a5c13960bde5901048acd9652a47b877921d64ff
[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 #include "internal.h"
30
31 typedef struct PCXContext {
32 AVFrame picture;
33 } PCXContext;
34
35 static av_cold int pcx_init(AVCodecContext *avctx) {
36 PCXContext *s = avctx->priv_data;
37
38 avcodec_get_frame_defaults(&s->picture);
39 avctx->coded_frame= &s->picture;
40
41 return 0;
42 }
43
44 /**
45 * @return advanced src pointer
46 */
47 static const uint8_t *pcx_rle_decode(const uint8_t *src, uint8_t *dst,
48 unsigned int bytes_per_scanline, int compressed) {
49 unsigned int i = 0;
50 unsigned char run, value;
51
52 if (compressed) {
53 while (i<bytes_per_scanline) {
54 run = 1;
55 value = *src++;
56 if (value >= 0xc0) {
57 run = value & 0x3f;
58 value = *src++;
59 }
60 while (i<bytes_per_scanline && run--)
61 dst[i++] = value;
62 }
63 } else {
64 memcpy(dst, src, bytes_per_scanline);
65 src += bytes_per_scanline;
66 }
67
68 return src;
69 }
70
71 static void pcx_palette(const uint8_t **src, uint32_t *dst, unsigned int pallen) {
72 unsigned int i;
73
74 for (i=0; i<pallen; i++)
75 *dst++ = bytestream_get_be24(src);
76 if (pallen < 256)
77 memset(dst, 0, (256 - pallen) * sizeof(*dst));
78 }
79
80 static int pcx_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
81 AVPacket *avpkt) {
82 const uint8_t *buf = avpkt->data;
83 int buf_size = avpkt->size;
84 PCXContext * const s = avctx->priv_data;
85 AVFrame *picture = data;
86 AVFrame * const p = &s->picture;
87 int compressed, xmin, ymin, xmax, ymax;
88 unsigned int w, h, bits_per_pixel, bytes_per_line, nplanes, stride, y, x,
89 bytes_per_scanline;
90 uint8_t *ptr;
91 uint8_t const *bufstart = buf;
92 uint8_t *scanline;
93 int ret = -1;
94
95 if (buf[0] != 0x0a || buf[1] > 5) {
96 av_log(avctx, AV_LOG_ERROR, "this is not PCX encoded data\n");
97 return -1;
98 }
99
100 compressed = buf[2];
101 xmin = AV_RL16(buf+ 4);
102 ymin = AV_RL16(buf+ 6);
103 xmax = AV_RL16(buf+ 8);
104 ymax = AV_RL16(buf+10);
105
106 if (xmax < xmin || ymax < ymin) {
107 av_log(avctx, AV_LOG_ERROR, "invalid image dimensions\n");
108 return -1;
109 }
110
111 w = xmax - xmin + 1;
112 h = ymax - ymin + 1;
113
114 bits_per_pixel = buf[3];
115 bytes_per_line = AV_RL16(buf+66);
116 nplanes = buf[65];
117 bytes_per_scanline = nplanes * bytes_per_line;
118
119 if (bytes_per_scanline < w * bits_per_pixel * nplanes / 8) {
120 av_log(avctx, AV_LOG_ERROR, "PCX data is corrupted\n");
121 return -1;
122 }
123
124 switch ((nplanes<<8) + bits_per_pixel) {
125 case 0x0308:
126 avctx->pix_fmt = AV_PIX_FMT_RGB24;
127 break;
128 case 0x0108:
129 case 0x0104:
130 case 0x0102:
131 case 0x0101:
132 case 0x0401:
133 case 0x0301:
134 case 0x0201:
135 avctx->pix_fmt = AV_PIX_FMT_PAL8;
136 break;
137 default:
138 av_log(avctx, AV_LOG_ERROR, "invalid PCX file\n");
139 return -1;
140 }
141
142 buf += 128;
143
144 if (p->data[0])
145 avctx->release_buffer(avctx, p);
146
147 if (av_image_check_size(w, h, 0, avctx))
148 return -1;
149 if (w != avctx->width || h != avctx->height)
150 avcodec_set_dimensions(avctx, w, h);
151 if (ff_get_buffer(avctx, p) < 0) {
152 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
153 return -1;
154 }
155
156 p->pict_type = AV_PICTURE_TYPE_I;
157
158 ptr = p->data[0];
159 stride = p->linesize[0];
160
161 scanline = av_malloc(bytes_per_scanline);
162 if (!scanline)
163 return AVERROR(ENOMEM);
164
165 if (nplanes == 3 && bits_per_pixel == 8) {
166 for (y=0; y<h; y++) {
167 buf = pcx_rle_decode(buf, scanline, bytes_per_scanline, compressed);
168
169 for (x=0; x<w; x++) {
170 ptr[3*x ] = scanline[x ];
171 ptr[3*x+1] = scanline[x+ bytes_per_line ];
172 ptr[3*x+2] = scanline[x+(bytes_per_line<<1)];
173 }
174
175 ptr += stride;
176 }
177
178 } else if (nplanes == 1 && bits_per_pixel == 8) {
179 const uint8_t *palstart = bufstart + buf_size - 769;
180
181 for (y=0; y<h; y++, ptr+=stride) {
182 buf = pcx_rle_decode(buf, scanline, bytes_per_scanline, compressed);
183 memcpy(ptr, scanline, w);
184 }
185
186 if (buf != palstart) {
187 av_log(avctx, AV_LOG_WARNING, "image data possibly corrupted\n");
188 buf = palstart;
189 }
190 if (*buf++ != 12) {
191 av_log(avctx, AV_LOG_ERROR, "expected palette after image data\n");
192 goto end;
193 }
194
195 } else if (nplanes == 1) { /* all packed formats, max. 16 colors */
196 GetBitContext s;
197
198 for (y=0; y<h; y++) {
199 init_get_bits(&s, scanline, bytes_per_scanline<<3);
200
201 buf = pcx_rle_decode(buf, scanline, bytes_per_scanline, compressed);
202
203 for (x=0; x<w; x++)
204 ptr[x] = get_bits(&s, bits_per_pixel);
205 ptr += stride;
206 }
207
208 } else { /* planar, 4, 8 or 16 colors */
209 int i;
210
211 for (y=0; y<h; y++) {
212 buf = pcx_rle_decode(buf, scanline, bytes_per_scanline, compressed);
213
214 for (x=0; x<w; x++) {
215 int m = 0x80 >> (x&7), v = 0;
216 for (i=nplanes - 1; i>=0; i--) {
217 v <<= 1;
218 v += !!(scanline[i*bytes_per_line + (x>>3)] & m);
219 }
220 ptr[x] = v;
221 }
222 ptr += stride;
223 }
224 }
225
226 if (nplanes == 1 && bits_per_pixel == 8) {
227 pcx_palette(&buf, (uint32_t *) p->data[1], 256);
228 } else if (bits_per_pixel < 8) {
229 const uint8_t *palette = bufstart+16;
230 pcx_palette(&palette, (uint32_t *) p->data[1], 16);
231 }
232
233 *picture = s->picture;
234 *data_size = sizeof(AVFrame);
235
236 ret = buf - bufstart;
237 end:
238 av_free(scanline);
239 return ret;
240 }
241
242 static av_cold int pcx_end(AVCodecContext *avctx) {
243 PCXContext *s = avctx->priv_data;
244
245 if(s->picture.data[0])
246 avctx->release_buffer(avctx, &s->picture);
247
248 return 0;
249 }
250
251 AVCodec ff_pcx_decoder = {
252 .name = "pcx",
253 .type = AVMEDIA_TYPE_VIDEO,
254 .id = AV_CODEC_ID_PCX,
255 .priv_data_size = sizeof(PCXContext),
256 .init = pcx_init,
257 .close = pcx_end,
258 .decode = pcx_decode_frame,
259 .capabilities = CODEC_CAP_DR1,
260 .long_name = NULL_IF_CONFIG_SMALL("PC Paintbrush PCX image"),
261 };