0,0 → 1,395 |
/* |
* 3GPP TS 26.245 Timed Text encoder |
* Copyright (c) 2012 Philip Langdale <philipl@overt.org> |
* |
* 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 <stdarg.h> |
#include "avcodec.h" |
#include "libavutil/avassert.h" |
#include "libavutil/avstring.h" |
#include "libavutil/intreadwrite.h" |
#include "libavutil/mem.h" |
#include "libavutil/common.h" |
#include "ass_split.h" |
#include "ass.h" |
|
#define STYLE_FLAG_BOLD (1<<0) |
#define STYLE_FLAG_ITALIC (1<<1) |
#define STYLE_FLAG_UNDERLINE (1<<2) |
#define STYLE_RECORD_SIZE 12 |
#define SIZE_ADD 10 |
|
#define STYL_BOX (1<<0) |
#define HLIT_BOX (1<<1) |
#define HCLR_BOX (1<<2) |
|
#define av_bprint_append_any(buf, data, size) av_bprint_append_data(buf, ((const char*)data), size) |
|
typedef struct { |
uint16_t style_start; |
uint16_t style_end; |
uint8_t style_flag; |
} StyleBox; |
|
typedef struct { |
uint16_t start; |
uint16_t end; |
} HighlightBox; |
|
typedef struct { |
uint32_t color; |
} HilightcolorBox; |
|
typedef struct { |
ASSSplitContext *ass_ctx; |
AVBPrint buffer; |
StyleBox **style_attributes; |
StyleBox *style_attributes_temp; |
HighlightBox hlit; |
HilightcolorBox hclr; |
int count; |
uint8_t box_flags; |
uint16_t style_entries; |
uint16_t style_fontID; |
uint8_t style_fontsize; |
uint32_t style_color; |
uint16_t text_pos; |
} MovTextContext; |
|
typedef struct { |
uint32_t type; |
void (*encode)(MovTextContext *s, uint32_t tsmb_type); |
} Box; |
|
static void mov_text_cleanup(MovTextContext *s) |
{ |
int j; |
if (s->box_flags & STYL_BOX) { |
for (j = 0; j < s->count; j++) { |
av_freep(&s->style_attributes[j]); |
} |
av_freep(&s->style_attributes); |
} |
} |
|
static void encode_styl(MovTextContext *s, uint32_t tsmb_type) |
{ |
int j; |
uint32_t tsmb_size; |
if (s->box_flags & STYL_BOX) { |
tsmb_size = s->count * STYLE_RECORD_SIZE + SIZE_ADD; |
tsmb_size = AV_RB32(&tsmb_size); |
s->style_entries = AV_RB16(&s->count); |
s->style_fontID = 0x00 | 0x01<<8; |
s->style_fontsize = 0x12; |
s->style_color = MKTAG(0xFF, 0xFF, 0xFF, 0xFF); |
/*The above three attributes are hard coded for now |
but will come from ASS style in the future*/ |
av_bprint_append_any(&s->buffer, &tsmb_size, 4); |
av_bprint_append_any(&s->buffer, &tsmb_type, 4); |
av_bprint_append_any(&s->buffer, &s->style_entries, 2); |
for (j = 0; j < s->count; j++) { |
av_bprint_append_any(&s->buffer, &s->style_attributes[j]->style_start, 2); |
av_bprint_append_any(&s->buffer, &s->style_attributes[j]->style_end, 2); |
av_bprint_append_any(&s->buffer, &s->style_fontID, 2); |
av_bprint_append_any(&s->buffer, &s->style_attributes[j]->style_flag, 1); |
av_bprint_append_any(&s->buffer, &s->style_fontsize, 1); |
av_bprint_append_any(&s->buffer, &s->style_color, 4); |
} |
mov_text_cleanup(s); |
} |
} |
|
static void encode_hlit(MovTextContext *s, uint32_t tsmb_type) |
{ |
uint32_t tsmb_size; |
if (s->box_flags & HLIT_BOX) { |
tsmb_size = 12; |
tsmb_size = AV_RB32(&tsmb_size); |
av_bprint_append_any(&s->buffer, &tsmb_size, 4); |
av_bprint_append_any(&s->buffer, &tsmb_type, 4); |
av_bprint_append_any(&s->buffer, &s->hlit.start, 2); |
av_bprint_append_any(&s->buffer, &s->hlit.end, 2); |
} |
} |
|
static void encode_hclr(MovTextContext *s, uint32_t tsmb_type) |
{ |
uint32_t tsmb_size; |
if (s->box_flags & HCLR_BOX) { |
tsmb_size = 12; |
tsmb_size = AV_RB32(&tsmb_size); |
av_bprint_append_any(&s->buffer, &tsmb_size, 4); |
av_bprint_append_any(&s->buffer, &tsmb_type, 4); |
av_bprint_append_any(&s->buffer, &s->hclr.color, 4); |
} |
} |
|
static const Box box_types[] = { |
{ MKTAG('s','t','y','l'), encode_styl }, |
{ MKTAG('h','l','i','t'), encode_hlit }, |
{ MKTAG('h','c','l','r'), encode_hclr }, |
}; |
|
const static size_t box_count = FF_ARRAY_ELEMS(box_types); |
|
static av_cold int mov_text_encode_init(AVCodecContext *avctx) |
{ |
/* |
* For now, we'll use a fixed default style. When we add styling |
* support, this will be generated from the ASS style. |
*/ |
static const uint8_t text_sample_entry[] = { |
0x00, 0x00, 0x00, 0x00, // uint32_t displayFlags |
0x01, // int8_t horizontal-justification |
0xFF, // int8_t vertical-justification |
0x00, 0x00, 0x00, 0x00, // uint8_t background-color-rgba[4] |
// BoxRecord { |
0x00, 0x00, // int16_t top |
0x00, 0x00, // int16_t left |
0x00, 0x00, // int16_t bottom |
0x00, 0x00, // int16_t right |
// }; |
// StyleRecord { |
0x00, 0x00, // uint16_t startChar |
0x00, 0x00, // uint16_t endChar |
0x00, 0x01, // uint16_t font-ID |
0x00, // uint8_t face-style-flags |
0x12, // uint8_t font-size |
0xFF, 0xFF, 0xFF, 0xFF, // uint8_t text-color-rgba[4] |
// }; |
// FontTableBox { |
0x00, 0x00, 0x00, 0x12, // uint32_t size |
'f', 't', 'a', 'b', // uint8_t name[4] |
0x00, 0x01, // uint16_t entry-count |
// FontRecord { |
0x00, 0x01, // uint16_t font-ID |
0x05, // uint8_t font-name-length |
'S', 'e', 'r', 'i', 'f',// uint8_t font[font-name-length] |
// }; |
// }; |
}; |
|
MovTextContext *s = avctx->priv_data; |
|
avctx->extradata_size = sizeof text_sample_entry; |
avctx->extradata = av_mallocz(avctx->extradata_size + AV_INPUT_BUFFER_PADDING_SIZE); |
if (!avctx->extradata) |
return AVERROR(ENOMEM); |
|
av_bprint_init(&s->buffer, 0, AV_BPRINT_SIZE_UNLIMITED); |
|
memcpy(avctx->extradata, text_sample_entry, avctx->extradata_size); |
|
s->ass_ctx = ff_ass_split(avctx->subtitle_header); |
return s->ass_ctx ? 0 : AVERROR_INVALIDDATA; |
} |
|
static void mov_text_style_cb(void *priv, const char style, int close) |
{ |
MovTextContext *s = priv; |
if (!close) { |
if (!(s->box_flags & STYL_BOX)) { //first style entry |
|
s->style_attributes_temp = av_malloc(sizeof(*s->style_attributes_temp)); |
|
if (!s->style_attributes_temp) { |
av_bprint_clear(&s->buffer); |
s->box_flags &= ~STYL_BOX; |
return; |
} |
|
s->style_attributes_temp->style_flag = 0; |
s->style_attributes_temp->style_start = AV_RB16(&s->text_pos); |
} else { |
if (s->style_attributes_temp->style_flag) { //break the style record here and start a new one |
s->style_attributes_temp->style_end = AV_RB16(&s->text_pos); |
av_dynarray_add(&s->style_attributes, &s->count, s->style_attributes_temp); |
s->style_attributes_temp = av_malloc(sizeof(*s->style_attributes_temp)); |
if (!s->style_attributes_temp) { |
mov_text_cleanup(s); |
av_bprint_clear(&s->buffer); |
s->box_flags &= ~STYL_BOX; |
return; |
} |
|
s->style_attributes_temp->style_flag = s->style_attributes[s->count - 1]->style_flag; |
s->style_attributes_temp->style_start = AV_RB16(&s->text_pos); |
} else { |
s->style_attributes_temp->style_flag = 0; |
s->style_attributes_temp->style_start = AV_RB16(&s->text_pos); |
} |
} |
switch (style){ |
case 'b': |
s->style_attributes_temp->style_flag |= STYLE_FLAG_BOLD; |
break; |
case 'i': |
s->style_attributes_temp->style_flag |= STYLE_FLAG_ITALIC; |
break; |
case 'u': |
s->style_attributes_temp->style_flag |= STYLE_FLAG_UNDERLINE; |
break; |
} |
} else { |
s->style_attributes_temp->style_end = AV_RB16(&s->text_pos); |
av_dynarray_add(&s->style_attributes, &s->count, s->style_attributes_temp); |
|
s->style_attributes_temp = av_malloc(sizeof(*s->style_attributes_temp)); |
|
if (!s->style_attributes_temp) { |
mov_text_cleanup(s); |
av_bprint_clear(&s->buffer); |
s->box_flags &= ~STYL_BOX; |
return; |
} |
|
s->style_attributes_temp->style_flag = s->style_attributes[s->count - 1]->style_flag; |
switch (style){ |
case 'b': |
s->style_attributes_temp->style_flag &= ~STYLE_FLAG_BOLD; |
break; |
case 'i': |
s->style_attributes_temp->style_flag &= ~STYLE_FLAG_ITALIC; |
break; |
case 'u': |
s->style_attributes_temp->style_flag &= ~STYLE_FLAG_UNDERLINE; |
break; |
} |
if (s->style_attributes_temp->style_flag) { //start of new style record |
s->style_attributes_temp->style_start = AV_RB16(&s->text_pos); |
} |
} |
s->box_flags |= STYL_BOX; |
} |
|
static void mov_text_color_cb(void *priv, unsigned int color, unsigned int color_id) |
{ |
MovTextContext *s = priv; |
if (color_id == 2) { //secondary color changes |
if (s->box_flags & HLIT_BOX) { //close tag |
s->hlit.end = AV_RB16(&s->text_pos); |
} else { |
s->box_flags |= HCLR_BOX; |
s->box_flags |= HLIT_BOX; |
s->hlit.start = AV_RB16(&s->text_pos); |
s->hclr.color = color | (0xFF << 24); //set alpha value to FF |
} |
} |
/* If there are more than one secondary color changes in ASS, take start of |
first section and end of last section. Movtext allows only one |
highlight box per sample. |
*/ |
} |
|
static void mov_text_text_cb(void *priv, const char *text, int len) |
{ |
MovTextContext *s = priv; |
av_bprint_append_data(&s->buffer, text, len); |
s->text_pos += len; |
} |
|
static void mov_text_new_line_cb(void *priv, int forced) |
{ |
MovTextContext *s = priv; |
av_bprint_append_data(&s->buffer, "\n", 1); |
s->text_pos += 1; |
} |
|
static const ASSCodesCallbacks mov_text_callbacks = { |
.text = mov_text_text_cb, |
.new_line = mov_text_new_line_cb, |
.style = mov_text_style_cb, |
.color = mov_text_color_cb, |
}; |
|
static int mov_text_encode_frame(AVCodecContext *avctx, unsigned char *buf, |
int bufsize, const AVSubtitle *sub) |
{ |
MovTextContext *s = avctx->priv_data; |
ASSDialog *dialog; |
int i, num, length; |
size_t j; |
|
s->text_pos = 0; |
s->count = 0; |
s->box_flags = 0; |
s->style_entries = 0; |
for (i = 0; i < sub->num_rects; i++) { |
|
if (sub->rects[i]->type != SUBTITLE_ASS) { |
av_log(avctx, AV_LOG_ERROR, "Only SUBTITLE_ASS type supported.\n"); |
return AVERROR(ENOSYS); |
} |
|
dialog = ff_ass_split_dialog(s->ass_ctx, sub->rects[i]->ass, 0, &num); |
for (; dialog && num--; dialog++) { |
ff_ass_split_override_codes(&mov_text_callbacks, s, dialog->text); |
} |
|
for (j = 0; j < box_count; j++) { |
box_types[j].encode(s, box_types[j].type); |
} |
} |
|
AV_WB16(buf, s->text_pos); |
buf += 2; |
|
if (!av_bprint_is_complete(&s->buffer)) { |
length = AVERROR(ENOMEM); |
goto exit; |
} |
|
if (!s->buffer.len) { |
length = 0; |
goto exit; |
} |
|
if (s->buffer.len > bufsize - 3) { |
av_log(avctx, AV_LOG_ERROR, "Buffer too small for ASS event.\n"); |
length = AVERROR(EINVAL); |
goto exit; |
} |
|
memcpy(buf, s->buffer.str, s->buffer.len); |
length = s->buffer.len + 2; |
|
exit: |
av_bprint_clear(&s->buffer); |
return length; |
} |
|
static int mov_text_encode_close(AVCodecContext *avctx) |
{ |
MovTextContext *s = avctx->priv_data; |
ff_ass_split_free(s->ass_ctx); |
av_bprint_finalize(&s->buffer, NULL); |
return 0; |
} |
|
AVCodec ff_movtext_encoder = { |
.name = "mov_text", |
.long_name = NULL_IF_CONFIG_SMALL("3GPP Timed Text subtitle"), |
.type = AVMEDIA_TYPE_SUBTITLE, |
.id = AV_CODEC_ID_MOV_TEXT, |
.priv_data_size = sizeof(MovTextContext), |
.init = mov_text_encode_init, |
.encode_sub = mov_text_encode_frame, |
.close = mov_text_encode_close, |
}; |