2 * DVB subtitle encoding for ffmpeg
3 * Copyright (c) 2005 Fabrice Bellard.
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.
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.
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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 typedef struct DVBSubtitleContext {
26 #define PUTBITS2(val)\
28 bitbuf |= (val) << bitcnt;\
37 static void dvb_encode_rle2(uint8_t **pq,
38 const uint8_t *bitmap, int linesize,
44 int x, y, len, x1, v, color;
48 for(y = 0; y < h; y++) {
57 while (x1 < w && bitmap[x1] == color)
60 if (color == 0 && len == 2) {
64 } else if (len >= 3 && len <= 10) {
67 PUTBITS2((v >> 2) | 2);
70 } else if (len >= 12 && len <= 27) {
78 } else if (len >= 29) {
79 /* length = 29 ... 284 */
87 PUTBITS2((v >> 4) & 3);
88 PUTBITS2((v >> 2) & 3);
113 #define PUTBITS4(val)\
115 bitbuf |= (val) << bitcnt;\
124 /* some DVB decoders only implement 4 bits/pixel */
125 static void dvb_encode_rle4(uint8_t **pq,
126 const uint8_t *bitmap, int linesize,
132 int x, y, len, x1, v, color;
136 for(y = 0; y < h; y++) {
144 color = bitmap[x1++];
145 while (x1 < w && bitmap[x1] == color)
148 if (color == 0 && len == 2) {
151 } else if (color == 0 && (len >= 3 && len <= 9)) {
154 } else if (len >= 4 && len <= 7) {
156 PUTBITS4(8 + len - 4);
158 } else if (len >= 9 && len <= 24) {
163 } else if (len >= 25) {
194 #define ONE_HALF (1 << (SCALEBITS - 1))
195 #define FIX(x) ((int) ((x) * (1<<SCALEBITS) + 0.5))
197 #define RGB_TO_Y_CCIR(r, g, b) \
198 ((FIX(0.29900*219.0/255.0) * (r) + FIX(0.58700*219.0/255.0) * (g) + \
199 FIX(0.11400*219.0/255.0) * (b) + (ONE_HALF + (16 << SCALEBITS))) >> SCALEBITS)
201 #define RGB_TO_U_CCIR(r1, g1, b1, shift)\
202 (((- FIX(0.16874*224.0/255.0) * r1 - FIX(0.33126*224.0/255.0) * g1 + \
203 FIX(0.50000*224.0/255.0) * b1 + (ONE_HALF << shift) - 1) >> (SCALEBITS + shift)) + 128)
205 #define RGB_TO_V_CCIR(r1, g1, b1, shift)\
206 (((FIX(0.50000*224.0/255.0) * r1 - FIX(0.41869*224.0/255.0) * g1 - \
207 FIX(0.08131*224.0/255.0) * b1 + (ONE_HALF << shift) - 1) >> (SCALEBITS + shift)) + 128)
209 static inline void putbe16(uint8_t **pq, uint16_t v)
218 static int encode_dvb_subtitles(DVBSubtitleContext *s,
219 uint8_t *outbuf, AVSubtitle *h)
221 uint8_t *q, *pseg_len;
222 int page_id, region_id, clut_id, object_id, i, bpp_index, page_state;
229 if (h->num_rects == 0 || h->rects == NULL)
232 *q++ = 0x00; /* subtitle_stream_id */
234 /* page composition segment */
236 *q++ = 0x0f; /* sync_byte */
237 *q++ = 0x10; /* segment_type */
238 putbe16(&q, page_id);
240 q += 2; /* segment length */
241 *q++ = 30; /* page_timeout (seconds) */
243 page_state = 0; /* normal case */
245 page_state = 2; /* mode change */
246 /* page_version = 0 + page_state */
247 *q++ = s->object_version | (page_state << 2) | 3;
249 for (region_id = 0; region_id < h->num_rects; region_id++) {
251 *q++ = 0xff; /* reserved */
252 putbe16(&q, h->rects[region_id].x); /* left pos */
253 putbe16(&q, h->rects[region_id].y); /* top pos */
256 putbe16(&pseg_len, q - pseg_len - 2);
258 if (!s->hide_state) {
259 for (clut_id = 0; clut_id < h->num_rects; clut_id++) {
263 if (h->rects[clut_id].nb_colors <= 4) {
264 /* 2 bpp, some decoders do not support it correctly */
266 } else if (h->rects[clut_id].nb_colors <= 16) {
267 /* 4 bpp, standard encoding */
273 *q++ = 0x0f; /* sync byte */
274 *q++ = 0x12; /* CLUT definition segment */
275 putbe16(&q, page_id);
277 q += 2; /* segment length */
279 *q++ = (0 << 4) | 0xf; /* version = 0 */
281 for(i = 0; i < h->rects[clut_id].nb_colors; i++) {
282 *q++ = i; /* clut_entry_id */
283 *q++ = (1 << (7 - bpp_index)) | (0xf << 1) | 1; /* 2 bits/pixel full range */
286 a = (h->rects[clut_id].rgba_palette[i] >> 24) & 0xff;
287 r = (h->rects[clut_id].rgba_palette[i] >> 16) & 0xff;
288 g = (h->rects[clut_id].rgba_palette[i] >> 8) & 0xff;
289 b = (h->rects[clut_id].rgba_palette[i] >> 0) & 0xff;
291 *q++ = RGB_TO_Y_CCIR(r, g, b);
292 *q++ = RGB_TO_V_CCIR(r, g, b, 0);
293 *q++ = RGB_TO_U_CCIR(r, g, b, 0);
298 putbe16(&pseg_len, q - pseg_len - 2);
302 for (region_id = 0; region_id < h->num_rects; region_id++) {
304 /* region composition segment */
306 if (h->rects[region_id].nb_colors <= 4) {
307 /* 2 bpp, some decoders do not support it correctly */
309 } else if (h->rects[region_id].nb_colors <= 16) {
310 /* 4 bpp, standard encoding */
316 *q++ = 0x0f; /* sync_byte */
317 *q++ = 0x11; /* segment_type */
318 putbe16(&q, page_id);
320 q += 2; /* segment length */
322 *q++ = (s->object_version << 4) | (0 << 3) | 0x07; /* version , no fill */
323 putbe16(&q, h->rects[region_id].w); /* region width */
324 putbe16(&q, h->rects[region_id].h); /* region height */
325 *q++ = ((1 + bpp_index) << 5) | ((1 + bpp_index) << 2) | 0x03;
326 *q++ = region_id; /* clut_id == region_id */
327 *q++ = 0; /* 8 bit fill colors */
328 *q++ = 0x03; /* 4 bit and 2 bit fill colors */
330 if (!s->hide_state) {
331 putbe16(&q, region_id); /* object_id == region_id */
332 *q++ = (0 << 6) | (0 << 4);
338 putbe16(&pseg_len, q - pseg_len - 2);
341 if (!s->hide_state) {
343 for (object_id = 0; object_id < h->num_rects; object_id++) {
344 /* Object Data segment */
346 if (h->rects[object_id].nb_colors <= 4) {
347 /* 2 bpp, some decoders do not support it correctly */
349 } else if (h->rects[object_id].nb_colors <= 16) {
350 /* 4 bpp, standard encoding */
356 *q++ = 0x0f; /* sync byte */
358 putbe16(&q, page_id);
360 q += 2; /* segment length */
362 putbe16(&q, object_id);
363 *q++ = (s->object_version << 4) | (0 << 2) | (0 << 1) | 1; /* version = 0,
364 onject_coding_method,
365 non_modifying_color_flag */
367 uint8_t *ptop_field_len, *pbottom_field_len, *top_ptr, *bottom_ptr;
368 void (*dvb_encode_rle)(uint8_t **pq,
369 const uint8_t *bitmap, int linesize,
373 pbottom_field_len = q;
377 dvb_encode_rle = dvb_encode_rle2;
379 dvb_encode_rle = dvb_encode_rle4;
382 dvb_encode_rle(&q, h->rects[object_id].bitmap, h->rects[object_id].w * 2,
383 h->rects[object_id].w, h->rects[object_id].h >> 1);
385 dvb_encode_rle(&q, h->rects[object_id].bitmap + h->rects[object_id].w,
386 h->rects[object_id].w * 2, h->rects[object_id].w,
387 h->rects[object_id].h >> 1);
389 putbe16(&ptop_field_len, bottom_ptr - top_ptr);
390 putbe16(&pbottom_field_len, q - bottom_ptr);
393 putbe16(&pseg_len, q - pseg_len - 2);
397 /* end of display set segment */
399 *q++ = 0x0f; /* sync_byte */
400 *q++ = 0x80; /* segment_type */
401 putbe16(&q, page_id);
403 q += 2; /* segment length */
405 putbe16(&pseg_len, q - pseg_len - 2);
407 *q++ = 0xff; /* end of PES data */
409 s->object_version = (s->object_version + 1) & 0xf;
410 s->hide_state = !s->hide_state;
414 static int dvbsub_init_decoder(AVCodecContext *avctx)
419 static int dvbsub_close_decoder(AVCodecContext *avctx)
424 static int dvbsub_encode(AVCodecContext *avctx,
425 unsigned char *buf, int buf_size, void *data)
427 DVBSubtitleContext *s = avctx->priv_data;
428 AVSubtitle *sub = data;
431 ret = encode_dvb_subtitles(s, buf, sub);
435 AVCodec dvbsub_encoder = {
438 CODEC_ID_DVB_SUBTITLE,
439 sizeof(DVBSubtitleContext),
442 dvbsub_close_decoder,