+++ /dev/null
-/*
- * rdbmp.c
- *
- * Copyright (C) 1994-1996, 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 Microsoft "BMP"
- * format (MS Windows 3.x, OS/2 1.x, and OS/2 2.x flavors).
- * Currently, only 8-bit and 24-bit images are supported, not 1-bit or
- * 4-bit (feeding such low-depth images into JPEG would be silly anyway).
- * Also, we don't support RLE-compressed files.
- *
- * 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 BMP format).
- *
- * This code contributed by James Arthur Boucher.
- */
-
-#include "cdjpeg.h" /* Common decls for cjpeg/djpeg applications */
-
-#ifdef BMP_SUPPORTED
-
-
-/* Macros to deal with unsigned chars as efficiently as compiler allows */
-
-#ifdef HAVE_UNSIGNED_CHAR
-typedef unsigned char U_CHAR;
-#define UCH(x) ((int) (x))
-#else /* !HAVE_UNSIGNED_CHAR */
-#ifdef CHAR_IS_UNSIGNED
-typedef char U_CHAR;
-#define UCH(x) ((int) (x))
-#else
-typedef char U_CHAR;
-#define UCH(x) ((int) (x) & 0xFF)
-#endif
-#endif /* HAVE_UNSIGNED_CHAR */
-
-
-#define ReadOK(file,buffer,len) (JFREAD(file,buffer,len) == ((size_t) (len)))
-
-
-/* Private version of data source object */
-
-typedef struct _bmp_source_struct * bmp_source_ptr;
-
-typedef struct _bmp_source_struct {
- struct cjpeg_source_struct pub; /* public fields */
-
- j_compress_ptr cinfo; /* back link saves passing separate parm */
-
- JSAMPARRAY colormap; /* BMP colormap (converted to my format) */
-
- jvirt_sarray_ptr whole_image; /* Needed to reverse row order */
- JDIMENSION source_row; /* Current source row number */
- JDIMENSION row_width; /* Physical width of scanlines in file */
-
- int bits_per_pixel; /* remembers 8- or 24-bit format */
-} bmp_source_struct;
-
-
-LOCAL(int)
-read_byte (bmp_source_ptr sinfo)
-/* Read next byte from BMP file */
-{
- register FILE *infile = sinfo->pub.input_file;
- register int c;
-
- if ((c = getc(infile)) == EOF)
- ERREXIT(sinfo->cinfo, JERR_INPUT_EOF);
- return c;
-}
-
-
-LOCAL(void)
-read_colormap (bmp_source_ptr sinfo, int cmaplen, int mapentrysize)
-/* Read the colormap from a BMP file */
-{
- int i;
-
- switch (mapentrysize) {
- case 3:
- /* BGR format (occurs in OS/2 files) */
- for (i = 0; i < cmaplen; i++) {
- sinfo->colormap[2][i] = (JSAMPLE) read_byte(sinfo);
- sinfo->colormap[1][i] = (JSAMPLE) read_byte(sinfo);
- sinfo->colormap[0][i] = (JSAMPLE) read_byte(sinfo);
- }
- break;
- case 4:
- /* BGR0 format (occurs in MS Windows files) */
- for (i = 0; i < cmaplen; i++) {
- sinfo->colormap[2][i] = (JSAMPLE) read_byte(sinfo);
- sinfo->colormap[1][i] = (JSAMPLE) read_byte(sinfo);
- sinfo->colormap[0][i] = (JSAMPLE) read_byte(sinfo);
- (void) read_byte(sinfo);
- }
- break;
- default:
- ERREXIT(sinfo->cinfo, JERR_BMP_BADCMAP);
- break;
- }
-}
-
-
-/*
- * Read one row of pixels.
- * The image has been read into the whole_image array, but is otherwise
- * unprocessed. We must read it out in top-to-bottom row order, and if
- * it is an 8-bit image, we must expand colormapped pixels to 24bit format.
- */
-
-METHODDEF(JDIMENSION)
-get_8bit_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
-/* This version is for reading 8-bit colormap indexes */
-{
- bmp_source_ptr source = (bmp_source_ptr) sinfo;
- register JSAMPARRAY colormap = source->colormap;
- JSAMPARRAY image_ptr;
- register int t;
- register JSAMPROW inptr, outptr;
- register JDIMENSION col;
-
- /* Fetch next row from virtual array */
- source->source_row--;
- image_ptr = (*cinfo->mem->access_virt_sarray)
- ((j_common_ptr) cinfo, source->whole_image,
- source->source_row, (JDIMENSION) 1, FALSE);
-
- /* Expand the colormap indexes to real data */
- inptr = image_ptr[0];
- outptr = source->pub.buffer[0];
- for (col = cinfo->image_width; col > 0; col--) {
- t = GETJSAMPLE(*inptr++);
- *outptr++ = colormap[0][t]; /* can omit GETJSAMPLE() safely */
- *outptr++ = colormap[1][t];
- *outptr++ = colormap[2][t];
- }
-
- return 1;
-}
-
-
-METHODDEF(JDIMENSION)
-get_24bit_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
-/* This version is for reading 24-bit pixels */
-{
- bmp_source_ptr source = (bmp_source_ptr) sinfo;
- JSAMPARRAY image_ptr;
- register JSAMPROW inptr, outptr;
- register JDIMENSION col;
-
- /* Fetch next row from virtual array */
- source->source_row--;
- image_ptr = (*cinfo->mem->access_virt_sarray)
- ((j_common_ptr) cinfo, source->whole_image,
- source->source_row, (JDIMENSION) 1, FALSE);
-
- /* Transfer data. Note source values are in BGR order
- * (even though Microsoft's own documents say the opposite).
- */
- inptr = image_ptr[0];
- outptr = source->pub.buffer[0];
- for (col = cinfo->image_width; col > 0; col--) {
- outptr[2] = *inptr++; /* can omit GETJSAMPLE() safely */
- outptr[1] = *inptr++;
- outptr[0] = *inptr++;
- outptr += 3;
- }
-
- return 1;
-}
-
-
-/*
- * This method loads the image into whole_image during the first call on
- * get_pixel_rows. The get_pixel_rows pointer is then adjusted to call
- * get_8bit_row or get_24bit_row on subsequent calls.
- */
-
-METHODDEF(JDIMENSION)
-preload_image (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
-{
- bmp_source_ptr source = (bmp_source_ptr) sinfo;
- register FILE *infile = source->pub.input_file;
- register int c;
- register JSAMPROW out_ptr;
- JSAMPARRAY image_ptr;
- JDIMENSION row, col;
- cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress;
-
- /* Read the data into a virtual array in input-file row order. */
- for (row = 0; row < cinfo->image_height; row++) {
- if (progress != NULL) {
- progress->pub.pass_counter = (long) row;
- progress->pub.pass_limit = (long) cinfo->image_height;
- (*progress->pub.progress_monitor) ((j_common_ptr) cinfo);
- }
- image_ptr = (*cinfo->mem->access_virt_sarray)
- ((j_common_ptr) cinfo, source->whole_image,
- row, (JDIMENSION) 1, TRUE);
- out_ptr = image_ptr[0];
- for (col = source->row_width; col > 0; col--) {
- /* inline copy of read_byte() for speed */
- if ((c = getc(infile)) == EOF)
- ERREXIT(cinfo, JERR_INPUT_EOF);
- *out_ptr++ = (JSAMPLE) c;
- }
- }
- if (progress != NULL)
- progress->completed_extra_passes++;
-
- /* Set up to read from the virtual array in top-to-bottom order */
- switch (source->bits_per_pixel) {
- case 8:
- source->pub.get_pixel_rows = get_8bit_row;
- break;
- case 24:
- source->pub.get_pixel_rows = get_24bit_row;
- break;
- default:
- ERREXIT(cinfo, JERR_BMP_BADDEPTH);
- }
- source->source_row = cinfo->image_height;
-
- /* And read the first row */
- return (*source->pub.get_pixel_rows) (cinfo, sinfo);
-}
-
-
-/*
- * Read the file header; return image size and component count.
- */
-
-METHODDEF(void)
-start_input_bmp (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
-{
- bmp_source_ptr source = (bmp_source_ptr) sinfo;
- U_CHAR bmpfileheader[14];
- U_CHAR bmpinfoheader[64];
-#define GET_2B(array,offset) ((unsigned int) UCH(array[offset]) + \
- (((unsigned int) UCH(array[offset+1])) << 8))
-#define GET_4B(array,offset) ((INT32) UCH(array[offset]) + \
- (((INT32) UCH(array[offset+1])) << 8) + \
- (((INT32) UCH(array[offset+2])) << 16) + \
- (((INT32) UCH(array[offset+3])) << 24))
- INT32 bfOffBits;
- INT32 headerSize;
- INT32 biWidth = 0; /* initialize to avoid compiler warning */
- INT32 biHeight = 0;
- unsigned int biPlanes;
- INT32 biCompression;
- INT32 biXPelsPerMeter,biYPelsPerMeter;
- INT32 biClrUsed = 0;
- int mapentrysize = 0; /* 0 indicates no colormap */
- INT32 bPad;
- JDIMENSION row_width;
-
- /* Read and verify the bitmap file header */
- if (! ReadOK(source->pub.input_file, bmpfileheader, 14))
- ERREXIT(cinfo, JERR_INPUT_EOF);
- if (GET_2B(bmpfileheader,0) != 0x4D42) /* 'BM' */
- ERREXIT(cinfo, JERR_BMP_NOT);
- bfOffBits = (INT32) GET_4B(bmpfileheader,10);
- /* We ignore the remaining fileheader fields */
-
- /* The infoheader might be 12 bytes (OS/2 1.x), 40 bytes (Windows),
- * or 64 bytes (OS/2 2.x). Check the first 4 bytes to find out which.
- */
- if (! ReadOK(source->pub.input_file, bmpinfoheader, 4))
- ERREXIT(cinfo, JERR_INPUT_EOF);
- headerSize = (INT32) GET_4B(bmpinfoheader,0);
- if (headerSize < 12 || headerSize > 64)
- ERREXIT(cinfo, JERR_BMP_BADHEADER);
- if (! ReadOK(source->pub.input_file, bmpinfoheader+4, headerSize-4))
- ERREXIT(cinfo, JERR_INPUT_EOF);
-
- switch ((int) headerSize) {
- case 12:
- /* Decode OS/2 1.x header (Microsoft calls this a BITMAPCOREHEADER) */
- biWidth = (INT32) GET_2B(bmpinfoheader,4);
- biHeight = (INT32) GET_2B(bmpinfoheader,6);
- biPlanes = GET_2B(bmpinfoheader,8);
- source->bits_per_pixel = (int) GET_2B(bmpinfoheader,10);
-
- switch (source->bits_per_pixel) {
- case 8: /* colormapped image */
- mapentrysize = 3; /* OS/2 uses RGBTRIPLE colormap */
- TRACEMS2(cinfo, 1, JTRC_BMP_OS2_MAPPED, (int) biWidth, (int) biHeight);
- break;
- case 24: /* RGB image */
- TRACEMS2(cinfo, 1, JTRC_BMP_OS2, (int) biWidth, (int) biHeight);
- break;
- default:
- ERREXIT(cinfo, JERR_BMP_BADDEPTH);
- break;
- }
- if (biPlanes != 1)
- ERREXIT(cinfo, JERR_BMP_BADPLANES);
- break;
- case 40:
- case 64:
- /* Decode Windows 3.x header (Microsoft calls this a BITMAPINFOHEADER) */
- /* or OS/2 2.x header, which has additional fields that we ignore */
- biWidth = GET_4B(bmpinfoheader,4);
- biHeight = GET_4B(bmpinfoheader,8);
- biPlanes = GET_2B(bmpinfoheader,12);
- source->bits_per_pixel = (int) GET_2B(bmpinfoheader,14);
- biCompression = GET_4B(bmpinfoheader,16);
- biXPelsPerMeter = GET_4B(bmpinfoheader,24);
- biYPelsPerMeter = GET_4B(bmpinfoheader,28);
- biClrUsed = GET_4B(bmpinfoheader,32);
- /* biSizeImage, biClrImportant fields are ignored */
-
- switch (source->bits_per_pixel) {
- case 8: /* colormapped image */
- mapentrysize = 4; /* Windows uses RGBQUAD colormap */
- TRACEMS2(cinfo, 1, JTRC_BMP_MAPPED, (int) biWidth, (int) biHeight);
- break;
- case 24: /* RGB image */
- TRACEMS2(cinfo, 1, JTRC_BMP, (int) biWidth, (int) biHeight);
- break;
- default:
- ERREXIT(cinfo, JERR_BMP_BADDEPTH);
- break;
- }
- if (biPlanes != 1)
- ERREXIT(cinfo, JERR_BMP_BADPLANES);
- if (biCompression != 0)
- ERREXIT(cinfo, JERR_BMP_COMPRESSED);
-
- if (biXPelsPerMeter > 0 && biYPelsPerMeter > 0) {
- /* Set JFIF density parameters from the BMP data */
- cinfo->X_density = (UINT16) (biXPelsPerMeter/100); /* 100 cm per meter */
- cinfo->Y_density = (UINT16) (biYPelsPerMeter/100);
- cinfo->density_unit = 2; /* dots/cm */
- }
- break;
- default:
- ERREXIT(cinfo, JERR_BMP_BADHEADER);
- break;
- }
-
- /* Compute distance to bitmap data --- will adjust for colormap below */
- bPad = bfOffBits - (headerSize + 14);
-
- /* Read the colormap, if any */
- if (mapentrysize > 0) {
- if (biClrUsed <= 0)
- biClrUsed = 256; /* assume it's 256 */
- else if (biClrUsed > 256)
- ERREXIT(cinfo, JERR_BMP_BADCMAP);
- /* Allocate space to store the colormap */
- source->colormap = (*cinfo->mem->alloc_sarray)
- ((j_common_ptr) cinfo, JPOOL_IMAGE,
- (JDIMENSION) biClrUsed, (JDIMENSION) 3);
- /* and read it from the file */
- read_colormap(source, (int) biClrUsed, mapentrysize);
- /* account for size of colormap */
- bPad -= biClrUsed * mapentrysize;
- }
-
- /* Skip any remaining pad bytes */
- if (bPad < 0) /* incorrect bfOffBits value? */
- ERREXIT(cinfo, JERR_BMP_BADHEADER);
- while (--bPad >= 0) {
- (void) read_byte(source);
- }
-
- /* Compute row width in file, including padding to 4-byte boundary */
- if (source->bits_per_pixel == 24)
- row_width = (JDIMENSION) (biWidth * 3);
- else
- row_width = (JDIMENSION) biWidth;
- while ((row_width & 3) != 0) row_width++;
- source->row_width = row_width;
-
- /* Allocate space for inversion array, prepare for preload pass */
- source->whole_image = (*cinfo->mem->request_virt_sarray)
- ((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE,
- row_width, (JDIMENSION) biHeight, (JDIMENSION) 1);
- source->pub.get_pixel_rows = preload_image;
- if (cinfo->progress != NULL) {
- cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress;
- progress->total_extra_passes++; /* count file input as separate pass */
- }
-
- /* Allocate one-row buffer for returned data */
- source->pub.buffer = (*cinfo->mem->alloc_sarray)
- ((j_common_ptr) cinfo, JPOOL_IMAGE,
- (JDIMENSION) (biWidth * 3), (JDIMENSION) 1);
- source->pub.buffer_height = 1;
-
- cinfo->in_color_space = JCS_RGB;
- cinfo->input_components = 3;
- cinfo->data_precision = 8;
- cinfo->image_width = (JDIMENSION) biWidth;
- cinfo->image_height = (JDIMENSION) biHeight;
-}
-
-
-/*
- * Finish up at the end of the file.
- */
-
-METHODDEF(void)
-finish_input_bmp (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
-{
- /* no work */
-}
-
-
-/*
- * The module selection routine for BMP format input.
- */
-
-GLOBAL(cjpeg_source_ptr)
-jinit_read_bmp (j_compress_ptr cinfo)
-{
- bmp_source_ptr source;
-
- /* Create module interface object */
- source = (bmp_source_ptr)
- (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
- SIZEOF(bmp_source_struct));
- source->cinfo = cinfo; /* make back link for subroutines */
- /* Fill in method ptrs, except get_pixel_rows which start_input sets */
- source->pub.start_input = start_input_bmp;
- source->pub.finish_input = finish_input_bmp;
-
- return (cjpeg_source_ptr) source;
-}
-
-#endif /* BMP_SUPPORTED */
projects / synfig.git / blobdiff