mpv/common/codecs.c

169 lines
6.4 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 <assert.h>
#include "talloc.h"
#include "misc/bstr.h"
#include "common/msg.h"
#include "codecs.h"
void mp_add_decoder(struct mp_decoder_list *list, const char *family,
const char *codec, const char *decoder, const char *desc)
{
struct mp_decoder_entry entry = {
.family = talloc_strdup(list, family),
.codec = talloc_strdup(list, codec),
.decoder = talloc_strdup(list, decoder),
.desc = talloc_strdup(list, desc),
};
MP_TARRAY_APPEND(list, list->entries, list->num_entries, entry);
}
static void mp_add_decoder_entry(struct mp_decoder_list *list,
struct mp_decoder_entry *entry)
{
mp_add_decoder(list, entry->family, entry->codec, entry->decoder,
entry->desc);
}
static struct mp_decoder_entry *find_decoder(struct mp_decoder_list *list,
bstr family, bstr decoder)
{
for (int n = 0; n < list->num_entries; n++) {
struct mp_decoder_entry *cur = &list->entries[n];
if (bstr_equals0(decoder, cur->decoder) &&
bstr_equals0(family, cur->family))
return cur;
}
return NULL;
}
// Add entry, but only if it's not yet on the list, and if the codec matches.
// If codec == NULL, don't compare codecs.
static void add_new(struct mp_decoder_list *to, struct mp_decoder_entry *entry,
const char *codec)
{
if (!entry || (codec && strcmp(entry->codec, codec) != 0))
return;
if (!find_decoder(to, bstr0(entry->family), bstr0(entry->decoder)))
mp_add_decoder_entry(to, entry);
}
// Select a decoder from the given list for the given codec. The selection
// can be influenced by the selection string, which can specify a priority
// list of preferred decoders.
// This returns a list of decoders to try, with the preferred decoders first.
// The selection string corresponds to --vd/--ad directly, and has the
// following syntax:
// selection = [<entry> ("," <entry>)*]
// entry = <family> ":" <decoder> // prefer decoder
// entry = <family> ":*" // prefer all decoders
// entry = "+" <family> ":" <decoder> // force a decoder
// entry = "-" <family> ":" <decoder> // exclude a decoder
// entry = "-" // don't add fallback decoders
// Forcing a decoder means it's added even if the codec mismatches.
struct mp_decoder_list *mp_select_decoders(struct mp_decoder_list *all,
const char *codec,
const char *selection)
{
struct mp_decoder_list *list = talloc_zero(NULL, struct mp_decoder_list);
struct mp_decoder_list *remove = talloc_zero(NULL, struct mp_decoder_list);
if (!codec)
codec = "unknown";
bool stop = false;
bstr sel = bstr0(selection);
while (sel.len) {
bstr entry;
bstr_split_tok(sel, ",", &entry, &sel);
if (bstr_equals0(entry, "-")) {
stop = true;
break;
}
bool force = bstr_eatstart0(&entry, "+");
bool exclude = !force && bstr_eatstart0(&entry, "-");
struct mp_decoder_list *dest = exclude ? remove : list;
bstr family, decoder;
if (!bstr_split_tok(entry, ":", &family, &decoder)) {
family = entry;
decoder = bstr0("*");
}
if (bstr_equals0(decoder, "*")) {
for (int n = 0; n < all->num_entries; n++) {
struct mp_decoder_entry *cur = &all->entries[n];
if (bstr_equals0(family, cur->family))
add_new(dest, cur, codec);
}
} else {
add_new(dest, find_decoder(all, family, decoder),
force ? NULL : codec);
}
}
if (!stop) {
// Add the remaining codecs which haven't been added yet
for (int n = 0; n < all->num_entries; n++)
add_new(list, &all->entries[n], codec);
}
for (int n = 0; n < remove->num_entries; n++) {
struct mp_decoder_entry *ex = &remove->entries[n];
struct mp_decoder_entry *del =
find_decoder(list, bstr0(ex->family), bstr0(ex->decoder));
if (del) {
int index = del - &list->entries[0];
MP_TARRAY_REMOVE_AT(list->entries, list->num_entries, index);
}
}
talloc_free(remove);
return list;
}
// selection is a ","-separated list of decoders, all in the given family.
struct mp_decoder_list *mp_select_decoder_list(struct mp_decoder_list *all,
const char *codec,
const char *family,
const char *selection)
{
struct mp_decoder_list *list = talloc_zero(NULL, struct mp_decoder_list);
bstr sel = bstr0(selection);
while (sel.len) {
bstr decoder;
bstr_split_tok(sel, ",", &decoder, &sel);
add_new(list, find_decoder(all, bstr0(family), decoder), codec);
}
return list;
}
void mp_append_decoders(struct mp_decoder_list *list, struct mp_decoder_list *a)
{
for (int n = 0; n < a->num_entries; n++)
add_new(list, &a->entries[n], NULL);
}
void mp_print_decoders(struct mp_log *log, int msgl, const char *header,
struct mp_decoder_list *list)
{
mp_msg(log, msgl, "%s\n", header);
for (int n = 0; n < list->num_entries; n++) {
struct mp_decoder_entry *entry = &list->entries[n];
mp_msg(log, msgl, " %s:%s", entry->family, entry->decoder);
if (strcmp(entry->decoder, entry->codec) != 0)
mp_msg(log, msgl, " (%s)", entry->codec);
mp_msg(log, msgl, " - %s\n", entry->desc);
}
if (list->num_entries == 0)
mp_msg(log, msgl, " (no decoders)\n");
}