command: export list of all decoders

Was only available via --vd=help and --ad=help (i.e. not at all via
client API). Not bothering with separating audio and video codecs, since
this list isn't all that useful anyway in general. If someone complains,
a type field could be added.

2 files changed, 64 insertions, 0 deletions

diff --git a/DOCS/man/input.rst b/DOCS/man/input.rst
index 9918f7384f..726354eafa 100644
--- a/DOCS/man/input.rst
+++ b/DOCS/man/input.rst
@@ -1988,6 +1988,38 @@ Property list
     In some cases, the protocol will not actually be supported (consider
     ``https`` if ffmpeg is not compiled with TLS support).
 
+``decoder-list``
+    List of decoders supported. This lists decoders which can be passed to
+    ``--vd`` and ``--ad``.
+
+    ``family``
+        Decoder driver. Usually ``lavc`` for libavcodec.
+
+    ``codec``
+        Canonical codec name, which identifies the format the decoder can
+        handle.
+
+    ``decoder``
+        The name of the decoder itself. Often, this is the same as ``codec``.
+        Sometimes it can be different. It is used to distinguish multiple
+        decoders for the same codec.
+
+    ``description``
+        Human readable description of the decoder and codec.
+
+    When querying the property with the client API using ``MPV_FORMAT_NODE``,
+    or with Lua ``mp.get_property_native``, this will return a mpv_node with
+    the following contents:
+
+    ::
+
+        MPV_FORMAT_NODE_ARRAY
+            MPV_FORMAT_NODE_MAP (for each decoder entry)
+                "family"        MPV_FORMAT_STRING
+                "codec"         MPV_FORMAT_STRING
+                "decoder"       MPV_FORMAT_STRING
+                "description"   MPV_FORMAT_STRING
+
 ``mpv-version``
     Return the mpv version/copyright string. Depending on how the binary was
     built, it might contain either a release version, or just a git hash.
diff --git a/player/command.c b/player/command.c
index 421f001573..f4a78e11fb 100644
--- a/player/command.c
+++ b/player/command.c
@@ -32,6 +32,7 @@
 #include "config.h"
 #include "mpv_talloc.h"
 #include "client.h"
+#include "common/codecs.h"
 #include "common/msg.h"
 #include "common/msg_control.h"
 #include "command.h"
@@ -3290,6 +3291,36 @@ static int mp_property_protocols(void *ctx, struct m_property *prop,
     return M_PROPERTY_NOT_IMPLEMENTED;
 }
 
+static int get_decoder_entry(int item, int action, void *arg, void *ctx)
+{
+    struct mp_decoder_list *codecs = ctx;
+    struct mp_decoder_entry *c = &codecs->entries[item];
+
+    struct m_sub_property props[] = {
+        {"family",      SUB_PROP_STR(c->family)},
+        {"codec",       SUB_PROP_STR(c->codec)},
+        {"decoder",     SUB_PROP_STR(c->decoder)},
+        {"description", SUB_PROP_STR(c->desc)},
+        {0}
+    };
+
+    return m_property_read_sub(props, action, arg);
+}
+
+static int mp_property_decoders(void *ctx, struct m_property *prop,
+                                int action, void *arg)
+{
+    struct mp_decoder_list *codecs = talloc_zero(NULL, struct mp_decoder_list);
+    struct mp_decoder_list *v = talloc_steal(codecs, video_decoder_list());
+    struct mp_decoder_list *a = talloc_steal(codecs, audio_decoder_list());
+    mp_append_decoders(codecs, v);
+    mp_append_decoders(codecs, a);
+    int r = m_property_read_list(action, arg, codecs->num_entries,
+                                 get_decoder_entry, codecs);
+    talloc_free(codecs);
+    return r;
+}
+
 static int mp_property_version(void *ctx, struct m_property *prop,
                                int action, void *arg)
 {
@@ -3707,6 +3738,7 @@ static const struct m_property mp_properties[] = {
     {"working-directory", mp_property_cwd},
 
     {"protocol-list", mp_property_protocols},
+    {"decoder-list", mp_property_decoders},
 
     {"mpv-version", mp_property_version},
     {"mpv-configuration", mp_property_configuration},