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) 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) 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) 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) 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