45e751b389d9422d61020f2a2367ad6789f0274c
[libav.git] / libavcodec / pcx.c
1 /*
2 * PC Paintbrush PCX (.pcx) image decoder
3 * Copyright (c) 2007, 2008 Ivo van Poorten
4 *
5 * This decoder does not support CGA palettes. I am unable to find samples
6 * and Netpbm cannot generate them.
7 *
8 * This file is part of Libav.
9 *
10 * Libav is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU Lesser General Public
12 * License as published by the Free Software Foundation; either
13 * version 2.1 of the License, or (at your option) any later version.
14 *
15 * Libav is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * Lesser General Public License for more details.
19 *
20 * You should have received a copy of the GNU Lesser General Public
21 * License along with Libav; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 */
24
25 #include "libavutil/imgutils.h"
26 #include "avcodec.h"
27 #include "bytestream.h"
28 #include "get_bits.h"
29
30 typedef struct PCXContext {
31 AVFrame picture;
32 } PCXContext;
33
34 static av_cold int pcx_init(AVCodecContext *avctx) {
35 PCXContext *s = avctx->priv_data;
36
37 avcodec_get_frame_defaults(&s->picture);
38 avctx->coded_frame= &s->picture;
39
40 return 0;
41 }
42
43 /**
44 * @return advanced src pointer
45 */
46 static const uint8_t *pcx_rle_decode(const uint8_t *src, uint8_t *dst,
47 unsigned int bytes_per_scanline, int compressed) {
48 unsigned int i = 0;
49 unsigned char run, value;
50
51 if (compressed) {
52 while (i<bytes_per_scanline) {
53 run = 1;
54 value = *src++;
55 if (value >= 0xc0) {
56 run = value & 0x3f;
57 value = *src++;
58 }
59 while (i<bytes_per_scanline && run--)
60 dst[i++] = value;
61 }
62 } else {
63 memcpy(dst, src, bytes_per_scanline);
64 src += bytes_per_scanline;
65 }
66
67 return src;
68 }
69
70 static void pcx_palette(const uint8_t **src, uint32_t *dst, unsigned int pallen) {
71 unsigned int i;
72
73 for (i=0; i<pallen; i++)
74 *dst++ = bytestream_get_be24(src);
75 if (pallen < 256)
76 memset(dst, 0, (256 - pallen) * sizeof(*dst));
77 }
78
79 static int pcx_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
80 AVPacket *avpkt) {
81 const uint8_t *buf = avpkt->data;
82 int buf_size = avpkt->size;
83 PCXContext * const s = avctx->priv_data;
84 AVFrame *picture = data;
85 AVFrame * const p = &s->picture;
86 int compressed, xmin, ymin, xmax, ymax;
87 unsigned int w, h, bits_per_pixel, bytes_per_line, nplanes, stride, y, x,
88 bytes_per_scanline;
89 uint8_t *ptr;
90 uint8_t const *bufstart = buf;
91 uint8_t *scanline;
92 int ret = -1;
93
94 if (buf[0] != 0x0a || buf[1] > 5) {
95 av_log(avctx, AV_LOG_ERROR, "this is not PCX encoded data\n");
96 return -1;
97 }
98
99 compressed = buf[2];
100 xmin = AV_RL16(buf+ 4);
101 ymin = AV_RL16(buf+ 6);
102 xmax = AV_RL16(buf+ 8);
103 ymax = AV_RL16(buf+10);
104
105 if (xmax < xmin || ymax < ymin) {
106 av_log(avctx, AV_LOG_ERROR, "invalid image dimensions\n");
107 return -1;
108 }
109
110 w = xmax - xmin + 1;
111 h = ymax - ymin + 1;
112
113 bits_per_pixel = buf[3];
114 bytes_per_line = AV_RL16(buf+66);
115 nplanes = buf[65];
116 bytes_per_scanline = nplanes * bytes_per_line;
117
118 if (bytes_per_scanline < w * bits_per_pixel * nplanes / 8) {
119 av_log(avctx, AV_LOG_ERROR, "PCX data is corrupted\n");
120 return -1;
121 }
122
123 switch ((nplanes<<8) + bits_per_pixel) {
124 case 0x0308:
125 avctx->pix_fmt = AV_PIX_FMT_RGB24;
126 break;
127 case 0x0108:
128 case 0x0104:
129 case 0x0102:
130 case 0x0101:
131 case 0x0401:
132 case 0x0301:
133 case 0x0201:
134 avctx->pix_fmt = AV_PIX_FMT_PAL8;
135 break;
136 default:
137 av_log(avctx, AV_LOG_ERROR, "invalid PCX file\n");
138 return -1;
139 }
140
141 buf += 128;
142
143 if (p->data[0])
144 avctx->release_buffer(avctx, p);
145
146 if (av_image_check_size(w, h, 0, avctx))
147 return -1;
148 if (w != avctx->width || h != avctx->height)
149 avcodec_set_dimensions(avctx, w, h);
150 if (avctx->get_buffer(avctx, p) < 0) {
151 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
152 return -1;
153 }
154
155 p->pict_type = AV_PICTURE_TYPE_I;
156
157 ptr = p->data[0];
158 stride = p->linesize[0];
159
160 scanline = av_malloc(bytes_per_scanline);
161 if (!scanline)
162 return AVERROR(ENOMEM);
163
164 if (nplanes == 3 && bits_per_pixel == 8) {
165 for (y=0; y<h; y++) {
166 buf = pcx_rle_decode(buf, scanline, bytes_per_scanline, compressed);
167
168 for (x=0; x<w; x++) {
169 ptr[3*x ] = scanline[x ];
170 ptr[3*x+1] = scanline[x+ bytes_per_line ];
171 ptr[3*x+2] = scanline[x+(bytes_per_line<<1)];
172 }
173
174 ptr += stride;
175 }
176
177 } else if (nplanes == 1 && bits_per_pixel == 8) {
178 const uint8_t *palstart = bufstart + buf_size - 769;
179
180 for (y=0; y<h; y++, ptr+=stride) {
181 buf = pcx_rle_decode(buf, scanline, bytes_per_scanline, compressed);
182 memcpy(ptr, scanline, w);
183 }
184
185 if (buf != palstart) {
186 av_log(avctx, AV_LOG_WARNING, "image data possibly corrupted\n");
187 buf = palstart;
188 }
189 if (*buf++ != 12) {
190 av_log(avctx, AV_LOG_ERROR, "expected palette after image data\n");
191 goto end;
192 }
193
194 } else if (nplanes == 1) { /* all packed formats, max. 16 colors */
195 GetBitContext s;
196
197 for (y=0; y<h; y++) {
198 init_get_bits(&s, scanline, bytes_per_scanline<<3);
199
200 buf = pcx_rle_decode(buf, scanline, bytes_per_scanline, compressed);
201
202 for (x=0; x<w; x++)
203 ptr[x] = get_bits(&s, bits_per_pixel);
204 ptr += stride;
205 }
206
207 } else { /* planar, 4, 8 or 16 colors */
208 int i;
209
210 for (y=0; y<h; y++) {
211 buf = pcx_rle_decode(buf, scanline, bytes_per_scanline, compressed);
212
213 for (x=0; x<w; x++) {
214 int m = 0x80 >> (x&7), v = 0;
215 for (i=nplanes - 1; i>=0; i--) {
216 v <<= 1;
217 v += !!(scanline[i*bytes_per_line + (x>>3)] & m);
218 }
219 ptr[x] = v;
220 }
221 ptr += stride;
222 }
223 }
224
225 if (nplanes == 1 && bits_per_pixel == 8) {
226 pcx_palette(&buf, (uint32_t *) p->data[1], 256);
227 } else if (bits_per_pixel < 8) {
228 const uint8_t *palette = bufstart+16;
229 pcx_palette(&palette, (uint32_t *) p->data[1], 16);
230 }
231
232 *picture = s->picture;
233 *data_size = sizeof(AVFrame);
234
235 ret = buf - bufstart;
236 end:
237 av_free(scanline);
238 return ret;
239 }
240
241 static av_cold int pcx_end(AVCodecContext *avctx) {
242 PCXContext *s = avctx->priv_data;
243
244 if(s->picture.data[0])
245 avctx->release_buffer(avctx, &s->picture);
246
247 return 0;
248 }
249
250 AVCodec ff_pcx_decoder = {
251 .name = "pcx",
252 .type = AVMEDIA_TYPE_VIDEO,
253 .id = AV_CODEC_ID_PCX,
254 .priv_data_size = sizeof(PCXContext),
255 .init = pcx_init,
256 .close = pcx_end,
257 .decode = pcx_decode_frame,
258 .capabilities = CODEC_CAP_DR1,
259 .long_name = NULL_IF_CONFIG_SMALL("PC Paintbrush PCX image"),
260 };