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mpv/libass/ass_render.c

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// -*- c-basic-offset: 8; indent-tabs-mode: t -*-
// vim:ts=8:sw=8:noet:ai:
/*
Copyright (C) 2006 Evgeniy Stepanov <eugeni.stepanov@gmail.com>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "config.h"
#include <assert.h>
#include <math.h>
#include <inttypes.h>
#include <ft2build.h>
#include FT_FREETYPE_H
#include FT_STROKER_H
#include FT_GLYPH_H
#include FT_SYNTHESIS_H
#include "mp_msg.h"
#include "ass.h"
#include "ass_bitmap.h"
#include "ass_cache.h"
#include "ass_utils.h"
#include "ass_fontconfig.h"
#include "ass_library.h"
#include "libvo/sub.h" // for utf8_get_char
#include "libavutil/common.h"
#define MAX_GLYPHS 1000
#define MAX_LINES 100
static int last_render_id = 0;
typedef struct ass_settings_s {
int frame_width;
int frame_height;
double font_size_coeff; // font size multiplier
double line_spacing; // additional line spacing (in frame pixels)
int top_margin; // height of top margin. Everything except toptitles is shifted down by top_margin.
int bottom_margin; // height of bottom margin. (frame_height - top_margin - bottom_margin) is original video height.
int left_margin;
int right_margin;
int use_margins; // 0 - place all subtitles inside original frame
// 1 - use margins for placing toptitles and subtitles
double aspect; // frame aspect ratio, d_width / d_height.
char* default_font;
char* default_family;
} ass_settings_t;
struct ass_renderer_s {
ass_library_t* library;
FT_Library ftlibrary;
fc_instance_t* fontconfig_priv;
ass_settings_t settings;
int render_id;
ass_synth_priv_t* synth_priv;
ass_image_t* images_root; // rendering result is stored here
};
int no_more_font_messages = 0; // don't print font warnings
typedef enum {EF_NONE = 0, EF_KARAOKE, EF_KARAOKE_KF, EF_KARAOKE_KO} effect_t;
// describes a glyph
// glyph_info_t and text_info_t are used for text centering and word-wrapping operations
typedef struct glyph_info_s {
unsigned symbol;
FT_Glyph glyph;
FT_Glyph outline_glyph;
bitmap_t* bm; // glyph bitmap
bitmap_t* bm_o; // outline bitmap
bitmap_t* bm_s; // shadow bitmap
FT_BBox bbox;
FT_Vector pos;
char linebreak; // the first (leading) glyph of some line ?
uint32_t c[4]; // colors
FT_Vector advance; // 26.6
effect_t effect_type;
int effect_timing; // time duration of current karaoke word
// after process_karaoke_effects: distance in pixels from the glyph origin.
// part of the glyph to the left of it is displayed in a different color.
int effect_skip_timing; // delay after the end of last karaoke word
int asc, desc; // font max ascender and descender
// int height;
int be; // blur edges
int shadow;
double frz; // z-axis rotation
glyph_hash_key_t hash_key;
} glyph_info_t;
typedef struct line_info_s {
int asc, desc;
} line_info_t;
typedef struct text_info_s {
glyph_info_t* glyphs;
int length;
line_info_t lines[MAX_LINES];
int n_lines;
int height;
} text_info_t;
// Renderer state.
// Values like current font face, color, screen position, clipping and so on are stored here.
typedef struct render_context_s {
ass_event_t* event;
ass_style_t* style;
FT_Face face;
char* font_path;
int font_size;
FT_Stroker stroker;
int alignment; // alignment overrides go here; if zero, style value will be used
double rotation;
enum { EVENT_NORMAL, // "normal" top-, sub- or mid- title
EVENT_POSITIONED, // happens after pos(,), margins are ignored
EVENT_HSCROLL, // "Banner" transition effect, text_width is unlimited
EVENT_VSCROLL // "Scroll up", "Scroll down" transition effects
} evt_type;
int pos_x, pos_y; // position
int org_x, org_y; // origin
double scale_x, scale_y;
int hspacing; // distance between letters, in pixels
double border; // outline width
uint32_t c[4]; // colors(Primary, Secondary, so on) in RGBA
int clip_x0, clip_y0, clip_x1, clip_y1;
char detect_collisions;
uint32_t fade; // alpha from \fad
char be; // blur edges
int shadow;
effect_t effect_type;
int effect_timing;
int effect_skip_timing;
enum { SCROLL_LR, // left-to-right
SCROLL_RL,
SCROLL_TB, // top-to-bottom
SCROLL_BT
} scroll_direction; // for EVENT_HSCROLL, EVENT_VSCROLL
int scroll_shift;
// face properties
char* family;
unsigned bold;
unsigned italic;
} render_context_t;
// frame-global data
typedef struct frame_context_s {
ass_renderer_t* ass_priv;
int width, height; // screen dimensions
int orig_height; // frame height ( = screen height - margins )
int orig_width; // frame width ( = screen width - margins )
ass_track_t* track;
long long time; // frame's timestamp, ms
double font_scale;
double font_scale_x; // x scale applied to all glyphs to preserve text aspect ratio
double border_scale;
} frame_context_t;
static ass_renderer_t* ass_renderer;
static ass_settings_t* global_settings;
static text_info_t text_info;
static render_context_t render_context;
static frame_context_t frame_context;
// a rendered event
typedef struct event_images_s {
ass_image_t* imgs;
int top, height;
int detect_collisions;
int shift_direction;
ass_event_t* event;
} event_images_t;
struct render_priv_s {
int top, height;
int render_id;
};
static void ass_lazy_track_init(void)
{
ass_track_t* track = frame_context.track;
if (track->PlayResX && track->PlayResY)
return;
if (!track->PlayResX && !track->PlayResY) {
mp_msg(MSGT_ASS, MSGL_WARN, "Neither PlayResX nor PlayResY defined. Assuming 384x288. \n");
track->PlayResX = 384;
track->PlayResY = 288;
} else {
double orig_aspect = (global_settings->aspect * frame_context.height * frame_context.orig_width) /
frame_context.orig_height / frame_context.width;
if (!track->PlayResY) {
track->PlayResY = track->PlayResX / orig_aspect + .5;
mp_msg(MSGT_ASS, MSGL_WARN, "PlayResY undefined, setting %d \n", track->PlayResY);
} else if (!track->PlayResX) {
track->PlayResX = track->PlayResY * orig_aspect + .5;
mp_msg(MSGT_ASS, MSGL_WARN, "PlayResX undefined, setting %d \n", track->PlayResX);
}
}
}
ass_renderer_t* ass_renderer_init(ass_library_t* library)
{
int error;
FT_Library ft;
ass_renderer_t* priv = 0;
memset(&render_context, 0, sizeof(render_context));
memset(&frame_context, 0, sizeof(frame_context));
memset(&text_info, 0, sizeof(text_info));
error = FT_Init_FreeType( &ft );
if ( error ) {
mp_msg(MSGT_ASS, MSGL_FATAL, "FT_Init_FreeType failed\n");
goto ass_init_exit;
}
priv = calloc(1, sizeof(ass_renderer_t));
if (!priv) {
FT_Done_FreeType(ft);
goto ass_init_exit;
}
priv->synth_priv = ass_synth_init();
priv->library = library;
priv->ftlibrary = ft;
// images_root and related stuff is zero-filled in calloc
ass_face_cache_init();
ass_glyph_cache_init();
text_info.glyphs = calloc(MAX_GLYPHS, sizeof(glyph_info_t));
ass_init_exit:
if (priv) mp_msg(MSGT_ASS, MSGL_INFO, "[ass] Init\n");
else mp_msg(MSGT_ASS, MSGL_ERR, "[ass] Init failed\n");
return priv;
}
void ass_renderer_done(ass_renderer_t* priv)
{
ass_face_cache_done();
ass_glyph_cache_done();
if (render_context.stroker) {
FT_Stroker_Done(render_context.stroker);
render_context.stroker = 0;
}
if (priv && priv->ftlibrary) FT_Done_FreeType(priv->ftlibrary);
if (priv && priv->fontconfig_priv) fontconfig_done(priv->fontconfig_priv);
if (priv && priv->synth_priv) ass_synth_done(priv->synth_priv);
if (priv) free(priv);
if (text_info.glyphs) free(text_info.glyphs);
}
/**
* \brief Create a new ass_image_t
* Parameters are the same as ass_image_t fields.
*/
static ass_image_t* my_draw_bitmap(unsigned char* bitmap, int bitmap_w, int bitmap_h, int stride, int dst_x, int dst_y, uint32_t color)
{
ass_image_t* img = calloc(1, sizeof(ass_image_t));
img->w = bitmap_w;
img->h = bitmap_h;
img->stride = stride;
img->bitmap = bitmap;
img->color = color;
img->dst_x = dst_x;
img->dst_y = dst_y;
return img;
}
/**
* \brief convert bitmap glyph into ass_image_t struct(s)
* \param bit freetype bitmap glyph, FT_PIXEL_MODE_GRAY
* \param dst_x bitmap x coordinate in video frame
* \param dst_y bitmap y coordinate in video frame
* \param color first color, RGBA
* \param color2 second color, RGBA
* \param brk x coordinate relative to glyph origin, color is used to the left of brk, color2 - to the right
* \param tail pointer to the last image's next field, head of the generated list should be stored here
* \return pointer to the new list tail
* Performs clipping. Uses my_draw_bitmap for actual bitmap convertion.
*/
static ass_image_t** render_glyph(bitmap_t* bm, int dst_x, int dst_y, uint32_t color, uint32_t color2, int brk, ass_image_t** tail)
{
// brk is relative to dst_x
// color = color left of brk
// color2 = color right of brk
int b_x0, b_y0, b_x1, b_y1; // visible part of the bitmap
int clip_x0, clip_y0, clip_x1, clip_y1;
int tmp;
ass_image_t* img;
dst_x += bm->left;
dst_y += bm->top;
brk -= bm->left;
// clipping
clip_x0 = render_context.clip_x0;
clip_y0 = render_context.clip_y0;
clip_x1 = render_context.clip_x1;
clip_y1 = render_context.clip_y1;
b_x0 = 0;
b_y0 = 0;
b_x1 = bm->w;
b_y1 = bm->h;
tmp = dst_x - clip_x0;
if (tmp < 0) {
mp_msg(MSGT_ASS, MSGL_DBG2, "clip left\n");
b_x0 = - tmp;
}
tmp = dst_y - clip_y0;
if (tmp < 0) {
mp_msg(MSGT_ASS, MSGL_DBG2, "clip top\n");
b_y0 = - tmp;
}
tmp = clip_x1 - dst_x - bm->w;
if (tmp < 0) {
mp_msg(MSGT_ASS, MSGL_DBG2, "clip right\n");
b_x1 = bm->w + tmp;
}
tmp = clip_y1 - dst_y - bm->h;
if (tmp < 0) {
mp_msg(MSGT_ASS, MSGL_DBG2, "clip bottom\n");
b_y1 = bm->h + tmp;
}
if ((b_y0 >= b_y1) || (b_x0 >= b_x1))
return tail;
if (brk > b_x0) { // draw left part
if (brk > b_x1) brk = b_x1;
img = my_draw_bitmap(bm->buffer + bm->w * b_y0 + b_x0,
brk - b_x0, b_y1 - b_y0, bm->w,
dst_x + b_x0, dst_y + b_y0, color);
*tail = img;
tail = &img->next;
}
if (brk < b_x1) { // draw right part
if (brk < b_x0) brk = b_x0;
img = my_draw_bitmap(bm->buffer + bm->w * b_y0 + brk,
b_x1 - brk, b_y1 - b_y0, bm->w,
dst_x + brk, dst_y + b_y0, color2);
*tail = img;
tail = &img->next;
}
return tail;
}
/**
* \brief Render text_info_t struct into ass_images_t list
* Rasterize glyphs and put them in glyph cache.
*/
static ass_image_t* render_text(text_info_t* text_info, int dst_x, int dst_y)
{
int pen_x, pen_y;
int i, error;
bitmap_t* bm;
glyph_hash_val_t hash_val;
ass_image_t* head;
ass_image_t** tail = &head;
for (i = 0; i < text_info->length; ++i) {
if (text_info->glyphs[i].glyph) {
if ((text_info->glyphs[i].symbol == '\n') || (text_info->glyphs[i].symbol == 0))
continue;
error = glyph_to_bitmap(ass_renderer->synth_priv,
text_info->glyphs[i].glyph, text_info->glyphs[i].outline_glyph,
&text_info->glyphs[i].bm, &text_info->glyphs[i].bm_o,
&text_info->glyphs[i].bm_s, text_info->glyphs[i].be);
if (error)
text_info->glyphs[i].symbol = 0;
FT_Done_Glyph(text_info->glyphs[i].glyph);
if (text_info->glyphs[i].outline_glyph)
FT_Done_Glyph(text_info->glyphs[i].outline_glyph);
// cache
hash_val.bbox_scaled = text_info->glyphs[i].bbox;
hash_val.bm_o = text_info->glyphs[i].bm_o;
hash_val.bm = text_info->glyphs[i].bm;
hash_val.bm_s = text_info->glyphs[i].bm_s;
hash_val.advance.x = text_info->glyphs[i].advance.x;
hash_val.advance.y = text_info->glyphs[i].advance.y;
cache_add_glyph(&(text_info->glyphs[i].hash_key), &hash_val);
}
}
for (i = 0; i < text_info->length; ++i) {
glyph_info_t* info = text_info->glyphs + i;
if ((info->symbol == 0) || (info->symbol == '\n') || !info->bm_s || (info->shadow == 0))
continue;
pen_x = dst_x + info->pos.x + info->shadow;
pen_y = dst_y + info->pos.y + info->shadow;
bm = info->bm_s;
tail = render_glyph(bm, pen_x, pen_y, info->c[3], 0, 1000000, tail);
}
for (i = 0; i < text_info->length; ++i) {
glyph_info_t* info = text_info->glyphs + i;
if ((info->symbol == 0) || (info->symbol == '\n') || !info->bm_o)
continue;
pen_x = dst_x + info->pos.x;
pen_y = dst_y + info->pos.y;
bm = info->bm_o;
if ((info->effect_type == EF_KARAOKE_KO) && (info->effect_timing <= info->bbox.xMax)) {
// do nothing
} else
tail = render_glyph(bm, pen_x, pen_y, info->c[2], 0, 1000000, tail);
}
for (i = 0; i < text_info->length; ++i) {
glyph_info_t* info = text_info->glyphs + i;
if ((info->symbol == 0) || (info->symbol == '\n') || !info->bm)
continue;
pen_x = dst_x + info->pos.x;
pen_y = dst_y + info->pos.y;
bm = info->bm;
if ((info->effect_type == EF_KARAOKE) || (info->effect_type == EF_KARAOKE_KO)) {
if (info->effect_timing > info->bbox.xMax)
tail = render_glyph(bm, pen_x, pen_y, info->c[0], 0, 1000000, tail);
else
tail = render_glyph(bm, pen_x, pen_y, info->c[1], 0, 1000000, tail);
} else if (info->effect_type == EF_KARAOKE_KF) {
tail = render_glyph(bm, pen_x, pen_y, info->c[0], info->c[1], info->effect_timing, tail);
} else
tail = render_glyph(bm, pen_x, pen_y, info->c[0], 0, 1000000, tail);
}
*tail = 0;
return head;
}
/**
* \brief Mapping between script and screen coordinates
*/
static int x2scr(int x) {
return x*frame_context.orig_width / frame_context.track->PlayResX + global_settings->left_margin;
}
/**
* \brief Mapping between script and screen coordinates
*/
static int y2scr(int y) {
return y * frame_context.orig_height / frame_context.track->PlayResY + global_settings->top_margin;
}
// the same for toptitles
static int y2scr_top(int y) {
if (global_settings->use_margins)
return y * frame_context.orig_height / frame_context.track->PlayResY;
else
return y * frame_context.orig_height / frame_context.track->PlayResY + global_settings->top_margin;
}
// the same for subtitles
static int y2scr_sub(int y) {
if (global_settings->use_margins)
return y * frame_context.orig_height / frame_context.track->PlayResY +
global_settings->top_margin + global_settings->bottom_margin;
else
return y * frame_context.orig_height / frame_context.track->PlayResY + global_settings->top_margin;
}
static void vmirror_bbox(FT_BBox* orig, FT_BBox* pbbox) {
pbbox->xMin = orig->xMin;
pbbox->xMax = orig->xMax;
pbbox->yMin = - orig->yMax;
pbbox->yMax = - orig->yMin;
}
static void compute_string_bbox( text_info_t* info, FT_BBox *abbox ) {
FT_BBox bbox;
int n;
/* initialize string bbox to "empty" values */
bbox.xMin = bbox.yMin = 32000;
bbox.xMax = bbox.yMax = -32000;
/* for each glyph image, compute its bounding box, */
/* translate it, and grow the string bbox */
for ( n = 0; n < info->length; n++ ) {
FT_BBox glyph_bbox;
vmirror_bbox( &(info->glyphs[n].bbox), &glyph_bbox );
glyph_bbox.xMin += info->glyphs[n].pos.x;
glyph_bbox.xMax += info->glyphs[n].pos.x;
glyph_bbox.yMin += info->glyphs[n].pos.y;
glyph_bbox.yMax += info->glyphs[n].pos.y;
if ( glyph_bbox.xMin < bbox.xMin ) bbox.xMin = glyph_bbox.xMin;
if ( glyph_bbox.yMin < bbox.yMin ) bbox.yMin = glyph_bbox.yMin;
if ( glyph_bbox.xMax > bbox.xMax ) bbox.xMax = glyph_bbox.xMax;
if ( glyph_bbox.yMax > bbox.yMax ) bbox.yMax = glyph_bbox.yMax;
}
/* check that we really grew the string bbox */
if ( bbox.xMin > bbox.xMax ) {
bbox.xMin = 0;
bbox.yMin = 0;
bbox.xMax = 0;
bbox.yMax = 0;
}
/* return string bbox */
*abbox = bbox;
}
/**
* \brief Check if starting part of (*p) matches sample. If true, shift p to the first symbol after the matching part.
*/
static inline int mystrcmp(char** p, const char* sample) {
int len = strlen(sample);
if (strncmp(*p, sample, len) == 0) {
(*p) += len;
return 1;
} else
return 0;
}
double ass_internal_font_size_coeff = 0.8;
static void change_font_size(int sz)
{
double size = sz * frame_context.font_scale;
if (size < 1)
size = 1;
else if (size > frame_context.height * 2)
size = frame_context.height * 2;
FT_Set_Pixel_Sizes(render_context.face, 0, size);
render_context.font_size = sz;
}
/**
* \brief Change current font, using setting from render_context.
*/
static void update_font(void)
{
int error;
unsigned val;
ass_renderer_t* priv = frame_context.ass_priv;
face_desc_t desc;
desc.family = strdup(render_context.family);
val = render_context.bold;
// 0 = normal, 1 = bold, >1 = exact weight
if (val == 0) val = 80; // normal
else if (val == 1) val = 200; // bold
desc.bold = val;
val = render_context.italic;
if (val == 0) val = 0; // normal
else if (val == 1) val = 110; //italic
desc.italic = val;
error = ass_new_face(priv->ftlibrary, priv->fontconfig_priv, &desc, &(render_context.face));
if (error) {
render_context.face = 0;
}
if (render_context.face)
change_font_size(render_context.font_size);
}
/**
* \brief Change border width
* negative value resets border to style value
*/
static void change_border(double border)
{
int b;
if (!render_context.face) return;
if (border < 0) {
if (render_context.style->BorderStyle == 1) {
if (render_context.style->Outline == 0 && render_context.style->Shadow > 0)
border = 1.;
else
border = render_context.style->Outline;
} else
border = 1.;
}
render_context.border = border;
b = 64 * border * frame_context.border_scale;
if (b > 0) {
if (!render_context.stroker) {
int error;
#if (FREETYPE_MAJOR > 2) || ((FREETYPE_MAJOR == 2) && (FREETYPE_MINOR > 1))
error = FT_Stroker_New( ass_renderer->ftlibrary, &render_context.stroker );
#else // < 2.2
error = FT_Stroker_New( render_context.face->memory, &render_context.stroker );
#endif
if (error) {
mp_msg(MSGT_ASS, MSGL_V, "failed to get stroker\n");
render_context.stroker = 0;
}
}
if (render_context.stroker)
FT_Stroker_Set( render_context.stroker, b,
FT_STROKER_LINECAP_ROUND,
FT_STROKER_LINEJOIN_ROUND,
0 );
} else {
FT_Stroker_Done(render_context.stroker);
render_context.stroker = 0;
}
}
#define _r(c) ((c)>>24)
#define _g(c) (((c)>>16)&0xFF)
#define _b(c) (((c)>>8)&0xFF)
#define _a(c) ((c)&0xFF)
/**
* \brief Calculate a weighted average of two colors
* calculates c1*(1-a) + c2*a, but separately for each component except alpha
*/
static void change_color(uint32_t* var, uint32_t new, double pwr)
{
(*var)= ((uint32_t)(_r(*var) * (1 - pwr) + _r(new) * pwr) << 24) +
((uint32_t)(_g(*var) * (1 - pwr) + _g(new) * pwr) << 16) +
((uint32_t)(_b(*var) * (1 - pwr) + _b(new) * pwr) << 8) +
_a(*var);
}
// like change_color, but for alpha component only
static void change_alpha(uint32_t* var, uint32_t new, double pwr)
{
*var = (_r(*var) << 24) + (_g(*var) << 16) + (_b(*var) << 8) + (_a(*var) * (1 - pwr) + _a(new) * pwr);
}
/**
* \brief Multiply two alpha values
* \param a first value
* \param b second value
* \return result of multiplication
* Parameters and result are limited by 0xFF.
*/
static uint32_t mult_alpha(uint32_t a, uint32_t b)
{
return 0xFF - (0xFF - a) * (0xFF - b) / 0xFF;
}
/**
* \brief Calculate alpha value by piecewise linear function
* Used for \fad, \fade implementation.
*/
static unsigned interpolate_alpha(long long now,
long long t1, long long t2, long long t3, long long t4,
unsigned a1, unsigned a2, unsigned a3)
{
unsigned a;
double cf;
if (now <= t1) {
a = a1;
} else if (now >= t4) {
a = a3;
} else if (now < t2) { // and > t1
cf = ((double)(now - t1)) / (t2 - t1);
a = a1 * (1 - cf) + a2 * cf;
} else if (now > t3) {
cf = ((double)(now - t3)) / (t4 - t3);
a = a2 * (1 - cf) + a3 * cf;
} else { // t2 <= now <= t3
a = a2;
}
return a;
}
static void reset_render_context();
/**
* \brief Parse style override tag.
* \param p string to parse
* \param pwr multiplier for some tag effects (comes from \t tags)
*/
static char* parse_tag(char* p, double pwr) {
#define skip_all(x) if (*p == (x)) ++p; else { \
while ((*p != (x)) && (*p != '}') && (*p != 0)) {++p;} }
#define skip(x) if (*p == (x)) ++p; else { return p; }
skip_all('\\');
if ((*p == '}') || (*p == 0))
return p;
if (mystrcmp(&p, "fsc")) {
char tp = *p++;
double val;
if (tp == 'x') {
if (mystrtod(&p, &val)) {
val /= 100;
render_context.scale_x = (val - 1.) * pwr + 1.;
} else
render_context.scale_x = render_context.style->ScaleX;
} else if (tp == 'y') {
if (mystrtod(&p, &val)) {
val /= 100;
render_context.scale_y = (val - 1.) * pwr + 1.;
} else
render_context.scale_y = render_context.style->ScaleY;
}
} else if (mystrcmp(&p, "fsp")) {
int val;
if (mystrtoi(&p, 10, &val))
render_context.hspacing = val * pwr;
else
render_context.hspacing = 0;
} else if (mystrcmp(&p, "fs")) {
int val;
if (mystrtoi(&p, 10, &val))
val = render_context.font_size * ( 1 - pwr ) + val * pwr;
else
val = render_context.style->FontSize;
if (render_context.face)
change_font_size(val);
} else if (mystrcmp(&p, "bord")) {
double val;
if (mystrtod(&p, &val))
val = render_context.border * ( 1 - pwr ) + val * pwr;
else
val = -1.; // reset to default
change_border(val);
} else if (mystrcmp(&p, "move")) {
int x1, x2, y1, y2;
long long t1, t2, delta_t, t;
int x, y;
double k;
skip('(');
x1 = strtol(p, &p, 10);
skip(',');
y1 = strtol(p, &p, 10);
skip(',');
x2 = strtol(p, &p, 10);
skip(',');
y2 = strtol(p, &p, 10);
if (*p == ',') {
skip(',');
t1 = strtoll(p, &p, 10);
skip(',');
t2 = strtoll(p, &p, 10);
mp_msg(MSGT_ASS, MSGL_DBG2, "movement6: (%d, %d) -> (%d, %d), (%" PRId64 " .. %" PRId64 ")\n",
x1, y1, x2, y2, (int64_t)t1, (int64_t)t2);
} else {
t1 = 0;
t2 = render_context.event->Duration;
mp_msg(MSGT_ASS, MSGL_DBG2, "movement: (%d, %d) -> (%d, %d)\n", x1, y1, x2, y2);
}
skip(')');
delta_t = t2 - t1;
t = frame_context.time - render_context.event->Start;
if (t < t1)
k = 0.;
else if (t > t2)
k = 1.;
else k = ((double)(t - t1)) / delta_t;
x = k * (x2 - x1) + x1;
y = k * (y2 - y1) + y1;
render_context.pos_x = x;
render_context.pos_y = y;
render_context.detect_collisions = 0;
render_context.evt_type = EVENT_POSITIONED;
} else if (mystrcmp(&p, "frx") || mystrcmp(&p, "fry")) {
double val;
mystrtod(&p, &val);
mp_msg(MSGT_ASS, MSGL_V, "frx/fry unimplemented \n");
} else if (mystrcmp(&p, "frz") || mystrcmp(&p, "fr")) {
double angle;
double val;
mystrtod(&p, &val);
mp_msg(MSGT_ASS, MSGL_DBG2, "setting rotation to %.2f\n", val * pwr);
angle = M_PI * val / 180;
render_context.rotation = angle * pwr;
} else if (mystrcmp(&p, "fn")) {
char* start = p;
char* family;
skip_all('\\');
family = malloc(p - start + 1);
strncpy(family, start, p - start);
family[p - start] = '\0';
if (render_context.family)
free(render_context.family);
render_context.family = family;
update_font();
} else if (mystrcmp(&p, "alpha")) {
uint32_t val;
int i;
if (strtocolor(&p, &val)) {
unsigned char a = val >> 24;
for (i = 0; i < 4; ++i)
change_alpha(&render_context.c[i], a, pwr);
} else {
change_alpha(&render_context.c[0], render_context.style->PrimaryColour, pwr);
change_alpha(&render_context.c[1], render_context.style->SecondaryColour, pwr);
change_alpha(&render_context.c[2], render_context.style->OutlineColour, pwr);
change_alpha(&render_context.c[3], render_context.style->BackColour, pwr);
}
// FIXME: simplify
} else if (mystrcmp(&p, "an")) {
int val = strtol(p, &p, 10);
int v = (val - 1) / 3; // 0, 1 or 2 for vertical alignment
mp_msg(MSGT_ASS, MSGL_DBG2, "an %d\n", val);
if (v != 0) v = 3 - v;
val = ((val - 1) % 3) + 1; // horizontal alignment
val += v*4;
mp_msg(MSGT_ASS, MSGL_DBG2, "align %d\n", val);
render_context.alignment = val;
} else if (mystrcmp(&p, "a")) {
int val = strtol(p, &p, 10);
render_context.alignment = val;
} else if (mystrcmp(&p, "pos")) {
int v1, v2;
skip('(');
v1 = strtol(p, &p, 10);
skip(',');
v2 = strtol(p, &p, 10);
skip(')');
mp_msg(MSGT_ASS, MSGL_DBG2, "pos(%d, %d)\n", v1, v2);
render_context.evt_type = EVENT_POSITIONED;
render_context.detect_collisions = 0;
render_context.pos_x = v1;
render_context.pos_y = v2;
} else if (mystrcmp(&p, "fad")) {
int a1, a2, a3;
long long t1, t2, t3, t4;
if (*p == 'e') ++p; // either \fad or \fade
skip('(');
a1 = strtol(p, &p, 10);
skip(',');
a2 = strtol(p, &p, 10);
if (*p == ')') {
// 2-argument version (\fad, according to specs)
// a1 and a2 are fade-in and fade-out durations
t1 = 0;
t4 = render_context.event->Duration;
t2 = a1;
t3 = t4 - a2;
a1 = 0xFF;
a2 = 0;
a3 = 0xFF;
} else {
// 6-argument version (\fade)
// a1 and a2 (and a3) are opacity values
skip(',');
a3 = strtol(p, &p, 10);
skip(',');
t1 = strtoll(p, &p, 10);
skip(',');
t2 = strtoll(p, &p, 10);
skip(',');
t3 = strtoll(p, &p, 10);
skip(',');
t4 = strtoll(p, &p, 10);
}
skip(')');
render_context.fade = interpolate_alpha(frame_context.time - render_context.event->Start, t1, t2, t3, t4, a1, a2, a3);
} else if (mystrcmp(&p, "org")) {
int v1, v2;
skip('(');
v1 = strtol(p, &p, 10);
skip(',');
v2 = strtol(p, &p, 10);
skip(')');
mp_msg(MSGT_ASS, MSGL_DBG2, "org(%d, %d)\n", v1, v2);
// render_context.evt_type = EVENT_POSITIONED;
render_context.org_x = v1;
render_context.org_y = v2;
} else if (mystrcmp(&p, "t")) {
double v[3];
int v1, v2;
double v3;
int cnt;
long long t1, t2, t, delta_t;
double k;
skip('(');
for (cnt = 0; cnt < 3; ++cnt) {
if (*p == '\\')
break;
v[cnt] = strtod(p, &p);
skip(',');
}
if (cnt == 3) {
v1 = v[0]; v2 = v[1]; v3 = v[2];
} else if (cnt == 2) {
v1 = v[0]; v2 = v[1]; v3 = 1.;
} else if (cnt == 1) {
v1 = 0; v2 = render_context.event->Duration; v3 = v[0];
} else { // cnt == 0
v1 = 0; v2 = render_context.event->Duration; v3 = 1.;
}
render_context.detect_collisions = 0;
t1 = v1;
t2 = v2;
delta_t = v2 - v1;
t = frame_context.time - render_context.event->Start; // FIXME: move to render_context
if (t < t1)
k = 0.;
else if (t > t2)
k = 1.;
else k = ((double)(t - t1)) / delta_t;
while (*p == '\\')
p = parse_tag(p, k); // maybe k*pwr ? no, specs forbid nested \t's
skip_all(')'); // FIXME: better skip(')'), but much more tags support required
} else if (mystrcmp(&p, "clip")) {
int x0, y0, x1, y1;
int res = 1;
skip('(');
res &= mystrtoi(&p, 10, &x0);
skip(',');
res &= mystrtoi(&p, 10, &y0);
skip(',');
res &= mystrtoi(&p, 10, &x1);
skip(',');
res &= mystrtoi(&p, 10, &y1);
skip(')');
if (res) {
render_context.clip_x0 = render_context.clip_x0 * (1-pwr) + x0 * pwr;
render_context.clip_x1 = render_context.clip_x1 * (1-pwr) + x1 * pwr;
render_context.clip_y0 = render_context.clip_y0 * (1-pwr) + y0 * pwr;
render_context.clip_y1 = render_context.clip_y1 * (1-pwr) + y1 * pwr;
} else {
render_context.clip_x0 = 0;
render_context.clip_y0 = 0;
render_context.clip_x1 = frame_context.track->PlayResX;
render_context.clip_y1 = frame_context.track->PlayResY;
}
} else if (mystrcmp(&p, "c")) {
uint32_t val;
if (!strtocolor(&p, &val))
val = render_context.style->PrimaryColour;
mp_msg(MSGT_ASS, MSGL_DBG2, "color: %X\n", val);
change_color(&render_context.c[0], val, pwr);
} else if ((*p >= '1') && (*p <= '4') && (++p) && (mystrcmp(&p, "c") || mystrcmp(&p, "a"))) {
char n = *(p-2);
int cidx = n - '1';
char cmd = *(p-1);
uint32_t val;
assert((n >= '1') && (n <= '4'));
if (!strtocolor(&p, &val))
switch(n) {
case '1': val = render_context.style->PrimaryColour; break;
case '2': val = render_context.style->SecondaryColour; break;
case '3': val = render_context.style->OutlineColour; break;
case '4': val = render_context.style->BackColour; break;
default : val = 0; break; // impossible due to assert; avoid compilation warning
}
switch (cmd) {
case 'c': change_color(render_context.c + cidx, val, pwr); break;
case 'a': change_alpha(render_context.c + cidx, val >> 24, pwr); break;
default: mp_msg(MSGT_ASS, MSGL_WARN, "Bad command: %c%c\n", n, cmd); break;
}
mp_msg(MSGT_ASS, MSGL_DBG2, "single c/a at %f: %c%c = %X \n", pwr, n, cmd, render_context.c[cidx]);
} else if (mystrcmp(&p, "r")) {
reset_render_context();
} else if (mystrcmp(&p, "be")) {
int val;
if (mystrtoi(&p, 10, &val))
render_context.be = val ? 1 : 0;
else
render_context.be = 0;
} else if (mystrcmp(&p, "b")) {
int b;
if (mystrtoi(&p, 10, &b))
render_context.bold = b;
else
render_context.bold = - render_context.style->Bold;
update_font();
} else if (mystrcmp(&p, "i")) {
int i;
if (mystrtoi(&p, 10, &i))
render_context.italic = i;
else
render_context.italic = - render_context.style->Italic;
update_font();
} else if (mystrcmp(&p, "kf") || mystrcmp(&p, "K")) {
int val = strtol(p, &p, 10);
render_context.effect_type = EF_KARAOKE_KF;
if (render_context.effect_timing)
render_context.effect_skip_timing += render_context.effect_timing;
render_context.effect_timing = val * 10;
} else if (mystrcmp(&p, "ko")) {
int val = strtol(p, &p, 10);
render_context.effect_type = EF_KARAOKE_KO;
if (render_context.effect_timing)
render_context.effect_skip_timing += render_context.effect_timing;
render_context.effect_timing = val * 10;
} else if (mystrcmp(&p, "k")) {
int val = strtol(p, &p, 10);
render_context.effect_type = EF_KARAOKE;
if (render_context.effect_timing)
render_context.effect_skip_timing += render_context.effect_timing;
render_context.effect_timing = val * 10;
} else if (mystrcmp(&p, "shad")) {
int val;
if (mystrtoi(&p, 10, &val))
render_context.shadow = val;
else
render_context.shadow = render_context.style->Shadow;
}
return p;
#undef skip
#undef skip_all
}
/**
* \brief Get next ucs4 char from string, parsing and executing style overrides
* \param str string pointer
* \return ucs4 code of the next char
* On return str points to the unparsed part of the string
*/
static unsigned get_next_char(char** str)
{
char* p = *str;
unsigned chr;
if (*p == '{') { // '\0' goes here
p++;
while (1) {
p = parse_tag(p, 1.);
if (*p == '}') { // end of tag
p++;
if (*p == '{') {
p++;
continue;
} else
break;
} else if (*p != '\\')
mp_msg(MSGT_ASS, MSGL_V, "Unable to parse: \"%s\" \n", p);
if (*p == 0)
break;
}
}
if (*p == '\t') {
++p;
*str = p;
return ' ';
}
if (*p == '\\') {
if ((*(p+1) == 'N') || ((*(p+1) == 'n') && (frame_context.track->WrapStyle == 2))) {
p += 2;
*str = p;
return '\n';
} else if (*(p+1) == 'n') {
p += 2;
*str = p;
return ' ';
}
}
chr = utf8_get_char(&p);
*str = p;
return chr;
}
static void apply_transition_effects(ass_event_t* event)
{
int v[4];
int cnt;
char* p = event->Effect;
if (!p || !*p) return;
cnt = 0;
while (cnt < 4 && (p = strchr(p, ';'))) {
v[cnt++] = atoi(++p);
}
if (strncmp(event->Effect, "Banner;", 7) == 0) {
int delay;
if (cnt < 1) {
mp_msg(MSGT_ASS, MSGL_V, "Error parsing effect: %s \n", event->Effect);
return;
}
if (cnt >= 2 && v[1] == 0) // right-to-left
render_context.scroll_direction = SCROLL_RL;
else // left-to-right
render_context.scroll_direction = SCROLL_LR;
delay = v[0];
if (delay == 0) delay = 1; // ?
render_context.scroll_shift = (frame_context.time - render_context.event->Start) / delay;
render_context.evt_type = EVENT_HSCROLL;
return;
}
if (strncmp(event->Effect, "Scroll up;", 10) == 0) {
render_context.scroll_direction = SCROLL_BT;
} else if (strncmp(event->Effect, "Scroll down;", 12) == 0) {
render_context.scroll_direction = SCROLL_TB;
} else {
mp_msg(MSGT_ASS, MSGL_V, "Unknown transition effect: %s \n", event->Effect);
return;
}
// parse scroll up/down parameters
{
int delay;
int y0, y1;
if (cnt < 3) {
mp_msg(MSGT_ASS, MSGL_V, "Error parsing effect: %s \n", event->Effect);
return;
}
delay = v[2];
if (delay == 0) delay = 1; // ?
render_context.scroll_shift = (frame_context.time - render_context.event->Start) / delay;
if (v[0] < v[1]) {
y0 = v[0]; y1 = v[1];
} else {
y0 = v[1]; y1 = v[0];
}
if (y1 == 0)
y1 = frame_context.track->PlayResY; // y0=y1=0 means fullscreen scrolling
render_context.clip_y0 = y0;
render_context.clip_y1 = y1;
render_context.evt_type = EVENT_VSCROLL;
render_context.detect_collisions = 0;
}
}
/**
* \brief partially reset render_context to style values
* Works like {\r}: resets some style overrides
*/
static void reset_render_context(void)
{
render_context.c[0] = render_context.style->PrimaryColour;
render_context.c[1] = render_context.style->SecondaryColour;
render_context.c[2] = render_context.style->OutlineColour;
render_context.c[3] = render_context.style->BackColour;
render_context.font_size = render_context.style->FontSize;
if (render_context.family)
free(render_context.family);
render_context.family = strdup(render_context.style->FontName);
render_context.bold = - render_context.style->Bold;
render_context.italic = - render_context.style->Italic;
update_font();
change_border(-1.);
render_context.scale_x = render_context.style->ScaleX;
render_context.scale_y = render_context.style->ScaleY;
render_context.hspacing = 0; // FIXME
render_context.be = 0;
render_context.shadow = render_context.style->Shadow;
// FIXME: does not reset unsupported attributes.
}
/**
* \brief Start new event. Reset render_context.
*/
static void init_render_context(ass_event_t* event)
{
render_context.event = event;
render_context.style = frame_context.track->styles + event->Style;
reset_render_context();
render_context.evt_type = EVENT_NORMAL;
render_context.alignment = 0;
render_context.rotation = M_PI * render_context.style->Angle / 180.;
render_context.pos_x = 0;
render_context.pos_y = 0;
render_context.org_x = 0;
render_context.org_y = 0;
render_context.clip_x0 = 0;
render_context.clip_y0 = 0;
render_context.clip_x1 = frame_context.track->PlayResX;
render_context.clip_y1 = frame_context.track->PlayResY;
render_context.detect_collisions = 1;
render_context.fade = 0;
render_context.effect_type = EF_NONE;
render_context.effect_timing = 0;
render_context.effect_skip_timing = 0;
apply_transition_effects(event);
}
static void free_render_context(void)
{
}
/**
* \brief Get normal and outline glyphs from cache (if possible) or font face
* \param index face glyph index
* \param symbol ucs4 char
* \param info out: struct filled with extracted data
* \param advance advance vector of the extracted glyph
* \return 0 on success
*/
static int get_glyph(int index, int symbol, glyph_info_t* info, FT_Vector* advance)
{
int error;
glyph_hash_val_t* val;
glyph_hash_key_t* key = &(info->hash_key);
key->face = render_context.face;
key->size = render_context.font_size;
key->index = index;
key->outline = (render_context.border * 0xFFFF); // convert to 16.16
key->scale_x = (render_context.scale_x * 0xFFFF);
key->scale_y = (render_context.scale_y * 0xFFFF);
key->angle = (render_context.rotation * 0xFFFF);
key->advance = *advance;
key->bold = render_context.bold;
key->italic = render_context.italic;
key->be = render_context.be;
val = cache_find_glyph(key);
// val = 0;
if (val) {
info->glyph = info->outline_glyph = 0;
info->bm = val->bm;
info->bm_o = val->bm_o;
info->bm_s = val->bm_s;
info->bbox = val->bbox_scaled;
info->advance.x = val->advance.x;
info->advance.y = val->advance.y;
return 0;
}
// not found, get a new outline glyph from face
// mp_msg(MSGT_ASS, MSGL_INFO, "miss, index = %d, symbol = %c, adv = (%d, %d)\n", index, symbol, advance->x, advance->y);
error = FT_Load_Glyph(render_context.face, index, FT_LOAD_NO_BITMAP );
if (error) {
mp_msg(MSGT_ASS, MSGL_WARN, "Error loading glyph\n");
return error;
}
#if (FREETYPE_MAJOR > 2) || \
((FREETYPE_MAJOR == 2) && (FREETYPE_MINOR >= 2)) || \
((FREETYPE_MAJOR == 2) && (FREETYPE_MINOR == 1) && (FREETYPE_PATCH >= 10))
// FreeType >= 2.1.10 required
if (!(render_context.face->style_flags & FT_STYLE_FLAG_ITALIC) &&
((render_context.italic == 1) || (render_context.italic > 55))) {
FT_GlyphSlot_Oblique(render_context.face->glyph);
}
#endif
error = FT_Get_Glyph(render_context.face->glyph, &(info->glyph));
if (error) {
mp_msg(MSGT_ASS, MSGL_WARN, "Error getting glyph\n");
return error;
}
info->advance.x = info->glyph->advance.x >> 10;
info->advance.y = info->glyph->advance.y >> 10;
if (render_context.stroker) {
info->outline_glyph = info->glyph;
error = FT_Glyph_Stroke( &(info->outline_glyph), render_context.stroker, 0 ); // don't destroy original
if (error) {
mp_msg(MSGT_ASS, MSGL_WARN, "FT_Glyph_Stroke error %d \n", error);
}
} else {
info->outline_glyph = 0;
}
info->bm = info->bm_o = info->bm_s = 0;
return 0;
}
/**
* This function goes through text_info and calculates text parameters.
* The following text_info fields are filled:
* n_lines
* height
* lines[].height
* lines[].asc
* lines[].desc
*/
static void measure_text()
{
int cur_line = 0, max_asc = 0, max_desc = 0;
int i;
text_info.height = 0;
for (i = 0; i < text_info.length + 1; ++i) {
if ((i == text_info.length) || text_info.glyphs[i].linebreak) {
text_info.lines[cur_line].asc = max_asc;
text_info.lines[cur_line].desc = max_desc;
text_info.height += max_asc + max_desc;
cur_line ++;
max_asc = max_desc = 0;
}
if (i < text_info.length) {
glyph_info_t* cur = text_info.glyphs + i;
if (cur->asc > max_asc)
max_asc = cur->asc * render_context.scale_y;
if (cur->desc > max_desc)
max_desc = cur->desc * render_context.scale_y;
}
}
}
/**
* \brief rearrange text between lines
* \param max_text_width maximal text line width in pixels
* The algo is similar to the one in libvo/sub.c:
* 1. Place text, wrapping it when current line is full
* 2. Try moving words from the end of a line to the beginning of the next one while it reduces
* the difference in lengths between this two lines.
* The result may not be optimal, but usually is good enough.
*/
static void wrap_lines_smart(int max_text_width)
{
int i, j;
glyph_info_t *cur, *s1, *e1, *s2, *s3, *w;
int last_space;
int break_type;
int exit;
int pen_shift_x;
int pen_shift_y;
int cur_line;
last_space = -1;
text_info.n_lines = 1;
break_type = 0;
s1 = text_info.glyphs; // current line start
for (i = 0; i < text_info.length; ++i) {
int break_at, s_offset, len;
cur = text_info.glyphs + i;
break_at = -1;
s_offset = s1->bbox.xMin + s1->pos.x;
len = (cur->bbox.xMax + cur->pos.x) - s_offset;
if (cur->symbol == '\n') {
break_type = 2;
break_at = i;
mp_msg(MSGT_ASS, MSGL_DBG2, "forced line break at %d\n", break_at);
}
if (len >= max_text_width) {
break_type = 1;
break_at = last_space;
if (break_at == -1)
break_at = i - 1;
if (break_at == -1)
break_at = 0;
mp_msg(MSGT_ASS, MSGL_DBG2, "overfill at %d\n", i);
mp_msg(MSGT_ASS, MSGL_DBG2, "line break at %d\n", break_at);
}
if (break_at != -1) {
// need to use one more line
// marking break_at+1 as start of a new line
int lead = break_at + 1; // the first symbol of the new line
if (text_info.n_lines >= MAX_LINES) {
// to many lines !
// no more linebreaks
for (j = lead; j < text_info.length; ++j)
text_info.glyphs[j].linebreak = 0;
break;
}
if (lead < text_info.length)
text_info.glyphs[lead].linebreak = break_type;
last_space = -1;
s1 = text_info.glyphs + lead;
s_offset = s1->bbox.xMin + s1->pos.x;
text_info.n_lines ++;
}
if (cur->symbol == ' ')
last_space = i;
}
#define DIFF(x,y) (((x) < (y)) ? (y - x) : (x - y))
exit = 0;
while (!exit) {
exit = 1;
w = s3 = text_info.glyphs;
s1 = s2 = 0;
for (i = 0; i <= text_info.length; ++i) {
cur = text_info.glyphs + i;
if ((i == text_info.length) || cur->linebreak) {
s1 = s2;
s2 = s3;
s3 = cur;
if (s1 && (s2->linebreak == 1)) { // have at least 2 lines, and linebreak is 'soft'
int l1, l2, l1_new, l2_new;
w = s2;
do { --w; } while ((w > s1) && (w->symbol == ' '));
while ((w > s1) && (w->symbol != ' ')) { --w; }
e1 = w;
while ((e1 > s1) && (e1->symbol == ' ')) { --e1; }
if (w->symbol == ' ') ++w;
l1 = ((s2-1)->bbox.xMax + (s2-1)->pos.x) - (s1->bbox.xMin + s1->pos.x);
l2 = ((s3-1)->bbox.xMax + (s3-1)->pos.x) - (s2->bbox.xMin + s2->pos.x);
l1_new = (e1->bbox.xMax + e1->pos.x) - (s1->bbox.xMin + s1->pos.x);
l2_new = ((s3-1)->bbox.xMax + (s3-1)->pos.x) - (w->bbox.xMin + w->pos.x);
if (DIFF(l1_new, l2_new) < DIFF(l1, l2)) {
w->linebreak = 1;
s2->linebreak = 0;
exit = 0;
}
}
}
if (i == text_info.length)
break;
}
}
assert(text_info.n_lines >= 1);
#undef DIFF
measure_text();
pen_shift_x = 0;
pen_shift_y = 0;
cur_line = 1;
for (i = 0; i < text_info.length; ++i) {
cur = text_info.glyphs + i;
if (cur->linebreak) {
int height = text_info.lines[cur_line - 1].desc + text_info.lines[cur_line].asc;
cur_line ++;
pen_shift_x = - cur->pos.x;
pen_shift_y += (height >> 6) + global_settings->line_spacing;
mp_msg(MSGT_ASS, MSGL_DBG2, "shifting from %d to %d by (%d, %d)\n", i, text_info.length - 1, pen_shift_x, pen_shift_y);
}
cur->pos.x += pen_shift_x;
cur->pos.y += pen_shift_y;
}
}
/**
* \brief determine karaoke effects
* Karaoke effects cannot be calculated during parse stage (get_next_char()),
* so they are done in a separate step.
* Parse stage: when karaoke style override is found, its parameters are stored in the next glyph's
* (the first glyph of the karaoke word)'s effect_type and effect_timing.
* This function:
* 1. sets effect_type for all glyphs in the word (_karaoke_ word)
* 2. sets effect_timing for all glyphs to x coordinate of the border line between the left and right karaoke parts
* (left part is filled with PrimaryColour, right one - with SecondaryColour).
*/
static void process_karaoke_effects(void)
{
glyph_info_t *cur, *cur2;
glyph_info_t *s1, *e1; // start and end of the current word
glyph_info_t *s2; // start of the next word
int i;
int timing; // current timing
int tm_start, tm_end; // timings at start and end of the current word
int tm_current;
double dt;
int x;
int x_start, x_end;
tm_current = frame_context.time - render_context.event->Start;
timing = 0;
s1 = s2 = 0;
for (i = 0; i <= text_info.length; ++i) {
cur = text_info.glyphs + i;
if ((i == text_info.length) || (cur->effect_type != EF_NONE)) {
s1 = s2;
s2 = cur;
if (s1) {
e1 = s2 - 1;
tm_start = timing + s1->effect_skip_timing;
tm_end = tm_start + s1->effect_timing;
timing = tm_end;
x_start = 1000000;
x_end = -1000000;
for (cur2 = s1; cur2 <= e1; ++cur2) {
x_start = FFMIN(x_start, cur2->bbox.xMin + cur2->pos.x);
x_end = FFMAX(x_end, cur2->bbox.xMax + cur2->pos.x);
}
dt = (tm_current - tm_start);
if ((s1->effect_type == EF_KARAOKE) || (s1->effect_type == EF_KARAOKE_KO)) {
if (dt > 0)
x = x_end + 1;
else
x = x_start;
} else if (s1->effect_type == EF_KARAOKE_KF) {
dt /= (tm_end - tm_start);
x = x_start + (x_end - x_start) * dt;
} else {
mp_msg(MSGT_ASS, MSGL_ERR, "Unknown effect type (internal error) \n");
continue;
}
for (cur2 = s1; cur2 <= e1; ++cur2) {
cur2->effect_type = s1->effect_type;
cur2->effect_timing = x - cur2->pos.x;
}
}
}
}
}
static int get_face_ascender(FT_Face face)
{
int v = face->size->metrics.ascender;
int v2 = FT_MulFix(face->bbox.yMax, face->size->metrics.y_scale);
if (v > v2 * 0.9)
return v;
else
return v2;
}
static int get_face_descender(FT_Face face)
{
int v = - face->size->metrics.descender;
int v2 = - FT_MulFix(face->bbox.yMin, face->size->metrics.y_scale);
if (v > v2 * 0.9)
return v;
else
return v2;
}
/**
* \brief Calculate base point for positioning and rotation
* \param bbox text bbox
* \param alignment alignment
* \param bx, by out: base point coordinates
*/
static void get_base_point(FT_BBox bbox, int alignment, int* bx, int* by)
{
const int halign = alignment & 3;
const int valign = alignment & 12;
if (bx)
switch(halign) {
case HALIGN_LEFT:
*bx = bbox.xMin;
break;
case HALIGN_CENTER:
*bx = (bbox.xMax + bbox.xMin) / 2;
break;
case HALIGN_RIGHT:
*bx = bbox.xMax;
break;
}
if (by)
switch(valign) {
case VALIGN_TOP:
*by = bbox.yMin;
break;
case VALIGN_CENTER:
*by = (bbox.yMax + bbox.yMin) / 2;
break;
case VALIGN_SUB:
*by = bbox.yMax;
break;
}
}
/**
* \brief Main ass rendering function, glues everything together
* \param event event to render
* Process event, appending resulting ass_image_t's to images_root.
*/
static int ass_render_event(ass_event_t* event, event_images_t* event_images)
{
char* p;
FT_UInt glyph_index;
FT_Bool use_kerning;
FT_UInt previous;
FT_UInt num_glyphs;
FT_Vector pen;
int error;
unsigned code;
FT_BBox bbox;
int i, j;
FT_Vector shift;
int MarginL, MarginR, MarginV;
int last_break;
int alignment, halign, valign;
int device_x = 0, device_y = 0;
if (event->Style >= frame_context.track->n_styles) {
mp_msg(MSGT_ASS, MSGL_WARN, "No style found!\n");
return 1;
}
if (!event->Text) {
mp_msg(MSGT_ASS, MSGL_WARN, "Empty event!\n");
return 1;
}
init_render_context(event);
text_info.length = 0;
pen.x = 0;
pen.y = 0;
previous = 0;
num_glyphs = 0;
p = event->Text;
// Event parsing.
while (1) {
// get next char, executing style override
// this affects render_context
code = get_next_char(&p);
// face could have been changed in get_next_char
if (!render_context.face) {
free_render_context();
return 1;
}
if (code == 0)
break;
use_kerning = FT_HAS_KERNING(render_context.face);
if (text_info.length >= MAX_GLYPHS) {
mp_msg(MSGT_ASS, MSGL_WARN, "\nMAX_GLYPHS reached: event %d, start = %llu, duration = %llu\n Text = %s\n",
(int)(event - frame_context.track->events), event->Start, event->Duration, event->Text);
break;
}
glyph_index = FT_Get_Char_Index( render_context.face, code);
if ( use_kerning && previous && glyph_index ) {
FT_Vector delta;
FT_Get_Kerning( render_context.face, previous, glyph_index, FT_KERNING_DEFAULT, &delta );
pen.x += delta.x * render_context.scale_x;
pen.y += delta.y * render_context.scale_y;
}
shift.x = pen.x & 63;
shift.y = pen.y & 63;
if ((render_context.scale_x != 1.) || (render_context.scale_y != 1.) ||
(frame_context.font_scale_x != 1.)) {
FT_Matrix matrix;
matrix.xx = (FT_Fixed)( render_context.scale_x * frame_context.font_scale_x * 0x10000L );
matrix.xy = (FT_Fixed)( 0 * 0x10000L );
matrix.yx = (FT_Fixed)( 0 * 0x10000L );
matrix.yy = (FT_Fixed)( render_context.scale_y * 0x10000L );
FT_Set_Transform( render_context.face, &matrix, &shift );
} else {
FT_Set_Transform(render_context.face, 0, &shift);
}
error = get_glyph(glyph_index, code, text_info.glyphs + text_info.length, &shift);
if (error) {
continue;
}
text_info.glyphs[text_info.length].pos.x = pen.x >> 6;
text_info.glyphs[text_info.length].pos.y = pen.y >> 6;
pen.x += text_info.glyphs[text_info.length].advance.x;
pen.x += render_context.hspacing;
pen.y += text_info.glyphs[text_info.length].advance.y;
// if it's an outline glyph, we still need to fill the bbox
if (text_info.glyphs[text_info.length].glyph) {
FT_Glyph_Get_CBox( text_info.glyphs[text_info.length].glyph, FT_GLYPH_BBOX_PIXELS, &(text_info.glyphs[text_info.length].bbox) );
}
previous = glyph_index;
text_info.glyphs[text_info.length].symbol = code;
text_info.glyphs[text_info.length].linebreak = 0;
for (i = 0; i < 4; ++i) {
uint32_t clr = render_context.c[i];
change_alpha(&clr, mult_alpha(_a(clr), render_context.fade), 1.);
text_info.glyphs[text_info.length].c[i] = clr;
}
text_info.glyphs[text_info.length].effect_type = render_context.effect_type;
text_info.glyphs[text_info.length].effect_timing = render_context.effect_timing;
text_info.glyphs[text_info.length].effect_skip_timing = render_context.effect_skip_timing;
text_info.glyphs[text_info.length].asc = get_face_ascender(render_context.face);
text_info.glyphs[text_info.length].desc = get_face_descender(render_context.face);
text_info.glyphs[text_info.length].be = render_context.be;
text_info.glyphs[text_info.length].shadow = render_context.shadow;
text_info.glyphs[text_info.length].frz = render_context.rotation;
text_info.length++;
render_context.effect_type = EF_NONE;
render_context.effect_timing = 0;
render_context.effect_skip_timing = 0;
}
if (text_info.length == 0) {
// no valid symbols in the event; this can be smth like {comment}
free_render_context();
return 1;
}
// depends on glyph x coordinates being monotonous, so it should be done before line wrap
process_karaoke_effects();
// alignments
alignment = render_context.alignment;
if (!alignment)
alignment = render_context.style->Alignment;
halign = alignment & 3;
valign = alignment & 12;
MarginL = (event->MarginL) ? event->MarginL : render_context.style->MarginL;
MarginR = (event->MarginR) ? event->MarginR : render_context.style->MarginR;
MarginV = (event->MarginV) ? event->MarginV : render_context.style->MarginV;
if (render_context.evt_type != EVENT_HSCROLL) {
int max_text_width;
// calculate max length of a line
max_text_width = x2scr(frame_context.track->PlayResX - MarginR) - x2scr(MarginL);
// rearrange text in several lines
wrap_lines_smart(max_text_width);
// align text
last_break = -1;
for (i = 1; i < text_info.length + 1; ++i) { // (text_info.length + 1) is the end of the last line
if ((i == text_info.length) || text_info.glyphs[i].linebreak) {
int width, shift;
glyph_info_t* first_glyph = text_info.glyphs + last_break + 1;
glyph_info_t* last_glyph = text_info.glyphs + i - 1;
while ((last_glyph > first_glyph) && ((last_glyph->symbol == '\n') || (last_glyph->symbol == 0)))
last_glyph --;
width = last_glyph->pos.x + last_glyph->bbox.xMax - first_glyph->pos.x - first_glyph->bbox.xMin;
shift = - first_glyph->bbox.xMin; // now text line starts exactly at 0 (left margin)
if (halign == HALIGN_LEFT) { // left aligned, no action
} else if (halign == HALIGN_RIGHT) { // right aligned
shift = max_text_width - width;
} else if (halign == HALIGN_CENTER) { // centered
shift = (max_text_width - width) / 2;
}
for (j = last_break + 1; j < i; ++j) {
text_info.glyphs[j].pos.x += shift;
}
last_break = i - 1;
}
}
} else { // render_context.evt_type == EVENT_HSCROLL
measure_text();
}
// determing text bounding box
compute_string_bbox(&text_info, &bbox);
bbox.yMin = - (text_info.lines[0].asc >> 6);
bbox.yMax = (text_info.height - text_info.lines[0].asc) >> 6;
// determine device coordinates for text
// x coordinate for everything except positioned events
if (render_context.evt_type == EVENT_NORMAL ||
render_context.evt_type == EVENT_VSCROLL) {
device_x = x2scr(MarginL);
} else if (render_context.evt_type == EVENT_HSCROLL) {
if (render_context.scroll_direction == SCROLL_RL)
device_x = x2scr(frame_context.track->PlayResX - render_context.scroll_shift);
else if (render_context.scroll_direction == SCROLL_LR)
device_x = x2scr(render_context.scroll_shift) - (bbox.xMax - bbox.xMin);
}
// y coordinate for everything except positioned events
if (render_context.evt_type == EVENT_NORMAL ||
render_context.evt_type == EVENT_HSCROLL) {
if (valign == VALIGN_TOP) { // toptitle
device_y = y2scr_top(MarginV) + (text_info.lines[0].asc >> 6);
} else if (valign == VALIGN_CENTER) { // midtitle
int scr_y = y2scr(frame_context.track->PlayResY / 2);
device_y = scr_y - (bbox.yMax - bbox.yMin) / 2;
} else { // subtitle
int scr_y;
if (valign != VALIGN_SUB)
mp_msg(MSGT_ASS, MSGL_V, "Invalid valign, supposing 0 (subtitle)\n");
scr_y = y2scr_sub(frame_context.track->PlayResY - MarginV);
device_y = scr_y;
device_y -= (text_info.height >> 6);
device_y += (text_info.lines[0].asc >> 6);
}
} else if (render_context.evt_type == EVENT_VSCROLL) {
if (render_context.scroll_direction == SCROLL_TB)
device_y = y2scr(render_context.clip_y0 + render_context.scroll_shift) - (bbox.yMax - bbox.yMin);
else if (render_context.scroll_direction == SCROLL_BT)
device_y = y2scr(render_context.clip_y1 - render_context.scroll_shift);
}
// positioned events are totally different
if (render_context.evt_type == EVENT_POSITIONED) {
int base_x = 0;
int base_y = 0;
mp_msg(MSGT_ASS, MSGL_DBG2, "positioned event at %d, %d\n", render_context.pos_x, render_context.pos_y);
get_base_point(bbox, alignment, &base_x, &base_y);
device_x = x2scr(render_context.pos_x) - base_x;
device_y = y2scr(render_context.pos_y) - base_y;
}
// fix clip coordinates (they depend on alignment)
render_context.clip_x0 = x2scr(render_context.clip_x0);
render_context.clip_x1 = x2scr(render_context.clip_x1);
if (render_context.evt_type == EVENT_NORMAL ||
render_context.evt_type == EVENT_HSCROLL ||
render_context.evt_type == EVENT_VSCROLL) {
if (valign == VALIGN_TOP) {
render_context.clip_y0 = y2scr_top(render_context.clip_y0);
render_context.clip_y1 = y2scr_top(render_context.clip_y1);
} else if (valign == VALIGN_CENTER) {
render_context.clip_y0 = y2scr(render_context.clip_y0);
render_context.clip_y1 = y2scr(render_context.clip_y1);
} else if (valign == VALIGN_SUB) {
render_context.clip_y0 = y2scr_sub(render_context.clip_y0);
render_context.clip_y1 = y2scr_sub(render_context.clip_y1);
}
} else if (render_context.evt_type == EVENT_POSITIONED) {
render_context.clip_y0 = y2scr(render_context.clip_y0);
render_context.clip_y1 = y2scr(render_context.clip_y1);
}
// rotate glyphs if needed
{
double angle = 0.;
FT_Vector center;
FT_Matrix matrix_rotate;
if (((render_context.org_x != 0) || (render_context.org_y != 0)) && (render_context.evt_type == EVENT_POSITIONED)) {
center.x = render_context.org_x;
center.y = render_context.org_y;
} else {
int bx, by;
get_base_point(bbox, alignment, &bx, &by);
center.x = device_x + bx;
center.y = device_y + by;
}
for (i = 0; i < text_info.length; ++i) {
FT_Vector start;
FT_Vector start_old;
glyph_info_t* info = text_info.glyphs + i;
if (info->frz < 0.00001 && info->frz > -0.00001)
continue;
if (info->frz != angle) {
angle = info->frz;
matrix_rotate.xx = (FT_Fixed)( cos( angle ) * 0x10000L );
matrix_rotate.xy = (FT_Fixed)( -sin( angle ) * 0x10000L );
matrix_rotate.yx = (FT_Fixed)( sin( angle ) * 0x10000L );
matrix_rotate.yy = (FT_Fixed)( cos( angle ) * 0x10000L );
}
// calculating shift vector
// shift = (position - center)*M - (position - center)
start.x = (info->pos.x + device_x - center.x) << 6;
start.y = - (info->pos.y + device_y - center.y) << 6;
start_old.x = start.x;
start_old.y = start.y;
FT_Vector_Transform(&start, &matrix_rotate);
start.x -= start_old.x;
start.y -= start_old.y;
info->pos.x += start.x >> 6;
info->pos.y -= start.y >> 6;
if (info->glyph)
FT_Glyph_Transform( info->glyph, &matrix_rotate, 0 );
if (info->outline_glyph)
FT_Glyph_Transform( info->outline_glyph, &matrix_rotate, 0 );
}
}
event_images->top = device_y - (text_info.lines[0].asc >> 6);
event_images->height = text_info.height >> 6;
event_images->detect_collisions = render_context.detect_collisions;
event_images->shift_direction = (valign == VALIGN_TOP) ? 1 : -1;
event_images->event = event;
event_images->imgs = render_text(&text_info, device_x, device_y);
free_render_context();
return 0;
}
static void ass_reconfigure(ass_renderer_t* priv)
{
priv->render_id = ++last_render_id;
ass_glyph_cache_reset();
}
void ass_set_frame_size(ass_renderer_t* priv, int w, int h)
{
if (priv->settings.frame_width != w || priv->settings.frame_height != h) {
priv->settings.frame_width = w;
priv->settings.frame_height = h;
if (priv->settings.aspect == 0.)
priv->settings.aspect = ((double)w) / h;
ass_reconfigure(priv);
}
}
void ass_set_margins(ass_renderer_t* priv, int t, int b, int l, int r)
{
if (priv->settings.left_margin != l ||
priv->settings.right_margin != r ||
priv->settings.top_margin != t ||
priv->settings.bottom_margin != b) {
priv->settings.left_margin = l;
priv->settings.right_margin = r;
priv->settings.top_margin = t;
priv->settings.bottom_margin = b;
ass_reconfigure(priv);
}
}
void ass_set_use_margins(ass_renderer_t* priv, int use)
{
priv->settings.use_margins = use;
}
void ass_set_aspect_ratio(ass_renderer_t* priv, double ar)
{
if (priv->settings.aspect != ar) {
priv->settings.aspect = ar;
ass_reconfigure(priv);
}
}
void ass_set_font_scale(ass_renderer_t* priv, double font_scale)
{
if (priv->settings.font_size_coeff != font_scale) {
priv->settings.font_size_coeff = font_scale;
ass_reconfigure(priv);
}
}
int ass_set_fonts(ass_renderer_t* priv, const char* default_font, const char* default_family)
{
if (priv->settings.default_font)
free(priv->settings.default_font);
if (priv->settings.default_family)
free(priv->settings.default_family);
priv->settings.default_font = default_font ? strdup(default_font) : 0;
priv->settings.default_family = default_family ? strdup(default_family) : 0;
if (priv->fontconfig_priv)
fontconfig_done(priv->fontconfig_priv);
priv->fontconfig_priv = fontconfig_init(priv->library->fonts_dir, default_family, default_font);
return !!priv->fontconfig_priv;
}
/**
* \brief Start a new frame
*/
static int ass_start_frame(ass_renderer_t *priv, ass_track_t* track, long long now)
{
ass_image_t* img;
ass_renderer = priv;
global_settings = &priv->settings;
if (!priv->settings.frame_width && !priv->settings.frame_height)
return 1; // library not initialized
frame_context.ass_priv = priv;
frame_context.width = global_settings->frame_width;
frame_context.height = global_settings->frame_height;
frame_context.orig_width = global_settings->frame_width - global_settings->left_margin - global_settings->right_margin;
frame_context.orig_height = global_settings->frame_height - global_settings->top_margin - global_settings->bottom_margin;
frame_context.track = track;
frame_context.time = now;
ass_lazy_track_init();
frame_context.font_scale = global_settings->font_size_coeff * ass_internal_font_size_coeff *
frame_context.orig_height / frame_context.track->PlayResY;
frame_context.border_scale = ((double)frame_context.orig_height) / frame_context.track->PlayResY;
if (frame_context.orig_width * track->PlayResY == frame_context.orig_height * track->PlayResX)
frame_context.font_scale_x = 1.;
else
frame_context.font_scale_x = ((double)(frame_context.orig_width * track->PlayResY)) / (frame_context.orig_height * track->PlayResX);
img = priv->images_root;
while (img) {
ass_image_t* next = img->next;
free(img);
img = next;
}
priv->images_root = 0;
return 0;
}
static int cmp_event_layer(const void* p1, const void* p2)
{
ass_event_t* e1 = ((event_images_t*)p1)->event;
ass_event_t* e2 = ((event_images_t*)p2)->event;
if (e1->Layer < e2->Layer)
return -1;
if (e1->Layer > e2->Layer)
return 1;
if (e1->Start < e2->Start)
return -1;
if (e1->Start > e2->Start)
return 1;
if (e1->ReadOrder < e2->ReadOrder)
return -1;
if (e1->ReadOrder > e2->ReadOrder)
return 1;
return 0;
}
#define MAX_EVENTS 100
static render_priv_t* get_render_priv(ass_event_t* event)
{
if (!event->render_priv)
event->render_priv = calloc(1, sizeof(render_priv_t));
// FIXME: check render_id
if (ass_renderer->render_id != event->render_priv->render_id) {
memset(event->render_priv, 0, sizeof(render_priv_t));
event->render_priv->render_id = ass_renderer->render_id;
}
return event->render_priv;
}
typedef struct segment_s {
int a, b; // top and height
} segment_t;
static int overlap(segment_t* s1, segment_t* s2)
{
if (s1->a >= s2->b || s2->a >= s1->b)
return 0;
return 1;
}
static int cmp_segment(const void* p1, const void* p2)
{
return ((segment_t*)p1)->a - ((segment_t*)p2)->a;
}
static void shift_event(event_images_t* ei, int shift)
{
ass_image_t* cur = ei->imgs;
while (cur) {
cur->dst_y += shift;
// clip top and bottom
if (cur->dst_y < 0) {
int clip = - cur->dst_y;
cur->h -= clip;
cur->bitmap += clip * cur->stride;
cur->dst_y = 0;
}
if (cur->dst_y + cur->h >= frame_context.height) {
int clip = cur->dst_y + cur->h - frame_context.height;
cur->h -= clip;
}
if (cur->h <= 0) {
cur->h = 0;
cur->dst_y = 0;
}
cur = cur->next;
}
ei->top += shift;
}
// dir: 1 - move down
// -1 - move up
static int fit_segment(segment_t* s, segment_t* fixed, int* cnt, int dir)
{
int i;
int shift;
if (*cnt == 0) {
*cnt = 1;
fixed[0].a = s->a;
fixed[0].b = s->b;
return 0;
}
if (dir == 1) { // move down
if (s->b <= fixed[0].a) // all ok
return 0;
for (i = 0; i < *cnt; ++i) {
shift = fixed[i].b - s->a;
if (i == *cnt - 1 || fixed[i+1].a >= shift + s->b) { // here is a good place
fixed[i].b += s->b - s->a;
return shift;
}
}
} else { // dir == -1, move up
if (s->a >= fixed[*cnt-1].b) // all ok
return 0;
for (i = *cnt-1; i >= 0; --i) {
shift = fixed[i].a - s->b;
if (i == 0 || fixed[i-1].b <= shift + s->a) { // here is a good place
fixed[i].a -= s->b - s->a;
return shift;
}
}
}
assert(0); // unreachable
}
static void fix_collisions(event_images_t* imgs, int cnt)
{
segment_t used[MAX_EVENTS];
int cnt_used = 0;
int i, j;
// fill used[] with fixed events
for (i = 0; i < cnt; ++i) {
render_priv_t* priv;
if (!imgs[i].detect_collisions) break;
priv = get_render_priv(imgs[i].event);
if (priv->height > 0) { // it's a fixed event
segment_t s;
s.a = priv->top;
s.b = priv->top + priv->height;
if (priv->height != imgs[i].height) { // no, it's not
mp_msg(MSGT_ASS, MSGL_WARN, "Achtung! Event height has changed! \n");
priv->top = 0;
priv->height = 0;
}
for (j = 0; j < cnt_used; ++j)
if (overlap(&s, used + j)) { // no, it's not
priv->top = 0;
priv->height = 0;
}
if (priv->height > 0) { // still a fixed event
used[cnt_used].a = priv->top;
used[cnt_used].b = priv->top + priv->height;
cnt_used ++;
shift_event(imgs + i, priv->top - imgs[i].top);
}
}
}
qsort(used, cnt_used, sizeof(segment_t), cmp_segment);
// try to fit other events in free spaces
for (i = 0; i < cnt; ++i) {
render_priv_t* priv;
if (!imgs[i].detect_collisions) break;
priv = get_render_priv(imgs[i].event);
if (priv->height == 0) { // not a fixed event
int shift;
segment_t s;
s.a = imgs[i].top;
s.b = imgs[i].top + imgs[i].height;
shift = fit_segment(&s, used, &cnt_used, imgs[i].shift_direction);
if (shift) shift_event(imgs + i, shift);
// make it fixed
priv->top = imgs[i].top;
priv->height = imgs[i].height;
}
}
}
/**
* \brief render a frame
* \param priv library handle
* \param track track
* \param now current video timestamp (ms)
*/
ass_image_t* ass_render_frame(ass_renderer_t *priv, ass_track_t* track, long long now)
{
int i, cnt, rc;
event_images_t eimg[MAX_EVENTS];
event_images_t* last;
ass_image_t** tail;
// init frame
rc = ass_start_frame(priv, track, now);
if (rc != 0)
return 0;
// render events separately
cnt = 0;
for (i = 0; i < track->n_events; ++i) {
ass_event_t* event = track->events + i;
if ( (event->Start <= now) && (now < (event->Start + event->Duration)) ) {
if (cnt < MAX_EVENTS) {
rc = ass_render_event(event, eimg + cnt);
if (!rc) ++cnt;
} else {
mp_msg(MSGT_ASS, MSGL_WARN, "Too many simultaneous events \n");
break;
}
}
}
// sort by layer
qsort(eimg, cnt, sizeof(event_images_t), cmp_event_layer);
// call fix_collisions for each group of events with the same layer
last = eimg;
for (i = 1; i < cnt; ++i)
if (last->event->Layer != eimg[i].event->Layer) {
fix_collisions(last, eimg + i - last);
last = eimg + i;
}
if (cnt > 0)
fix_collisions(last, eimg + cnt - last);
// concat lists
tail = &ass_renderer->images_root;
for (i = 0; i < cnt; ++i) {
ass_image_t* cur = eimg[i].imgs;
while (cur) {
*tail = cur;
tail = &cur->next;
cur = cur->next;
}
}
return ass_renderer->images_root;
}
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