Pictor/PC Paint decoder
[libav.git] / libavcodec / pictordec.c
1 /*
2 * Pictor/PC Paint decoder
3 * Copyright (c) 2010 Peter Ross <pross@xvid.org>
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 /**
23 * @file libavcodec/picdec.c
24 * Pictor/PC Paint decoder
25 */
26
27 #include "avcodec.h"
28 #include "bytestream.h"
29 #include "cga_data.h"
30
31 typedef struct PicContext {
32 AVFrame frame;
33 int width, height;
34 int nb_planes;
35 } PicContext;
36
37 static void picmemset_8bpp(PicContext *s, int value, int run, int *x, int *y)
38 {
39 while (run > 0) {
40 uint8_t *d = s->frame.data[0] + *y * s->frame.linesize[0];
41 if (*x + run >= s->width) {
42 int n = s->width - *x;
43 memset(d + *x, value, n);
44 run -= n;
45 *x = 0;
46 *y -= 1;
47 if (*y < 0)
48 break;
49 } else {
50 memset(d + *x, value, run);
51 *x += run;
52 break;
53 }
54 }
55 }
56
57 static void picmemset(PicContext *s, int value, int run, int *x, int *y, int *plane, int bits_per_plane)
58 {
59 uint8_t *d;
60 int shift = *plane * bits_per_plane;
61 int mask = ((1 << bits_per_plane) - 1) << shift;
62 value <<= shift;
63
64 while (run > 0) {
65 int j;
66 for (j = 8-bits_per_plane; j >= 0; j -= bits_per_plane) {
67 d = s->frame.data[0] + *y * s->frame.linesize[0];
68 d[*x] |= (value >> j) & mask;
69 *x += 1;
70 if (*x == s->width) {
71 *y -= 1;
72 *x = 0;
73 if (*y < 0) {
74 *y = s->height - 1;
75 *plane += 1;
76 value <<= bits_per_plane;
77 mask <<= bits_per_plane;
78 if (*plane >= s->nb_planes)
79 break;
80 }
81 }
82 }
83 run--;
84 }
85 }
86
87 static const uint8_t cga_mode45_index[6][4] = {
88 [0] = { 0, 3, 5, 7 }, // mode4, palette#1, low intensity
89 [1] = { 0, 2, 4, 6 }, // mode4, palette#2, low intensity
90 [2] = { 0, 3, 4, 7 }, // mode5, low intensity
91 [3] = { 0, 11, 13, 15 }, // mode4, palette#1, high intensity
92 [4] = { 0, 10, 12, 14 }, // mode4, palette#2, high intensity
93 [5] = { 0, 11, 12, 15 }, // mode5, high intensity
94 };
95
96 static int decode_frame(AVCodecContext *avctx,
97 void *data, int *data_size,
98 AVPacket *avpkt)
99 {
100 PicContext *s = avctx->priv_data;
101 int buf_size = avpkt->size;
102 const uint8_t *buf = avpkt->data;
103 const uint8_t *buf_end = avpkt->data + buf_size;
104 uint32_t *palette;
105 int bits_per_plane, bpp, etype, esize, npal;
106 int i, x, y, plane;
107
108 if (buf_size < 11)
109 return AVERROR_INVALIDDATA;
110
111 if (bytestream_get_le16(&buf) != 0x1234)
112 return AVERROR_INVALIDDATA;
113 s->width = bytestream_get_le16(&buf);
114 s->height = bytestream_get_le16(&buf);
115 buf += 4;
116 bits_per_plane = *buf & 0xF;
117 s->nb_planes = (*buf++ >> 4) + 1;
118 bpp = s->nb_planes ? bits_per_plane*s->nb_planes : bits_per_plane;
119 if (bits_per_plane > 8 || bpp < 1 || bpp > 32) {
120 av_log_ask_for_sample(s, "unsupported bit depth\n");
121 return AVERROR_INVALIDDATA;
122 }
123
124 if (*buf == 0xFF) {
125 buf += 2;
126 etype = bytestream_get_le16(&buf);
127 esize = bytestream_get_le16(&buf);
128 if (buf_end - buf < esize)
129 return AVERROR_INVALIDDATA;
130 } else {
131 etype = -1;
132 esize = 0;
133 }
134
135 avctx->pix_fmt = PIX_FMT_PAL8;
136
137 if (s->width != avctx->width && s->height != avctx->height) {
138 if (avcodec_check_dimensions(avctx, s->width, s->height) < 0)
139 return -1;
140 avcodec_set_dimensions(avctx, s->width, s->height);
141 if (s->frame.data[0])
142 avctx->release_buffer(avctx, &s->frame);
143 }
144
145 if (avctx->get_buffer(avctx, &s->frame) < 0){
146 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
147 return -1;
148 }
149 memset(s->frame.data[0], 0, s->height * s->frame.linesize[0]);
150 s->frame.pict_type = FF_I_TYPE;
151 s->frame.palette_has_changed = 1;
152
153 palette = (uint32_t*)s->frame.data[1];
154 if (etype == 1 && esize > 1 && *buf < 6) {
155 int idx = *buf;
156 npal = 4;
157 for (i = 0; i < npal; i++)
158 palette[i] = ff_cga_palette[ cga_mode45_index[idx][i] ];
159 } else if (etype == 2) {
160 npal = FFMIN(esize, 16);
161 for (i = 0; i < npal; i++)
162 palette[i] = ff_cga_palette[ FFMIN(buf[i], 16)];
163 } else if (etype == 3) {
164 npal = FFMIN(esize, 16);
165 for (i = 0; i < npal; i++)
166 palette[i] = ff_ega_palette[ FFMIN(buf[i], 63)];
167 } else if (etype == 4 || etype == 5) {
168 npal = FFMIN(esize / 3, 256);
169 for (i = 0; i < npal; i++)
170 palette[i] = AV_RB24(buf + i*3) << 2;
171 } else {
172 if (bpp == 1) {
173 npal = 2;
174 palette[0] = 0x000000;
175 palette[1] = 0xFFFFFF;
176 } else if (bpp == 2) {
177 npal = 4;
178 for (i = 0; i < npal; i++)
179 palette[i] = ff_cga_palette[ cga_mode45_index[0][i] ];
180 } else {
181 npal = 16;
182 memcpy(palette, ff_cga_palette, npal * 4);
183 }
184 }
185 // fill remaining palette entries
186 memset(palette + npal, 0, AVPALETTE_SIZE - npal * 4);
187 buf += esize;
188
189
190 x = 0;
191 y = s->height - 1;
192 plane = 0;
193 if (bytestream_get_le16(&buf)) {
194 while (buf_end - buf >= 6) {
195 const uint8_t *buf_pend = buf + FFMIN(AV_RL16(buf), buf_end - buf);
196 //ignore uncompressed block size reported at buf[2]
197 int marker = buf[4];
198 buf += 5;
199
200 while (plane < s->nb_planes && buf_pend - buf >= 1) {
201 int run = 1;
202 int val = *buf++;
203 if (val == marker) {
204 run = *buf++;
205 if (run == 0)
206 run = bytestream_get_le16(&buf);
207 val = *buf++;
208 }
209 if (buf > buf_end)
210 break;
211
212 if (bits_per_plane == 8) {
213 picmemset_8bpp(s, val, run, &x, &y);
214 if (y < 0)
215 break;
216 } else {
217 picmemset(s, val, run, &x, &y, &plane, bits_per_plane);
218 }
219 }
220 }
221 } else {
222 av_log_ask_for_sample(s, "uncompressed image\n");
223 return buf_size;
224 }
225
226 *data_size = sizeof(AVFrame);
227 *(AVFrame*)data = s->frame;
228 return buf_size;
229 }
230
231 static av_cold int decode_end(AVCodecContext *avctx)
232 {
233 PicContext *s = avctx->priv_data;
234 if (s->frame.data[0])
235 avctx->release_buffer(avctx, &s->frame);
236 return 0;
237 }
238
239 AVCodec pictor_decoder = {
240 "pictor",
241 CODEC_TYPE_VIDEO,
242 CODEC_ID_PICTOR,
243 sizeof(PicContext),
244 NULL,
245 NULL,
246 decode_end,
247 decode_frame,
248 CODEC_CAP_DR1,
249 .long_name = NULL_IF_CONFIG_SMALL("Pictor/PC Paint"),
250 };