1 /* 2 * wrrle.c 3 * 4 * This file was part of the Independent JPEG Group's software: 5 * Copyright (C) 1991-1996, Thomas G. Lane. 6 * It was modified by The libjpeg-turbo Project to include only code and 7 * information relevant to libjpeg-turbo. 8 * For conditions of distribution and use, see the accompanying README.ijg 9 * file. 10 * 11 * This file contains routines to write output images in RLE format. 12 * The Utah Raster Toolkit library is required (version 3.1 or later). 13 * 14 * These routines may need modification for non-Unix environments or 15 * specialized applications. As they stand, they assume output to 16 * an ordinary stdio stream. 17 * 18 * Based on code contributed by Mike Lijewski, 19 * with updates from Robert Hutchinson. 20 */ 21 22 #include "cdjpeg.h" /* Common decls for cjpeg/djpeg applications */ 23 24 #ifdef RLE_SUPPORTED 25 26 /* rle.h is provided by the Utah Raster Toolkit. */ 27 28 #include <rle.h> 29 30 /* 31 * We assume that JSAMPLE has the same representation as rle_pixel, 32 * to wit, "unsigned char". Hence we can't cope with 12- or 16-bit samples. 33 */ 34 35 #if BITS_IN_JSAMPLE != 8 36 Sorry, this code only copes with 8-bit JSAMPLEs. /* deliberate syntax err */ 37 #endif 38 39 40 /* 41 * Since RLE stores scanlines bottom-to-top, we have to invert the image 42 * from JPEG's top-to-bottom order. To do this, we save the outgoing data 43 * in a virtual array during put_pixel_row calls, then actually emit the 44 * RLE file during finish_output. 45 */ 46 47 48 /* 49 * For now, if we emit an RLE color map then it is always 256 entries long, 50 * though not all of the entries need be used. 51 */ 52 53 #define CMAPBITS 8 54 #define CMAPLENGTH (1<<(CMAPBITS)) 55 56 typedef struct { 57 struct djpeg_dest_struct pub; /* public fields */ 58 59 jvirt_sarray_ptr image; /* virtual array to store the output image */ 60 rle_map *colormap; /* RLE-style color map, or NULL if none */ 61 rle_pixel **rle_row; /* To pass rows to rle_putrow() */ 62 63 } rle_dest_struct; 64 65 typedef rle_dest_struct *rle_dest_ptr; 66 67 /* Forward declarations */ 68 METHODDEF(void) rle_put_pixel_rows 69 (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo, 70 JDIMENSION rows_supplied); 71 72 73 /* 74 * Write the file header. 75 * 76 * In this module it's easier to wait till finish_output to write anything. 77 */ 78 79 METHODDEF(void) 80 start_output_rle (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo) 81 { 82 rle_dest_ptr dest = (rle_dest_ptr) dinfo; 83 size_t cmapsize; 84 int i, ci; 85 #ifdef PROGRESS_REPORT 86 cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress; 87 #endif 88 89 /* 90 * Make sure the image can be stored in RLE format. 91 * 92 * - RLE stores image dimensions as *signed* 16 bit integers. JPEG 93 * uses unsigned, so we have to check the width. 94 * 95 * - Colorspace is expected to be grayscale or RGB. 96 * 97 * - The number of channels (components) is expected to be 1 (grayscale/ 98 * pseudocolor) or 3 (truecolor/directcolor). 99 * (could be 2 or 4 if using an alpha channel, but we aren't) 100 */ 101 102 if (cinfo->output_width > 32767 || cinfo->output_height > 32767) 103 ERREXIT2(cinfo, JERR_RLE_DIMENSIONS, cinfo->output_width, 104 cinfo->output_height); 105 106 if (cinfo->out_color_space != JCS_GRAYSCALE && 107 cinfo->out_color_space != JCS_RGB) 108 ERREXIT(cinfo, JERR_RLE_COLORSPACE); 109 110 if (cinfo->output_components != 1 && cinfo->output_components != 3) 111 ERREXIT1(cinfo, JERR_RLE_TOOMANYCHANNELS, cinfo->num_components); 112 113 /* Convert colormap, if any, to RLE format. */ 114 115 dest->colormap = NULL; 116 117 if (cinfo->quantize_colors) { 118 /* Allocate storage for RLE-style cmap, zero any extra entries */ 119 cmapsize = cinfo->out_color_components * CMAPLENGTH * sizeof(rle_map); 120 dest->colormap = (rle_map *) (*cinfo->mem->alloc_small) 121 ((j_common_ptr) cinfo, JPOOL_IMAGE, cmapsize); 122 MEMZERO(dest->colormap, cmapsize); 123 124 /* Save away data in RLE format --- note 8-bit left shift! */ 125 /* Shifting would need adjustment for JSAMPLEs wider than 8 bits. */ 126 for (ci = 0; ci < cinfo->out_color_components; ci++) { 127 for (i = 0; i < cinfo->actual_number_of_colors; i++) { 128 dest->colormap[ci * CMAPLENGTH + i] = 129 GETJSAMPLE(cinfo->colormap[ci][i]) << 8; 130 } 131 } 132 } 133 134 /* Set the output buffer to the first row */ 135 dest->pub.buffer = (*cinfo->mem->access_virt_sarray) 136 ((j_common_ptr) cinfo, dest->image, (JDIMENSION) 0, (JDIMENSION) 1, TRUE); 137 dest->pub.buffer_height = 1; 138 139 dest->pub.put_pixel_rows = rle_put_pixel_rows; 140 141 #ifdef PROGRESS_REPORT 142 if (progress != NULL) { 143 progress->total_extra_passes++; /* count file writing as separate pass */ 144 } 145 #endif 146 } 147 148 149 /* 150 * Write some pixel data. 151 * 152 * This routine just saves the data away in a virtual array. 153 */ 154 155 METHODDEF(void) 156 rle_put_pixel_rows (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo, 157 JDIMENSION rows_supplied) 158 { 159 rle_dest_ptr dest = (rle_dest_ptr) dinfo; 160 161 if (cinfo->output_scanline < cinfo->output_height) { 162 dest->pub.buffer = (*cinfo->mem->access_virt_sarray) 163 ((j_common_ptr) cinfo, dest->image, 164 cinfo->output_scanline, (JDIMENSION) 1, TRUE); 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, *green, *blue; 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 rle_pixel is represented the same as JSAMPLE. 214 */ 215 216 #ifdef PROGRESS_REPORT 217 if (progress != NULL) { 218 progress->pub.pass_limit = cinfo->output_height; 219 progress->pub.pass_counter = 0; 220 (*progress->pub.progress_monitor) ((j_common_ptr) cinfo); 221 } 222 #endif 223 224 if (cinfo->output_components == 1) { 225 for (row = cinfo->output_height-1; row >= 0; row--) { 226 rle_row = (rle_pixel **) (*cinfo->mem->access_virt_sarray) 227 ((j_common_ptr) cinfo, dest->image, 228 (JDIMENSION) row, (JDIMENSION) 1, FALSE); 229 rle_putrow(rle_row, (int) cinfo->output_width, &header); 230 #ifdef PROGRESS_REPORT 231 if (progress != NULL) { 232 progress->pub.pass_counter++; 233 (*progress->pub.progress_monitor) ((j_common_ptr) cinfo); 234 } 235 #endif 236 } 237 } else { 238 for (row = cinfo->output_height-1; row >= 0; row--) { 239 rle_row = (rle_pixel **) dest->rle_row; 240 output_row = *(*cinfo->mem->access_virt_sarray) 241 ((j_common_ptr) cinfo, dest->image, 242 (JDIMENSION) row, (JDIMENSION) 1, FALSE); 243 red = rle_row[0]; 244 green = rle_row[1]; 245 blue = rle_row[2]; 246 for (col = cinfo->output_width; col > 0; col--) { 247 *red++ = GETJSAMPLE(*output_row++); 248 *green++ = GETJSAMPLE(*output_row++); 249 *blue++ = GETJSAMPLE(*output_row++); 250 } 251 rle_putrow(rle_row, (int) cinfo->output_width, &header); 252 #ifdef PROGRESS_REPORT 253 if (progress != NULL) { 254 progress->pub.pass_counter++; 255 (*progress->pub.progress_monitor) ((j_common_ptr) cinfo); 256 } 257 #endif 258 } 259 } 260 261 #ifdef PROGRESS_REPORT 262 if (progress != NULL) 263 progress->completed_extra_passes++; 264 #endif 265 266 /* Emit file trailer */ 267 rle_puteof(&header); 268 fflush(dest->pub.output_file); 269 if (ferror(dest->pub.output_file)) 270 ERREXIT(cinfo, JERR_FILE_WRITE); 271 } 272 273 274 /* 275 * The module selection routine for RLE format output. 276 */ 277 278 GLOBAL(djpeg_dest_ptr) 279 jinit_write_rle (j_decompress_ptr cinfo) 280 { 281 rle_dest_ptr dest; 282 283 /* Create module interface object, fill in method pointers */ 284 dest = (rle_dest_ptr) 285 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, 286 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) 295 ((j_common_ptr) cinfo, JPOOL_IMAGE, 296 cinfo->output_width, (JDIMENSION) cinfo->output_components); 297 298 /* Allocate a virtual array to hold the image. */ 299 dest->image = (*cinfo->mem->request_virt_sarray) 300 ((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE, 301 (JDIMENSION) (cinfo->output_width * cinfo->output_components), 302 cinfo->output_height, (JDIMENSION) 1); 303 304 return (djpeg_dest_ptr) dest; 305 } 306 307 #endif /* RLE_SUPPORTED */ 308