File: wrtarga.c

package info (click to toggle)
libjpeg-mmx 0.1.3-3
  • links: PTS
  • area: main
  • in suites: woody
  • size: 2,700 kB
  • ctags: 2,672
  • sloc: ansic: 24,900; sh: 4,565; makefile: 59
file content (253 lines) | stat: -rw-r--r-- 7,524 bytes parent folder | download | duplicates (88)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
/*
 * wrtarga.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 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 gray-scale */
    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 (djpeg_dest_ptr) dest;
}

#endif /* TARGA_SUPPORTED */