2 * DVB subtitle encoding for ffmpeg
3 * Copyright (c) 2005 Fabrice Bellard.
5 * This file is part of FFmpeg.
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.
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.
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
22 #include "bytestream.h"
24 typedef struct DVBSubtitleContext {
29 #define PUTBITS2(val)\
31 bitbuf |= (val) << bitcnt;\
40 static void dvb_encode_rle2(uint8_t **pq,
41 const uint8_t *bitmap, int linesize,
47 int x, y, len, x1, v, color;
51 for(y = 0; y < h; y++) {
60 while (x1 < w && bitmap[x1] == color)
63 if (color == 0 && len == 2) {
67 } else if (len >= 3 && len <= 10) {
70 PUTBITS2((v >> 2) | 2);
73 } else if (len >= 12 && len <= 27) {
81 } else if (len >= 29) {
82 /* length = 29 ... 284 */
90 PUTBITS2((v >> 4) & 3);
91 PUTBITS2((v >> 2) & 3);
116 #define PUTBITS4(val)\
118 bitbuf |= (val) << bitcnt;\
127 /* some DVB decoders only implement 4 bits/pixel */
128 static void dvb_encode_rle4(uint8_t **pq,
129 const uint8_t *bitmap, int linesize,
135 int x, y, len, x1, v, color;
139 for(y = 0; y < h; y++) {
147 color = bitmap[x1++];
148 while (x1 < w && bitmap[x1] == color)
151 if (color == 0 && len == 2) {
154 } else if (color == 0 && (len >= 3 && len <= 9)) {
157 } else if (len >= 4 && len <= 7) {
159 PUTBITS4(8 + len - 4);
161 } else if (len >= 9 && len <= 24) {
166 } else if (len >= 25) {
197 #define ONE_HALF (1 << (SCALEBITS - 1))
198 #define FIX(x) ((int) ((x) * (1<<SCALEBITS) + 0.5))
200 #define RGB_TO_Y_CCIR(r, g, b) \
201 ((FIX(0.29900*219.0/255.0) * (r) + FIX(0.58700*219.0/255.0) * (g) + \
202 FIX(0.11400*219.0/255.0) * (b) + (ONE_HALF + (16 << SCALEBITS))) >> SCALEBITS)
204 #define RGB_TO_U_CCIR(r1, g1, b1, shift)\
205 (((- FIX(0.16874*224.0/255.0) * r1 - FIX(0.33126*224.0/255.0) * g1 + \
206 FIX(0.50000*224.0/255.0) * b1 + (ONE_HALF << shift) - 1) >> (SCALEBITS + shift)) + 128)
208 #define RGB_TO_V_CCIR(r1, g1, b1, shift)\
209 (((FIX(0.50000*224.0/255.0) * r1 - FIX(0.41869*224.0/255.0) * g1 - \
210 FIX(0.08131*224.0/255.0) * b1 + (ONE_HALF << shift) - 1) >> (SCALEBITS + shift)) + 128)
212 static int encode_dvb_subtitles(DVBSubtitleContext *s,
213 uint8_t *outbuf, AVSubtitle *h)
215 uint8_t *q, *pseg_len;
216 int page_id, region_id, clut_id, object_id, i, bpp_index, page_state;
223 if (h->num_rects == 0 || h->rects == NULL)
226 *q++ = 0x00; /* subtitle_stream_id */
228 /* page composition segment */
230 *q++ = 0x0f; /* sync_byte */
231 *q++ = 0x10; /* segment_type */
232 bytestream_put_be16(&q, page_id);
234 q += 2; /* segment length */
235 *q++ = 30; /* page_timeout (seconds) */
237 page_state = 0; /* normal case */
239 page_state = 2; /* mode change */
240 /* page_version = 0 + page_state */
241 *q++ = s->object_version | (page_state << 2) | 3;
243 for (region_id = 0; region_id < h->num_rects; region_id++) {
245 *q++ = 0xff; /* reserved */
246 bytestream_put_be16(&q, h->rects[region_id].x); /* left pos */
247 bytestream_put_be16(&q, h->rects[region_id].y); /* top pos */
250 bytestream_put_be16(&pseg_len, q - pseg_len - 2);
252 if (!s->hide_state) {
253 for (clut_id = 0; clut_id < h->num_rects; clut_id++) {
257 if (h->rects[clut_id].nb_colors <= 4) {
258 /* 2 bpp, some decoders do not support it correctly */
260 } else if (h->rects[clut_id].nb_colors <= 16) {
261 /* 4 bpp, standard encoding */
267 *q++ = 0x0f; /* sync byte */
268 *q++ = 0x12; /* CLUT definition segment */
269 bytestream_put_be16(&q, page_id);
271 q += 2; /* segment length */
273 *q++ = (0 << 4) | 0xf; /* version = 0 */
275 for(i = 0; i < h->rects[clut_id].nb_colors; i++) {
276 *q++ = i; /* clut_entry_id */
277 *q++ = (1 << (7 - bpp_index)) | (0xf << 1) | 1; /* 2 bits/pixel full range */
280 a = (h->rects[clut_id].rgba_palette[i] >> 24) & 0xff;
281 r = (h->rects[clut_id].rgba_palette[i] >> 16) & 0xff;
282 g = (h->rects[clut_id].rgba_palette[i] >> 8) & 0xff;
283 b = (h->rects[clut_id].rgba_palette[i] >> 0) & 0xff;
285 *q++ = RGB_TO_Y_CCIR(r, g, b);
286 *q++ = RGB_TO_V_CCIR(r, g, b, 0);
287 *q++ = RGB_TO_U_CCIR(r, g, b, 0);
292 bytestream_put_be16(&pseg_len, q - pseg_len - 2);
296 for (region_id = 0; region_id < h->num_rects; region_id++) {
298 /* region composition segment */
300 if (h->rects[region_id].nb_colors <= 4) {
301 /* 2 bpp, some decoders do not support it correctly */
303 } else if (h->rects[region_id].nb_colors <= 16) {
304 /* 4 bpp, standard encoding */
310 *q++ = 0x0f; /* sync_byte */
311 *q++ = 0x11; /* segment_type */
312 bytestream_put_be16(&q, page_id);
314 q += 2; /* segment length */
316 *q++ = (s->object_version << 4) | (0 << 3) | 0x07; /* version , no fill */
317 bytestream_put_be16(&q, h->rects[region_id].w); /* region width */
318 bytestream_put_be16(&q, h->rects[region_id].h); /* region height */
319 *q++ = ((1 + bpp_index) << 5) | ((1 + bpp_index) << 2) | 0x03;
320 *q++ = region_id; /* clut_id == region_id */
321 *q++ = 0; /* 8 bit fill colors */
322 *q++ = 0x03; /* 4 bit and 2 bit fill colors */
324 if (!s->hide_state) {
325 bytestream_put_be16(&q, region_id); /* object_id == region_id */
326 *q++ = (0 << 6) | (0 << 4);
332 bytestream_put_be16(&pseg_len, q - pseg_len - 2);
335 if (!s->hide_state) {
337 for (object_id = 0; object_id < h->num_rects; object_id++) {
338 /* Object Data segment */
340 if (h->rects[object_id].nb_colors <= 4) {
341 /* 2 bpp, some decoders do not support it correctly */
343 } else if (h->rects[object_id].nb_colors <= 16) {
344 /* 4 bpp, standard encoding */
350 *q++ = 0x0f; /* sync byte */
352 bytestream_put_be16(&q, page_id);
354 q += 2; /* segment length */
356 bytestream_put_be16(&q, object_id);
357 *q++ = (s->object_version << 4) | (0 << 2) | (0 << 1) | 1; /* version = 0,
358 onject_coding_method,
359 non_modifying_color_flag */
361 uint8_t *ptop_field_len, *pbottom_field_len, *top_ptr, *bottom_ptr;
362 void (*dvb_encode_rle)(uint8_t **pq,
363 const uint8_t *bitmap, int linesize,
367 pbottom_field_len = q;
371 dvb_encode_rle = dvb_encode_rle2;
373 dvb_encode_rle = dvb_encode_rle4;
376 dvb_encode_rle(&q, h->rects[object_id].bitmap, h->rects[object_id].w * 2,
377 h->rects[object_id].w, h->rects[object_id].h >> 1);
379 dvb_encode_rle(&q, h->rects[object_id].bitmap + h->rects[object_id].w,
380 h->rects[object_id].w * 2, h->rects[object_id].w,
381 h->rects[object_id].h >> 1);
383 bytestream_put_be16(&ptop_field_len, bottom_ptr - top_ptr);
384 bytestream_put_be16(&pbottom_field_len, q - bottom_ptr);
387 bytestream_put_be16(&pseg_len, q - pseg_len - 2);
391 /* end of display set segment */
393 *q++ = 0x0f; /* sync_byte */
394 *q++ = 0x80; /* segment_type */
395 bytestream_put_be16(&q, page_id);
397 q += 2; /* segment length */
399 bytestream_put_be16(&pseg_len, q - pseg_len - 2);
401 *q++ = 0xff; /* end of PES data */
403 s->object_version = (s->object_version + 1) & 0xf;
404 s->hide_state = !s->hide_state;
408 static int dvbsub_init_decoder(AVCodecContext *avctx)
413 static int dvbsub_close_decoder(AVCodecContext *avctx)
418 static int dvbsub_encode(AVCodecContext *avctx,
419 unsigned char *buf, int buf_size, void *data)
421 DVBSubtitleContext *s = avctx->priv_data;
422 AVSubtitle *sub = data;
425 ret = encode_dvb_subtitles(s, buf, sub);
429 AVCodec dvbsub_encoder = {
432 CODEC_ID_DVB_SUBTITLE,
433 sizeof(DVBSubtitleContext),
436 dvbsub_close_decoder,