Diff: includes/wrtarga.c

Revision:

0:791a779d6220

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/includes/wrtarga.c	Mon Jul 31 09:16:35 2017 +0000
@@ -0,0 +1,254 @@
+/*
+ * wrtarga.c
+ *
+ * Copyright (C) 1991-1996, Thomas G. Lane.
+ * Modified 2015 by Guido Vollbeding.
+ * 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 write output images in Targa format.
+ *
+ * These routines may need modification for non-Unix environments or
+ * specialized applications.  As they stand, they assume output to
+ * an ordinary stdio stream.
+ *
+ * Based on code contributed by Lee Daniel Crocker.
+ */
+
+#include "cdjpeg.h"		/* Common decls for cjpeg/djpeg applications */
+
+#ifdef TARGA_SUPPORTED
+
+
+/*
+ * To support 12-bit JPEG data, we'd have to scale output down to 8 bits.
+ * This is not yet implemented.
+ */
+
+#if BITS_IN_JSAMPLE != 8
+  Sorry, this code only copes with 8-bit JSAMPLEs. /* deliberate syntax err */
+#endif
+
+/*
+ * The output buffer needs to be writable by fwrite().  On PCs, we must
+ * allocate the buffer in near data space, because we are assuming small-data
+ * memory model, wherein fwrite() can't reach far memory.  If you need to
+ * process very wide images on a PC, you might have to compile in large-memory
+ * model, or else replace fwrite() with a putc() loop --- which will be much
+ * slower.
+ */
+
+
+/* Private version of data destination object */
+
+typedef struct {
+  struct djpeg_dest_struct pub;	/* public fields */
+
+  char *iobuffer;		/* physical I/O buffer */
+  JDIMENSION buffer_width;	/* width of one row */
+} tga_dest_struct;
+
+typedef tga_dest_struct * tga_dest_ptr;
+
+
+LOCAL(void)
+write_header (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo, int num_colors)
+/* Create and write a Targa header */
+{
+  char targaheader[18];
+
+  /* Set unused fields of header to 0 */
+  MEMZERO(targaheader, SIZEOF(targaheader));
+
+  if (num_colors > 0) {
+    targaheader[1] = 1;		/* color map type 1 */
+    targaheader[5] = (char) (num_colors & 0xFF);
+    targaheader[6] = (char) (num_colors >> 8);
+    targaheader[7] = 24;	/* 24 bits per cmap entry */
+  }
+
+  targaheader[12] = (char) (cinfo->output_width & 0xFF);
+  targaheader[13] = (char) (cinfo->output_width >> 8);
+  targaheader[14] = (char) (cinfo->output_height & 0xFF);
+  targaheader[15] = (char) (cinfo->output_height >> 8);
+  targaheader[17] = 0x20;	/* Top-down, non-interlaced */
+
+  if (cinfo->out_color_space == JCS_GRAYSCALE) {
+    targaheader[2] = 3;		/* image type = uncompressed grayscale */
+    targaheader[16] = 8;	/* bits per pixel */
+  } else {			/* must be RGB */
+    if (num_colors > 0) {
+      targaheader[2] = 1;	/* image type = colormapped RGB */
+      targaheader[16] = 8;
+    } else {
+      targaheader[2] = 2;	/* image type = uncompressed RGB */
+      targaheader[16] = 24;
+    }
+  }
+
+  if (JFWRITE(dinfo->output_file, targaheader, 18) != (size_t) 18)
+    ERREXIT(cinfo, JERR_FILE_WRITE);
+}
+
+
+/*
+ * Write some pixel data.
+ * In this module rows_supplied will always be 1.
+ */
+
+METHODDEF(void)
+put_pixel_rows (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
+		JDIMENSION rows_supplied)
+/* used for unquantized full-color output */
+{
+  tga_dest_ptr dest = (tga_dest_ptr) dinfo;
+  register JSAMPROW inptr;
+  register char * outptr;
+  register JDIMENSION col;
+
+  inptr = dest->pub.buffer[0];
+  outptr = dest->iobuffer;
+  for (col = cinfo->output_width; col > 0; col--) {
+    outptr[0] = (char) GETJSAMPLE(inptr[2]); /* RGB to BGR order */
+    outptr[1] = (char) GETJSAMPLE(inptr[1]);
+    outptr[2] = (char) GETJSAMPLE(inptr[0]);
+    inptr += 3, outptr += 3;
+  }
+  (void) JFWRITE(dest->pub.output_file, dest->iobuffer, dest->buffer_width);
+}
+
+METHODDEF(void)
+put_gray_rows (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
+	       JDIMENSION rows_supplied)
+/* used for grayscale OR quantized color output */
+{
+  tga_dest_ptr dest = (tga_dest_ptr) dinfo;
+  register JSAMPROW inptr;
+  register char * outptr;
+  register JDIMENSION col;
+
+  inptr = dest->pub.buffer[0];
+  outptr = dest->iobuffer;
+  for (col = cinfo->output_width; col > 0; col--) {
+    *outptr++ = (char) GETJSAMPLE(*inptr++);
+  }
+  (void) JFWRITE(dest->pub.output_file, dest->iobuffer, dest->buffer_width);
+}
+
+
+/*
+ * Write some demapped pixel data when color quantization is in effect.
+ * For Targa, this is only applied to grayscale data.
+ */
+
+METHODDEF(void)
+put_demapped_gray (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
+		   JDIMENSION rows_supplied)
+{
+  tga_dest_ptr dest = (tga_dest_ptr) dinfo;
+  register JSAMPROW inptr;
+  register char * outptr;
+  register JSAMPROW color_map0 = cinfo->colormap[0];
+  register JDIMENSION col;
+
+  inptr = dest->pub.buffer[0];
+  outptr = dest->iobuffer;
+  for (col = cinfo->output_width; col > 0; col--) {
+    *outptr++ = (char) GETJSAMPLE(color_map0[GETJSAMPLE(*inptr++)]);
+  }
+  (void) JFWRITE(dest->pub.output_file, dest->iobuffer, dest->buffer_width);
+}
+
+
+/*
+ * Startup: write the file header.
+ */
+
+METHODDEF(void)
+start_output_tga (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
+{
+  tga_dest_ptr dest = (tga_dest_ptr) dinfo;
+  int num_colors, i;
+  FILE *outfile;
+
+  if (cinfo->out_color_space == JCS_GRAYSCALE) {
+    /* Targa doesn't have a mapped grayscale format, so we will */
+    /* demap quantized gray output.  Never emit a colormap. */
+    write_header(cinfo, dinfo, 0);
+    if (cinfo->quantize_colors)
+      dest->pub.put_pixel_rows = put_demapped_gray;
+    else
+      dest->pub.put_pixel_rows = put_gray_rows;
+  } else if (cinfo->out_color_space == JCS_RGB) {
+    if (cinfo->quantize_colors) {
+      /* We only support 8-bit colormap indexes, so only 256 colors */
+      num_colors = cinfo->actual_number_of_colors;
+      if (num_colors > 256)
+	ERREXIT1(cinfo, JERR_TOO_MANY_COLORS, num_colors);
+      write_header(cinfo, dinfo, num_colors);
+      /* Write the colormap.  Note Targa uses BGR byte order */
+      outfile = dest->pub.output_file;
+      for (i = 0; i < num_colors; i++) {
+	putc(GETJSAMPLE(cinfo->colormap[2][i]), outfile);
+	putc(GETJSAMPLE(cinfo->colormap[1][i]), outfile);
+	putc(GETJSAMPLE(cinfo->colormap[0][i]), outfile);
+      }
+      dest->pub.put_pixel_rows = put_gray_rows;
+    } else {
+      write_header(cinfo, dinfo, 0);
+      dest->pub.put_pixel_rows = put_pixel_rows;
+    }
+  } else {
+    ERREXIT(cinfo, JERR_TGA_COLORSPACE);
+  }
+}
+
+
+/*
+ * Finish up at the end of the file.
+ */
+
+METHODDEF(void)
+finish_output_tga (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
+{
+  /* Make sure we wrote the output file OK */
+  fflush(dinfo->output_file);
+  if (ferror(dinfo->output_file))
+    ERREXIT(cinfo, JERR_FILE_WRITE);
+}
+
+
+/*
+ * The module selection routine for Targa format output.
+ */
+
+GLOBAL(djpeg_dest_ptr)
+jinit_write_targa (j_decompress_ptr cinfo)
+{
+  tga_dest_ptr dest;
+
+  /* Create module interface object, fill in method pointers */
+  dest = (tga_dest_ptr)
+      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
+				  SIZEOF(tga_dest_struct));
+  dest->pub.start_output = start_output_tga;
+  dest->pub.finish_output = finish_output_tga;
+
+  /* Calculate output image dimensions so we can allocate space */
+  jpeg_calc_output_dimensions(cinfo);
+
+  /* Create I/O buffer.  Note we make this near on a PC. */
+  dest->buffer_width = cinfo->output_width * cinfo->output_components;
+  dest->iobuffer = (char *)
+    (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
+				(size_t) (dest->buffer_width * SIZEOF(char)));
+
+  /* Create decompressor output buffer. */
+  dest->pub.buffer = (*cinfo->mem->alloc_sarray)
+    ((j_common_ptr) cinfo, JPOOL_IMAGE, dest->buffer_width, (JDIMENSION) 1);
+  dest->pub.buffer_height = 1;
+
+  return &dest->pub;
+}
+
+#endif /* TARGA_SUPPORTED */