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Diffstat (limited to 'jpeg/rdrle.c')
-rw-r--r-- | jpeg/rdrle.c | 387 |
1 files changed, 387 insertions, 0 deletions
diff --git a/jpeg/rdrle.c b/jpeg/rdrle.c new file mode 100644 index 0000000..542bc37 --- /dev/null +++ b/jpeg/rdrle.c @@ -0,0 +1,387 @@ +/* + * rdrle.c + * + * Copyright (C) 1991-1996, Thomas G. Lane. + * This file is part of the Independent JPEG Group's software. + * For conditions of distribution and use, see the accompanying README file. + * + * This file contains routines to read input images in Utah RLE format. + * The Utah Raster Toolkit library is required (version 3.1 or later). + * + * These routines may need modification for non-Unix environments or + * specialized applications. As they stand, they assume input from + * an ordinary stdio stream. They further assume that reading begins + * at the start of the file; start_input may need work if the + * user interface has already read some data (e.g., to determine that + * the file is indeed RLE format). + * + * Based on code contributed by Mike Lijewski, + * with updates from Robert Hutchinson. + */ + +#include "cdjpeg.h" /* Common decls for cjpeg/djpeg applications */ + +#ifdef RLE_SUPPORTED + +/* rle.h is provided by the Utah Raster Toolkit. */ + +#include <rle.h> + +/* + * We assume that JSAMPLE has the same representation as rle_pixel, + * to wit, "unsigned char". Hence we can't cope with 12- or 16-bit samples. + */ + +#if BITS_IN_JSAMPLE != 8 + Sorry, this code only copes with 8-bit JSAMPLEs. /* deliberate syntax err */ +#endif + +/* + * We support the following types of RLE files: + * + * GRAYSCALE - 8 bits, no colormap + * MAPPEDGRAY - 8 bits, 1 channel colomap + * PSEUDOCOLOR - 8 bits, 3 channel colormap + * TRUECOLOR - 24 bits, 3 channel colormap + * DIRECTCOLOR - 24 bits, no colormap + * + * For now, we ignore any alpha channel in the image. + */ + +typedef enum + { GRAYSCALE, MAPPEDGRAY, PSEUDOCOLOR, TRUECOLOR, DIRECTCOLOR } rle_kind; + + +/* + * Since RLE stores scanlines bottom-to-top, we have to invert the image + * to conform to JPEG's top-to-bottom order. To do this, we read the + * incoming image into a virtual array on the first get_pixel_rows call, + * then fetch the required row from the virtual array on subsequent calls. + */ + +typedef struct _rle_source_struct * rle_source_ptr; + +typedef struct _rle_source_struct { + struct cjpeg_source_struct pub; /* public fields */ + + rle_kind visual; /* actual type of input file */ + jvirt_sarray_ptr image; /* virtual array to hold the image */ + JDIMENSION row; /* current row # in the virtual array */ + rle_hdr header; /* Input file information */ + rle_pixel** rle_row; /* holds a row returned by rle_getrow() */ + +} rle_source_struct; + + +/* + * Read the file header; return image size and component count. + */ + +METHODDEF(void) +start_input_rle (j_compress_ptr cinfo, cjpeg_source_ptr sinfo) +{ + rle_source_ptr source = (rle_source_ptr) sinfo; + JDIMENSION width, height; +#ifdef PROGRESS_REPORT + cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress; +#endif + + /* Use RLE library routine to get the header info */ + source->header = *rle_hdr_init(NULL); + source->header.rle_file = source->pub.input_file; + switch (rle_get_setup(&(source->header))) { + case RLE_SUCCESS: + /* A-OK */ + break; + case RLE_NOT_RLE: + ERREXIT(cinfo, JERR_RLE_NOT); + break; + case RLE_NO_SPACE: + ERREXIT(cinfo, JERR_RLE_MEM); + break; + case RLE_EMPTY: + ERREXIT(cinfo, JERR_RLE_EMPTY); + break; + case RLE_EOF: + ERREXIT(cinfo, JERR_RLE_EOF); + break; + default: + ERREXIT(cinfo, JERR_RLE_BADERROR); + break; + } + + /* Figure out what we have, set private vars and return values accordingly */ + + width = source->header.xmax - source->header.xmin + 1; + height = source->header.ymax - source->header.ymin + 1; + source->header.xmin = 0; /* realign horizontally */ + source->header.xmax = width-1; + + cinfo->image_width = width; + cinfo->image_height = height; + cinfo->data_precision = 8; /* we can only handle 8 bit data */ + + if (source->header.ncolors == 1 && source->header.ncmap == 0) { + source->visual = GRAYSCALE; + TRACEMS2(cinfo, 1, JTRC_RLE_GRAY, width, height); + } else if (source->header.ncolors == 1 && source->header.ncmap == 1) { + source->visual = MAPPEDGRAY; + TRACEMS3(cinfo, 1, JTRC_RLE_MAPGRAY, width, height, + 1 << source->header.cmaplen); + } else if (source->header.ncolors == 1 && source->header.ncmap == 3) { + source->visual = PSEUDOCOLOR; + TRACEMS3(cinfo, 1, JTRC_RLE_MAPPED, width, height, + 1 << source->header.cmaplen); + } else if (source->header.ncolors == 3 && source->header.ncmap == 3) { + source->visual = TRUECOLOR; + TRACEMS3(cinfo, 1, JTRC_RLE_FULLMAP, width, height, + 1 << source->header.cmaplen); + } else if (source->header.ncolors == 3 && source->header.ncmap == 0) { + source->visual = DIRECTCOLOR; + TRACEMS2(cinfo, 1, JTRC_RLE, width, height); + } else + ERREXIT(cinfo, JERR_RLE_UNSUPPORTED); + + if (source->visual == GRAYSCALE || source->visual == MAPPEDGRAY) { + cinfo->in_color_space = JCS_GRAYSCALE; + cinfo->input_components = 1; + } else { + cinfo->in_color_space = JCS_RGB; + cinfo->input_components = 3; + } + + /* + * A place to hold each scanline while it's converted. + * (GRAYSCALE scanlines don't need converting) + */ + if (source->visual != GRAYSCALE) { + source->rle_row = (rle_pixel**) (*cinfo->mem->alloc_sarray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, + (JDIMENSION) width, (JDIMENSION) cinfo->input_components); + } + + /* request a virtual array to hold the image */ + source->image = (*cinfo->mem->request_virt_sarray) + ((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE, + (JDIMENSION) (width * source->header.ncolors), + (JDIMENSION) height, (JDIMENSION) 1); + +#ifdef PROGRESS_REPORT + if (progress != NULL) { + /* count file input as separate pass */ + progress->total_extra_passes++; + } +#endif + + source->pub.buffer_height = 1; +} + + +/* + * Read one row of pixels. + * Called only after load_image has read the image into the virtual array. + * Used for GRAYSCALE, MAPPEDGRAY, TRUECOLOR, and DIRECTCOLOR images. + */ + +METHODDEF(JDIMENSION) +get_rle_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo) +{ + rle_source_ptr source = (rle_source_ptr) sinfo; + + source->row--; + source->pub.buffer = (*cinfo->mem->access_virt_sarray) + ((j_common_ptr) cinfo, source->image, source->row, (JDIMENSION) 1, FALSE); + + return 1; +} + +/* + * Read one row of pixels. + * Called only after load_image has read the image into the virtual array. + * Used for PSEUDOCOLOR images. + */ + +METHODDEF(JDIMENSION) +get_pseudocolor_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo) +{ + rle_source_ptr source = (rle_source_ptr) sinfo; + JSAMPROW src_row, dest_row; + JDIMENSION col; + rle_map *colormap; + int val; + + colormap = source->header.cmap; + dest_row = source->pub.buffer[0]; + source->row--; + src_row = * (*cinfo->mem->access_virt_sarray) + ((j_common_ptr) cinfo, source->image, source->row, (JDIMENSION) 1, FALSE); + + for (col = cinfo->image_width; col > 0; col--) { + val = GETJSAMPLE(*src_row++); + *dest_row++ = (JSAMPLE) (colormap[val ] >> 8); + *dest_row++ = (JSAMPLE) (colormap[val + 256] >> 8); + *dest_row++ = (JSAMPLE) (colormap[val + 512] >> 8); + } + + return 1; +} + + +/* + * Load the image into a virtual array. We have to do this because RLE + * files start at the lower left while the JPEG standard has them starting + * in the upper left. This is called the first time we want to get a row + * of input. What we do is load the RLE data into the array and then call + * the appropriate routine to read one row from the array. Before returning, + * we set source->pub.get_pixel_rows so that subsequent calls go straight to + * the appropriate row-reading routine. + */ + +METHODDEF(JDIMENSION) +load_image (j_compress_ptr cinfo, cjpeg_source_ptr sinfo) +{ + rle_source_ptr source = (rle_source_ptr) sinfo; + JDIMENSION row, col; + JSAMPROW scanline, red_ptr, green_ptr, blue_ptr; + rle_pixel **rle_row; + rle_map *colormap; + char channel; +#ifdef PROGRESS_REPORT + cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress; +#endif + + colormap = source->header.cmap; + rle_row = source->rle_row; + + /* Read the RLE data into our virtual array. + * We assume here that (a) rle_pixel is represented the same as JSAMPLE, + * and (b) we are not on a machine where FAR pointers differ from regular. + */ + RLE_CLR_BIT(source->header, RLE_ALPHA); /* don't read the alpha channel */ + +#ifdef PROGRESS_REPORT + if (progress != NULL) { + progress->pub.pass_limit = cinfo->image_height; + progress->pub.pass_counter = 0; + (*progress->pub.progress_monitor) ((j_common_ptr) cinfo); + } +#endif + + switch (source->visual) { + + case GRAYSCALE: + case PSEUDOCOLOR: + for (row = 0; row < cinfo->image_height; row++) { + rle_row = (rle_pixel **) (*cinfo->mem->access_virt_sarray) + ((j_common_ptr) cinfo, source->image, row, (JDIMENSION) 1, TRUE); + rle_getrow(&source->header, rle_row); +#ifdef PROGRESS_REPORT + if (progress != NULL) { + progress->pub.pass_counter++; + (*progress->pub.progress_monitor) ((j_common_ptr) cinfo); + } +#endif + } + break; + + case MAPPEDGRAY: + case TRUECOLOR: + for (row = 0; row < cinfo->image_height; row++) { + scanline = * (*cinfo->mem->access_virt_sarray) + ((j_common_ptr) cinfo, source->image, row, (JDIMENSION) 1, TRUE); + rle_row = source->rle_row; + rle_getrow(&source->header, rle_row); + + for (col = 0; col < cinfo->image_width; col++) { + for (channel = 0; channel < source->header.ncolors; channel++) { + *scanline++ = (JSAMPLE) + (colormap[GETJSAMPLE(rle_row[channel][col]) + 256 * channel] >> 8); + } + } + +#ifdef PROGRESS_REPORT + if (progress != NULL) { + progress->pub.pass_counter++; + (*progress->pub.progress_monitor) ((j_common_ptr) cinfo); + } +#endif + } + break; + + case DIRECTCOLOR: + for (row = 0; row < cinfo->image_height; row++) { + scanline = * (*cinfo->mem->access_virt_sarray) + ((j_common_ptr) cinfo, source->image, row, (JDIMENSION) 1, TRUE); + rle_getrow(&source->header, rle_row); + + red_ptr = rle_row[0]; + green_ptr = rle_row[1]; + blue_ptr = rle_row[2]; + + for (col = cinfo->image_width; col > 0; col--) { + *scanline++ = *red_ptr++; + *scanline++ = *green_ptr++; + *scanline++ = *blue_ptr++; + } + +#ifdef PROGRESS_REPORT + if (progress != NULL) { + progress->pub.pass_counter++; + (*progress->pub.progress_monitor) ((j_common_ptr) cinfo); + } +#endif + } + } + +#ifdef PROGRESS_REPORT + if (progress != NULL) + progress->completed_extra_passes++; +#endif + + /* Set up to call proper row-extraction routine in future */ + if (source->visual == PSEUDOCOLOR) { + source->pub.buffer = source->rle_row; + source->pub.get_pixel_rows = get_pseudocolor_row; + } else { + source->pub.get_pixel_rows = get_rle_row; + } + source->row = cinfo->image_height; + + /* And fetch the topmost (bottommost) row */ + return (*source->pub.get_pixel_rows) (cinfo, sinfo); +} + + +/* + * Finish up at the end of the file. + */ + +METHODDEF(void) +finish_input_rle (j_compress_ptr cinfo, cjpeg_source_ptr sinfo) +{ + /* no work */ +} + + +/* + * The module selection routine for RLE format input. + */ + +GLOBAL(cjpeg_source_ptr) +jinit_read_rle (j_compress_ptr cinfo) +{ + rle_source_ptr source; + + /* Create module interface object */ + source = (rle_source_ptr) + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, + SIZEOF(rle_source_struct)); + /* Fill in method ptrs */ + source->pub.start_input = start_input_rle; + source->pub.finish_input = finish_input_rle; + source->pub.get_pixel_rows = load_image; + + return (cjpeg_source_ptr) source; +} + +#endif /* RLE_SUPPORTED */ |