1 files changed, 500 insertions, 0 deletions

diff --git a/libjpegtwrp/rdtarga.c b/libjpegtwrp/rdtarga.c
new file mode 100644
index 000000000..4c2cd2673
--- /dev/null
+++ b/libjpegtwrp/rdtarga.c
@@ -0,0 +1,500 @@
+/*
+ * rdtarga.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 Targa format.
+ *
+ * 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 Targa format).
+ *
+ * Based on code contributed by Lee Daniel Crocker.
+ */
+
+#include "cdjpeg.h"		/* Common decls for cjpeg/djpeg applications */
+
+#ifdef TARGA_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 _tga_source_struct * tga_source_ptr;
+
+typedef struct _tga_source_struct {
+  struct cjpeg_source_struct pub; /* public fields */
+
+  j_compress_ptr cinfo;		/* back link saves passing separate parm */
+
+  JSAMPARRAY colormap;		/* Targa colormap (converted to my format) */
+
+  jvirt_sarray_ptr whole_image;	/* Needed if funny input row order */
+  JDIMENSION current_row;	/* Current logical row number to read */
+
+  /* Pointer to routine to extract next Targa pixel from input file */
+  JMETHOD(void, read_pixel, (tga_source_ptr sinfo));
+
+  /* Result of read_pixel is delivered here: */
+  U_CHAR tga_pixel[4];
+
+  int pixel_size;		/* Bytes per Targa pixel (1 to 4) */
+
+  /* State info for reading RLE-coded pixels; both counts must be init to 0 */
+  int block_count;		/* # of pixels remaining in RLE block */
+  int dup_pixel_count;		/* # of times to duplicate previous pixel */
+
+  /* This saves the correct pixel-row-expansion method for preload_image */
+  JMETHOD(JDIMENSION, get_pixel_rows, (j_compress_ptr cinfo,
+				       cjpeg_source_ptr sinfo));
+} tga_source_struct;
+
+
+/* For expanding 5-bit pixel values to 8-bit with best rounding */
+
+static const UINT8 c5to8bits[32] = {
+    0,   8,  16,  25,  33,  41,  49,  58,
+   66,  74,  82,  90,  99, 107, 115, 123,
+  132, 140, 148, 156, 165, 173, 181, 189,
+  197, 206, 214, 222, 230, 239, 247, 255
+};
+
+
+
+LOCAL(int)
+read_byte (tga_source_ptr sinfo)
+/* Read next byte from Targa 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 (tga_source_ptr sinfo, int cmaplen, int mapentrysize)
+/* Read the colormap from a Targa file */
+{
+  int i;
+
+  /* Presently only handles 24-bit BGR format */
+  if (mapentrysize != 24)
+    ERREXIT(sinfo->cinfo, JERR_TGA_BADCMAP);
+
+  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);
+  }
+}
+
+
+/*
+ * read_pixel methods: get a single pixel from Targa file into tga_pixel[]
+ */
+
+METHODDEF(void)
+read_non_rle_pixel (tga_source_ptr sinfo)
+/* Read one Targa pixel from the input file; no RLE expansion */
+{
+  register FILE *infile = sinfo->pub.input_file;
+  register int i;
+
+  for (i = 0; i < sinfo->pixel_size; i++) {
+    sinfo->tga_pixel[i] = (U_CHAR) getc(infile);
+  }
+}
+
+
+METHODDEF(void)
+read_rle_pixel (tga_source_ptr sinfo)
+/* Read one Targa pixel from the input file, expanding RLE data as needed */
+{
+  register FILE *infile = sinfo->pub.input_file;
+  register int i;
+
+  /* Duplicate previously read pixel? */
+  if (sinfo->dup_pixel_count > 0) {
+    sinfo->dup_pixel_count--;
+    return;
+  }
+
+  /* Time to read RLE block header? */
+  if (--sinfo->block_count < 0) { /* decrement pixels remaining in block */
+    i = read_byte(sinfo);
+    if (i & 0x80) {		/* Start of duplicate-pixel block? */
+      sinfo->dup_pixel_count = i & 0x7F; /* number of dups after this one */
+      sinfo->block_count = 0;	/* then read new block header */
+    } else {
+      sinfo->block_count = i & 0x7F; /* number of pixels after this one */
+    }
+  }
+
+  /* Read next pixel */
+  for (i = 0; i < sinfo->pixel_size; i++) {
+    sinfo->tga_pixel[i] = (U_CHAR) getc(infile);
+  }
+}
+
+
+/*
+ * Read one row of pixels.
+ *
+ * We provide several different versions depending on input file format.
+ */
+
+
+METHODDEF(JDIMENSION)
+get_8bit_gray_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
+/* This version is for reading 8-bit grayscale pixels */
+{
+  tga_source_ptr source = (tga_source_ptr) sinfo;
+  register JSAMPROW ptr;
+  register JDIMENSION col;
+  
+  ptr = source->pub.buffer[0];
+  for (col = cinfo->image_width; col > 0; col--) {
+    (*source->read_pixel) (source); /* Load next pixel into tga_pixel */
+    *ptr++ = (JSAMPLE) UCH(source->tga_pixel[0]);
+  }
+  return 1;
+}
+
+METHODDEF(JDIMENSION)
+get_8bit_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
+/* This version is for reading 8-bit colormap indexes */
+{
+  tga_source_ptr source = (tga_source_ptr) sinfo;
+  register int t;
+  register JSAMPROW ptr;
+  register JDIMENSION col;
+  register JSAMPARRAY colormap = source->colormap;
+
+  ptr = source->pub.buffer[0];
+  for (col = cinfo->image_width; col > 0; col--) {
+    (*source->read_pixel) (source); /* Load next pixel into tga_pixel */
+    t = UCH(source->tga_pixel[0]);
+    *ptr++ = colormap[0][t];
+    *ptr++ = colormap[1][t];
+    *ptr++ = colormap[2][t];
+  }
+  return 1;
+}
+
+METHODDEF(JDIMENSION)
+get_16bit_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
+/* This version is for reading 16-bit pixels */
+{
+  tga_source_ptr source = (tga_source_ptr) sinfo;
+  register int t;
+  register JSAMPROW ptr;
+  register JDIMENSION col;
+  
+  ptr = source->pub.buffer[0];
+  for (col = cinfo->image_width; col > 0; col--) {
+    (*source->read_pixel) (source); /* Load next pixel into tga_pixel */
+    t = UCH(source->tga_pixel[0]);
+    t += UCH(source->tga_pixel[1]) << 8;
+    /* We expand 5 bit data to 8 bit sample width.
+     * The format of the 16-bit (LSB first) input word is
+     *     xRRRRRGGGGGBBBBB
+     */
+    ptr[2] = (JSAMPLE) c5to8bits[t & 0x1F];
+    t >>= 5;
+    ptr[1] = (JSAMPLE) c5to8bits[t & 0x1F];
+    t >>= 5;
+    ptr[0] = (JSAMPLE) c5to8bits[t & 0x1F];
+    ptr += 3;
+  }
+  return 1;
+}
+
+METHODDEF(JDIMENSION)
+get_24bit_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
+/* This version is for reading 24-bit pixels */
+{
+  tga_source_ptr source = (tga_source_ptr) sinfo;
+  register JSAMPROW ptr;
+  register JDIMENSION col;
+  
+  ptr = source->pub.buffer[0];
+  for (col = cinfo->image_width; col > 0; col--) {
+    (*source->read_pixel) (source); /* Load next pixel into tga_pixel */
+    *ptr++ = (JSAMPLE) UCH(source->tga_pixel[2]); /* change BGR to RGB order */
+    *ptr++ = (JSAMPLE) UCH(source->tga_pixel[1]);
+    *ptr++ = (JSAMPLE) UCH(source->tga_pixel[0]);
+  }
+  return 1;
+}
+
+/*
+ * Targa also defines a 32-bit pixel format with order B,G,R,A.
+ * We presently ignore the attribute byte, so the code for reading
+ * these pixels is identical to the 24-bit routine above.
+ * This works because the actual pixel length is only known to read_pixel.
+ */
+
+#define get_32bit_row  get_24bit_row
+
+
+/*
+ * This method is for re-reading the input data in standard top-down
+ * row order.  The entire image has already been read into whole_image
+ * with proper conversion of pixel format, but it's in a funny row order.
+ */
+
+METHODDEF(JDIMENSION)
+get_memory_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
+{
+  tga_source_ptr source = (tga_source_ptr) sinfo;
+  JDIMENSION source_row;
+
+  /* Compute row of source that maps to current_row of normal order */
+  /* For now, assume image is bottom-up and not interlaced. */
+  /* NEEDS WORK to support interlaced images! */
+  source_row = cinfo->image_height - source->current_row - 1;
+
+  /* Fetch that row from virtual array */
+  source->pub.buffer = (*cinfo->mem->access_virt_sarray)
+    ((j_common_ptr) cinfo, source->whole_image,
+     source_row, (JDIMENSION) 1, FALSE);
+
+  source->current_row++;
+  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_memory_row on subsequent calls.
+ */
+
+METHODDEF(JDIMENSION)
+preload_image (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
+{
+  tga_source_ptr source = (tga_source_ptr) sinfo;
+  JDIMENSION row;
+  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);
+    }
+    source->pub.buffer = (*cinfo->mem->access_virt_sarray)
+      ((j_common_ptr) cinfo, source->whole_image, row, (JDIMENSION) 1, TRUE);
+    (*source->get_pixel_rows) (cinfo, sinfo);
+  }
+  if (progress != NULL)
+    progress->completed_extra_passes++;
+
+  /* Set up to read from the virtual array in unscrambled order */
+  source->pub.get_pixel_rows = get_memory_row;
+  source->current_row = 0;
+  /* And read the first row */
+  return get_memory_row(cinfo, sinfo);
+}
+
+
+/*
+ * Read the file header; return image size and component count.
+ */
+
+METHODDEF(void)
+start_input_tga (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
+{
+  tga_source_ptr source = (tga_source_ptr) sinfo;
+  U_CHAR targaheader[18];
+  int idlen, cmaptype, subtype, flags, interlace_type, components;
+  unsigned int width, height, maplen;
+  boolean is_bottom_up;
+
+#define GET_2B(offset)	((unsigned int) UCH(targaheader[offset]) + \
+			 (((unsigned int) UCH(targaheader[offset+1])) << 8))
+
+  if (! ReadOK(source->pub.input_file, targaheader, 18))
+    ERREXIT(cinfo, JERR_INPUT_EOF);
+
+  /* Pretend "15-bit" pixels are 16-bit --- we ignore attribute bit anyway */
+  if (targaheader[16] == 15)
+    targaheader[16] = 16;
+
+  idlen = UCH(targaheader[0]);
+  cmaptype = UCH(targaheader[1]);
+  subtype = UCH(targaheader[2]);
+  maplen = GET_2B(5);
+  width = GET_2B(12);
+  height = GET_2B(14);
+  source->pixel_size = UCH(targaheader[16]) >> 3;
+  flags = UCH(targaheader[17]);	/* Image Descriptor byte */
+
+  is_bottom_up = ((flags & 0x20) == 0);	/* bit 5 set => top-down */
+  interlace_type = flags >> 6;	/* bits 6/7 are interlace code */
+
+  if (cmaptype > 1 ||		/* cmaptype must be 0 or 1 */
+      source->pixel_size < 1 || source->pixel_size > 4 ||
+      (UCH(targaheader[16]) & 7) != 0 || /* bits/pixel must be multiple of 8 */
+      interlace_type != 0)	/* currently don't allow interlaced image */
+    ERREXIT(cinfo, JERR_TGA_BADPARMS);
+  
+  if (subtype > 8) {
+    /* It's an RLE-coded file */
+    source->read_pixel = read_rle_pixel;
+    source->block_count = source->dup_pixel_count = 0;
+    subtype -= 8;
+  } else {
+    /* Non-RLE file */
+    source->read_pixel = read_non_rle_pixel;
+  }
+
+  /* Now should have subtype 1, 2, or 3 */
+  components = 3;		/* until proven different */
+  cinfo->in_color_space = JCS_RGB;
+
+  switch (subtype) {
+  case 1:			/* Colormapped image */
+    if (source->pixel_size == 1 && cmaptype == 1)
+      source->get_pixel_rows = get_8bit_row;
+    else
+      ERREXIT(cinfo, JERR_TGA_BADPARMS);
+    TRACEMS2(cinfo, 1, JTRC_TGA_MAPPED, width, height);
+    break;
+  case 2:			/* RGB image */
+    switch (source->pixel_size) {
+    case 2:
+      source->get_pixel_rows = get_16bit_row;
+      break;
+    case 3:
+      source->get_pixel_rows = get_24bit_row;
+      break;
+    case 4:
+      source->get_pixel_rows = get_32bit_row;
+      break;
+    default:
+      ERREXIT(cinfo, JERR_TGA_BADPARMS);
+      break;
+    }
+    TRACEMS2(cinfo, 1, JTRC_TGA, width, height);
+    break;
+  case 3:			/* Grayscale image */
+    components = 1;
+    cinfo->in_color_space = JCS_GRAYSCALE;
+    if (source->pixel_size == 1)
+      source->get_pixel_rows = get_8bit_gray_row;
+    else
+      ERREXIT(cinfo, JERR_TGA_BADPARMS);
+    TRACEMS2(cinfo, 1, JTRC_TGA_GRAY, width, height);
+    break;
+  default:
+    ERREXIT(cinfo, JERR_TGA_BADPARMS);
+    break;
+  }
+
+  if (is_bottom_up) {
+    /* Create a virtual array to buffer the upside-down image. */
+    source->whole_image = (*cinfo->mem->request_virt_sarray)
+      ((j_common_ptr) cinfo, JPOOL_IMAGE, FALSE,
+       (JDIMENSION) width * components, (JDIMENSION) height, (JDIMENSION) 1);
+    if (cinfo->progress != NULL) {
+      cd_progress_ptr progress = (cd_progress_ptr) cinfo->progress;
+      progress->total_extra_passes++; /* count file input as separate pass */
+    }
+    /* source->pub.buffer will point to the virtual array. */
+    source->pub.buffer_height = 1; /* in case anyone looks at it */
+    source->pub.get_pixel_rows = preload_image;
+  } else {
+    /* Don't need a virtual array, but do need a one-row input buffer. */
+    source->whole_image = NULL;
+    source->pub.buffer = (*cinfo->mem->alloc_sarray)
+      ((j_common_ptr) cinfo, JPOOL_IMAGE,
+       (JDIMENSION) width * components, (JDIMENSION) 1);
+    source->pub.buffer_height = 1;
+    source->pub.get_pixel_rows = source->get_pixel_rows;
+  }
+  
+  while (idlen--)		/* Throw away ID field */
+    (void) read_byte(source);
+
+  if (maplen > 0) {
+    if (maplen > 256 || GET_2B(3) != 0)
+      ERREXIT(cinfo, JERR_TGA_BADCMAP);
+    /* Allocate space to store the colormap */
+    source->colormap = (*cinfo->mem->alloc_sarray)
+      ((j_common_ptr) cinfo, JPOOL_IMAGE, (JDIMENSION) maplen, (JDIMENSION) 3);
+    /* and read it from the file */
+    read_colormap(source, (int) maplen, UCH(targaheader[7]));
+  } else {
+    if (cmaptype)		/* but you promised a cmap! */
+      ERREXIT(cinfo, JERR_TGA_BADPARMS);
+    source->colormap = NULL;
+  }
+
+  cinfo->input_components = components;
+  cinfo->data_precision = 8;
+  cinfo->image_width = width;
+  cinfo->image_height = height;
+}
+
+
+/*
+ * Finish up at the end of the file.
+ */
+
+METHODDEF(void)
+finish_input_tga (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
+{
+  /* no work */
+}
+
+
+/*
+ * The module selection routine for Targa format input.
+ */
+
+GLOBAL(cjpeg_source_ptr)
+jinit_read_targa (j_compress_ptr cinfo)
+{
+  tga_source_ptr source;
+
+  /* Create module interface object */
+  source = (tga_source_ptr)
+      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
+				  SIZEOF(tga_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_tga;
+  source->pub.finish_input = finish_input_tga;
+
+  return (cjpeg_source_ptr) source;
+}
+
+#endif /* TARGA_SUPPORTED */