/Modules/imgfile.c

  1
  2/* IMGFILE module - Interface to sgi libimage */
  3
  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)
 11*/
 12
 13#include "Python.h"
 14
 15#include <gl/image.h>
 16
 17#include "/usr/people/4Dgifts/iristools/include/izoom.h"
 18
 19/* Bunch of missing extern decls; keep gcc -Wall happy... */
 20extern void i_seterror();
 21extern void iclose();
 22extern void filterzoom();
 23extern void putrow();
 24extern void getrow();
 25
 26static PyObject * ImgfileError; /* Exception we raise for various trouble */
 27
 28static int top_to_bottom;	/* True if we want top-to-bottom images */
 29
 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(). */
 33
 34static int error_called;
 35
 36
 37/* The error handler */
 38
 39static void
 40imgfile_error(char *str)
 41{
 42	PyErr_SetString(ImgfileError, str);
 43	error_called = 1;
 44	return;	/* To imglib, which will return a failure indicator */
 45}
 46
 47
 48/* Open an image file and return a pointer to it.
 49   Make sure we raise an exception if we fail. */
 50
 51static IMAGE *
 52imgfile_open(char *fname)
 53{
 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");
 66		}
 67		return NULL;
 68	}
 69	return image;
 70}
 71
 72static PyObject *
 73imgfile_ttob(PyObject *self, PyObject *args)
 74{
 75	int newval;
 76	PyObject *rv;
 77    
 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;
 83}
 84
 85static PyObject *
 86imgfile_read(PyObject *self, PyObject *args)
 87{
 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;
 97
 98	if ( !PyArg_ParseTuple(args, "s:read", &fname) )
 99		return NULL;
100    
101	if ( (image = imgfile_open(fname)) == NULL )
102		return NULL;
103    
104	if ( image->colormap != CM_NORMAL ) {
105		iclose(image);
106		PyErr_SetString(ImgfileError,
107				"Can only handle CM_NORMAL images");
108		return NULL;
109	}
110	if ( BPP(image->type) != 1 ) {
111		iclose(image);
112		PyErr_SetString(ImgfileError,
113				"Can't handle imgfiles with bpp!=1");
114		return NULL;
115	}
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;
124	}
125	if ( xsize > 8192 ) {
126		iclose(image);
127		PyErr_SetString(ImgfileError,
128				"Can't handle image with > 8192 columns");
129		return NULL;
130	}
131
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;
137	}
138	cdatap = PyString_AsString(rv);
139	idatap = (long *)cdatap;
140
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;
149	}
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);
163		}
164	}
165	iclose(image);
166	if ( error_called ) {
167		Py_DECREF(rv);
168		return NULL;
169	}
170	return rv;
171}
172
173static IMAGE *glob_image;
174static long *glob_datap;
175static int glob_width, glob_z, glob_ysize;
176
177static void
178xs_get(short *buf, int y)
179{
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);
184}
185
186static void
187xs_put_c(short *buf, int y)
188{
189	char *datap = (char *)glob_datap + y*glob_width;
190	int width = glob_width;
191
192	while ( width-- )
193		*datap++ = (*buf++) & 0xff;
194}
195
196static void
197xs_put_0(short *buf, int y)
198{
199	long *datap = glob_datap + y*glob_width;
200	int width = glob_width;
201
202	while ( width-- )
203		*datap++ = (*buf++) & 0xff;
204}
205static void
206xs_put_12(short *buf, int y)
207{
208	long *datap = glob_datap + y*glob_width;
209	int width = glob_width;
210
211	while ( width-- )
212		*datap++ |= ((*buf++) & 0xff) << (glob_z*8);
213}
214
215static void
216xscale(IMAGE *image, int xsize, int ysize, int zsize,
217       long *datap, int xnew, int ynew, int fmode, double blur)
218{
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);
237	}
238}
239
240
241static PyObject *
242imgfile_readscaled(PyObject *self, PyObject *args)
243{
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;
259
260	/*
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.
264	*/
265	extended = PyTuple_Size(args) >= 4;
266	if ( !PyArg_ParseTuple(args, "sii|sd",
267			       &fname, &xwtd, &ywtd, &filter, &blur) )
268		return NULL;
269
270	/*
271	** Check parameters, open file and check type, rows, etc.
272	*/
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;
287		}
288	}
289    
290	if ( (image = imgfile_open(fname)) == NULL )
291		return NULL;
292    
293	if ( image->colormap != CM_NORMAL ) {
294		iclose(image);
295		PyErr_SetString(ImgfileError,
296				"Can only handle CM_NORMAL images");
297		return NULL;
298	}
299	if ( BPP(image->type) != 1 ) {
300		iclose(image);
301		PyErr_SetString(ImgfileError,
302				"Can't handle imgfiles with bpp!=1");
303		return NULL;
304	}
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;
313	}
314	if ( xsize > 8192 ) {
315		iclose(image);
316		PyErr_SetString(ImgfileError,
317				"Can't handle image with > 8192 columns");
318		return NULL;
319	}
320
321	if ( zsize == 3 ) zsize = 4;
322	rv = PyString_FromStringAndSize(NULL, xwtd*ywtd*zsize);
323	if ( rv == NULL ) {
324		iclose(image);
325		return NULL;
326	}
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;
333
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;
346		}
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)];	
353				}
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);
363				}
364			}
365		}
366	}
367	iclose(image);
368	if ( error_called ) {
369		Py_DECREF(rv);
370		return NULL;
371	}
372	return rv;
373}
374
375static PyObject *
376imgfile_getsizes(PyObject *self, PyObject *args)
377{
378	char *fname;
379	PyObject *rv;
380	IMAGE *image;
381    
382	if ( !PyArg_ParseTuple(args, "s:getsizes", &fname) )
383		return NULL;
384    
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;
390}
391
392static PyObject *
393imgfile_write(PyObject *self, PyObject *args)
394{
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;
405
406
407	if ( !PyArg_ParseTuple(args, "ss#iii:write",
408			  &fname, &cdatap, &len, &xsize, &ysize, &zsize) )
409		return NULL;
410    
411	if ( zsize != 1 && zsize != 3 ) {
412		PyErr_SetString(ImgfileError,
413				"Can only handle 1 or 3 byte pixels");
414		return NULL;
415	}
416	if ( len != xsize * ysize * (zsize == 1 ? 1 : 4) ) {
417		PyErr_SetString(ImgfileError, "Data does not match sizes");
418		return NULL;
419	}
420	if ( xsize > 8192 ) {
421		PyErr_SetString(ImgfileError,
422				"Can't handle image with > 8192 columns");
423		return NULL;
424	}
425
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");
436		}
437		return NULL;
438	}
439
440	idatap = (long *)cdatap;
441    
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;
450	}
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;
465			}
466			putrow(image, rs, y, 0);
467			putrow(image, gs, y, 1);
468			putrow(image, bs, y, 2);
469		}
470	}
471	iclose(image);
472	if ( error_called )
473		return NULL;
474	Py_INCREF(Py_None);
475	return Py_None;
476    
477}
478
479
480static 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 */
487};
488
489
490void
491initimgfile(void)
492{
493	PyObject *m, *d;
494	
495	if (PyErr_WarnPy3k("the imgfile module has been removed in "
496	                   "Python 3.0", 2) < 0)
497	    return;
498	
499	m = Py_InitModule("imgfile", imgfile_methods);
500	if (m == NULL)
501		return;
502	d = PyModule_GetDict(m);
503	ImgfileError = PyErr_NewException("imgfile.error", NULL, NULL);
504	if (ImgfileError != NULL)
505		PyDict_SetItemString(d, "error", ImgfileError);
506}
507
508
509