
info->height = h->h = h->gif->Image.Height;
#endif
info->npages = 1;
image = 1;
if (debug)
fprintf(stderr,"gif: reading image record ...\n");
if (h->gif->Image.Interlace) {
if (debug)
fprintf(stderr,"gif: interlaced\n");
h->il = malloc(h->w * h->h * sizeof(GifPixelType));
for (i = 0; i < h->h; i += 8)
DGifGetLine(h->gif, h->il + h->w*i,h->w);
for (i = 4; i < h->gif->SHeight; i += 8)
DGifGetLine(h->gif, h->il + h->w*i,h->w);
for (i = 2; i < h->gif->SHeight; i += 4)
DGifGetLine(h->gif, h->il + h->w*i,h->w);
}
break;
case TERMINATE_RECORD_TYPE:
default:
goto oops;
}
}
if (0 == info->width || 0 == info->height)
goto oops;
if (debug)
fprintf(stderr,"gif: s=%dx%d i=%dx%d\n",
h->gif->SWidth,h->gif->SHeight,
h->gif->Image.Width,h->gif->Image.Height);
return h;
oops:
if (debug)
fprintf(stderr,"gif: fatal error, aborting\n");
DGifCloseFile(h->gif);
fclose(h->infile);
free(h->row);
free(h);
return NULL;
}
static void
gif_read(unsigned char *dst, unsigned int line, void *data)
{
struct gif_state *h = data;
GifColorType *cmap;
int x;
if (h->gif->Image.Interlace) {
if (line % 2) {
DGifGetLine(h->gif, h->row, h->w);
} else {
memcpy(h->row, h->il + h->w * line, h->w);
}
} else {
DGifGetLine(h->gif, h->row, h->w);
}
cmap = h->gif->Image.ColorMap ?
h->gif->Image.ColorMap->Colors : h->gif->SColorMap->Colors;
for (x = 0; x < h->w; x++) {
dst[0] = cmap[h->row[x]].Red;
dst[1] = cmap[h->row[x]].Green;
dst[2] = cmap[h->row[x]].Blue;
dst += 3;
}
}
static void
gif_done(void *data)
{
struct gif_state *h = data;
if (debug)
fprintf(stderr,"gif: done, cleaning up\n");
DGifCloseFile(h->gif);
fclose(h->infile);
if (h->il)
free(h->il);
free(h->row);
free(h);
}
static struct ida_loader gif_loader = {
magic: "GIF",
moff: 0,
mlen: 3,
name: "libungif",
init: gif_init,
read: gif_read,
done: gif_done,
};
static void __init init_rd(void)
{
load_register(&gif_loader);
}
|
