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[python.git] / Modules / imgfile.c
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2 /* IMGFILE module - Interface to sgi libimage */
4 /* XXX This module should be done better at some point. It should return
5 ** an object of image file class, and have routines to manipulate these
6 ** image files in a neater way (so you can get rgb images off a greyscale
7 ** file, for instance, or do a straight display without having to get the
8 ** image bits into python, etc).
9 **
10 ** Warning: this module is very non-reentrant (esp. the readscaled stuff)
13 #include "Python.h"
15 #include <gl/image.h>
17 #include "/usr/people/4Dgifts/iristools/include/izoom.h"
19 /* Bunch of missing extern decls; keep gcc -Wall happy... */
20 extern void i_seterror();
21 extern void iclose();
22 extern void filterzoom();
23 extern void putrow();
24 extern void getrow();
26 static PyObject * ImgfileError; /* Exception we raise for various trouble */
28 static int top_to_bottom; /* True if we want top-to-bottom images */
30 /* The image library does not always call the error hander :-(,
31 therefore we have a global variable indicating that it was called.
32 It is cleared by imgfile_open(). */
34 static int error_called;
37 /* The error handler */
39 static void
40 imgfile_error(char *str)
42 PyErr_SetString(ImgfileError, str);
43 error_called = 1;
44 return; /* To imglib, which will return a failure indicator */
48 /* Open an image file and return a pointer to it.
49 Make sure we raise an exception if we fail. */
51 static IMAGE *
52 imgfile_open(char *fname)
54 IMAGE *image;
55 i_seterror(imgfile_error);
56 error_called = 0;
57 errno = 0;
58 if ( (image = iopen(fname, "r")) == NULL ) {
59 /* Error may already be set by imgfile_error */
60 if ( !error_called ) {
61 if (errno)
62 PyErr_SetFromErrno(ImgfileError);
63 else
64 PyErr_SetString(ImgfileError,
65 "Can't open image file");
67 return NULL;
69 return image;
72 static PyObject *
73 imgfile_ttob(PyObject *self, PyObject *args)
75 int newval;
76 PyObject *rv;
78 if (!PyArg_ParseTuple(args, "i:ttob", &newval))
79 return NULL;
80 rv = PyInt_FromLong(top_to_bottom);
81 top_to_bottom = newval;
82 return rv;
85 static PyObject *
86 imgfile_read(PyObject *self, PyObject *args)
88 char *fname;
89 PyObject *rv;
90 int xsize, ysize, zsize;
91 char *cdatap;
92 long *idatap;
93 static short rs[8192], gs[8192], bs[8192];
94 int x, y;
95 IMAGE *image;
96 int yfirst, ylast, ystep;
98 if ( !PyArg_ParseTuple(args, "s:read", &fname) )
99 return NULL;
101 if ( (image = imgfile_open(fname)) == NULL )
102 return NULL;
104 if ( image->colormap != CM_NORMAL ) {
105 iclose(image);
106 PyErr_SetString(ImgfileError,
107 "Can only handle CM_NORMAL images");
108 return NULL;
110 if ( BPP(image->type) != 1 ) {
111 iclose(image);
112 PyErr_SetString(ImgfileError,
113 "Can't handle imgfiles with bpp!=1");
114 return NULL;
116 xsize = image->xsize;
117 ysize = image->ysize;
118 zsize = image->zsize;
119 if ( zsize != 1 && zsize != 3) {
120 iclose(image);
121 PyErr_SetString(ImgfileError,
122 "Can only handle 1 or 3 byte pixels");
123 return NULL;
125 if ( xsize > 8192 ) {
126 iclose(image);
127 PyErr_SetString(ImgfileError,
128 "Can't handle image with > 8192 columns");
129 return NULL;
132 if ( zsize == 3 ) zsize = 4;
133 rv = PyString_FromStringAndSize((char *)NULL, xsize*ysize*zsize);
134 if ( rv == NULL ) {
135 iclose(image);
136 return NULL;
138 cdatap = PyString_AsString(rv);
139 idatap = (long *)cdatap;
141 if (top_to_bottom) {
142 yfirst = ysize-1;
143 ylast = -1;
144 ystep = -1;
145 } else {
146 yfirst = 0;
147 ylast = ysize;
148 ystep = 1;
150 for ( y=yfirst; y != ylast && !error_called; y += ystep ) {
151 if ( zsize == 1 ) {
152 getrow(image, rs, y, 0);
153 for(x=0; x<xsize; x++ )
154 *cdatap++ = rs[x];
155 } else {
156 getrow(image, rs, y, 0);
157 getrow(image, gs, y, 1);
158 getrow(image, bs, y, 2);
159 for(x=0; x<xsize; x++ )
160 *idatap++ = (rs[x] & 0xff) |
161 ((gs[x] & 0xff)<<8) |
162 ((bs[x] & 0xff)<<16);
165 iclose(image);
166 if ( error_called ) {
167 Py_DECREF(rv);
168 return NULL;
170 return rv;
173 static IMAGE *glob_image;
174 static long *glob_datap;
175 static int glob_width, glob_z, glob_ysize;
177 static void
178 xs_get(short *buf, int y)
180 if (top_to_bottom)
181 getrow(glob_image, buf, (glob_ysize-1-y), glob_z);
182 else
183 getrow(glob_image, buf, y, glob_z);
186 static void
187 xs_put_c(short *buf, int y)
189 char *datap = (char *)glob_datap + y*glob_width;
190 int width = glob_width;
192 while ( width-- )
193 *datap++ = (*buf++) & 0xff;
196 static void
197 xs_put_0(short *buf, int y)
199 long *datap = glob_datap + y*glob_width;
200 int width = glob_width;
202 while ( width-- )
203 *datap++ = (*buf++) & 0xff;
205 static void
206 xs_put_12(short *buf, int y)
208 long *datap = glob_datap + y*glob_width;
209 int width = glob_width;
211 while ( width-- )
212 *datap++ |= ((*buf++) & 0xff) << (glob_z*8);
215 static void
216 xscale(IMAGE *image, int xsize, int ysize, int zsize,
217 long *datap, int xnew, int ynew, int fmode, double blur)
219 glob_image = image;
220 glob_datap = datap;
221 glob_width = xnew;
222 glob_ysize = ysize;
223 if ( zsize == 1 ) {
224 glob_z = 0;
225 filterzoom(xs_get, xs_put_c, xsize, ysize,
226 xnew, ynew, fmode, blur);
227 } else {
228 glob_z = 0;
229 filterzoom(xs_get, xs_put_0, xsize, ysize,
230 xnew, ynew, fmode, blur);
231 glob_z = 1;
232 filterzoom(xs_get, xs_put_12, xsize, ysize,
233 xnew, ynew, fmode, blur);
234 glob_z = 2;
235 filterzoom(xs_get, xs_put_12, xsize, ysize,
236 xnew, ynew, fmode, blur);
241 static PyObject *
242 imgfile_readscaled(PyObject *self, PyObject *args)
244 char *fname;
245 PyObject *rv;
246 int xsize, ysize, zsize;
247 char *cdatap;
248 long *idatap;
249 static short rs[8192], gs[8192], bs[8192];
250 int x, y;
251 int xwtd, ywtd, xorig, yorig;
252 float xfac, yfac;
253 IMAGE *image;
254 char *filter;
255 double blur = 1.0;
256 int extended;
257 int fmode = 0;
258 int yfirst, ylast, ystep;
261 ** Parse args. Funny, since arg 4 and 5 are optional
262 ** (filter name and blur factor). Also, 4 or 5 arguments indicates
263 ** extended scale algorithm in stead of simple-minded pixel drop/dup.
265 extended = PyTuple_Size(args) >= 4;
266 if ( !PyArg_ParseTuple(args, "sii|sd",
267 &fname, &xwtd, &ywtd, &filter, &blur) )
268 return NULL;
271 ** Check parameters, open file and check type, rows, etc.
273 if ( extended ) {
274 if ( strcmp(filter, "impulse") == 0 )
275 fmode = IMPULSE;
276 else if ( strcmp( filter, "box") == 0 )
277 fmode = BOX;
278 else if ( strcmp( filter, "triangle") == 0 )
279 fmode = TRIANGLE;
280 else if ( strcmp( filter, "quadratic") == 0 )
281 fmode = QUADRATIC;
282 else if ( strcmp( filter, "gaussian") == 0 )
283 fmode = GAUSSIAN;
284 else {
285 PyErr_SetString(ImgfileError, "Unknown filter type");
286 return NULL;
290 if ( (image = imgfile_open(fname)) == NULL )
291 return NULL;
293 if ( image->colormap != CM_NORMAL ) {
294 iclose(image);
295 PyErr_SetString(ImgfileError,
296 "Can only handle CM_NORMAL images");
297 return NULL;
299 if ( BPP(image->type) != 1 ) {
300 iclose(image);
301 PyErr_SetString(ImgfileError,
302 "Can't handle imgfiles with bpp!=1");
303 return NULL;
305 xsize = image->xsize;
306 ysize = image->ysize;
307 zsize = image->zsize;
308 if ( zsize != 1 && zsize != 3) {
309 iclose(image);
310 PyErr_SetString(ImgfileError,
311 "Can only handle 1 or 3 byte pixels");
312 return NULL;
314 if ( xsize > 8192 ) {
315 iclose(image);
316 PyErr_SetString(ImgfileError,
317 "Can't handle image with > 8192 columns");
318 return NULL;
321 if ( zsize == 3 ) zsize = 4;
322 rv = PyString_FromStringAndSize(NULL, xwtd*ywtd*zsize);
323 if ( rv == NULL ) {
324 iclose(image);
325 return NULL;
327 PyFPE_START_PROTECT("readscaled", return 0)
328 xfac = (float)xsize/(float)xwtd;
329 yfac = (float)ysize/(float)ywtd;
330 PyFPE_END_PROTECT(yfac)
331 cdatap = PyString_AsString(rv);
332 idatap = (long *)cdatap;
334 if ( extended ) {
335 xscale(image, xsize, ysize, zsize,
336 idatap, xwtd, ywtd, fmode, blur);
337 } else {
338 if (top_to_bottom) {
339 yfirst = ywtd-1;
340 ylast = -1;
341 ystep = -1;
342 } else {
343 yfirst = 0;
344 ylast = ywtd;
345 ystep = 1;
347 for ( y=yfirst; y != ylast && !error_called; y += ystep ) {
348 yorig = (int)(y*yfac);
349 if ( zsize == 1 ) {
350 getrow(image, rs, yorig, 0);
351 for(x=0; x<xwtd; x++ ) {
352 *cdatap++ = rs[(int)(x*xfac)];
354 } else {
355 getrow(image, rs, yorig, 0);
356 getrow(image, gs, yorig, 1);
357 getrow(image, bs, yorig, 2);
358 for(x=0; x<xwtd; x++ ) {
359 xorig = (int)(x*xfac);
360 *idatap++ = (rs[xorig] & 0xff) |
361 ((gs[xorig] & 0xff)<<8) |
362 ((bs[xorig] & 0xff)<<16);
367 iclose(image);
368 if ( error_called ) {
369 Py_DECREF(rv);
370 return NULL;
372 return rv;
375 static PyObject *
376 imgfile_getsizes(PyObject *self, PyObject *args)
378 char *fname;
379 PyObject *rv;
380 IMAGE *image;
382 if ( !PyArg_ParseTuple(args, "s:getsizes", &fname) )
383 return NULL;
385 if ( (image = imgfile_open(fname)) == NULL )
386 return NULL;
387 rv = Py_BuildValue("(iii)", image->xsize, image->ysize, image->zsize);
388 iclose(image);
389 return rv;
392 static PyObject *
393 imgfile_write(PyObject *self, PyObject *args)
395 IMAGE *image;
396 char *fname;
397 int xsize, ysize, zsize, len;
398 char *cdatap;
399 long *idatap;
400 short rs[8192], gs[8192], bs[8192];
401 short r, g, b;
402 long rgb;
403 int x, y;
404 int yfirst, ylast, ystep;
407 if ( !PyArg_ParseTuple(args, "ss#iii:write",
408 &fname, &cdatap, &len, &xsize, &ysize, &zsize) )
409 return NULL;
411 if ( zsize != 1 && zsize != 3 ) {
412 PyErr_SetString(ImgfileError,
413 "Can only handle 1 or 3 byte pixels");
414 return NULL;
416 if ( len != xsize * ysize * (zsize == 1 ? 1 : 4) ) {
417 PyErr_SetString(ImgfileError, "Data does not match sizes");
418 return NULL;
420 if ( xsize > 8192 ) {
421 PyErr_SetString(ImgfileError,
422 "Can't handle image with > 8192 columns");
423 return NULL;
426 error_called = 0;
427 errno = 0;
428 image =iopen(fname, "w", RLE(1), 3, xsize, ysize, zsize);
429 if ( image == 0 ) {
430 if ( ! error_called ) {
431 if (errno)
432 PyErr_SetFromErrno(ImgfileError);
433 else
434 PyErr_SetString(ImgfileError,
435 "Can't create image file");
437 return NULL;
440 idatap = (long *)cdatap;
442 if (top_to_bottom) {
443 yfirst = ysize-1;
444 ylast = -1;
445 ystep = -1;
446 } else {
447 yfirst = 0;
448 ylast = ysize;
449 ystep = 1;
451 for ( y=yfirst; y != ylast && !error_called; y += ystep ) {
452 if ( zsize == 1 ) {
453 for( x=0; x<xsize; x++ )
454 rs[x] = *cdatap++;
455 putrow(image, rs, y, 0);
456 } else {
457 for( x=0; x<xsize; x++ ) {
458 rgb = *idatap++;
459 r = rgb & 0xff;
460 g = (rgb >> 8 ) & 0xff;
461 b = (rgb >> 16 ) & 0xff;
462 rs[x] = r;
463 gs[x] = g;
464 bs[x] = b;
466 putrow(image, rs, y, 0);
467 putrow(image, gs, y, 1);
468 putrow(image, bs, y, 2);
471 iclose(image);
472 if ( error_called )
473 return NULL;
474 Py_INCREF(Py_None);
475 return Py_None;
480 static PyMethodDef imgfile_methods[] = {
481 { "getsizes", imgfile_getsizes, METH_VARARGS },
482 { "read", imgfile_read, METH_VARARGS },
483 { "readscaled", imgfile_readscaled, METH_VARARGS},
484 { "write", imgfile_write, METH_VARARGS },
485 { "ttob", imgfile_ttob, METH_VARARGS },
486 { NULL, NULL } /* Sentinel */
490 void
491 initimgfile(void)
493 PyObject *m, *d;
494 m = Py_InitModule("imgfile", imgfile_methods);
495 if (m == NULL)
496 return;
497 d = PyModule_GetDict(m);
498 ImgfileError = PyErr_NewException("imgfile.error", NULL, NULL);
499 if (ImgfileError != NULL)
500 PyDict_SetItemString(d, "error", ImgfileError);