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
24 * Pictor/PC Paint decoder
25 */
26
27 #include "libavutil/imgutils.h"
28 #include "avcodec.h"
29 #include "bytestream.h"
30 #include "cga_data.h"
31 #include "codec_internal.h"
32 #include "internal.h"
33
34 typedef struct PicContext {
35 int width, height;
36 int nb_planes;
37 GetByteContext g;
38 } PicContext;
39
picmemset_8bpp(PicContext * s,AVFrame * frame,int value,int run,int * x,int * y)40 static void picmemset_8bpp(PicContext *s, AVFrame *frame, int value, int run,
41 int *x, int *y)
42 {
43 while (run > 0) {
44 uint8_t *d = frame->data[0] + *y * frame->linesize[0];
45 if (*x + run >= s->width) {
46 int n = s->width - *x;
47 memset(d + *x, value, n);
48 run -= n;
49 *x = 0;
50 *y -= 1;
51 if (*y < 0)
52 break;
53 } else {
54 memset(d + *x, value, run);
55 *x += run;
56 break;
57 }
58 }
59 }
60
picmemset(PicContext * s,AVFrame * frame,unsigned value,int run,int * x,int * y,int * plane,int bits_per_plane)61 static void picmemset(PicContext *s, AVFrame *frame, unsigned value, int run,
62 int *x, int *y, int *plane, int bits_per_plane)
63 {
64 uint8_t *d;
65 int shift = *plane * bits_per_plane;
66 unsigned mask = ((1U << bits_per_plane) - 1) << shift;
67 int xl = *x;
68 int yl = *y;
69 int planel = *plane;
70 int pixels_per_value = 8/bits_per_plane;
71 value <<= shift;
72
73 d = frame->data[0] + yl * frame->linesize[0];
74 while (run > 0) {
75 int j;
76 for (j = 8-bits_per_plane; j >= 0; j -= bits_per_plane) {
77 d[xl] |= (value >> j) & mask;
78 xl += 1;
79 while (xl == s->width) {
80 yl -= 1;
81 xl = 0;
82 if (yl < 0) {
83 yl = s->height - 1;
84 planel += 1;
85 if (planel >= s->nb_planes)
86 goto end;
87 value <<= bits_per_plane;
88 mask <<= bits_per_plane;
89 }
90 d = frame->data[0] + yl * frame->linesize[0];
91 if (s->nb_planes == 1 &&
92 run*pixels_per_value >= s->width &&
93 pixels_per_value < (s->width / pixels_per_value * pixels_per_value)
94 ) {
95 for (; xl < pixels_per_value; xl ++) {
96 j = (j < bits_per_plane ? 8 : j) - bits_per_plane;
97 d[xl] |= (value >> j) & mask;
98 }
99 av_memcpy_backptr(d+xl, pixels_per_value, s->width - xl);
100 run -= s->width / pixels_per_value;
101 xl = s->width / pixels_per_value * pixels_per_value;
102 }
103 }
104 }
105 run--;
106 }
107 end:
108 *x = xl;
109 *y = yl;
110 *plane = planel;
111 }
112
113 static const uint8_t cga_mode45_index[6][4] = {
114 [0] = { 0, 3, 5, 7 }, // mode4, palette#1, low intensity
115 [1] = { 0, 2, 4, 6 }, // mode4, palette#2, low intensity
116 [2] = { 0, 3, 4, 7 }, // mode5, low intensity
117 [3] = { 0, 11, 13, 15 }, // mode4, palette#1, high intensity
118 [4] = { 0, 10, 12, 14 }, // mode4, palette#2, high intensity
119 [5] = { 0, 11, 12, 15 }, // mode5, high intensity
120 };
121
decode_frame(AVCodecContext * avctx,AVFrame * frame,int * got_frame,AVPacket * avpkt)122 static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
123 int *got_frame, AVPacket *avpkt)
124 {
125 PicContext *s = avctx->priv_data;
126 uint32_t *palette;
127 int bits_per_plane, bpp, etype, esize, npal, pos_after_pal;
128 int i, x, y, plane, tmp, ret, val;
129
130 bytestream2_init(&s->g, avpkt->data, avpkt->size);
131
132 if (bytestream2_get_bytes_left(&s->g) < 11)
133 return AVERROR_INVALIDDATA;
134
135 if (bytestream2_get_le16u(&s->g) != 0x1234)
136 return AVERROR_INVALIDDATA;
137
138 s->width = bytestream2_get_le16u(&s->g);
139 s->height = bytestream2_get_le16u(&s->g);
140 bytestream2_skip(&s->g, 4);
141 tmp = bytestream2_get_byteu(&s->g);
142 bits_per_plane = tmp & 0xF;
143 s->nb_planes = (tmp >> 4) + 1;
144 bpp = bits_per_plane * s->nb_planes;
145 if (bits_per_plane > 8 || bpp < 1 || bpp > 32) {
146 avpriv_request_sample(avctx, "Unsupported bit depth");
147 return AVERROR_PATCHWELCOME;
148 }
149
150 if (bytestream2_peek_byte(&s->g) == 0xFF || bpp == 1 || bpp == 4 || bpp == 8) {
151 bytestream2_skip(&s->g, 2);
152 etype = bytestream2_get_le16(&s->g);
153 esize = bytestream2_get_le16(&s->g);
154 if (bytestream2_get_bytes_left(&s->g) < esize)
155 return AVERROR_INVALIDDATA;
156 } else {
157 etype = -1;
158 esize = 0;
159 }
160
161 avctx->pix_fmt = AV_PIX_FMT_PAL8;
162
163 if (av_image_check_size(s->width, s->height, 0, avctx) < 0)
164 return -1;
165 if (s->width != avctx->width || s->height != avctx->height) {
166 ret = ff_set_dimensions(avctx, s->width, s->height);
167 if (ret < 0)
168 return ret;
169 }
170
171 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
172 return ret;
173 memset(frame->data[0], 0, s->height * frame->linesize[0]);
174 frame->pict_type = AV_PICTURE_TYPE_I;
175 frame->palette_has_changed = 1;
176
177 pos_after_pal = bytestream2_tell(&s->g) + esize;
178 palette = (uint32_t*)frame->data[1];
179 if (etype == 1 && esize > 1 && bytestream2_peek_byte(&s->g) < 6) {
180 int idx = bytestream2_get_byte(&s->g);
181 npal = 4;
182 for (i = 0; i < npal; i++)
183 palette[i] = ff_cga_palette[ cga_mode45_index[idx][i] ];
184 } else if (etype == 2) {
185 npal = FFMIN(esize, 16);
186 for (i = 0; i < npal; i++) {
187 int pal_idx = bytestream2_get_byte(&s->g);
188 palette[i] = ff_cga_palette[FFMIN(pal_idx, 15)];
189 }
190 } else if (etype == 3) {
191 npal = FFMIN(esize, 16);
192 for (i = 0; i < npal; i++) {
193 int pal_idx = bytestream2_get_byte(&s->g);
194 palette[i] = ff_ega_palette[FFMIN(pal_idx, 63)];
195 }
196 } else if (etype == 4 || etype == 5) {
197 npal = FFMIN(esize / 3, 256);
198 for (i = 0; i < npal; i++) {
199 palette[i] = bytestream2_get_be24(&s->g) << 2;
200 palette[i] |= 0xFFU << 24 | palette[i] >> 6 & 0x30303;
201 }
202 } else {
203 if (bpp == 1) {
204 npal = 2;
205 palette[0] = 0xFF000000;
206 palette[1] = 0xFFFFFFFF;
207 } else if (bpp == 2) {
208 npal = 4;
209 for (i = 0; i < npal; i++)
210 palette[i] = ff_cga_palette[ cga_mode45_index[0][i] ];
211 } else {
212 npal = 16;
213 memcpy(palette, ff_cga_palette, npal * 4);
214 }
215 }
216 // fill remaining palette entries
217 memset(palette + npal, 0, AVPALETTE_SIZE - npal * 4);
218 // skip remaining palette bytes
219 bytestream2_seek(&s->g, pos_after_pal, SEEK_SET);
220
221 val = 0;
222 y = s->height - 1;
223 if (bytestream2_get_le16(&s->g)) {
224 x = 0;
225 plane = 0;
226 while (bytestream2_get_bytes_left(&s->g) >= 6) {
227 int stop_size, marker, t1, t2;
228
229 t1 = bytestream2_get_bytes_left(&s->g);
230 t2 = bytestream2_get_le16(&s->g);
231 stop_size = t1 - FFMIN(t1, t2);
232 // ignore uncompressed block size
233 bytestream2_skip(&s->g, 2);
234 marker = bytestream2_get_byte(&s->g);
235
236 while (plane < s->nb_planes &&
237 bytestream2_get_bytes_left(&s->g) > stop_size) {
238 int run = 1;
239 val = bytestream2_get_byte(&s->g);
240 if (val == marker) {
241 run = bytestream2_get_byte(&s->g);
242 if (run == 0)
243 run = bytestream2_get_le16(&s->g);
244 val = bytestream2_get_byte(&s->g);
245 }
246
247 if (bits_per_plane == 8) {
248 picmemset_8bpp(s, frame, val, run, &x, &y);
249 if (y < 0)
250 goto finish;
251 } else {
252 picmemset(s, frame, val, run, &x, &y, &plane, bits_per_plane);
253 }
254 }
255 }
256
257 if (s->nb_planes - plane > 1)
258 return AVERROR_INVALIDDATA;
259
260 if (plane < s->nb_planes && x < avctx->width) {
261 int run = (y + 1) * avctx->width - x;
262 if (bits_per_plane == 8)
263 picmemset_8bpp(s, frame, val, run, &x, &y);
264 else
265 picmemset(s, frame, val, run / (8 / bits_per_plane), &x, &y, &plane, bits_per_plane);
266 }
267 } else {
268 while (y >= 0 && bytestream2_get_bytes_left(&s->g) > 0) {
269 memcpy(frame->data[0] + y * frame->linesize[0], s->g.buffer, FFMIN(avctx->width, bytestream2_get_bytes_left(&s->g)));
270 bytestream2_skip(&s->g, avctx->width);
271 y--;
272 }
273 }
274 finish:
275
276 *got_frame = 1;
277 return avpkt->size;
278 }
279
280 const FFCodec ff_pictor_decoder = {
281 .p.name = "pictor",
282 .p.long_name = NULL_IF_CONFIG_SMALL("Pictor/PC Paint"),
283 .p.type = AVMEDIA_TYPE_VIDEO,
284 .p.id = AV_CODEC_ID_PICTOR,
285 .p.capabilities = AV_CODEC_CAP_DR1,
286 .priv_data_size = sizeof(PicContext),
287 FF_CODEC_DECODE_CB(decode_frame),
288 };
289