Files
2026-08-24 10:03:24 +08:00

306 lines
7.6 KiB
C

#include <string.h>
#include <gst/gst.h>
#include <gst/pbutils/pbutils.h>
/* Structure to contain all our information, so we can pass it around */
typedef struct _CustomData
{
GstDiscoverer *discoverer;
GMainLoop *loop;
gboolean has_video;
gboolean has_audio;
///< ...
} CustomData;
///< static api
/* Print a tag in a human-readable format (name: value) */
static void print_tag_foreach(const GstTagList *tags, const gchar *tag, gpointer user_data)
{
GValue val = {
0,
};
gchar *str;
gint depth = GPOINTER_TO_INT(user_data);
gst_tag_list_copy_value(&val, tags, tag);
if (G_VALUE_HOLDS_STRING(&val))
str = g_value_dup_string(&val);
else
str = gst_value_serialize(&val);
GST_DEBUG("%*s%s: %s\n", 2 * depth, " ", gst_tag_get_nick(tag), str);
g_free(str);
g_value_unset(&val);
}
/* Print information regarding a stream */
static void print_stream_info(GstDiscovererStreamInfo *info, gint depth, CustomData *data)
{
gchar *desc = NULL;
GstCaps *caps;
const GstTagList *tags;
const gchar *stream_info = NULL;
caps = gst_discoverer_stream_info_get_caps(info);
if (caps)
{
if (gst_caps_is_fixed(caps))
desc = gst_pb_utils_get_codec_description(caps);
else
desc = gst_caps_to_string(caps);
gst_caps_unref(caps);
}
stream_info = gst_discoverer_stream_info_get_stream_type_nick(info);
if (strstr(stream_info, "audio:"))
{
data->has_audio = TRUE;
}
if (strstr(stream_info, "video:"))
{
data->has_video = TRUE;
}
GST_DEBUG("%*s%s: %s\n", 2 * depth, " ", stream_info, (desc ? desc : ""));
if (desc)
{
g_free(desc);
desc = NULL;
}
tags = gst_discoverer_stream_info_get_tags(info);
if (tags)
{
GST_DEBUG("%*sTags:\n", 2 * (depth + 1), " ");
gst_tag_list_foreach(tags, print_tag_foreach, GINT_TO_POINTER(depth + 2));
}
}
/* Print information regarding a stream and its substreams, if any */
static void print_topology(GstDiscovererStreamInfo *info, gint depth, CustomData *data)
{
GstDiscovererStreamInfo *next;
if (!info)
return;
print_stream_info(info, depth, data);
next = gst_discoverer_stream_info_get_next(info);
if (next)
{
print_topology(next, depth + 1, data);
gst_discoverer_stream_info_unref(next);
}
else if (GST_IS_DISCOVERER_CONTAINER_INFO(info))
{
GList *tmp, *streams;
streams = gst_discoverer_container_info_get_streams(GST_DISCOVERER_CONTAINER_INFO(info));
for (tmp = streams; tmp; tmp = tmp->next)
{
GstDiscovererStreamInfo *tmpinf = (GstDiscovererStreamInfo *)tmp->data;
print_topology(tmpinf, depth + 1, data);
}
gst_discoverer_stream_info_list_free(streams);
}
}
/* This function is called every time the discoverer has information regarding
* one of the URIs we provided.*/
static void on_discovered_cb(GstDiscoverer *discoverer, GstDiscovererInfo *info, GError *err, CustomData *data)
{
GstDiscovererResult result;
const gchar *uri;
const GstTagList *tags;
GstDiscovererStreamInfo *sinfo;
uri = gst_discoverer_info_get_uri(info);
result = gst_discoverer_info_get_result(info);
switch (result)
{
case GST_DISCOVERER_URI_INVALID:
GST_ERROR("Invalid URI '%s'\n", uri);
break;
case GST_DISCOVERER_ERROR:
GST_ERROR("Discoverer error: %s\n", err->message);
break;
case GST_DISCOVERER_TIMEOUT:
GST_ERROR("Timeout\n");
break;
case GST_DISCOVERER_BUSY:
GST_ERROR("Busy\n");
break;
case GST_DISCOVERER_MISSING_PLUGINS:
{
const GstStructure *s;
gchar *str;
s = gst_discoverer_info_get_misc(info);
str = gst_structure_to_string(s);
GST_ERROR("Missing plugins: %s\n", str);
g_free(str);
break;
}
case GST_DISCOVERER_OK:
GST_DEBUG("Discovered '%s'\n", uri);
break;
}
if (result != GST_DISCOVERER_OK)
{
g_printerr("This URI cannot be played\n");
return;
}
/* If we got no error, show the retrieved information */
GST_DEBUG("\nDuration: %" GST_TIME_FORMAT "\n", GST_TIME_ARGS(gst_discoverer_info_get_duration(info)));
tags = gst_discoverer_info_get_tags(info);
if (tags)
{
GST_DEBUG("Tags:\n");
gst_tag_list_foreach(tags, print_tag_foreach, GINT_TO_POINTER(1));
}
GST_DEBUG("Seekable: %s\n", (gst_discoverer_info_get_seekable(info) ? "yes" : "no"));
GST_DEBUG("\n");
sinfo = gst_discoverer_info_get_stream_info(info);
if (!sinfo)
return;
GST_DEBUG("Stream information:\n");
print_topology(sinfo, 1, data);
gst_discoverer_stream_info_unref(sinfo);
GST_DEBUG("\n");
}
/* This function is called when the discoverer has finished examining
* all the URIs we provided.*/
static void on_finished_cb(GstDiscoverer *discoverer, CustomData *data)
{
GST_DEBUG("Finished discovering\n");
g_main_loop_quit(data->loop);
}
///< extern api
int discoverer_create(void **p_hdl)
{
/* Check input param */
if (NULL == p_hdl)
{
GST_ERROR("invalid param!\n");
return -1;
}
GError *err = NULL;
CustomData *data = (CustomData *)malloc(sizeof(CustomData));
if (NULL == data)
{
return -1;
}
memset(data, 0, sizeof(CustomData));
/* Initialize GStreamer */
gst_init(NULL, NULL);
/* Instantiate the Discoverer */
data->discoverer = gst_discoverer_new(5 * GST_SECOND, &err);
if (!data->discoverer)
{
GST_ERROR("Error creating discoverer instance: %s\n", err->message);
g_clear_error(&err);
return -1;
}
/* Connect to the interesting signals */
g_signal_connect(data->discoverer, "discovered", G_CALLBACK(on_discovered_cb), data);
g_signal_connect(data->discoverer, "finished", G_CALLBACK(on_finished_cb), data);
/* Create a GLib Main Loop */
data->loop = g_main_loop_new(NULL, FALSE);
*p_hdl = data;
return 0;
}
int discoverer_destroy(void *hdl)
{
/* Check input param */
if (NULL == hdl)
{
GST_ERROR("invalid param!\n");
return -1;
}
CustomData *data = (CustomData *)hdl;
/* Stop the discoverer process */
gst_discoverer_stop(data->discoverer);
/* Free resources */
g_object_unref(data->discoverer);
g_main_loop_unref(data->loop);
free(data);
return 0;
}
int discoverer_run(void *hdl, char *uri)
{
/* Check input param */
if (NULL == hdl || NULL == uri)
{
GST_ERROR("invalid param!\n");
return -1;
}
CustomData *data = (CustomData *)hdl;
/* Start the discoverer process (nothing to do yet) */
gst_discoverer_start(data->discoverer);
/* Add a request to process asynchronously the URI passed through the command line */
if (!gst_discoverer_discover_uri_async(data->discoverer, uri))
{
GST_ERROR("Failed to start discovering URI '%s'\n", uri);
g_object_unref(data->discoverer);
return -1;
}
g_main_loop_run(data->loop);
return 0;
}
int discoverer_has_video(void *hdl)
{
/* Check input param */
if (NULL == hdl)
{
GST_ERROR("invalid param!\n");
return -1;
}
CustomData *data = (CustomData *)hdl;
return data->has_video ? 0 : 1;
}
int discoverer_has_audio(void *hdl)
{
/* Check input param */
if (NULL == hdl)
{
GST_ERROR("invalid param!\n");
return -1;
}
CustomData *data = (CustomData *)hdl;
return data->has_audio ? 0 : 1;
}