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