1 /*
2  * wrrle.c
3  *
4  * Copyright (C) 1991-1996, Thomas G. Lane.
5  * Modified 2017-2019 by Guido Vollbeding.
6  * This file is part of the Independent JPEG Group's software.
7  * For conditions of distribution and use, see the accompanying README file.
8  *
9  * This file contains routines to write output images in RLE format.
10  * The Utah Raster Toolkit library is required (version 3.1 or later).
11  *
12  * These routines may need modification for non-Unix environments or
13  * specialized applications.  As they stand, they assume output to
14  * an ordinary stdio stream.
15  *
16  * Based on code contributed by Mike Lijewski,
17  * with updates from Robert Hutchinson.
18  */
19 
20 #include "cdjpeg.h"		/* Common decls for cjpeg/djpeg applications */
21 
22 #ifdef RLE_SUPPORTED
23 
24 /* rle.h is provided by the Utah Raster Toolkit. */
25 
26 #include <rle.h>
27 
28 /*
29  * We assume that JSAMPLE has the same representation as rle_pixel,
30  * to wit, "unsigned char".  Hence we can't cope with 12- or 16-bit samples.
31  */
32 
33 #if BITS_IN_JSAMPLE != 8
34   Sorry, this code only copes with 8-bit JSAMPLEs. /* deliberate syntax err */
35 #endif
36 
37 
38 /*
39  * Since RLE stores scanlines bottom-to-top, we have to invert the image
40  * from JPEG's top-to-bottom order.  To do this, we save the outgoing data
41  * in a virtual array during put_pixel_row calls, then actually emit the
42  * RLE file during finish_output.
43  */
44 
45 
46 /*
47  * For now, if we emit an RLE color map then it is always 256 entries long,
48  * though not all of the entries need be used.
49  */
50 
51 #define CMAPBITS	8
52 #define CMAPLENGTH	(1<<(CMAPBITS))
53 
54 typedef struct {
55   struct djpeg_dest_struct pub; /* public fields */
56 
57   jvirt_sarray_ptr image;	/* virtual array to store the output image */
58   rle_map *colormap;	 	/* RLE-style color map, or NULL if none */
59   rle_pixel **rle_row;		/* To pass rows to rle_putrow() */
60 
61 } rle_dest_struct;
62 
63 typedef rle_dest_struct * rle_dest_ptr;
64 
65 
66 /* Forward declarations */
67 METHODDEF(void) rle_put_pixel_rows
68     JPP((j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
69 	 JDIMENSION rows_supplied));
70 
71 
72 /*
73  * Write the file header.
74  *
75  * In this module it's easier to wait till finish_output to write anything.
76  */
77 
78 METHODDEF(void)
start_output_rle(j_decompress_ptr cinfo,djpeg_dest_ptr dinfo)79 start_output_rle (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
80 {
81   rle_dest_ptr dest = (rle_dest_ptr) dinfo;
82   size_t cmapsize;
83   int ci, i;
84 #ifdef PROGRESS_REPORT
85   cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress;
86 #endif
87 
88   /*
89    * Make sure the image can be stored in RLE format.
90    *
91    * - RLE stores image dimensions as *signed* 16 bit integers.  JPEG
92    *   uses unsigned, so we have to check the width.
93    *
94    * - Colorspace is expected to be grayscale or RGB.
95    *
96    * - The number of channels (components) is expected to be 1 (grayscale/
97    *   pseudocolor) or 3 (truecolor/directcolor).
98    *   (could be 2 or 4 if using an alpha channel, but we aren't)
99    */
100 
101   if (cinfo->output_width > 32767 || cinfo->output_height > 32767)
102     ERREXIT2(cinfo, JERR_RLE_DIMENSIONS, cinfo->output_width,
103 	     cinfo->output_height);
104 
105   if (cinfo->out_color_space != JCS_GRAYSCALE &&
106       cinfo->out_color_space != JCS_RGB)
107     ERREXIT(cinfo, JERR_RLE_COLORSPACE);
108 
109   if (cinfo->output_components != 1 && cinfo->output_components != 3)
110     ERREXIT1(cinfo, JERR_RLE_TOOMANYCHANNELS, cinfo->num_components);
111 
112   /* Convert colormap, if any, to RLE format. */
113 
114   dest->colormap = NULL;
115 
116   if (cinfo->quantize_colors) {
117     /* Allocate storage for RLE-style cmap, zero any extra entries */
118     cmapsize = cinfo->out_color_components * CMAPLENGTH * SIZEOF(rle_map);
119     dest->colormap = (rle_map *) (*cinfo->mem->alloc_small)
120       ((j_common_ptr) cinfo, JPOOL_IMAGE, cmapsize);
121     MEMZERO(dest->colormap, cmapsize);
122 
123     /* Save away data in RLE format --- note 8-bit left shift! */
124     /* Shifting would need adjustment for JSAMPLEs wider than 8 bits. */
125     for (ci = 0; ci < cinfo->out_color_components; ci++) {
126       for (i = 0; i < cinfo->actual_number_of_colors; i++) {
127 	dest->colormap[ci * CMAPLENGTH + i] =
128 	  GETJSAMPLE(cinfo->colormap[ci][i]) << 8;
129       }
130     }
131   }
132 
133   /* Set the output buffer to the first row */
134   dest->pub.buffer = (*cinfo->mem->access_virt_sarray)
135     ((j_common_ptr) cinfo, dest->image, (JDIMENSION) 0, (JDIMENSION) 1, TRUE);
136   dest->pub.buffer_height = 1;
137 
138   dest->pub.put_pixel_rows = rle_put_pixel_rows;
139 
140 #ifdef PROGRESS_REPORT
141   if (progress != NULL) {
142     progress->total_extra_passes++;  /* count file writing as separate pass */
143   }
144 #endif
145 }
146 
147 
148 /*
149  * Write some pixel data.
150  *
151  * This routine just saves the data away in a virtual array.
152  */
153 
154 METHODDEF(void)
rle_put_pixel_rows(j_decompress_ptr cinfo,djpeg_dest_ptr dinfo,JDIMENSION rows_supplied)155 rle_put_pixel_rows (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
156 		    JDIMENSION rows_supplied)
157 {
158   rle_dest_ptr dest = (rle_dest_ptr) dinfo;
159 
160   if (cinfo->output_scanline < cinfo->output_height) {
161     dest->pub.buffer = (*cinfo->mem->access_virt_sarray)
162       ((j_common_ptr) cinfo, dest->image,
163        cinfo->output_scanline, (JDIMENSION) 1, TRUE);
164   }
165 }
166 
167 
168 /*
169  * Finish up at the end of the file.
170  *
171  * Here is where we really output the RLE file.
172  */
173 
174 METHODDEF(void)
finish_output_rle(j_decompress_ptr cinfo,djpeg_dest_ptr dinfo)175 finish_output_rle (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
176 {
177   rle_dest_ptr dest = (rle_dest_ptr) dinfo;
178   rle_hdr header;		/* Output file information */
179   rle_pixel **rle_row, *red_ptr, *green_ptr, *blue_ptr;
180   JSAMPROW output_row;
181   char cmapcomment[80];
182   int row, col;
183   int ci;
184 #ifdef PROGRESS_REPORT
185   cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress;
186 #endif
187 
188   /* Initialize the header info */
189   header = *rle_hdr_init(NULL);
190   header.rle_file = dest->pub.output_file;
191   header.xmin     = 0;
192   header.xmax     = cinfo->output_width  - 1;
193   header.ymin     = 0;
194   header.ymax     = cinfo->output_height - 1;
195   header.alpha    = 0;
196   header.ncolors  = cinfo->output_components;
197   for (ci = 0; ci < cinfo->output_components; ci++) {
198     RLE_SET_BIT(header, ci);
199   }
200   if (cinfo->quantize_colors) {
201     header.ncmap   = cinfo->out_color_components;
202     header.cmaplen = CMAPBITS;
203     header.cmap    = dest->colormap;
204     /* Add a comment to the output image with the true colormap length. */
205     sprintf(cmapcomment, "color_map_length=%d", cinfo->actual_number_of_colors);
206     rle_putcom(cmapcomment, &header);
207   }
208 
209   /* Emit the RLE header and color map (if any) */
210   rle_put_setup(&header);
211 
212   /* Now output the RLE data from our virtual array.
213    * We assume here that (a) rle_pixel is represented the same as JSAMPLE,
214    * and (b) we are not on a machine where FAR pointers differ from regular.
215    */
216 
217 #ifdef PROGRESS_REPORT
218   if (progress != NULL) {
219     progress->pub.pass_limit = cinfo->output_height;
220     progress->pub.pass_counter = 0;
221     (*progress->pub.progress_monitor) ((j_common_ptr) cinfo);
222   }
223 #endif
224 
225   if (cinfo->output_components == 1) {
226     for (row = cinfo->output_height - 1; row >= 0; row--) {
227       rle_row = (rle_pixel **) (*cinfo->mem->access_virt_sarray)
228 	((j_common_ptr) cinfo, dest->image,
229 	 (JDIMENSION) row, (JDIMENSION) 1, FALSE);
230       rle_putrow(rle_row, (int) cinfo->output_width, &header);
231 #ifdef PROGRESS_REPORT
232       if (progress != NULL) {
233 	progress->pub.pass_counter++;
234 	(*progress->pub.progress_monitor) ((j_common_ptr) cinfo);
235       }
236 #endif
237     }
238   } else {
239     for (row = cinfo->output_height - 1; row >= 0; row--) {
240       output_row = * (*cinfo->mem->access_virt_sarray)
241 	((j_common_ptr) cinfo, dest->image,
242 	 (JDIMENSION) row, (JDIMENSION) 1, FALSE);
243       rle_row = dest->rle_row;
244       red_ptr   = rle_row[0];
245       green_ptr = rle_row[1];
246       blue_ptr  = rle_row[2];
247       for (col = cinfo->output_width; col > 0; col--) {
248 	*red_ptr++   = GETJSAMPLE(*output_row++);
249 	*green_ptr++ = GETJSAMPLE(*output_row++);
250 	*blue_ptr++  = GETJSAMPLE(*output_row++);
251       }
252       rle_putrow(rle_row, (int) cinfo->output_width, &header);
253 #ifdef PROGRESS_REPORT
254       if (progress != NULL) {
255 	progress->pub.pass_counter++;
256 	(*progress->pub.progress_monitor) ((j_common_ptr) cinfo);
257       }
258 #endif
259     }
260   }
261 
262 #ifdef PROGRESS_REPORT
263   if (progress != NULL)
264     progress->completed_extra_passes++;
265 #endif
266 
267   /* Emit file trailer */
268   rle_puteof(&header);
269   JFFLUSH(dest->pub.output_file);
270   if (JFERROR(dest->pub.output_file))
271     ERREXIT(cinfo, JERR_FILE_WRITE);
272 }
273 
274 
275 /*
276  * The module selection routine for RLE format output.
277  */
278 
279 GLOBAL(djpeg_dest_ptr)
jinit_write_rle(j_decompress_ptr cinfo)280 jinit_write_rle (j_decompress_ptr cinfo)
281 {
282   rle_dest_ptr dest;
283 
284   /* Create module interface object, fill in method pointers */
285   dest = (rle_dest_ptr) (*cinfo->mem->alloc_small)
286     ((j_common_ptr) cinfo, JPOOL_IMAGE, SIZEOF(rle_dest_struct));
287   dest->pub.start_output = start_output_rle;
288   dest->pub.finish_output = finish_output_rle;
289 
290   /* Calculate output image dimensions so we can allocate space */
291   jpeg_calc_output_dimensions(cinfo);
292 
293   /* Allocate a work array for output to the RLE library. */
294   dest->rle_row = (*cinfo->mem->alloc_sarray) ((j_common_ptr) cinfo,
295     JPOOL_IMAGE, cinfo->output_width, (JDIMENSION) cinfo->output_components);
296 
297   /* Allocate a virtual array to hold the image. */
298   dest->image = (*cinfo->mem->request_virt_sarray)
299     ((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE,
300      cinfo->output_width * (JDIMENSION) cinfo->output_components,
301      cinfo->output_height, (JDIMENSION) 1);
302 
303   return &dest->pub;
304 }
305 
306 #endif /* RLE_SUPPORTED */
307