Mercurial > hgrepos > Python2 > PyMuPDF

comparison mupdf-source/thirdparty/libjpeg/wrtarga.c @ 2:b50eed0cc0ef upstream

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. The directory name has changed: no version number in the expanded directory now.
author Franz Glasner <fzglas.hg@dom66.de>
date Mon, 15 Sep 2025 11:43:07 +0200
parents
children
comparison
equal deleted inserted replaced
1:1d09e1dec1d9 2:b50eed0cc0ef
1 /*
2 * wrtarga.c
3 *
4 * Copyright (C) 1991-1996, Thomas G. Lane.
5 * Modified 2015-2019 by Guido Vollbeding.
6 * This file is part of the Independent JPEG Group's software.
7 * For conditions of distribution and use, see the accompanying README file.
8 *
9 * This file contains routines to write output images in Targa format.
10 *
11 * These routines may need modification for non-Unix environments or
12 * specialized applications. As they stand, they assume output to
13 * an ordinary stdio stream.
14 *
15 * Based on code contributed by Lee Daniel Crocker.
16 */
17
18 #include "cdjpeg.h" /* Common decls for cjpeg/djpeg applications */
19
20 #ifdef TARGA_SUPPORTED
21
22
23 /*
24 * To support 12-bit JPEG data, we'd have to scale output down to 8 bits.
25 * This is not yet implemented.
26 */
27
28 #if BITS_IN_JSAMPLE != 8
29 Sorry, this code only copes with 8-bit JSAMPLEs. /* deliberate syntax err */
30 #endif
31
32 /*
33 * The output buffer needs to be writable by fwrite(). On PCs, we must
34 * allocate the buffer in near data space, because we are assuming small-data
35 * memory model, wherein fwrite() can't reach far memory. If you need to
36 * process very wide images on a PC, you might have to compile in large-memory
37 * model, or else replace fwrite() with a putc() loop --- which will be much
38 * slower.
39 */
40
41
42 /* Private version of data destination object */
43
44 typedef struct {
45 struct djpeg_dest_struct pub; /* public fields */
46
47 char *iobuffer; /* physical I/O buffer */
48 JDIMENSION buffer_width; /* width of one row */
49 } tga_dest_struct;
50
51 typedef tga_dest_struct * tga_dest_ptr;
52
53
54 LOCAL(void)
55 write_header (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo, int num_colors)
56 /* Create and write a Targa header */
57 {
58 char targaheader[18];
59
60 /* Set unused fields of header to 0 */
61 MEMZERO(targaheader, SIZEOF(targaheader));
62
63 if (num_colors > 0) {
64 targaheader[1] = 1; /* color map type 1 */
65 targaheader[5] = (char) (num_colors & 0xFF);
66 targaheader[6] = (char) (num_colors >> 8);
67 targaheader[7] = 24; /* 24 bits per cmap entry */
68 }
69
70 targaheader[12] = (char) (cinfo->output_width & 0xFF);
71 targaheader[13] = (char) (cinfo->output_width >> 8);
72 targaheader[14] = (char) (cinfo->output_height & 0xFF);
73 targaheader[15] = (char) (cinfo->output_height >> 8);
74 targaheader[17] = 0x20; /* Top-down, non-interlaced */
75
76 if (cinfo->out_color_space == JCS_GRAYSCALE) {
77 targaheader[2] = 3; /* image type = uncompressed grayscale */
78 targaheader[16] = 8; /* bits per pixel */
79 } else { /* must be RGB */
80 if (num_colors > 0) {
81 targaheader[2] = 1; /* image type = colormapped RGB */
82 targaheader[16] = 8;
83 } else {
84 targaheader[2] = 2; /* image type = uncompressed RGB */
85 targaheader[16] = 24;
86 }
87 }
88
89 if (JFWRITE(dinfo->output_file, targaheader, 18) != (size_t) 18)
90 ERREXIT(cinfo, JERR_FILE_WRITE);
91 }
92
93
94 /*
95 * Write some pixel data.
96 * In this module rows_supplied will always be 1.
97 */
98
99 METHODDEF(void)
100 put_pixel_rows (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
101 JDIMENSION rows_supplied)
102 /* used for unquantized full-color output */
103 {
104 tga_dest_ptr dest = (tga_dest_ptr) dinfo;
105 register JSAMPROW inptr;
106 register char * outptr;
107 register JDIMENSION col;
108
109 inptr = dest->pub.buffer[0];
110 outptr = dest->iobuffer;
111 for (col = cinfo->output_width; col > 0; col--) {
112 outptr[0] = (char) GETJSAMPLE(inptr[2]); /* RGB to BGR order */
113 outptr[1] = (char) GETJSAMPLE(inptr[1]);
114 outptr[2] = (char) GETJSAMPLE(inptr[0]);
115 inptr += 3, outptr += 3;
116 }
117 (void) JFWRITE(dest->pub.output_file, dest->iobuffer, dest->buffer_width);
118 }
119
120 METHODDEF(void)
121 put_gray_rows (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
122 JDIMENSION rows_supplied)
123 /* used for grayscale OR quantized color output */
124 {
125 tga_dest_ptr dest = (tga_dest_ptr) dinfo;
126 register JSAMPROW inptr;
127 register char * outptr;
128 register JDIMENSION col;
129
130 inptr = dest->pub.buffer[0];
131 outptr = dest->iobuffer;
132 for (col = cinfo->output_width; col > 0; col--) {
133 *outptr++ = (char) GETJSAMPLE(*inptr++);
134 }
135 (void) JFWRITE(dest->pub.output_file, dest->iobuffer, dest->buffer_width);
136 }
137
138
139 /*
140 * Write some demapped pixel data when color quantization is in effect.
141 * For Targa, this is only applied to grayscale data.
142 */
143
144 METHODDEF(void)
145 put_demapped_gray (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
146 JDIMENSION rows_supplied)
147 {
148 tga_dest_ptr dest = (tga_dest_ptr) dinfo;
149 register JSAMPROW inptr;
150 register char * outptr;
151 register JSAMPROW color_map0 = cinfo->colormap[0];
152 register JDIMENSION col;
153
154 inptr = dest->pub.buffer[0];
155 outptr = dest->iobuffer;
156 for (col = cinfo->output_width; col > 0; col--) {
157 *outptr++ = (char) GETJSAMPLE(color_map0[GETJSAMPLE(*inptr++)]);
158 }
159 (void) JFWRITE(dest->pub.output_file, dest->iobuffer, dest->buffer_width);
160 }
161
162
163 /*
164 * Startup: write the file header.
165 */
166
167 METHODDEF(void)
168 start_output_tga (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
169 {
170 int num_colors, i;
171 FILE *outfile;
172
173 switch (cinfo->out_color_space) {
174 case JCS_GRAYSCALE:
175 /* Targa doesn't have a mapped grayscale format, so we will */
176 /* demap quantized gray output. Never emit a colormap. */
177 write_header(cinfo, dinfo, 0);
178 if (cinfo->quantize_colors)
179 dinfo->put_pixel_rows = put_demapped_gray;
180 else
181 dinfo->put_pixel_rows = put_gray_rows;
182 break;
183 case JCS_RGB:
184 if (cinfo->quantize_colors) {
185 /* We only support 8-bit colormap indexes, so only 256 colors */
186 num_colors = cinfo->actual_number_of_colors;
187 if (num_colors > 256)
188 ERREXIT1(cinfo, JERR_TOO_MANY_COLORS, num_colors);
189 write_header(cinfo, dinfo, num_colors);
190 /* Write the colormap. Note Targa uses BGR byte order */
191 outfile = dinfo->output_file;
192 for (i = 0; i < num_colors; i++) {
193 putc(GETJSAMPLE(cinfo->colormap[2][i]), outfile);
194 putc(GETJSAMPLE(cinfo->colormap[1][i]), outfile);
195 putc(GETJSAMPLE(cinfo->colormap[0][i]), outfile);
196 }
197 dinfo->put_pixel_rows = put_gray_rows;
198 } else {
199 write_header(cinfo, dinfo, 0);
200 dinfo->put_pixel_rows = put_pixel_rows;
201 }
202 break;
203 default:
204 ERREXIT(cinfo, JERR_TGA_COLORSPACE);
205 }
206 }
207
208
209 /*
210 * Finish up at the end of the file.
211 */
212
213 METHODDEF(void)
214 finish_output_tga (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
215 {
216 /* Make sure we wrote the output file OK */
217 JFFLUSH(dinfo->output_file);
218 if (JFERROR(dinfo->output_file))
219 ERREXIT(cinfo, JERR_FILE_WRITE);
220 }
221
222
223 /*
224 * The module selection routine for Targa format output.
225 */
226
227 GLOBAL(djpeg_dest_ptr)
228 jinit_write_targa (j_decompress_ptr cinfo)
229 {
230 tga_dest_ptr dest;
231
232 /* Create module interface object, fill in method pointers */
233 dest = (tga_dest_ptr) (*cinfo->mem->alloc_small)
234 ((j_common_ptr) cinfo, JPOOL_IMAGE, SIZEOF(tga_dest_struct));
235 dest->pub.start_output = start_output_tga;
236 dest->pub.finish_output = finish_output_tga;
237
238 /* Calculate output image dimensions so we can allocate space */
239 jpeg_calc_output_dimensions(cinfo);
240
241 /* Create I/O buffer. Note we make this near on a PC. */
242 dest->buffer_width = cinfo->output_width * cinfo->output_components;
243 dest->iobuffer = (char *) (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo,
244 JPOOL_IMAGE, (size_t) dest->buffer_width * SIZEOF(char));
245
246 /* Create decompressor output buffer. */
247 dest->pub.buffer = (*cinfo->mem->alloc_sarray) ((j_common_ptr) cinfo,
248 JPOOL_IMAGE, dest->buffer_width, (JDIMENSION) 1);
249 dest->pub.buffer_height = 1;
250
251 return &dest->pub;
252 }
253
254 #endif /* TARGA_SUPPORTED */