summaryrefslogtreecommitdiff
path: root/libavcodec/dvbsubenc.c
diff options
context:
space:
mode:
Diffstat (limited to 'libavcodec/dvbsubenc.c')
-rw-r--r--libavcodec/dvbsubenc.c518
1 files changed, 518 insertions, 0 deletions
diff --git a/libavcodec/dvbsubenc.c b/libavcodec/dvbsubenc.c
new file mode 100644
index 0000000000..7b8ef41a7e
--- /dev/null
+++ b/libavcodec/dvbsubenc.c
@@ -0,0 +1,518 @@
+/*
+ * DVB subtitle encoding
+ * Copyright (c) 2005 Fabrice Bellard
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#include "avcodec.h"
+#include "bytestream.h"
+#include "libavutil/colorspace.h"
+
+typedef struct DVBSubtitleContext {
+ int object_version;
+} DVBSubtitleContext;
+
+#define PUTBITS2(val)\
+{\
+ bitbuf |= (val) << bitcnt;\
+ bitcnt -= 2;\
+ if (bitcnt < 0) {\
+ bitcnt = 6;\
+ *q++ = bitbuf;\
+ bitbuf = 0;\
+ }\
+}
+
+static int dvb_encode_rle2(uint8_t **pq, int buf_size,
+ const uint8_t *bitmap, int linesize,
+ int w, int h)
+{
+ uint8_t *q, *line_begin;
+ unsigned int bitbuf;
+ int bitcnt;
+ int x, y, len, x1, v, color;
+
+ q = *pq;
+
+ for(y = 0; y < h; y++) {
+ // Worst case line is 3 bits per value + 4 bytes overhead
+ if (buf_size * 8 < w * 3 + 32)
+ return AVERROR_BUFFER_TOO_SMALL;
+ line_begin = q;
+ *q++ = 0x10;
+ bitbuf = 0;
+ bitcnt = 6;
+
+ x = 0;
+ while (x < w) {
+ x1 = x;
+ color = bitmap[x1++];
+ while (x1 < w && bitmap[x1] == color)
+ x1++;
+ len = x1 - x;
+ if (color == 0 && len == 2) {
+ PUTBITS2(0);
+ PUTBITS2(0);
+ PUTBITS2(1);
+ } else if (len >= 3 && len <= 10) {
+ v = len - 3;
+ PUTBITS2(0);
+ PUTBITS2((v >> 2) | 2);
+ PUTBITS2(v & 3);
+ PUTBITS2(color);
+ } else if (len >= 12 && len <= 27) {
+ v = len - 12;
+ PUTBITS2(0);
+ PUTBITS2(0);
+ PUTBITS2(2);
+ PUTBITS2(v >> 2);
+ PUTBITS2(v & 3);
+ PUTBITS2(color);
+ } else if (len >= 29) {
+ /* length = 29 ... 284 */
+ if (len > 284)
+ len = 284;
+ v = len - 29;
+ PUTBITS2(0);
+ PUTBITS2(0);
+ PUTBITS2(3);
+ PUTBITS2((v >> 6));
+ PUTBITS2((v >> 4) & 3);
+ PUTBITS2((v >> 2) & 3);
+ PUTBITS2(v & 3);
+ PUTBITS2(color);
+ } else {
+ PUTBITS2(color);
+ if (color == 0) {
+ PUTBITS2(1);
+ }
+ len = 1;
+ }
+ x += len;
+ }
+ /* end of line */
+ PUTBITS2(0);
+ PUTBITS2(0);
+ PUTBITS2(0);
+ if (bitcnt != 6) {
+ *q++ = bitbuf;
+ }
+ *q++ = 0xf0;
+ bitmap += linesize;
+ buf_size -= q - line_begin;
+ }
+ len = q - *pq;
+ *pq = q;
+ return len;
+}
+
+#define PUTBITS4(val)\
+{\
+ bitbuf |= (val) << bitcnt;\
+ bitcnt -= 4;\
+ if (bitcnt < 0) {\
+ bitcnt = 4;\
+ *q++ = bitbuf;\
+ bitbuf = 0;\
+ }\
+}
+
+/* some DVB decoders only implement 4 bits/pixel */
+static int dvb_encode_rle4(uint8_t **pq, int buf_size,
+ const uint8_t *bitmap, int linesize,
+ int w, int h)
+{
+ uint8_t *q, *line_begin;
+ unsigned int bitbuf;
+ int bitcnt;
+ int x, y, len, x1, v, color;
+
+ q = *pq;
+
+ for(y = 0; y < h; y++) {
+ // Worst case line is 6 bits per value, + 4 bytes overhead
+ if (buf_size * 8 < w * 6 + 32)
+ return AVERROR_BUFFER_TOO_SMALL;
+ line_begin = q;
+ *q++ = 0x11;
+ bitbuf = 0;
+ bitcnt = 4;
+
+ x = 0;
+ while (x < w) {
+ x1 = x;
+ color = bitmap[x1++];
+ while (x1 < w && bitmap[x1] == color)
+ x1++;
+ len = x1 - x;
+ if (color == 0 && len == 2) {
+ PUTBITS4(0);
+ PUTBITS4(0xd);
+ } else if (color == 0 && (len >= 3 && len <= 9)) {
+ PUTBITS4(0);
+ PUTBITS4(len - 2);
+ } else if (len >= 4 && len <= 7) {
+ PUTBITS4(0);
+ PUTBITS4(8 + len - 4);
+ PUTBITS4(color);
+ } else if (len >= 9 && len <= 24) {
+ PUTBITS4(0);
+ PUTBITS4(0xe);
+ PUTBITS4(len - 9);
+ PUTBITS4(color);
+ } else if (len >= 25) {
+ if (len > 280)
+ len = 280;
+ v = len - 25;
+ PUTBITS4(0);
+ PUTBITS4(0xf);
+ PUTBITS4(v >> 4);
+ PUTBITS4(v & 0xf);
+ PUTBITS4(color);
+ } else {
+ PUTBITS4(color);
+ if (color == 0) {
+ PUTBITS4(0xc);
+ }
+ len = 1;
+ }
+ x += len;
+ }
+ /* end of line */
+ PUTBITS4(0);
+ PUTBITS4(0);
+ if (bitcnt != 4) {
+ *q++ = bitbuf;
+ }
+ *q++ = 0xf0;
+ bitmap += linesize;
+ buf_size -= q - line_begin;
+ }
+ len = q - *pq;
+ *pq = q;
+ return len;
+}
+
+static int dvb_encode_rle8(uint8_t **pq, int buf_size,
+ const uint8_t *bitmap, int linesize,
+ int w, int h)
+{
+ uint8_t *q, *line_begin;
+ int x, y, len, x1, color;
+
+ q = *pq;
+
+ for (y = 0; y < h; y++) {
+ // Worst case line is 12 bits per value, + 3 bytes overhead
+ if (buf_size * 8 < w * 12 + 24)
+ return AVERROR_BUFFER_TOO_SMALL;
+ line_begin = q;
+ *q++ = 0x12;
+
+ x = 0;
+ while (x < w) {
+ x1 = x;
+ color = bitmap[x1++];
+ while (x1 < w && bitmap[x1] == color)
+ x1++;
+ len = x1 - x;
+ if (len == 1 && color) {
+ // 00000001 to 11111111 1 pixel in colour x
+ *q++ = color;
+ } else {
+ if (color == 0x00) {
+ // 00000000 0LLLLLLL L pixels (1-127) in colour 0 (L > 0)
+ len = FFMIN(len, 127);
+ *q++ = 0x00;
+ *q++ = len;
+ } else if (len > 2) {
+ // 00000000 1LLLLLLL CCCCCCCC L pixels (3-127) in colour C (L > 2)
+ len = FFMIN(len, 127);
+ *q++ = 0x00;
+ *q++ = 0x80+len;
+ *q++ = color;
+ }
+ else if (len == 2) {
+ *q++ = color;
+ *q++ = color;
+ } else {
+ *q++ = color;
+ len = 1;
+ }
+ }
+ x += len;
+ }
+ /* end of line */
+ // 00000000 end of 8-bit/pixel_code_string
+ *q++ = 0x00;
+ *q++ = 0xf0;
+ bitmap += linesize;
+ buf_size -= q - line_begin;
+ }
+ len = q - *pq;
+ *pq = q;
+ return len;
+}
+
+static int dvbsub_encode(AVCodecContext *avctx, uint8_t *outbuf, int buf_size,
+ const AVSubtitle *h)
+{
+ DVBSubtitleContext *s = avctx->priv_data;
+ uint8_t *q, *pseg_len;
+ int page_id, region_id, clut_id, object_id, i, bpp_index, page_state;
+
+
+ q = outbuf;
+
+ page_id = 1;
+
+ if (h->num_rects && !h->rects)
+ return AVERROR(EINVAL);
+
+ if (avctx->width > 0 && avctx->height > 0) {
+ if (buf_size < 11)
+ return AVERROR_BUFFER_TOO_SMALL;
+ /* display definition segment */
+ *q++ = 0x0f; /* sync_byte */
+ *q++ = 0x14; /* segment_type */
+ bytestream_put_be16(&q, page_id);
+ pseg_len = q;
+ q += 2; /* segment length */
+ *q++ = 0x00; /* dds version number & display window flag */
+ bytestream_put_be16(&q, avctx->width - 1); /* display width */
+ bytestream_put_be16(&q, avctx->height - 1); /* display height */
+ bytestream_put_be16(&pseg_len, q - pseg_len - 2);
+ buf_size -= 11;
+ }
+
+ /* page composition segment */
+
+ if (buf_size < 8 + h->num_rects * 6)
+ return AVERROR_BUFFER_TOO_SMALL;
+ *q++ = 0x0f; /* sync_byte */
+ *q++ = 0x10; /* segment_type */
+ bytestream_put_be16(&q, page_id);
+ pseg_len = q;
+ q += 2; /* segment length */
+ *q++ = 30; /* page_timeout (seconds) */
+ page_state = 2; /* mode change */
+ /* page_version = 0 + page_state */
+ *q++ = (s->object_version << 4) | (page_state << 2) | 3;
+
+ for (region_id = 0; region_id < h->num_rects; region_id++) {
+ *q++ = region_id;
+ *q++ = 0xff; /* reserved */
+ bytestream_put_be16(&q, h->rects[region_id]->x); /* left pos */
+ bytestream_put_be16(&q, h->rects[region_id]->y); /* top pos */
+ }
+
+ bytestream_put_be16(&pseg_len, q - pseg_len - 2);
+ buf_size -= 8 + h->num_rects * 6;
+
+ if (h->num_rects) {
+ for (clut_id = 0; clut_id < h->num_rects; clut_id++) {
+ if (buf_size < 6 + h->rects[clut_id]->nb_colors * 6)
+ return AVERROR_BUFFER_TOO_SMALL;
+
+ /* CLUT segment */
+
+ if (h->rects[clut_id]->nb_colors <= 4) {
+ /* 2 bpp, some decoders do not support it correctly */
+ bpp_index = 0;
+ } else if (h->rects[clut_id]->nb_colors <= 16) {
+ /* 4 bpp, standard encoding */
+ bpp_index = 1;
+ } else if (h->rects[clut_id]->nb_colors <= 256) {
+ /* 8 bpp, standard encoding */
+ bpp_index = 2;
+ } else {
+ return AVERROR(EINVAL);
+ }
+
+
+ /* CLUT segment */
+ *q++ = 0x0f; /* sync byte */
+ *q++ = 0x12; /* CLUT definition segment */
+ bytestream_put_be16(&q, page_id);
+ pseg_len = q;
+ q += 2; /* segment length */
+ *q++ = clut_id;
+ *q++ = (0 << 4) | 0xf; /* version = 0 */
+
+ for(i = 0; i < h->rects[clut_id]->nb_colors; i++) {
+ *q++ = i; /* clut_entry_id */
+ *q++ = (1 << (7 - bpp_index)) | (0xf << 1) | 1; /* 2 bits/pixel full range */
+ {
+ int a, r, g, b;
+ uint32_t x= ((uint32_t*)h->rects[clut_id]->data[1])[i];
+ a = (x >> 24) & 0xff;
+ r = (x >> 16) & 0xff;
+ g = (x >> 8) & 0xff;
+ b = (x >> 0) & 0xff;
+
+ *q++ = RGB_TO_Y_CCIR(r, g, b);
+ *q++ = RGB_TO_V_CCIR(r, g, b, 0);
+ *q++ = RGB_TO_U_CCIR(r, g, b, 0);
+ *q++ = 255 - a;
+ }
+ }
+
+ bytestream_put_be16(&pseg_len, q - pseg_len - 2);
+ buf_size -= 6 + h->rects[clut_id]->nb_colors * 6;
+ }
+ }
+
+ if (buf_size < h->num_rects * 22)
+ return AVERROR_BUFFER_TOO_SMALL;
+ for (region_id = 0; region_id < h->num_rects; region_id++) {
+
+ /* region composition segment */
+
+ if (h->rects[region_id]->nb_colors <= 4) {
+ /* 2 bpp, some decoders do not support it correctly */
+ bpp_index = 0;
+ } else if (h->rects[region_id]->nb_colors <= 16) {
+ /* 4 bpp, standard encoding */
+ bpp_index = 1;
+ } else if (h->rects[region_id]->nb_colors <= 256) {
+ /* 8 bpp, standard encoding */
+ bpp_index = 2;
+ } else {
+ return AVERROR(EINVAL);
+ }
+
+ *q++ = 0x0f; /* sync_byte */
+ *q++ = 0x11; /* segment_type */
+ bytestream_put_be16(&q, page_id);
+ pseg_len = q;
+ q += 2; /* segment length */
+ *q++ = region_id;
+ *q++ = (s->object_version << 4) | (0 << 3) | 0x07; /* version , no fill */
+ bytestream_put_be16(&q, h->rects[region_id]->w); /* region width */
+ bytestream_put_be16(&q, h->rects[region_id]->h); /* region height */
+ *q++ = ((1 + bpp_index) << 5) | ((1 + bpp_index) << 2) | 0x03;
+ *q++ = region_id; /* clut_id == region_id */
+ *q++ = 0; /* 8 bit fill colors */
+ *q++ = 0x03; /* 4 bit and 2 bit fill colors */
+
+ bytestream_put_be16(&q, region_id); /* object_id == region_id */
+ *q++ = (0 << 6) | (0 << 4);
+ *q++ = 0;
+ *q++ = 0xf0;
+ *q++ = 0;
+
+ bytestream_put_be16(&pseg_len, q - pseg_len - 2);
+ }
+ buf_size -= h->num_rects * 22;
+
+ if (h->num_rects) {
+
+ for (object_id = 0; object_id < h->num_rects; object_id++) {
+ int (*dvb_encode_rle)(uint8_t **pq, int buf_size,
+ const uint8_t *bitmap, int linesize,
+ int w, int h);
+
+ if (buf_size < 13)
+ return AVERROR_BUFFER_TOO_SMALL;
+
+ /* bpp_index maths */
+ if (h->rects[object_id]->nb_colors <= 4) {
+ /* 2 bpp, some decoders do not support it correctly */
+ dvb_encode_rle = dvb_encode_rle2;
+ } else if (h->rects[object_id]->nb_colors <= 16) {
+ /* 4 bpp, standard encoding */
+ dvb_encode_rle = dvb_encode_rle4;
+ } else if (h->rects[object_id]->nb_colors <= 256) {
+ /* 8 bpp, standard encoding */
+ dvb_encode_rle = dvb_encode_rle8;
+ } else {
+ return AVERROR(EINVAL);
+ }
+
+ /* Object Data segment */
+ *q++ = 0x0f; /* sync byte */
+ *q++ = 0x13;
+ bytestream_put_be16(&q, page_id);
+ pseg_len = q;
+ q += 2; /* segment length */
+
+ bytestream_put_be16(&q, object_id);
+ *q++ = (s->object_version << 4) | (0 << 2) | (0 << 1) | 1; /* version = 0,
+ onject_coding_method,
+ non_modifying_color_flag */
+ {
+ uint8_t *ptop_field_len, *pbottom_field_len, *top_ptr, *bottom_ptr;
+ int ret;
+
+ ptop_field_len = q;
+ q += 2;
+ pbottom_field_len = q;
+ q += 2;
+ buf_size -= 13;
+
+ top_ptr = q;
+ ret = dvb_encode_rle(&q, buf_size,
+ h->rects[object_id]->data[0],
+ h->rects[object_id]->w * 2,
+ h->rects[object_id]->w,
+ h->rects[object_id]->h >> 1);
+ if (ret < 0)
+ return ret;
+ buf_size -= ret;
+ bottom_ptr = q;
+ ret = dvb_encode_rle(&q, buf_size,
+ h->rects[object_id]->data[0] + h->rects[object_id]->w,
+ h->rects[object_id]->w * 2,
+ h->rects[object_id]->w,
+ h->rects[object_id]->h >> 1);
+ if (ret < 0)
+ return ret;
+ buf_size -= ret;
+
+ bytestream_put_be16(&ptop_field_len, bottom_ptr - top_ptr);
+ bytestream_put_be16(&pbottom_field_len, q - bottom_ptr);
+ }
+
+ bytestream_put_be16(&pseg_len, q - pseg_len - 2);
+ }
+ }
+
+ /* end of display set segment */
+
+ if (buf_size < 6)
+ return AVERROR_BUFFER_TOO_SMALL;
+ *q++ = 0x0f; /* sync_byte */
+ *q++ = 0x80; /* segment_type */
+ bytestream_put_be16(&q, page_id);
+ pseg_len = q;
+ q += 2; /* segment length */
+
+ bytestream_put_be16(&pseg_len, q - pseg_len - 2);
+ buf_size -= 6;
+
+ s->object_version = (s->object_version + 1) & 0xf;
+ return q - outbuf;
+}
+
+AVCodec ff_dvbsub_encoder = {
+ .name = "dvbsub",
+ .long_name = NULL_IF_CONFIG_SMALL("DVB subtitles"),
+ .type = AVMEDIA_TYPE_SUBTITLE,
+ .id = AV_CODEC_ID_DVB_SUBTITLE,
+ .priv_data_size = sizeof(DVBSubtitleContext),
+ .encode_sub = dvbsub_encode,
+};
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-16 15:42:34 +0000