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mirror of https://github.com/mpv-player/mpv.git synced 2024-09-20 12:02:23 +02:00
mpv/sub/sd_ass.c
Dudemanguy 4e5d996c3a player/sub: attempt to detect animated subtitles
The previous commits optimized sub redrawing on still images/terminal so
mpv wouldn't redraw so much. There is a gap though. It only assumes
static subtitles. Since ASS can be animated, those types of subtitles
will always need redraws so we need to build in specific detection for
this. We need to build a whitelist of events in ASS that are considered
animations and then flag the packet. Additionally, there's a bunch of
annoying bookkeeping that has to be done since packets can be dropped on
seeks and so on.
2024-02-15 16:43:11 +00:00

1098 lines
36 KiB
C

/*
* This file is part of mpv.
*
* mpv 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.
*
* mpv 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 mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdlib.h>
#include <assert.h>
#include <string.h>
#include <math.h>
#include <limits.h>
#include <libavutil/common.h>
#include <ass/ass.h>
#include "mpv_talloc.h"
#include "config.h"
#include "options/m_config.h"
#include "options/options.h"
#include "common/common.h"
#include "common/msg.h"
#include "demux/demux.h"
#include "video/csputils.h"
#include "video/mp_image.h"
#include "dec_sub.h"
#include "ass_mp.h"
#include "sd.h"
struct sd_ass_priv {
struct ass_library *ass_library;
struct ass_renderer *ass_renderer;
struct ass_track *ass_track;
struct ass_track *shadow_track; // for --sub-ass=no rendering
bool ass_configured;
bool is_converted;
struct lavc_conv *converter;
struct sd_filter **filters;
int num_filters;
bool clear_once;
struct mp_ass_packer *packer;
struct sub_bitmap_copy_cache *copy_cache;
char last_text[500];
struct mp_image_params video_params;
struct mp_image_params last_params;
struct mp_osd_res osd;
int64_t *seen_packets;
int num_seen_packets;
bool *packets_animated;
int num_packets_animated;
bool duration_unknown;
};
static void mangle_colors(struct sd *sd, struct sub_bitmaps *parts);
static void fill_plaintext(struct sd *sd, double pts);
static const struct sd_filter_functions *const filters[] = {
// Note: list order defines filter order.
&sd_filter_sdh,
#if HAVE_POSIX
&sd_filter_regex,
#endif
#if HAVE_JAVASCRIPT
&sd_filter_jsre,
#endif
NULL,
};
// Add default styles, if the track does not have any styles yet.
// Apply style overrides if the user provides any.
static void mp_ass_add_default_styles(ASS_Track *track, struct mp_subtitle_opts *opts,
struct mp_subtitle_shared_opts *shared_opts, int order)
{
if (opts->ass_styles_file && shared_opts->ass_style_override[order])
ass_read_styles(track, opts->ass_styles_file, NULL);
if (track->n_styles == 0) {
if (!track->PlayResY) {
track->PlayResX = MP_ASS_FONT_PLAYRESX;
track->PlayResY = MP_ASS_FONT_PLAYRESY;
}
track->Kerning = true;
int sid = ass_alloc_style(track);
track->default_style = sid;
ASS_Style *style = track->styles + sid;
style->Name = strdup("Default");
mp_ass_set_style(style, track->PlayResY, opts->sub_style);
}
if (shared_opts->ass_style_override[order])
ass_process_force_style(track);
}
static const char *const font_mimetypes[] = {
"application/x-truetype-font",
"application/vnd.ms-opentype",
"application/x-font-ttf",
"application/x-font", // probably incorrect
"application/font-sfnt",
"font/collection",
"font/otf",
"font/sfnt",
"font/ttf",
NULL
};
static const char *const font_exts[] = {".ttf", ".ttc", ".otf", ".otc", NULL};
static bool attachment_is_font(struct mp_log *log, struct demux_attachment *f)
{
if (!f->name || !f->type || !f->data || !f->data_size)
return false;
for (int n = 0; font_mimetypes[n]; n++) {
if (strcmp(font_mimetypes[n], f->type) == 0)
return true;
}
// fallback: match against file extension
char *ext = strlen(f->name) > 4 ? f->name + strlen(f->name) - 4 : "";
for (int n = 0; font_exts[n]; n++) {
if (strcasecmp(ext, font_exts[n]) == 0) {
mp_warn(log, "Loading font attachment '%s' with MIME type %s. "
"Assuming this is a broken Matroska file, which was "
"muxed without setting a correct font MIME type.\n",
f->name, f->type);
return true;
}
}
return false;
}
static void add_subtitle_fonts(struct sd *sd)
{
struct sd_ass_priv *ctx = sd->priv;
struct mp_subtitle_opts *opts = sd->opts;
if (!opts->ass_enabled || !opts->use_embedded_fonts || !sd->attachments)
return;
for (int i = 0; i < sd->attachments->num_entries; i++) {
struct demux_attachment *f = &sd->attachments->entries[i];
if (attachment_is_font(sd->log, f))
ass_add_font(ctx->ass_library, f->name, f->data, f->data_size);
}
}
static void filters_destroy(struct sd *sd)
{
struct sd_ass_priv *ctx = sd->priv;
for (int n = 0; n < ctx->num_filters; n++) {
struct sd_filter *ft = ctx->filters[n];
if (ft->driver->uninit)
ft->driver->uninit(ft);
talloc_free(ft);
}
ctx->num_filters = 0;
}
static void filters_init(struct sd *sd)
{
struct sd_ass_priv *ctx = sd->priv;
filters_destroy(sd);
for (int n = 0; filters[n]; n++) {
struct sd_filter *ft = talloc_ptrtype(ctx, ft);
*ft = (struct sd_filter){
.global = sd->global,
.log = sd->log,
.opts = mp_get_config_group(ft, sd->global, &mp_sub_filter_opts),
.driver = filters[n],
.codec = "ass",
.event_format = ctx->ass_track->event_format,
};
if (ft->driver->init(ft)) {
MP_TARRAY_APPEND(ctx, ctx->filters, ctx->num_filters, ft);
} else {
talloc_free(ft);
}
}
}
static void enable_output(struct sd *sd, bool enable)
{
struct sd_ass_priv *ctx = sd->priv;
if (enable == !!ctx->ass_renderer)
return;
if (ctx->ass_renderer) {
ass_renderer_done(ctx->ass_renderer);
ctx->ass_renderer = NULL;
} else {
ctx->ass_renderer = ass_renderer_init(ctx->ass_library);
mp_ass_configure_fonts(ctx->ass_renderer, sd->opts->sub_style,
sd->global, sd->log);
}
}
static void assobjects_init(struct sd *sd)
{
struct sd_ass_priv *ctx = sd->priv;
struct mp_subtitle_opts *opts = sd->opts;
struct mp_subtitle_shared_opts *shared_opts = sd->shared_opts;
ctx->ass_library = mp_ass_init(sd->global, sd->opts->sub_style, sd->log);
ass_set_extract_fonts(ctx->ass_library, opts->use_embedded_fonts);
add_subtitle_fonts(sd);
if (shared_opts->ass_style_override[sd->order])
ass_set_style_overrides(ctx->ass_library, opts->ass_style_override_list);
ctx->ass_track = ass_new_track(ctx->ass_library);
ctx->ass_track->track_type = TRACK_TYPE_ASS;
ctx->shadow_track = ass_new_track(ctx->ass_library);
ctx->shadow_track->PlayResX = MP_ASS_FONT_PLAYRESX;
ctx->shadow_track->PlayResY = MP_ASS_FONT_PLAYRESY;
mp_ass_add_default_styles(ctx->shadow_track, opts, shared_opts, sd->order);
char *extradata = sd->codec->extradata;
int extradata_size = sd->codec->extradata_size;
if (ctx->converter) {
extradata = lavc_conv_get_extradata(ctx->converter);
extradata_size = extradata ? strlen(extradata) : 0;
}
if (extradata)
ass_process_codec_private(ctx->ass_track, extradata, extradata_size);
mp_ass_add_default_styles(ctx->ass_track, opts, shared_opts, sd->order);
#if LIBASS_VERSION >= 0x01302000
ass_set_check_readorder(ctx->ass_track, sd->opts->sub_clear_on_seek ? 0 : 1);
#endif
enable_output(sd, true);
}
static void assobjects_destroy(struct sd *sd)
{
struct sd_ass_priv *ctx = sd->priv;
ass_free_track(ctx->ass_track);
ass_free_track(ctx->shadow_track);
enable_output(sd, false);
ass_library_done(ctx->ass_library);
}
static int init(struct sd *sd)
{
struct sd_ass_priv *ctx = talloc_zero(sd, struct sd_ass_priv);
sd->priv = ctx;
// Note: accept "null" as alias for "ass", so EDL delay_open subtitle
// streams work.
if (strcmp(sd->codec->codec, "ass") != 0 &&
strcmp(sd->codec->codec, "null") != 0)
{
ctx->is_converted = true;
ctx->converter = lavc_conv_create(sd->log, sd->codec);
if (!ctx->converter)
return -1;
if (strcmp(sd->codec->codec, "eia_608") == 0)
ctx->duration_unknown = 1;
}
assobjects_init(sd);
filters_init(sd);
ctx->packer = mp_ass_packer_alloc(ctx);
return 0;
}
// Check if subtitle has events that would cause it to be animated inside {}
static bool is_animated(char *s)
{
bool in_tag = false;
bool valid_event = false;
bool valid_tag = false;
while (*s) {
if (!in_tag && s[0] == '{')
in_tag = true;
if (s[0] == '\\') {
s++;
if (!s[0])
break;
if (s[0] == 'k' || s[0] == 'K' || s[0] == 't') {
valid_event = true;
continue;
// just bruteforce the multi-letter ones
} else if (s[0] == 'f') {
if (!strncmp(s, "fad", 3)) {
valid_event = true;
continue;
}
} else if (s[0] == 'm') {
if (!strncmp(s, "move", 4)) {
valid_event = true;
continue;
}
}
}
if (in_tag && valid_event && s[0] == '}') {
valid_tag = true;
break;
} else if (s[0] == '}') {
in_tag = false;
valid_event = false;
valid_tag = false;
}
s++;
}
return valid_tag;
}
// Note: pkt is not necessarily a fully valid refcounted packet.
static void filter_and_add(struct sd *sd, struct demux_packet *pkt)
{
struct sd_ass_priv *ctx = sd->priv;
struct demux_packet *orig_pkt = pkt;
ASS_Track *track = ctx->ass_track;
int old_n_events = track->n_events;
for (int n = 0; n < ctx->num_filters; n++) {
struct sd_filter *ft = ctx->filters[n];
struct demux_packet *npkt = ft->driver->filter(ft, pkt);
if (pkt != npkt && pkt != orig_pkt)
talloc_free(pkt);
pkt = npkt;
if (!pkt)
return;
}
ass_process_chunk(ctx->ass_track, pkt->buffer, pkt->len,
llrint(pkt->pts * 1000),
llrint(pkt->duration * 1000));
// This bookkeeping is only ever needed for ASS subs
if (!ctx->is_converted) {
if (!pkt->seen) {
for (int n = track->n_events - 1; n >= 0; n--) {
if (n + 1 == old_n_events || pkt->animated)
break;
ASS_Event *event = &track->events[n];
pkt->animated = (event->Effect && event->Effect[0]) ||
is_animated(event->Text);
}
MP_TARRAY_APPEND(ctx, ctx->packets_animated, ctx->num_packets_animated, pkt->animated);
} else {
pkt->animated = ctx->packets_animated[pkt->seen_pos];
}
}
if (pkt != orig_pkt)
talloc_free(pkt);
}
// Test if the packet with the given file position (used as unique ID) was
// already consumed. Return false if the packet is new (and add it to the
// internal list), and return true if it was already seen.
static bool check_packet_seen(struct sd *sd, struct demux_packet *packet)
{
struct sd_ass_priv *priv = sd->priv;
int a = 0;
int b = priv->num_seen_packets;
while (a < b) {
int mid = a + (b - a) / 2;
int64_t val = priv->seen_packets[mid];
if (packet->pos == val) {
packet->seen_pos = mid;
return true;
}
if (packet->pos > val) {
a = mid + 1;
} else {
b = mid;
}
}
packet->seen_pos = a;
MP_TARRAY_INSERT_AT(priv, priv->seen_packets, priv->num_seen_packets, a, packet->pos);
return false;
}
#define UNKNOWN_DURATION (INT_MAX / 1000)
static void decode(struct sd *sd, struct demux_packet *packet)
{
struct sd_ass_priv *ctx = sd->priv;
ASS_Track *track = ctx->ass_track;
packet->sub_duration = packet->duration;
if (ctx->converter) {
if (!sd->opts->sub_clear_on_seek && packet->pos >= 0 &&
check_packet_seen(sd, packet))
return;
double sub_pts = 0;
double sub_duration = 0;
char **r = lavc_conv_decode(ctx->converter, packet, &sub_pts,
&sub_duration);
if (sd->opts->sub_stretch_durations ||
packet->duration < 0 || sub_duration == UINT32_MAX) {
if (!ctx->duration_unknown) {
MP_WARN(sd, "Subtitle with unknown duration.\n");
ctx->duration_unknown = true;
}
sub_duration = UNKNOWN_DURATION;
}
for (int n = 0; r && r[n]; n++) {
struct demux_packet pkt2 = {
.pts = sub_pts,
.duration = sub_duration,
.buffer = r[n],
.len = strlen(r[n]),
};
filter_and_add(sd, &pkt2);
}
if (ctx->duration_unknown) {
for (int n = track->n_events - 2; n >= 0; n--) {
if (track->events[n].Duration == UNKNOWN_DURATION * 1000) {
if (track->events[n].Start != track->events[n + 1].Start) {
track->events[n].Duration = track->events[n + 1].Start -
track->events[n].Start;
} else {
track->events[n].Duration = track->events[n + 1].Duration;
}
}
}
}
} else {
// Note that for this packet format, libass has an internal mechanism
// for discarding duplicate (already seen) packets but we check this
// anyways for our purposes for ASS subtitles.
packet->seen = check_packet_seen(sd, packet);
filter_and_add(sd, packet);
}
}
static void configure_ass(struct sd *sd, struct mp_osd_res *dim,
bool converted, ASS_Track *track)
{
struct mp_subtitle_opts *opts = sd->opts;
struct mp_subtitle_shared_opts *shared_opts = sd->shared_opts;
struct sd_ass_priv *ctx = sd->priv;
ASS_Renderer *priv = ctx->ass_renderer;
ass_set_frame_size(priv, dim->w, dim->h);
ass_set_margins(priv, dim->mt, dim->mb, dim->ml, dim->mr);
bool set_use_margins = false;
float set_sub_pos = 0.0f;
float set_line_spacing = 0;
float set_font_scale = 1;
int set_hinting = 0;
bool set_scale_with_window = false;
bool set_scale_by_window = true;
bool total_override = false;
// With forced overrides, apply the --sub-* specific options
if (converted || shared_opts->ass_style_override[sd->order] == 3) { // 'force'
set_scale_with_window = opts->sub_scale_with_window;
set_use_margins = opts->sub_use_margins;
set_scale_by_window = opts->sub_scale_by_window;
total_override = true;
} else {
set_scale_with_window = opts->ass_scale_with_window;
set_use_margins = opts->ass_use_margins;
}
if (converted || shared_opts->ass_style_override[sd->order]) {
set_sub_pos = 100.0f - shared_opts->sub_pos[sd->order];
set_line_spacing = opts->ass_line_spacing;
set_hinting = opts->ass_hinting;
set_font_scale = opts->sub_scale;
}
if (set_scale_with_window) {
int vidh = dim->h - (dim->mt + dim->mb);
set_font_scale *= dim->h / (float)MPMAX(vidh, 1);
}
if (!set_scale_by_window) {
double factor = dim->h / 720.0;
if (factor != 0.0)
set_font_scale /= factor;
}
ass_set_use_margins(priv, set_use_margins);
ass_set_line_position(priv, set_sub_pos);
ass_set_shaper(priv, opts->ass_shaper);
int set_force_flags = 0;
if (total_override)
set_force_flags |= ASS_OVERRIDE_BIT_STYLE | ASS_OVERRIDE_BIT_SELECTIVE_FONT_SCALE;
if (shared_opts->ass_style_override[sd->order] == 4) // 'scale'
set_force_flags |= ASS_OVERRIDE_BIT_SELECTIVE_FONT_SCALE;
if (converted)
set_force_flags |= ASS_OVERRIDE_BIT_ALIGNMENT;
#ifdef ASS_JUSTIFY_AUTO
if ((converted || shared_opts->ass_style_override[sd->order]) && opts->ass_justify)
set_force_flags |= ASS_OVERRIDE_BIT_JUSTIFY;
#endif
ass_set_selective_style_override_enabled(priv, set_force_flags);
ASS_Style style = {0};
mp_ass_set_style(&style, MP_ASS_FONT_PLAYRESY, opts->sub_style);
ass_set_selective_style_override(priv, &style);
free(style.FontName);
if (converted && track->default_style < track->n_styles) {
mp_ass_set_style(track->styles + track->default_style,
track->PlayResY, opts->sub_style);
}
ass_set_font_scale(priv, set_font_scale);
ass_set_hinting(priv, set_hinting);
ass_set_line_spacing(priv, set_line_spacing);
#if LIBASS_VERSION >= 0x01600010
if (converted)
ass_track_set_feature(track, ASS_FEATURE_WRAP_UNICODE, 1);
#endif
if (converted) {
bool override_playres = true;
char **ass_style_override_list = opts->ass_style_override_list;
for (int i = 0; ass_style_override_list && ass_style_override_list[i]; i++) {
if (bstr_find0(bstr0(ass_style_override_list[i]), "PlayResX") >= 0)
override_playres = false;
}
// srt to ass conversion from ffmpeg has fixed PlayResX of 384 with an
// aspect of 4:3. Starting with libass f08f8ea5 (pre 0.17) PlayResX
// affects shadow and border widths, among others, so to render borders
// and shadows correctly, we adjust PlayResX according to the DAR.
// But PlayResX also affects margins, so we adjust those too.
// This should ensure basic srt-to-ass ffmpeg conversion has correct
// borders, but there could be other issues with some srt extensions
// and/or different source formats which would be exposed over time.
// Make these adjustments only if the user didn't set PlayResX.
if (override_playres) {
int vidw = dim->w - (dim->ml + dim->mr);
int vidh = dim->h - (dim->mt + dim->mb);
track->PlayResX = track->PlayResY * (double)vidw / MPMAX(vidh, 1);
// ffmpeg and mpv use a default PlayResX of 384 when it is not known,
// this comes from VSFilter.
double fix_margins = track->PlayResX / (double)MP_ASS_FONT_PLAYRESX;
track->styles->MarginL = round(track->styles->MarginL * fix_margins);
track->styles->MarginR = round(track->styles->MarginR * fix_margins);
}
}
}
static bool has_overrides(char *s)
{
if (!s)
return false;
return strstr(s, "\\pos") || strstr(s, "\\move") || strstr(s, "\\clip") ||
strstr(s, "\\iclip") || strstr(s, "\\org") || strstr(s, "\\p");
}
#define END(ev) ((ev)->Start + (ev)->Duration)
static long long find_timestamp(struct sd *sd, double pts)
{
struct sd_ass_priv *priv = sd->priv;
if (pts == MP_NOPTS_VALUE)
return 0;
long long ts = llrint(pts * 1000);
if (!sd->opts->sub_fix_timing || sd->shared_opts->ass_style_override[sd->order] == 0)
return ts;
// Try to fix small gaps and overlaps.
ASS_Track *track = priv->ass_track;
int threshold = SUB_GAP_THRESHOLD * 1000;
int keep = SUB_GAP_KEEP * 1000;
// Find the "current" event.
ASS_Event *ev[2] = {0};
int n_ev = 0;
for (int n = 0; n < track->n_events; n++) {
ASS_Event *event = &track->events[n];
if (ts >= event->Start - threshold && ts <= END(event) + threshold) {
if (n_ev >= MP_ARRAY_SIZE(ev))
return ts; // multiple overlaps - give up (probably complex subs)
ev[n_ev++] = event;
}
}
if (n_ev != 2)
return ts;
// Simple/minor heuristic against destroying typesetting.
if (ev[0]->Style != ev[1]->Style || has_overrides(ev[0]->Text) ||
has_overrides(ev[1]->Text))
return ts;
// Sort by start timestamps.
if (ev[0]->Start > ev[1]->Start)
MPSWAP(ASS_Event*, ev[0], ev[1]);
// We want to fix partial overlaps only.
if (END(ev[0]) >= END(ev[1]))
return ts;
if (ev[0]->Duration < keep || ev[1]->Duration < keep)
return ts;
// Gap between the events -> move ts to show the end of the first event.
if (ts >= END(ev[0]) && ts < ev[1]->Start && END(ev[0]) < ev[1]->Start &&
END(ev[0]) + threshold >= ev[1]->Start)
return END(ev[0]) - 1;
// Overlap -> move ts to the (exclusive) end of the first event.
// Relies on the fact that the ASS_Renderer has no overlap registered, even
// if there is one. This happens to work because we never render the
// overlapped state, and libass never resolves a collision.
if (ts >= ev[1]->Start && ts <= END(ev[0]) && END(ev[0]) > ev[1]->Start &&
END(ev[0]) <= ev[1]->Start + threshold)
return END(ev[0]);
return ts;
}
#undef END
static struct sub_bitmaps *get_bitmaps(struct sd *sd, struct mp_osd_res dim,
int format, double pts)
{
struct sd_ass_priv *ctx = sd->priv;
struct mp_subtitle_opts *opts = sd->opts;
struct mp_subtitle_shared_opts *shared_opts = sd->shared_opts;
bool no_ass = !opts->ass_enabled || shared_opts->ass_style_override[sd->order] == 5;
bool converted = ctx->is_converted || no_ass;
ASS_Track *track = no_ass ? ctx->shadow_track : ctx->ass_track;
ASS_Renderer *renderer = ctx->ass_renderer;
struct sub_bitmaps *res = &(struct sub_bitmaps){0};
// Always update the osd_res
struct mp_osd_res old_osd = ctx->osd;
ctx->osd = dim;
if (pts == MP_NOPTS_VALUE || !renderer)
goto done;
// Currently no supported text sub formats support a distinction between forced
// and unforced lines, so we just assume everything's unforced and discard everything.
// If we ever see a format that makes this distinction, we can add support here.
if (opts->sub_forced_events_only)
goto done;
double scale = dim.display_par;
if (!converted && (!shared_opts->ass_style_override[sd->order] ||
opts->ass_vsfilter_aspect_compat))
{
// Let's use the original video PAR for vsfilter compatibility:
double par = ctx->video_params.p_w / (double)ctx->video_params.p_h;
if (isnormal(par))
scale *= par;
}
if (!ctx->ass_configured || !osd_res_equals(old_osd, ctx->osd)) {
configure_ass(sd, &dim, converted, track);
ctx->ass_configured = true;
}
ass_set_pixel_aspect(renderer, scale);
if (!converted && (!shared_opts->ass_style_override[sd->order] ||
opts->ass_vsfilter_blur_compat))
{
ass_set_storage_size(renderer, ctx->video_params.w, ctx->video_params.h);
} else {
ass_set_storage_size(renderer, 0, 0);
}
long long ts = find_timestamp(sd, pts);
if (no_ass)
fill_plaintext(sd, pts);
int changed;
ASS_Image *imgs = ass_render_frame(renderer, track, ts, &changed);
mp_ass_packer_pack(ctx->packer, &imgs, 1, changed, format, res);
done:
// mangle_colors() modifies the color field, so copy the thing _before_.
res = sub_bitmaps_copy(&ctx->copy_cache, res);
if (!converted && res)
mangle_colors(sd, res);
return res;
}
struct buf {
char *start;
int size;
int len;
};
static void append(struct buf *b, char c)
{
if (b->len < b->size) {
b->start[b->len] = c;
b->len++;
}
}
static void ass_to_plaintext(struct buf *b, const char *in)
{
bool in_tag = false;
const char *open_tag_pos = NULL;
bool in_drawing = false;
while (*in) {
if (in_tag) {
if (in[0] == '}') {
in += 1;
in_tag = false;
} else if (in[0] == '\\' && in[1] == 'p') {
in += 2;
// Skip text between \pN and \p0 tags. A \p without a number
// is the same as \p0, and leading 0s are also allowed.
in_drawing = false;
while (in[0] >= '0' && in[0] <= '9') {
if (in[0] != '0')
in_drawing = true;
in += 1;
}
} else {
in += 1;
}
} else {
if (in[0] == '\\' && (in[1] == 'N' || in[1] == 'n')) {
in += 2;
append(b, '\n');
} else if (in[0] == '\\' && in[1] == 'h') {
in += 2;
append(b, ' ');
} else if (in[0] == '{') {
open_tag_pos = in;
in += 1;
in_tag = true;
} else {
if (!in_drawing)
append(b, in[0]);
in += 1;
}
}
}
// A '{' without a closing '}' is always visible.
if (in_tag) {
while (*open_tag_pos)
append(b, *open_tag_pos++);
}
}
// Empty string counts as whitespace. Reads s[len-1] even if there are \0s.
static bool is_whitespace_only(char *s, int len)
{
for (int n = 0; n < len; n++) {
if (s[n] != ' ' && s[n] != '\t')
return false;
}
return true;
}
static char *get_text_buf(struct sd *sd, double pts, enum sd_text_type type)
{
struct sd_ass_priv *ctx = sd->priv;
ASS_Track *track = ctx->ass_track;
if (pts == MP_NOPTS_VALUE)
return NULL;
long long ipts = find_timestamp(sd, pts);
struct buf b = {ctx->last_text, sizeof(ctx->last_text) - 1};
for (int i = 0; i < track->n_events; ++i) {
ASS_Event *event = track->events + i;
if (ipts >= event->Start && ipts < event->Start + event->Duration) {
if (event->Text) {
int start = b.len;
if (type == SD_TEXT_TYPE_PLAIN) {
ass_to_plaintext(&b, event->Text);
} else {
char *t = event->Text;
while (*t)
append(&b, *t++);
}
if (is_whitespace_only(&b.start[start], b.len - start)) {
b.len = start;
} else {
append(&b, '\n');
}
}
}
}
b.start[b.len] = '\0';
if (b.len > 0 && b.start[b.len - 1] == '\n')
b.start[b.len - 1] = '\0';
return ctx->last_text;
}
static char *get_text(struct sd *sd, double pts, enum sd_text_type type)
{
return talloc_strdup(NULL, get_text_buf(sd, pts, type));
}
static struct sd_times get_times(struct sd *sd, double pts)
{
struct sd_ass_priv *ctx = sd->priv;
ASS_Track *track = ctx->ass_track;
struct sd_times res = { .start = MP_NOPTS_VALUE, .end = MP_NOPTS_VALUE };
if (pts == MP_NOPTS_VALUE)
return res;
long long ipts = find_timestamp(sd, pts);
for (int i = 0; i < track->n_events; ++i) {
ASS_Event *event = track->events + i;
if (ipts >= event->Start && ipts < event->Start + event->Duration) {
double start = event->Start / 1000.0;
double end = event->Duration == UNKNOWN_DURATION ?
MP_NOPTS_VALUE : (event->Start + event->Duration) / 1000.0;
if (res.start == MP_NOPTS_VALUE || res.start > start)
res.start = start;
if (res.end == MP_NOPTS_VALUE || res.end < end)
res.end = end;
}
}
return res;
}
static void fill_plaintext(struct sd *sd, double pts)
{
struct sd_ass_priv *ctx = sd->priv;
ASS_Track *track = ctx->shadow_track;
ass_flush_events(track);
char *text = get_text_buf(sd, pts, SD_TEXT_TYPE_PLAIN);
if (!text)
return;
bstr dst = {0};
while (*text) {
if (*text == '{')
bstr_xappend(NULL, &dst, bstr0("\\"));
bstr_xappend(NULL, &dst, (bstr){text, 1});
// Break ASS escapes with U+2060 WORD JOINER
if (*text == '\\')
mp_append_utf8_bstr(NULL, &dst, 0x2060);
text++;
}
if (!dst.start)
return;
int n = ass_alloc_event(track);
ASS_Event *event = track->events + n;
event->Start = 0;
event->Duration = INT_MAX;
event->Style = track->default_style;
event->Text = strdup(dst.start);
talloc_free(dst.start);
}
static void reset(struct sd *sd)
{
struct sd_ass_priv *ctx = sd->priv;
if (sd->opts->sub_clear_on_seek || ctx->clear_once) {
ass_flush_events(ctx->ass_track);
ctx->num_seen_packets = 0;
sd->preload_ok = false;
ctx->clear_once = false;
}
if (ctx->converter)
lavc_conv_reset(ctx->converter);
}
static void uninit(struct sd *sd)
{
struct sd_ass_priv *ctx = sd->priv;
filters_destroy(sd);
if (ctx->converter)
lavc_conv_uninit(ctx->converter);
assobjects_destroy(sd);
talloc_free(ctx->copy_cache);
}
static int control(struct sd *sd, enum sd_ctrl cmd, void *arg)
{
struct sd_ass_priv *ctx = sd->priv;
switch (cmd) {
case SD_CTRL_SUB_STEP: {
double *a = arg;
long long ts = llrint(a[0] * 1000.0);
long long res = ass_step_sub(ctx->ass_track, ts, a[1]);
if (!res)
return false;
// Try to account for overlapping durations
a[0] += res / 1000.0 + SUB_SEEK_OFFSET;
return true;
}
case SD_CTRL_SET_VIDEO_PARAMS:
ctx->video_params = *(struct mp_image_params *)arg;
return CONTROL_OK;
case SD_CTRL_UPDATE_OPTS: {
int flags = (uintptr_t)arg;
if (flags & UPDATE_SUB_FILT) {
filters_destroy(sd);
filters_init(sd);
ctx->clear_once = true; // allow reloading on seeks
reset(sd);
}
if (flags & UPDATE_SUB_HARD) {
// ass_track will be recreated, so clear duplicate cache
ctx->clear_once = true;
reset(sd);
assobjects_destroy(sd);
assobjects_init(sd);
}
ctx->ass_configured = false; // ass always needs to be reconfigured
return CONTROL_OK;
}
default:
return CONTROL_UNKNOWN;
}
}
const struct sd_functions sd_ass = {
.name = "ass",
.accept_packets_in_advance = true,
.init = init,
.decode = decode,
.get_bitmaps = get_bitmaps,
.get_text = get_text,
.get_times = get_times,
.control = control,
.reset = reset,
.select = enable_output,
.uninit = uninit,
};
// Disgusting hack for (xy-)vsfilter color compatibility.
static void mangle_colors(struct sd *sd, struct sub_bitmaps *parts)
{
struct mp_subtitle_opts *opts = sd->opts;
struct sd_ass_priv *ctx = sd->priv;
enum pl_color_system csp = 0;
enum pl_color_levels levels = 0;
if (opts->ass_vsfilter_color_compat == 0) // "no"
return;
bool force_601 = opts->ass_vsfilter_color_compat == 3;
ASS_Track *track = ctx->ass_track;
static const int ass_csp[] = {
[YCBCR_BT601_TV] = PL_COLOR_SYSTEM_BT_601,
[YCBCR_BT601_PC] = PL_COLOR_SYSTEM_BT_601,
[YCBCR_BT709_TV] = PL_COLOR_SYSTEM_BT_709,
[YCBCR_BT709_PC] = PL_COLOR_SYSTEM_BT_709,
[YCBCR_SMPTE240M_TV] = PL_COLOR_SYSTEM_SMPTE_240M,
[YCBCR_SMPTE240M_PC] = PL_COLOR_SYSTEM_SMPTE_240M,
};
static const int ass_levels[] = {
[YCBCR_BT601_TV] = PL_COLOR_LEVELS_LIMITED,
[YCBCR_BT601_PC] = PL_COLOR_LEVELS_FULL,
[YCBCR_BT709_TV] = PL_COLOR_LEVELS_LIMITED,
[YCBCR_BT709_PC] = PL_COLOR_LEVELS_FULL,
[YCBCR_SMPTE240M_TV] = PL_COLOR_LEVELS_LIMITED,
[YCBCR_SMPTE240M_PC] = PL_COLOR_LEVELS_FULL,
};
int trackcsp = track->YCbCrMatrix;
if (force_601)
trackcsp = YCBCR_BT601_TV;
// NONE is a bit random, but the intention is: don't modify colors.
if (trackcsp == YCBCR_NONE)
return;
if (trackcsp < sizeof(ass_csp) / sizeof(ass_csp[0]))
csp = ass_csp[trackcsp];
if (trackcsp < sizeof(ass_levels) / sizeof(ass_levels[0]))
levels = ass_levels[trackcsp];
if (trackcsp == YCBCR_DEFAULT) {
csp = PL_COLOR_SYSTEM_BT_601;
levels = PL_COLOR_LEVELS_LIMITED;
}
// Unknown colorspace (either YCBCR_UNKNOWN, or a valid value unknown to us)
if (!csp || !levels)
return;
struct mp_image_params params = ctx->video_params;
if (force_601) {
params.repr = (struct pl_color_repr){
.sys = PL_COLOR_SYSTEM_BT_709,
.levels = PL_COLOR_LEVELS_LIMITED,
};
}
if ((csp == params.repr.sys && levels == params.repr.levels) ||
params.repr.sys == PL_COLOR_SYSTEM_RGB) // Even VSFilter doesn't mangle on RGB video
return;
bool basic_conv = params.repr.sys == PL_COLOR_SYSTEM_BT_709 &&
params.repr.levels == PL_COLOR_LEVELS_LIMITED &&
csp == PL_COLOR_SYSTEM_BT_601 &&
levels == PL_COLOR_LEVELS_LIMITED;
// With "basic", only do as much as needed for basic compatibility.
if (opts->ass_vsfilter_color_compat == 1 && !basic_conv)
return;
if (params.repr.sys != ctx->last_params.repr.sys ||
params.repr.levels != ctx->last_params.repr.levels)
{
int msgl = basic_conv ? MSGL_V : MSGL_WARN;
ctx->last_params = params;
MP_MSG(sd, msgl, "mangling colors like vsfilter: "
"RGB -> %s %s -> %s %s -> RGB\n",
m_opt_choice_str(pl_csp_names, csp),
m_opt_choice_str(pl_csp_levels_names, levels),
m_opt_choice_str(pl_csp_names, params.repr.sys),
m_opt_choice_str(pl_csp_names, params.repr.levels));
}
// Conversion that VSFilter would use
struct mp_csp_params vs_params = MP_CSP_PARAMS_DEFAULTS;
vs_params.repr.sys = csp;
vs_params.repr.levels = levels;
struct pl_transform3x3 vs_yuv2rgb;
mp_get_csp_matrix(&vs_params, &vs_yuv2rgb);
pl_transform3x3_invert(&vs_yuv2rgb);
// Proper conversion to RGB
struct mp_csp_params rgb_params = MP_CSP_PARAMS_DEFAULTS;
rgb_params.repr = params.repr;
rgb_params.color = params.color;
struct pl_transform3x3 vs2rgb;
mp_get_csp_matrix(&rgb_params, &vs2rgb);
for (int n = 0; n < parts->num_parts; n++) {
struct sub_bitmap *sb = &parts->parts[n];
uint32_t color = sb->libass.color;
int r = (color >> 24u) & 0xff;
int g = (color >> 16u) & 0xff;
int b = (color >> 8u) & 0xff;
int a = 0xff - (color & 0xff);
int rgb[3] = {r, g, b}, yuv[3];
mp_map_fixp_color(&vs_yuv2rgb, 8, rgb, 8, yuv);
mp_map_fixp_color(&vs2rgb, 8, yuv, 8, rgb);
sb->libass.color = MP_ASS_RGBA(rgb[0], rgb[1], rgb[2], a);
}
}
int sd_ass_fmt_offset(const char *evt_fmt)
{
// "Text" is always last (as it's arbitrary content in buf), e.g. format:
// "Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text"
int n = 0;
while (evt_fmt && (evt_fmt = strchr(evt_fmt, ',')))
evt_fmt++, n++;
return n-1; // buffer is without the format's Start/End, with ReadOrder
}
bstr sd_ass_pkt_text(struct sd_filter *ft, struct demux_packet *pkt, int offset)
{
// e.g. pkt->buffer ("4" is ReadOrder): "4,0,Default,,0,0,0,,fifth line"
bstr txt = {(char *)pkt->buffer, pkt->len}, t0 = txt;
while (offset-- > 0) {
int n = bstrchr(txt, ',');
if (n < 0) { // shouldn't happen
MP_WARN(ft, "Malformed event '%.*s'\n", BSTR_P(t0));
return (bstr){NULL, 0};
}
txt = bstr_cut(txt, n+1);
}
return txt;
}
bstr sd_ass_to_plaintext(char *out, size_t out_siz, const char *in)
{
struct buf b = {out, out_siz, 0};
ass_to_plaintext(&b, in);
if (b.len < out_siz)
out[b.len] = 0;
return (bstr){out, b.len};
}