4 palimg.c - implements paletted images for Imager.
10 Implements paletted images using the new image interface.
14 =item IIM_base_8bit_pal
16 Basic 8-bit/sample paletted image
24 #define PALEXT(im) ((i_img_pal_ext*)((im)->ext_data))
25 static int i_ppix_p(i_img *im, int x, int y, i_color *val);
26 static int i_gpix_p(i_img *im, int x, int y, i_color *val);
27 static int i_glin_p(i_img *im, int l, int r, int y, i_color *vals);
28 static int i_plin_p(i_img *im, int l, int r, int y, i_color *vals);
29 static int i_gsamp_p(i_img *im, int l, int r, int y, i_sample_t *samps, int const *chans, int chan_count);
30 static int i_gpal_p(i_img *pm, int l, int r, int y, i_palidx *vals);
31 static int i_ppal_p(i_img *pm, int l, int r, int y, i_palidx *vals);
32 static int i_addcolors_p(i_img *im, i_color *color, int count);
33 static int i_getcolors_p(i_img *im, int i, i_color *color, int count);
34 static int i_colorcount_p(i_img *im);
35 static int i_maxcolors_p(i_img *im);
36 static int i_findcolor_p(i_img *im, i_color *color, i_palidx *entry);
37 static int i_setcolors_p(i_img *im, int index, i_color *color, int count);
39 static void i_destroy_p(i_img *im);
41 static i_img IIM_base_8bit_pal =
44 0, 0, 0, /* xsize, ysize, bytes */
47 i_palette_type, /* type */
50 { 0, 0, NULL }, /* tags */
53 i_ppix_p, /* i_f_ppix */
54 i_ppixf_fp, /* i_f_ppixf */
55 i_plin_p, /* i_f_plin */
56 i_plinf_fp, /* i_f_plinf */
57 i_gpix_p, /* i_f_gpix */
58 i_gpixf_fp, /* i_f_gpixf */
59 i_glin_p, /* i_f_glin */
60 i_glinf_fp, /* i_f_glinf */
61 i_gsamp_p, /* i_f_gsamp */
62 i_gsampf_fp, /* i_f_gsampf */
64 i_gpal_p, /* i_f_gpal */
65 i_ppal_p, /* i_f_ppal */
66 i_addcolors_p, /* i_f_addcolors */
67 i_getcolors_p, /* i_f_getcolors */
68 i_colorcount_p, /* i_f_colorcount */
69 i_maxcolors_p, /* i_f_maxcolors */
70 i_findcolor_p, /* i_f_findcolor */
71 i_setcolors_p, /* i_f_setcolors */
73 i_destroy_p, /* i_f_destroy */
77 =item i_img_pal_new_low(i_img *im, int x, int y, int channels, int maxpal)
79 Creates a new paletted image.
81 Currently 0 < maxpal <= 256
85 i_img *i_img_pal_new_low(i_img *im, int x, int y, int channels, int maxpal) {
86 i_img_pal_ext *palext;
87 int bytes, line_bytes;
90 if (maxpal < 1 || maxpal > 256) {
91 i_push_error(0, "Maximum of 256 palette entries");
95 i_push_error(0, "Image sizes must be positive");
98 if (channels < 1 || channels > MAXCHANNELS) {
99 i_push_errorf(0, "Channels must be positive and <= %d", MAXCHANNELS);
102 bytes = sizeof(i_palidx) * x * y;
103 if (bytes / y / sizeof(i_palidx) != x) {
104 i_push_error(0, "integer overflow calculating image allocation");
108 /* basic assumption: we can always allocate a buffer representing a
109 line from the image, otherwise we're going to have trouble
110 working with the image */
111 line_bytes = sizeof(i_color) * x;
112 if (line_bytes / x != sizeof(i_color)) {
113 i_push_error(0, "integer overflow calculating scanline allocation");
117 memcpy(im, &IIM_base_8bit_pal, sizeof(i_img));
118 palext = mymalloc(sizeof(i_img_pal_ext));
119 palext->pal = mymalloc(sizeof(i_color) * maxpal);
121 palext->alloc = maxpal;
122 palext->last_found = -1;
123 im->ext_data = palext;
124 i_tags_new(&im->tags);
126 im->idata = mymalloc(im->bytes);
127 im->channels = channels;
128 memset(im->idata, 0, im->bytes);
135 i_img *i_img_pal_new(int x, int y, int channels, int maxpal) {
137 mm_log((1, "i_img_pal_new(x %d, y %d, channels %d, maxpal %d)\n", x, y, channels, maxpal));
138 im = mymalloc(sizeof(i_img));
139 if (!i_img_pal_new_low(im, x, y, channels, maxpal)) {
148 =item i_img_rgb_convert(i_img *targ, i_img *src)
150 Converts paletted data in src to RGB data in targ
154 src must be a paletted image and targ must be an RGB image with the
155 same width, height and channels.
159 static void i_img_rgb_convert(i_img *targ, i_img *src) {
160 i_color *row = mymalloc(sizeof(i_color) * targ->xsize);
162 for (y = 0; y < targ->ysize; ++y) {
163 i_glin(src, 0, src->xsize, y, row);
164 i_plin(targ, 0, src->xsize, y, row);
170 =item i_img_to_rgb_inplace(im)
172 Converts im from a paletted image to an RGB image.
174 The conversion is done in place.
176 The conversion cannot be done for virtual images.
180 int i_img_to_rgb_inplace(i_img *im) {
186 if (im->type == i_direct_type)
187 return 1; /* trivial success */
189 i_img_empty_ch(&temp, im->xsize, im->ysize, im->channels);
190 i_img_rgb_convert(&temp, im);
193 (im->i_f_destroy)(im);
201 =item i_img_to_pal(i_img *im, i_quantize *quant)
203 Converts an RGB image to a paletted image
207 i_img *i_img_to_pal(i_img *src, i_quantize *quant) {
213 quant_makemap(quant, &src, 1);
214 result = quant_translate(quant, src);
218 im = i_img_pal_new(src->xsize, src->ysize, src->channels, quant->mc_size);
220 /* copy things over */
221 memcpy(im->idata, result, im->bytes);
222 PALEXT(im)->count = quant->mc_count;
223 memcpy(PALEXT(im)->pal, quant->mc_colors, sizeof(i_color) * quant->mc_count);
235 =item i_img_to_rgb(i_img *src)
239 i_img *i_img_to_rgb(i_img *src) {
240 i_img *im = i_img_empty_ch(NULL, src->xsize, src->ysize, src->channels);
241 i_img_rgb_convert(im, src);
247 =item i_destroy_p(i_img *im)
249 Destroys data related to a paletted image.
253 static void i_destroy_p(i_img *im) {
255 i_img_pal_ext *palext = im->ext_data;
265 =item i_ppix_p(i_img *im, int x, int y, i_color *val)
267 Write to a pixel in the image.
269 Warning: converts the image to a RGB image if the color isn't already
270 present in the image.
274 static int i_ppix_p(i_img *im, int x, int y, i_color *val) {
276 if (x < 0 || x >= im->xsize || y < 0 || y >= im->ysize)
278 if (i_findcolor(im, val, &which)) {
279 ((i_palidx *)im->idata)[x + y * im->xsize] = which;
283 if (i_img_to_rgb_inplace(im)) {
284 return i_ppix(im, x, y, val);
292 =item i_gpix(i_img *im, int x, int y, i_color *val)
294 Retrieve a pixel, converting from a palette index to a color.
298 static int i_gpix_p(i_img *im, int x, int y, i_color *val) {
300 if (x < 0 || x >= im->xsize || y < 0 || y >= im->ysize) {
303 which = ((i_palidx *)im->idata)[x + y * im->xsize];
304 if (which > PALEXT(im)->count)
306 *val = PALEXT(im)->pal[which];
312 =item i_glinp(i_img *im, int l, int r, int y, i_color *vals)
314 Retrieve a row of pixels.
318 static int i_glin_p(i_img *im, int l, int r, int y, i_color *vals) {
319 if (y >= 0 && y < im->ysize && l < im->xsize && l >= 0) {
320 int palsize = PALEXT(im)->count;
321 i_color *pal = PALEXT(im)->pal;
326 data = ((i_palidx *)im->idata) + l + y * im->xsize;
328 for (i = 0; i < count; ++i) {
329 i_palidx which = *data++;
331 vals[i] = pal[which];
341 =item i_plin_p(i_img *im, int l, int r, int y, i_color *vals)
343 Write a line of color data to the image.
345 If any color value is not in the image when the image is converted to
350 static int i_plin_p(i_img *im, int l, int r, int y, i_color *vals) {
354 if (y >=0 && y < im->ysize && l < im->xsize && l >= 0) {
357 data = ((i_palidx *)im->idata) + l + y * im->xsize;
359 for (i = 0; i < count; ++i) {
360 if (i_findcolor(im, vals+i, &which)) {
361 ((i_palidx *)data)[i] = which;
364 if (i_img_to_rgb_inplace(im)) {
365 return i+i_plin(im, l+i, r, y, vals+i);
377 =item i_gsamp_p(i_img *im, int l, int r, int y, i_sample_t *samps, int chans, int chan_count)
381 static int i_gsamp_p(i_img *im, int l, int r, int y, i_sample_t *samps,
382 int const *chans, int chan_count) {
384 if (y >= 0 && y < im->ysize && l < im->xsize && l >= 0) {
385 int palsize = PALEXT(im)->count;
386 i_color *pal = PALEXT(im)->pal;
391 data = ((i_palidx *)im->idata) + l + y * im->xsize;
395 for (ch = 0; ch < chan_count; ++ch) {
396 if (chans[ch] < 0 || chans[ch] >= im->channels) {
397 i_push_errorf(0, "No channel %d in this image", chans[ch]);
401 for (i = 0; i < w; ++i) {
402 i_palidx which = *data++;
403 if (which < palsize) {
404 for (ch = 0; ch < chan_count; ++ch) {
405 *samps++ = pal[which].channel[chans[ch]];
412 for (i = 0; i < w; ++i) {
413 i_palidx which = *data++;
414 if (which < palsize) {
415 for (ch = 0; ch < chan_count; ++ch) {
416 *samps++ = pal[which].channel[ch];
430 =item i_gpal_p(i_img *im, int l, int r, int y, i_palidx *vals)
435 static int i_gpal_p(i_img *im, int l, int r, int y, i_palidx *vals) {
436 if (y >= 0 && y < im->ysize && l < im->xsize && l >= 0) {
441 data = ((i_palidx *)im->idata) + l + y * im->xsize;
443 for (i = 0; i < w; ++i) {
454 =item i_ppal_p(i_img *im, int l, int r, int y, i_palidx *vals)
459 static int i_ppal_p(i_img *im, int l, int r, int y, i_palidx *vals) {
460 if (y >= 0 && y < im->ysize && l < im->xsize && l >= 0) {
465 data = ((i_palidx *)im->idata) + l + y * im->xsize;
467 for (i = 0; i < w; ++i) {
478 =item i_addcolors_p(i_img *im, i_color *color, int count)
482 static int i_addcolors_p(i_img *im, i_color *color, int count) {
483 if (PALEXT(im)->count + count <= PALEXT(im)->alloc) {
484 int result = PALEXT(im)->count;
487 PALEXT(im)->count += count;
489 PALEXT(im)->pal[index++] = *color++;
500 =item i_getcolors_p(i_img *im, int i, i_color *color, int count)
504 static int i_getcolors_p(i_img *im, int i, i_color *color, int count) {
505 if (i >= 0 && i+count <= PALEXT(im)->count) {
507 *color++ = PALEXT(im)->pal[i++];
516 static int color_eq(i_img *im, i_color *c1, i_color *c2) {
518 for (ch = 0; ch < im->channels; ++ch) {
519 if (c1->channel[ch] != c2->channel[ch])
526 =item i_colorcount_p(i_img *im)
530 static int i_colorcount_p(i_img *im) {
531 return PALEXT(im)->count;
535 =item i_maxcolors_p(i_img *im)
539 static int i_maxcolors_p(i_img *im) {
540 return PALEXT(im)->alloc;
544 =item i_setcolors_p(i_img *im, int index, i_color *colors, int count)
548 static int i_setcolors_p(i_img *im, int index, i_color *colors, int count) {
549 if (index >= 0 && count >= 1 && index + count <= PALEXT(im)->count) {
551 PALEXT(im)->pal[index++] = *colors++;
561 =item i_findcolor_p(i_img *im)
565 static int i_findcolor_p(i_img *im, i_color *color, i_palidx *entry) {
566 if (PALEXT(im)->count) {
568 /* often the same color comes up several times in a row */
569 if (PALEXT(im)->last_found >= 0) {
570 if (color_eq(im, color, PALEXT(im)->pal + PALEXT(im)->last_found)) {
571 *entry = PALEXT(im)->last_found;
575 for (i = 0; i < PALEXT(im)->count; ++i) {
576 if (color_eq(im, color, PALEXT(im)->pal + i)) {
577 PALEXT(im)->last_found = *entry = i;
590 Tony Cook <tony@develop-help.com>