use PRIxN, %zd, %td formats where needed
[libav.git] / libavcodec / dvdsubenc.c
1 /*
2 * DVD subtitle encoding for ffmpeg
3 * Copyright (c) 2005 Wolfram Gloger.
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
14 *
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
19 #include "avcodec.h"
20
21 #undef NDEBUG
22 #include <assert.h>
23
24 typedef struct DVDSubtitleContext {
25 } DVDSubtitleContext;
26
27 // ncnt is the nibble counter
28 #define PUTNIBBLE(val)\
29 do {\
30 if (ncnt++ & 1)\
31 *q++ = bitbuf | ((val) & 0x0f);\
32 else\
33 bitbuf = (val) << 4;\
34 } while(0)
35
36 static void dvd_encode_rle(uint8_t **pq,
37 const uint8_t *bitmap, int linesize,
38 int w, int h,
39 const int cmap[256])
40 {
41 uint8_t *q;
42 unsigned int bitbuf = 0;
43 int ncnt;
44 int x, y, len, color;
45
46 q = *pq;
47
48 for (y = 0; y < h; ++y) {
49 ncnt = 0;
50 for(x = 0; x < w; x += len) {
51 color = bitmap[x];
52 for (len=1; x+len < w; ++len)
53 if (bitmap[x+len] != color)
54 break;
55 color = cmap[color];
56 assert(color < 4);
57 if (len < 0x04) {
58 PUTNIBBLE((len << 2)|color);
59 } else if (len < 0x10) {
60 PUTNIBBLE(len >> 2);
61 PUTNIBBLE((len << 2)|color);
62 } else if (len < 0x40) {
63 PUTNIBBLE(0);
64 PUTNIBBLE(len >> 2);
65 PUTNIBBLE((len << 2)|color);
66 } else if (x+len == w) {
67 PUTNIBBLE(0);
68 PUTNIBBLE(0);
69 PUTNIBBLE(0);
70 PUTNIBBLE(color);
71 } else {
72 if (len > 0xff)
73 len = 0xff;
74 PUTNIBBLE(0);
75 PUTNIBBLE(len >> 6);
76 PUTNIBBLE(len >> 2);
77 PUTNIBBLE((len << 2)|color);
78 }
79 }
80 /* end of line */
81 if (ncnt & 1)
82 PUTNIBBLE(0);
83 bitmap += linesize;
84 }
85
86 *pq = q;
87 }
88
89 static inline void putbe16(uint8_t **pq, uint16_t v)
90 {
91 uint8_t *q = *pq;
92 *q++ = v >> 8;
93 *q++ = v;
94 *pq = q;
95 }
96
97 static int encode_dvd_subtitles(uint8_t *outbuf, int outbuf_size,
98 const AVSubtitle *h)
99 {
100 uint8_t *q, *qq;
101 int object_id;
102 int offset1[20], offset2[20];
103 int i, imax, color, alpha, rects = h->num_rects;
104 unsigned long hmax;
105 unsigned long hist[256];
106 int cmap[256];
107
108 if (rects == 0 || h->rects == NULL)
109 return -1;
110 if (rects > 20)
111 rects = 20;
112
113 // analyze bitmaps, compress to 4 colors
114 for (i=0; i<256; ++i) {
115 hist[i] = 0;
116 cmap[i] = 0;
117 }
118 for (object_id = 0; object_id < rects; object_id++)
119 for (i=0; i<h->rects[object_id].w*h->rects[object_id].h; ++i) {
120 color = h->rects[object_id].bitmap[i];
121 // only count non-transparent pixels
122 alpha = h->rects[object_id].rgba_palette[color] >> 24;
123 hist[color] += alpha;
124 }
125 for (color=3;; --color) {
126 hmax = 0;
127 imax = 0;
128 for (i=0; i<256; ++i)
129 if (hist[i] > hmax) {
130 imax = i;
131 hmax = hist[i];
132 }
133 if (hmax == 0)
134 break;
135 if (color == 0)
136 color = 3;
137 av_log(NULL, AV_LOG_DEBUG, "dvd_subtitle hist[%d]=%ld -> col %d\n",
138 imax, hist[imax], color);
139 cmap[imax] = color;
140 hist[imax] = 0;
141 }
142
143
144 // encode data block
145 q = outbuf + 4;
146 for (object_id = 0; object_id < rects; object_id++) {
147 offset1[object_id] = q - outbuf;
148 // worst case memory requirement: 1 nibble per pixel..
149 if ((q - outbuf) + h->rects[object_id].w*h->rects[object_id].h/2
150 + 17*rects + 21 > outbuf_size) {
151 av_log(NULL, AV_LOG_ERROR, "dvd_subtitle too big\n");
152 return -1;
153 }
154 dvd_encode_rle(&q, h->rects[object_id].bitmap,
155 h->rects[object_id].w*2,
156 h->rects[object_id].w, h->rects[object_id].h >> 1,
157 cmap);
158 offset2[object_id] = q - outbuf;
159 dvd_encode_rle(&q, h->rects[object_id].bitmap + h->rects[object_id].w,
160 h->rects[object_id].w*2,
161 h->rects[object_id].w, h->rects[object_id].h >> 1,
162 cmap);
163 }
164
165 // set data packet size
166 qq = outbuf + 2;
167 putbe16(&qq, q - outbuf);
168
169 // send start display command
170 putbe16(&q, (h->start_display_time*90) >> 10);
171 putbe16(&q, (q - outbuf) /*- 2 */ + 8 + 12*rects + 2);
172 *q++ = 0x03; // palette - 4 nibbles
173 *q++ = 0x03; *q++ = 0x7f;
174 *q++ = 0x04; // alpha - 4 nibbles
175 *q++ = 0xf0; *q++ = 0x00;
176 //*q++ = 0x0f; *q++ = 0xff;
177
178 // XXX not sure if more than one rect can really be encoded..
179 // 12 bytes per rect
180 for (object_id = 0; object_id < rects; object_id++) {
181 int x2 = h->rects[object_id].x + h->rects[object_id].w - 1;
182 int y2 = h->rects[object_id].y + h->rects[object_id].h - 1;
183
184 *q++ = 0x05;
185 // x1 x2 -> 6 nibbles
186 *q++ = h->rects[object_id].x >> 4;
187 *q++ = (h->rects[object_id].x << 4) | ((x2 >> 8) & 0xf);
188 *q++ = x2;
189 // y1 y2 -> 6 nibbles
190 *q++ = h->rects[object_id].y >> 4;
191 *q++ = (h->rects[object_id].y << 4) | ((y2 >> 8) & 0xf);
192 *q++ = y2;
193
194 *q++ = 0x06;
195 // offset1, offset2
196 putbe16(&q, offset1[object_id]);
197 putbe16(&q, offset2[object_id]);
198 }
199 *q++ = 0x01; // start command
200 *q++ = 0xff; // terminating command
201
202 // send stop display command last
203 putbe16(&q, (h->end_display_time*90) >> 10);
204 putbe16(&q, (q - outbuf) - 2 /*+ 4*/);
205 *q++ = 0x02; // set end
206 *q++ = 0xff; // terminating command
207
208 qq = outbuf;
209 putbe16(&qq, q - outbuf);
210
211 av_log(NULL, AV_LOG_DEBUG, "subtitle_packet size=%td\n", q - outbuf);
212 return q - outbuf;
213 }
214
215 static int dvdsub_init_encoder(AVCodecContext *avctx)
216 {
217 return 0;
218 }
219
220 static int dvdsub_close_encoder(AVCodecContext *avctx)
221 {
222 return 0;
223 }
224
225 static int dvdsub_encode(AVCodecContext *avctx,
226 unsigned char *buf, int buf_size, void *data)
227 {
228 //DVDSubtitleContext *s = avctx->priv_data;
229 AVSubtitle *sub = data;
230 int ret;
231
232 ret = encode_dvd_subtitles(buf, buf_size, sub);
233 return ret;
234 }
235
236 AVCodec dvdsub_encoder = {
237 "dvdsub",
238 CODEC_TYPE_SUBTITLE,
239 CODEC_ID_DVD_SUBTITLE,
240 sizeof(DVDSubtitleContext),
241 dvdsub_init_encoder,
242 dvdsub_encode,
243 dvdsub_close_encoder,
244 };
245
246 /* Local Variables: */
247 /* c-basic-offset:4 */
248 /* End: */