décoder une vidéo mp4 avec gstreamer
Je veux lire une vidéo MP4 dans Gstreamer, mais j'ai une erreur avec le x264dec qui n'est pas trouvée. J'ai écrit ce pipeline
gst-launch filesrc \
location=/media/thesis/Gstreamer/pub_Irma.mp4 \
! qtdemux name=demux demux. ! queue ! faad \
! audioconvert ! audioresample ! autoaudiosink demuxer. \
! queue ! x264dec ! ffmpegcolorspace ! autovideosink
Après cette étape, mon objectif est de générer des traces d’exécution d’un décodage vidéo MP4. Je ne sais pas où est le problème avec x264dec.
Je ne pense pas qu'il existe un élément x264dec (je ne connais que l'élément x264enc). Vous voudrez peut-être utiliser ffdec_h264 comme dans this nabble post :
gst-launch-0.10 filesrc location=$1 ! h264parse ! ffdec_h264 ! ffmpegcolorspace ! deinterlace ! xvimagesink
Cela pourrait être plus facile:
gst-launch-0.10 playbin2 uri=file:///path/to/foo.mp4
ou
gst-launch-1.0 playbin uri=file:///path/to/foo.mp4
(Vous devez toujours installer les éléments requis, bien sûr).
J'ai un nom de fichier tuhi.mp4 dans le bureau. Donc, la commande va dans ce sens.
$ gst-launch-1.0 filesrc location=~/Desktop/tuhi.mp4 ! decodebin name=dec ! videoconvert ! autovideosink dec. ! audioconvert ! audioresample ! alsasink
#include <gst/gst.h>
typedef struct _CustomData {
GstElement *pipeline;
GstElement *source;
GstElement *demuxer;
GstElement *audioqueue;
GstElement *videoqueue;
GstElement *audio_decoder;
GstElement *video_decoder;
GstElement *video_convert;
GstElement *audio_convert;
GstElement *video_sink;
GstElement *audio_sink;
} CustomData;
static void pad_added_handler (GstElement *src, GstPad *pad, CustomData *data);
int main(int argc, char *argv[]) {
CustomData data;
GstBus *bus;
GstMessage *msg;
GstStateChangeReturn ret;
gboolean terminate = FALSE;
/* Initialize GStreamer */
gst_init (&argc, &argv);
/* Create the elements */
data.source = gst_element_factory_make ("filesrc", "source");
data.demuxer = gst_element_factory_make ("oggdemux", "demuxer");
data.audioqueue = gst_element_factory_make("queue","audioqueue");
data.videoqueue = gst_element_factory_make("queue","videoqueue");
data.audio_decoder = gst_element_factory_make ("vorbisdec", "audio_decoder");
data.audio_convert = gst_element_factory_make ("audioconvert", "audio_convert");
data.audio_sink = gst_element_factory_make ("autoaudiosink", "audio_sink");
data.video_decoder = gst_element_factory_make("theoradec","video_decoder");
data.video_convert = gst_element_factory_make("ffmpegcolorspace","video_convert");
data.video_sink = gst_element_factory_make("autovideosink","video_sink");
data.pipeline = gst_pipeline_new ("test-pipeline");
if (!data.pipeline || !data.source || !data.demuxer || !data.audioqueue ||!data.audio_decoder ||!data.audio_convert ||
!data.audio_sink || !data.videoqueue || !data.video_decoder || !data.video_convert || !data.video_sink) {
g_printerr ("Not all elements could be created.\n");
return -1;
}
gst_bin_add_many (GST_BIN (data.pipeline), data.source,data.demuxer,data.audioqueue,data.audio_decoder,data.audio_convert,data.audio_sink,data.videoqueue,data.video_decoder,data.video_convert,data.video_sink, NULL);
if (!gst_element_link(data.source,data.demuxer)) {
g_printerr ("Elements could not be linked.\n");
gst_object_unref (data.pipeline);
return -1;
}
if (!gst_element_link_many (data.audioqueue,data.audio_decoder,data.audio_convert, data.audio_sink,NULL)) {
g_printerr (" audio Elements could not be linked.\n");
gst_object_unref (data.pipeline);
return -1;
}
if (!gst_element_link_many(data.videoqueue,data.video_decoder,data.video_convert, data.video_sink,NULL)) {
g_printerr("video Elements could not be linked.\n");
gst_object_unref(data.pipeline);
return -1;
}
/* Set the file to play */
g_object_set (data.source, "location", argv[1], NULL);
g_signal_connect (data.demuxer, "pad-added", G_CALLBACK (pad_added_handler), &data);
/* Start playing */
ret = gst_element_set_state (data.pipeline, GST_STATE_PLAYING);
if (ret == GST_STATE_CHANGE_FAILURE) {
g_printerr ("Unable to set the pipeline to the playing state.\n");
gst_object_unref (data.pipeline);
return -1;
}
/* Listen to the bus */
bus = gst_element_get_bus (data.pipeline);
do {
msg = gst_bus_timed_pop_filtered (bus, GST_CLOCK_TIME_NONE,
GST_MESSAGE_STATE_CHANGED | GST_MESSAGE_ERROR | GST_MESSAGE_EOS);
if (msg != NULL) {
GError *err;
gchar *debug_info;
switch (GST_MESSAGE_TYPE (msg)) {
case GST_MESSAGE_ERROR:
gst_message_parse_error (msg, &err, &debug_info);
g_printerr ("Error received from element %s: %s\n", GST_OBJECT_NAME (msg->src), err->message);
g_printerr ("Debugging information: %s\n", debug_info ? debug_info : "none");
g_clear_error (&err);
g_free (debug_info);
terminate = TRUE;
break;
case GST_MESSAGE_EOS:
g_print ("End-Of-Stream reached.\n");
terminate = TRUE;
break;
case GST_MESSAGE_STATE_CHANGED:
if (GST_MESSAGE_SRC (msg) == GST_OBJECT (data.pipeline)) {
GstState old_state, new_state, pending_state;
gst_message_parse_state_changed (msg, &old_state, &new_state, &pending_state);
g_print ("Pipeline state changed from %s to %s:\n",
gst_element_state_get_name (old_state), gst_element_state_get_name (new_state));
}
break;
default:
g_printerr ("Unexpected message received.\n");
break;
}
gst_message_unref (msg);
}
} while (!terminate);
gst_object_unref (bus);
gst_element_set_state (data.pipeline, GST_STATE_NULL);
gst_object_unref (data.pipeline);
return 0;
}
/* This function will be called by the pad-added signal */
static void pad_added_handler (GstElement *src, GstPad *new_pad, CustomData *data) {
g_print("Inside the pad_added_handler method \n");
GstPad *sink_pad_audio = gst_element_get_static_pad (data->audioqueue, "sink");
GstPad *sink_pad_video = gst_element_get_static_pad (data->videoqueue, "sink");
GstPadLinkReturn ret;
GstCaps *new_pad_caps = NULL;
GstStructure *new_pad_struct = NULL;
const gchar *new_pad_type = NULL;
g_print ("Received new pad '%s' from '%s':\n", GST_PAD_NAME (new_pad), GST_ELEMENT_NAME (src));
new_pad_caps = gst_pad_get_caps (new_pad);
new_pad_struct = gst_caps_get_structure (new_pad_caps, 0);
new_pad_type = gst_structure_get_name (new_pad_struct);
if (g_str_has_prefix (new_pad_type,"audio/x-vorbis" /*"audio/mpeg"*/))
{
ret = gst_pad_link (new_pad, sink_pad_audio);
if (GST_PAD_LINK_FAILED (ret))
{
g_print (" Type is '%s' but link failed.\n", new_pad_type);
}
else
{
g_print (" Link succeeded (type '%s').\n", new_pad_type);
}
}
else if (g_str_has_prefix (new_pad_type, "video/x-theora"/*"video/x-h264"*/))
{
ret = gst_pad_link (new_pad, sink_pad_video);
if (GST_PAD_LINK_FAILED (ret))
{
g_print (" Type is '%s' but link failed.\n", new_pad_type);
}
else
{
g_print (" Link succeeded (type '%s').\n", new_pad_type);
}
}
else {
g_print (" It has type '%s' which is not raw audio. Ignoring.\n", new_pad_type);
goto exit;
}
exit:
if (new_pad_caps != NULL)
gst_caps_unref (new_pad_caps);
gst_object_unref (sink_pad_audio);
gst_object_unref (sink_pad_video);
}
Cette commande
gst-launch-0.10 filesrc location=/root/gstreamerexamples/big.mp4 ! qtdemux name=demux demux. ! queue ! faad ! audioconvert ! audioresample ! autoaudiosink demux. ! queue ! ffdec_h264 ! ffmpegcolorspace ! autovideosink
fonctionne bien pour moi.
Pour lire le fichier mp4, prenez la vidéo bigBuckBunny mp4 en tant que fichier test. Ensuite, veuillez vous assurer que tous les éléments mentionnés dans le fichier gst-launch sont intégrés à la plate-forme x86 ou à une autre.
S'il vous plaît envoyez beaucoup de temps dans l'installation correcte de GStreamer.
J'ai un fichier ogg sur mon bureau, donc la commande va de cette façon.
$ gst-launch-1.0 filesrc location=~/Desktop/test.ogg ! oggdemux name=demuxer \
demuxer. ! queue ! vorbisdec ! audioconvert ! audioresample ! autoaudiosink \
demuxer. ! queue ! theoradec ! videoconvert ! autovideosink
Cela fonctionnera également pour gstreamer 0.10 mais il faudra remplacer vidéoconverti par ffmpegcolorspace