mpv/sub/dec_sub.c

233 lines
6.6 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 General Public License as published by
* the Free Software Foundation; either version 2 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
#include <math.h>
#include <assert.h>
#include <pthread.h>
#include "config.h"
#include "demux/demux.h"
#include "sd.h"
#include "dec_sub.h"
#include "options/options.h"
#include "common/global.h"
#include "common/msg.h"
#include "osdep/threads.h"
extern const struct sd_functions sd_ass;
extern const struct sd_functions sd_lavc;
static const struct sd_functions *const sd_list[] = {
&sd_lavc,
#if HAVE_LIBASS
&sd_ass,
#endif
NULL
};
struct dec_sub {
pthread_mutex_t lock;
struct mp_log *log;
struct MPOpts *opts;
struct sh_stream *sh;
double last_pkt_pts;
struct sd *sd;
};
void sub_lock(struct dec_sub *sub)
{
pthread_mutex_lock(&sub->lock);
}
void sub_unlock(struct dec_sub *sub)
{
pthread_mutex_unlock(&sub->lock);
}
void sub_destroy(struct dec_sub *sub)
{
if (!sub)
return;
sub_reset(sub);
sub->sd->driver->uninit(sub->sd);
talloc_free(sub->sd);
pthread_mutex_destroy(&sub->lock);
talloc_free(sub);
}
// Thread-safety of the returned object: all functions are thread-safe,
// except sub_get_bitmaps() and sub_get_text(). Decoder backends (sd_*)
// do not need to acquire locks.
struct dec_sub *sub_create(struct mpv_global *global, struct demuxer *demuxer,
struct sh_stream *sh)
{
assert(demuxer && sh && sh->sub);
struct mp_log *log = mp_log_new(NULL, global->log, "sub");
for (int n = 0; sd_list[n]; n++) {
const struct sd_functions *driver = sd_list[n];
struct dec_sub *sub = talloc_zero(NULL, struct dec_sub);
sub->log = talloc_steal(sub, log),
sub->opts = global->opts;
sub->sh = sh;
sub->last_pkt_pts = MP_NOPTS_VALUE;
mpthread_mutex_init_recursive(&sub->lock);
sub->sd = talloc(NULL, struct sd);
*sub->sd = (struct sd){
.global = global,
.log = mp_log_new(sub->sd, sub->log, driver->name),
.opts = sub->opts,
.driver = driver,
.demuxer = demuxer,
.sh = sh,
};
if (sh->codec && sub->sd->driver->init(sub->sd) >= 0)
return sub;
ta_set_parent(log, NULL);
talloc_free(sub->sd);
talloc_free(sub);
}
mp_err(log, "Could not find subtitle decoder for format '%s'.\n",
sh->codec ? sh->codec : "<unknown>");
talloc_free(log);
return NULL;
}
// Read all packets from the demuxer and decode/add them. Returns false if
// there are circumstances which makes this not possible.
bool sub_read_all_packets(struct dec_sub *sub)
{
pthread_mutex_lock(&sub->lock);
if (!sub->sd->driver->accept_packets_in_advance) {
pthread_mutex_unlock(&sub->lock);
return false;
}
for (;;) {
struct demux_packet *pkt = demux_read_packet(sub->sh);
if (!pkt)
break;
sub->sd->driver->decode(sub->sd, pkt);
talloc_free(pkt);
}
pthread_mutex_unlock(&sub->lock);
return true;
}
// Read packets from the demuxer stream passed to sub_create(). Return true if
// enough packets were read, false if the player should wait until the demuxer
// signals new packets available (and then should retry).
bool sub_read_packets(struct dec_sub *sub, double video_pts)
{
bool r = true;
pthread_mutex_lock(&sub->lock);
while (1) {
bool read_more = true;
if (sub->sd->driver->accepts_packet)
read_more = sub->sd->driver->accepts_packet(sub->sd);
if (!read_more)
break;
struct demux_packet *pkt;
int st = demux_read_packet_async(sub->sh, &pkt);
// Note: "wait" (st==0) happens with non-interleaved streams only, and
// then we should stop the playloop until a new enough packet has been
// seen (or the subtitle decoder's queue is full). This does not happen
// for interleaved subtitle streams, which never return "wait" when
// reading.
if (st <= 0) {
r = st < 0 || (sub->last_pkt_pts != MP_NOPTS_VALUE &&
sub->last_pkt_pts > video_pts);
break;
}
sub->sd->driver->decode(sub->sd, pkt);
sub->last_pkt_pts = pkt->pts;
talloc_free(pkt);
}
pthread_mutex_unlock(&sub->lock);
return r;
}
// You must call sub_lock/sub_unlock if more than 1 thread access sub.
// The issue is that *res will contain decoder allocated data, which might
// be deallocated on the next decoder access.
void sub_get_bitmaps(struct dec_sub *sub, struct mp_osd_res dim, double pts,
struct sub_bitmaps *res)
{
struct MPOpts *opts = sub->opts;
*res = (struct sub_bitmaps) {0};
if (opts->sub_visibility && sub->sd->driver->get_bitmaps)
sub->sd->driver->get_bitmaps(sub->sd, dim, pts, res);
}
// See sub_get_bitmaps() for locking requirements.
// It can be called unlocked too, but then only 1 thread must call this function
// at a time (unless exclusive access is guaranteed).
char *sub_get_text(struct dec_sub *sub, double pts)
{
pthread_mutex_lock(&sub->lock);
struct MPOpts *opts = sub->opts;
char *text = NULL;
if (opts->sub_visibility && sub->sd->driver->get_text)
text = sub->sd->driver->get_text(sub->sd, pts);
pthread_mutex_unlock(&sub->lock);
return text;
}
void sub_reset(struct dec_sub *sub)
{
pthread_mutex_lock(&sub->lock);
if (sub->sd->driver->reset)
sub->sd->driver->reset(sub->sd);
sub->last_pkt_pts = MP_NOPTS_VALUE;
pthread_mutex_unlock(&sub->lock);
}
void sub_select(struct dec_sub *sub, bool selected)
{
pthread_mutex_lock(&sub->lock);
if (sub->sd->driver->select)
sub->sd->driver->select(sub->sd, selected);
pthread_mutex_unlock(&sub->lock);
}
int sub_control(struct dec_sub *sub, enum sd_ctrl cmd, void *arg)
{
int r = CONTROL_UNKNOWN;
pthread_mutex_lock(&sub->lock);
if (sub->sd->driver->control)
r = sub->sd->driver->control(sub->sd, cmd, arg);
pthread_mutex_unlock(&sub->lock);
return r;
}