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,