mpv/sub/dec_sub.c

631 lines
19 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 "misc/charset_conv.h"
#include "osdep/threads.h"
extern const struct sd_functions sd_ass;
extern const struct sd_functions sd_lavc;
extern const struct sd_functions sd_movtext;
extern const struct sd_functions sd_srt;
extern const struct sd_functions sd_microdvd;
extern const struct sd_functions sd_lavf_srt;
extern const struct sd_functions sd_lavc_conv;
static const struct sd_functions *const sd_list[] = {
#if HAVE_LIBASS
&sd_ass,
#endif
&sd_lavc,
&sd_movtext,
&sd_srt,
&sd_lavf_srt,
&sd_microdvd,
&sd_lavc_conv,
NULL
};
#define MAX_NUM_SD 3
struct dec_sub {
pthread_mutex_t lock;
struct mp_log *log;
struct MPOpts *opts;
struct sd init_sd;
double video_fps;
const char *charset;
struct sd *sd[MAX_NUM_SD];
int num_sd;
};
struct packet_list {
struct demux_packet **packets;
int num_packets;
};
void sub_lock(struct dec_sub *sub)
{
pthread_mutex_lock(&sub->lock);
}
void sub_unlock(struct dec_sub *sub)
{
pthread_mutex_unlock(&sub->lock);
}
// 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 dec_sub *sub = talloc_zero(NULL, struct dec_sub);
sub->log = mp_log_new(sub, global->log, "sub");
sub->opts = global->opts;
mpthread_mutex_init_recursive(&sub->lock);
return sub;
}
static void sub_uninit(struct dec_sub *sub)
{
sub_reset(sub);
for (int n = 0; n < sub->num_sd; n++) {
if (sub->sd[n]->driver->uninit)
sub->sd[n]->driver->uninit(sub->sd[n]);
talloc_free(sub->sd[n]);
}
sub->num_sd = 0;
}
void sub_destroy(struct dec_sub *sub)
{
if (!sub)
return;
sub_uninit(sub);
pthread_mutex_destroy(&sub->lock);
talloc_free(sub);
}
bool sub_is_initialized(struct dec_sub *sub)
{
pthread_mutex_lock(&sub->lock);
bool r = !!sub->num_sd;
pthread_mutex_unlock(&sub->lock);
return r;
}
static struct sd *sub_get_last_sd(struct dec_sub *sub)
{
return sub->num_sd ? sub->sd[sub->num_sd - 1] : NULL;
}
void sub_set_video_res(struct dec_sub *sub, int w, int h)
{
pthread_mutex_lock(&sub->lock);
sub->init_sd.sub_video_w = w;
sub->init_sd.sub_video_h = h;
pthread_mutex_unlock(&sub->lock);
}
void sub_set_video_fps(struct dec_sub *sub, double fps)
{
pthread_mutex_lock(&sub->lock);
sub->video_fps = fps;
pthread_mutex_unlock(&sub->lock);
}
void sub_set_extradata(struct dec_sub *sub, void *data, int data_len)
{
pthread_mutex_lock(&sub->lock);
sub->init_sd.extradata = data_len ? talloc_memdup(sub, data, data_len) : NULL;
sub->init_sd.extradata_len = data_len;
pthread_mutex_unlock(&sub->lock);
}
void sub_set_ass_renderer(struct dec_sub *sub, struct ass_library *ass_library,
struct ass_renderer *ass_renderer,
pthread_mutex_t *ass_lock)
{
pthread_mutex_lock(&sub->lock);
sub->init_sd.ass_library = ass_library;
sub->init_sd.ass_renderer = ass_renderer;
sub->init_sd.ass_lock = ass_lock;
pthread_mutex_unlock(&sub->lock);
}
static void print_chain(struct dec_sub *sub)
{
MP_VERBOSE(sub, "Subtitle filter chain: ");
for (int n = 0; n < sub->num_sd; n++) {
struct sd *sd = sub->sd[n];
MP_VERBOSE(sub, "%s%s (%s)", n > 0 ? " -> " : "",
sd->driver->name, sd->codec);
}
MP_VERBOSE(sub, "\n");
}
static int sub_init_decoder(struct dec_sub *sub, struct sd *sd)
{
sd->driver = NULL;
for (int n = 0; sd_list[n]; n++) {
if (sd_list[n]->supports_format(sd->codec)) {
sd->driver = sd_list[n];
break;
}
}
if (!sd->driver)
return -1;
sd->log = mp_log_new(sd, sub->log, sd->driver->name);
if (sd->driver->init(sd) < 0)
return -1;
return 0;
}
void sub_init_from_sh(struct dec_sub *sub, struct sh_stream *sh)
{
assert(!sub->num_sd);
assert(sh && sh->sub);
pthread_mutex_lock(&sub->lock);
if (sh->extradata && !sub->init_sd.extradata)
sub_set_extradata(sub, sh->extradata, sh->extradata_size);
struct sd init_sd = sub->init_sd;
init_sd.codec = sh->codec;
while (sub->num_sd < MAX_NUM_SD) {
struct sd *sd = talloc(NULL, struct sd);
*sd = init_sd;
sd->opts = sub->opts;
if (sub_init_decoder(sub, sd) < 0) {
talloc_free(sd);
break;
}
sub->sd[sub->num_sd] = sd;
sub->num_sd++;
// Try adding new converters until a decoder is reached
if (sd->driver->get_bitmaps || sd->driver->get_text) {
print_chain(sub);
pthread_mutex_unlock(&sub->lock);
return;
}
init_sd = (struct sd) {
.codec = sd->output_codec,
.converted_from = sd->codec,
.extradata = sd->output_extradata,
.extradata_len = sd->output_extradata_len,
.ass_library = sub->init_sd.ass_library,
.ass_renderer = sub->init_sd.ass_renderer,
.ass_lock = sub->init_sd.ass_lock,
};
}
sub_uninit(sub);
MP_ERR(sub, "Could not find subtitle decoder for format '%s'.\n",
sh->codec ? sh->codec : "<unknown>");
pthread_mutex_unlock(&sub->lock);
}
static struct demux_packet *get_decoded_packet(struct sd *sd)
{
return sd->driver->get_converted ? sd->driver->get_converted(sd) : NULL;
}
static void decode_chain(struct sd **sd, int num_sd, struct demux_packet *packet)
{
if (num_sd == 0)
return;
struct sd *dec = sd[0];
dec->driver->decode(dec, packet);
if (num_sd > 1) {
while (1) {
struct demux_packet *next = get_decoded_packet(dec);
if (!next)
break;
decode_chain(sd + 1, num_sd - 1, next);
}
}
}
static struct demux_packet *recode_packet(struct mp_log *log,
struct demux_packet *in,
const char *charset)
{
struct demux_packet *pkt = NULL;
bstr in_buf = {in->buffer, in->len};
bstr conv = mp_iconv_to_utf8(log, in_buf, charset, MP_ICONV_VERBOSE);
if (conv.start && conv.start != in_buf.start) {
pkt = talloc_ptrtype(NULL, pkt);
talloc_steal(pkt, conv.start);
*pkt = (struct demux_packet) {
.buffer = conv.start,
.len = conv.len,
.pts = in->pts,
.duration = in->duration,
.avpacket = in->avpacket, // questionable, but gives us sidedata
};
}
return pkt;
}
static void decode_chain_recode(struct dec_sub *sub, struct sd **sd, int num_sd,
struct demux_packet *packet)
{
if (num_sd > 0) {
struct demux_packet *recoded = NULL;
if (sub->charset)
recoded = recode_packet(sub->log, packet, sub->charset);
decode_chain(sd, num_sd, recoded ? recoded : packet);
talloc_free(recoded);
}
}
void sub_decode(struct dec_sub *sub, struct demux_packet *packet)
{
pthread_mutex_lock(&sub->lock);
decode_chain_recode(sub, sub->sd, sub->num_sd, packet);
pthread_mutex_unlock(&sub->lock);
}
static const char *guess_sub_cp(struct mp_log *log, struct packet_list *subs,
const char *usercp)
{
if (!mp_charset_requires_guess(usercp))
return usercp;
// Concat all subs into a buffer. We can't probably do much better without
// having the original data (which we don't, not anymore).
int max_size = 2 * 1024 * 1024;
const char *sep = "\n\n"; // In utf-16: U+0A0A GURMUKHI LETTER UU
int sep_len = strlen(sep);
int num_pkt = 0;
int size = 0;
for (int n = 0; n < subs->num_packets; n++) {
struct demux_packet *pkt = subs->packets[n];
if (size + pkt->len > max_size)
break;
size += pkt->len + sep_len;
num_pkt++;
}
bstr text = {talloc_size(NULL, size), 0};
for (int n = 0; n < num_pkt; n++) {
struct demux_packet *pkt = subs->packets[n];
memcpy(text.start + text.len, pkt->buffer, pkt->len);
memcpy(text.start + text.len + pkt->len, sep, sep_len);
text.len += pkt->len + sep_len;
}
const char *guess = mp_charset_guess(log, text, usercp, 0);
talloc_free(text.start);
return guess;
}
static void multiply_timings(struct packet_list *subs, double factor)
{
for (int n = 0; n < subs->num_packets; n++) {
struct demux_packet *pkt = subs->packets[n];
if (pkt->pts != MP_NOPTS_VALUE)
pkt->pts *= factor;
if (pkt->duration > 0)
pkt->duration *= factor;
}
}
#define MS_TS(f_ts) ((long long)((f_ts) * 1000 + 0.5))
// Remove overlaps and fill gaps between adjacent subtitle packets. This is done
// by adjusting the duration of the earlier packet. If the gaps or overlap are
// larger than the threshold, or if the durations are close to the threshold,
// don't change the events.
// The algorithm is maximally naive and doesn't work if there are multiple
// overlapping lines. (It's not worth the trouble.)
static void fix_overlaps_and_gaps(struct packet_list *subs)
{
double threshold = 0.2; // up to 200 ms overlaps or gaps are removed
double keep = threshold * 2;// don't change timings if durations are smaller
for (int i = 0; i < subs->num_packets - 1; i++) {
struct demux_packet *cur = subs->packets[i];
struct demux_packet *next = subs->packets[i + 1];
if (cur->pts != MP_NOPTS_VALUE && cur->duration > 0 &&
next->pts != MP_NOPTS_VALUE && next->duration > 0)
{
double end = cur->pts + cur->duration;
if (fabs(next->pts - end) <= threshold && cur->duration >= keep &&
next->duration >= keep)
{
// Conceptually: cur->duration = next->pts - cur->pts;
// But make sure the rounding and conversion to integers in
// sd_ass.c can't produce overlaps.
cur->duration = (MS_TS(next->pts) - MS_TS(cur->pts)) / 1000.0;
}
}
}
}
static void add_sub_list(struct dec_sub *sub, int at, struct packet_list *subs)
{
struct sd *sd = sub_get_last_sd(sub);
assert(sd);
sd->no_remove_duplicates = true;
for (int n = 0; n < subs->num_packets; n++)
decode_chain_recode(sub, sub->sd + at, sub->num_sd - at, subs->packets[n]);
// Hack for broken FFmpeg packet format: make sd_ass keep the subtitle
// events on reset(), even if broken FFmpeg ASS packets were received
// (from sd_lavc_conv.c). Normally, these events are removed on seek/reset,
// but this is obviously unwanted in this case.
if (sd->driver->fix_events)
sd->driver->fix_events(sd);
sd->no_remove_duplicates = false;
}
static void add_packet(struct packet_list *subs, struct demux_packet *pkt)
{
pkt = demux_copy_packet(pkt);
if (pkt) {
talloc_steal(subs, pkt);
MP_TARRAY_APPEND(subs, subs->packets, subs->num_packets, pkt);
}
}
// 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, struct sh_stream *sh)
{
assert(sh && sh->sub);
struct MPOpts *opts = sub->opts;
pthread_mutex_lock(&sub->lock);
if (!sub_accept_packets_in_advance(sub) || sub->num_sd < 1) {
pthread_mutex_unlock(&sub->lock);
return false;
}
struct packet_list *subs = talloc_zero(NULL, struct packet_list);
// In some cases, we want to put the packets through a decoder first.
// Preprocess until sub->sd[preprocess].
int preprocess = 0;
// movtext is currently the only subtitle format that has text output,
// but binary input. Do charset conversion after converting to text.
if (sub->sd[0]->driver == &sd_movtext)
preprocess = 1;
// Broken Libav libavformat srt packet format (fix timestamps first).
if (sub->sd[0]->driver == &sd_lavf_srt)
preprocess = 1;
for (;;) {
struct demux_packet *pkt = demux_read_packet(sh);
if (!pkt)
break;
if (preprocess) {
decode_chain(sub->sd, preprocess, pkt);
talloc_free(pkt);
while (1) {
pkt = get_decoded_packet(sub->sd[preprocess - 1]);
if (!pkt)
break;
add_packet(subs, pkt);
}
} else {
add_packet(subs, pkt);
talloc_free(pkt);
}
}
if (opts->sub_cp && !sh->sub->is_utf8)
sub->charset = guess_sub_cp(sub->log, subs, opts->sub_cp);
if (sub->charset && sub->charset[0] && !mp_charset_is_utf8(sub->charset))
MP_INFO(sub, "Using subtitle charset: %s\n", sub->charset);
double sub_speed = 1.0;
if (sub->video_fps && sh->sub->frame_based > 0) {
MP_VERBOSE(sub, "Frame based format, dummy FPS: %f, video FPS: %f\n",
sh->sub->frame_based, sub->video_fps);
sub_speed *= sh->sub->frame_based / sub->video_fps;
}
if (opts->sub_fps && sub->video_fps)
sub_speed *= opts->sub_fps / sub->video_fps;
sub_speed *= opts->sub_speed;
if (sub_speed != 1.0)
multiply_timings(subs, sub_speed);
if (opts->sub_fix_timing)
fix_overlaps_and_gaps(subs);
if (sh->codec && strcmp(sh->codec, "microdvd") == 0) {
// The last subtitle event in MicroDVD subs can have duration unset,
// which means show the subtitle until end of video.
// See FFmpeg FATE MicroDVD_capability_tester.sub
if (subs->num_packets) {
struct demux_packet *last = subs->packets[subs->num_packets - 1];
if (last->duration <= 0)
last->duration = 10; // arbitrary
}
}
add_sub_list(sub, preprocess, subs);
pthread_mutex_unlock(&sub->lock);
talloc_free(subs);
return true;
}
bool sub_accept_packets_in_advance(struct dec_sub *sub)
{
pthread_mutex_lock(&sub->lock);
// Converters are assumed to always accept packets in advance
struct sd *sd = sub_get_last_sd(sub);
bool r = sd && sd->driver->accept_packets_in_advance;
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;
struct sd *sd = sub_get_last_sd(sub);
*res = (struct sub_bitmaps) {0};
if (sd && opts->sub_visibility) {
if (sd->driver->get_bitmaps)
sd->driver->get_bitmaps(sd, dim, pts, res);
}
}
bool sub_has_get_text(struct dec_sub *sub)
{
pthread_mutex_lock(&sub->lock);
struct sd *sd = sub_get_last_sd(sub);
bool r = sd && sd->driver->get_text;
pthread_mutex_unlock(&sub->lock);
return r;
}
// 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;
struct sd *sd = sub_get_last_sd(sub);
char *text = NULL;
if (sd && opts->sub_visibility) {
if (sd->driver->get_text)
text = sd->driver->get_text(sd, pts);
}
pthread_mutex_unlock(&sub->lock);
return text;
}
void sub_reset(struct dec_sub *sub)
{
pthread_mutex_lock(&sub->lock);
for (int n = 0; n < sub->num_sd; n++) {
if (sub->sd[n]->driver->reset)
sub->sd[n]->driver->reset(sub->sd[n]);
}
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);
for (int n = 0; n < sub->num_sd; n++) {
if (sub->sd[n]->driver->control) {
r = sub->sd[n]->driver->control(sub->sd[n], cmd, arg);
if (r != CONTROL_UNKNOWN)
break;
}
}
pthread_mutex_unlock(&sub->lock);
return r;
}
#define MAX_PACKETS 10
#define MAX_BYTES 10000
struct sd_conv_buffer {
struct demux_packet pkt[MAX_PACKETS];
int num_pkt;
int read_pkt;
char buffer[MAX_BYTES];
int cur_buffer;
};
void sd_conv_add_packet(struct sd *sd, void *data, int data_len, double pts,
double duration)
{
if (!sd->sd_conv_buffer)
sd->sd_conv_buffer = talloc_zero(sd, struct sd_conv_buffer);
struct sd_conv_buffer *buf = sd->sd_conv_buffer;
if (buf->num_pkt >= MAX_PACKETS || buf->cur_buffer + data_len + 1 > MAX_BYTES)
goto out_of_space;
if (buf->read_pkt == buf->num_pkt)
sd_conv_def_reset(sd);
assert(buf->read_pkt == 0); // no mixing of reading/adding allowed
struct demux_packet *pkt = &buf->pkt[buf->num_pkt++];
*pkt = (struct demux_packet) {
.buffer = &buf->buffer[buf->cur_buffer],
.len = data_len,
.pts = pts,
.duration = duration,
};
memcpy(pkt->buffer, data, data_len);
pkt->buffer[data_len] = 0;
buf->cur_buffer += data_len + 1;
return;
out_of_space:
MP_ERR(sd, "Subtitle too big.\n");
}
struct demux_packet *sd_conv_def_get_converted(struct sd *sd)
{
struct sd_conv_buffer *buf = sd->sd_conv_buffer;
if (buf && buf->read_pkt < buf->num_pkt)
return &buf->pkt[buf->read_pkt++];
return NULL;
}
void sd_conv_def_reset(struct sd *sd)
{
struct sd_conv_buffer *buf = sd->sd_conv_buffer;
if (buf) {
buf->read_pkt = buf->num_pkt = 0;
buf->cur_buffer = 0;
}
}