/* * midiparse - midi parser plugin for gstreamer * * Copyright 2013 Wim Taymans * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library 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 * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, * Boston, MA 02110-1301, USA. */ /** * SECTION:element-midiparse * @see_also: fluidsynth * * This element parses midi-files into midi events. You would need a midi * renderer such as fluidsynth to convert the events into raw samples. * * * Example pipeline * |[ * gst-launch-1.0 filesrc location=song.mid ! midiparse ! fluidsynth ! pulsesink * ]| This example pipeline will parse the midi and render to raw audio which is * played via pulseaudio. * */ #ifdef HAVE_CONFIG_H # include #endif #include #include #include #include "midiparse.h" GST_DEBUG_CATEGORY_STATIC (gst_midi_parse_debug); #define GST_CAT_DEFAULT gst_midi_parse_debug enum { /* FILL ME */ LAST_SIGNAL }; enum { PROP_0, /* FILL ME */ }; typedef struct { guint8 *data; guint size; guint offset; guint8 running_status; GstClockTime position; } GstMidiTrack; static void gst_midi_parse_finalize (GObject * object); static gboolean gst_midi_parse_sink_event (GstPad * pad, GstObject * parent, GstEvent * event); static gboolean gst_midi_parse_src_event (GstPad * pad, GstObject * parent, GstEvent * event); static GstStateChangeReturn gst_midi_parse_change_state (GstElement * element, GstStateChange transition); static gboolean gst_midi_parse_activate (GstPad * pad, GstObject * parent); static gboolean gst_midi_parse_activatemode (GstPad * pad, GstObject * parent, GstPadMode mode, gboolean active); static void gst_midi_parse_loop (GstPad * sinkpad); static GstFlowReturn gst_midi_parse_chain (GstPad * sinkpad, GstObject * parent, GstBuffer * buffer); static gboolean gst_midi_parse_src_query (GstPad * pad, GstObject * parent, GstQuery * query); static void gst_midi_parse_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec); static void gst_midi_parse_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec); static GstStaticPadTemplate sink_factory = GST_STATIC_PAD_TEMPLATE ("sink", GST_PAD_SINK, GST_PAD_ALWAYS, GST_STATIC_CAPS ("audio/midi; audio/riff-midi") ); static GstStaticPadTemplate src_factory = GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC, GST_PAD_ALWAYS, GST_STATIC_CAPS ("audio/x-midi-event")); #define parent_class gst_midi_parse_parent_class G_DEFINE_TYPE (GstMidiParse, gst_midi_parse, GST_TYPE_ELEMENT); /* initialize the plugin's class */ static void gst_midi_parse_class_init (GstMidiParseClass * klass) { GObjectClass *gobject_class; GstElementClass *gstelement_class; gobject_class = (GObjectClass *) klass; gstelement_class = (GstElementClass *) klass; gobject_class->finalize = gst_midi_parse_finalize; gobject_class->set_property = gst_midi_parse_set_property; gobject_class->get_property = gst_midi_parse_get_property; gst_element_class_add_pad_template (gstelement_class, gst_static_pad_template_get (&src_factory)); gst_element_class_add_pad_template (gstelement_class, gst_static_pad_template_get (&sink_factory)); gst_element_class_set_static_metadata (gstelement_class, "MidiParse", "Codec/Decoder/Audio", "Midi Parser Element", "Wim Taymans "); GST_DEBUG_CATEGORY_INIT (gst_midi_parse_debug, "midiparse", 0, "MIDI parser plugin"); gstelement_class->change_state = gst_midi_parse_change_state; } /* initialize the new element * instantiate pads and add them to element * set functions * initialize structure */ static void gst_midi_parse_init (GstMidiParse * filter) { filter->sinkpad = gst_pad_new_from_static_template (&sink_factory, "sink"); gst_pad_set_activatemode_function (filter->sinkpad, gst_midi_parse_activatemode); gst_pad_set_activate_function (filter->sinkpad, gst_midi_parse_activate); gst_pad_set_event_function (filter->sinkpad, gst_midi_parse_sink_event); gst_pad_set_chain_function (filter->sinkpad, gst_midi_parse_chain); gst_element_add_pad (GST_ELEMENT (filter), filter->sinkpad); filter->srcpad = gst_pad_new_from_static_template (&src_factory, "src"); gst_pad_set_query_function (filter->srcpad, gst_midi_parse_src_query); gst_pad_set_event_function (filter->srcpad, gst_midi_parse_src_event); gst_pad_use_fixed_caps (filter->srcpad); gst_element_add_pad (GST_ELEMENT (filter), filter->srcpad); gst_segment_init (&filter->segment, GST_FORMAT_TIME); filter->adapter = gst_adapter_new (); } static void gst_midi_parse_finalize (GObject * object) { GstMidiParse *midiparse; midiparse = GST_MIDI_PARSE (object); g_object_unref (midiparse->adapter); G_OBJECT_CLASS (parent_class)->finalize (object); } static gboolean gst_midi_parse_src_query (GstPad * pad, GstObject * parent, GstQuery * query) { gboolean res = TRUE; GstMidiParse *midiparse = GST_MIDI_PARSE (parent); switch (GST_QUERY_TYPE (query)) { case GST_QUERY_DURATION: gst_query_set_duration (query, GST_FORMAT_TIME, midiparse->segment.duration); break; case GST_QUERY_POSITION: gst_query_set_position (query, GST_FORMAT_TIME, midiparse->segment.position); break; case GST_QUERY_FORMATS: gst_query_set_formats (query, 1, GST_FORMAT_TIME); break; case GST_QUERY_SEGMENT: gst_query_set_segment (query, midiparse->segment.rate, midiparse->segment.format, midiparse->segment.start, midiparse->segment.stop); break; case GST_QUERY_SEEKING: gst_query_set_seeking (query, midiparse->segment.format, FALSE, 0, midiparse->segment.duration); break; default: res = gst_pad_query_default (pad, parent, query); break; } return res; } static gboolean gst_midi_parse_src_event (GstPad * pad, GstObject * parent, GstEvent * event) { gboolean res = FALSE; GST_DEBUG_OBJECT (pad, "%s event received", GST_EVENT_TYPE_NAME (event)); switch (GST_EVENT_TYPE (event)) { default: break; } gst_event_unref (event); return res; } static gboolean gst_midi_parse_activate (GstPad * sinkpad, GstObject * parent) { GstQuery *query; gboolean pull_mode; query = gst_query_new_scheduling (); if (!gst_pad_peer_query (sinkpad, query)) { gst_query_unref (query); goto activate_push; } pull_mode = gst_query_has_scheduling_mode_with_flags (query, GST_PAD_MODE_PULL, GST_SCHEDULING_FLAG_SEEKABLE); gst_query_unref (query); if (!pull_mode) goto activate_push; GST_DEBUG_OBJECT (sinkpad, "activating pull"); return gst_pad_activate_mode (sinkpad, GST_PAD_MODE_PULL, TRUE); activate_push: { GST_DEBUG_OBJECT (sinkpad, "activating push"); return gst_pad_activate_mode (sinkpad, GST_PAD_MODE_PUSH, TRUE); } } static gboolean gst_midi_parse_activatemode (GstPad * pad, GstObject * parent, GstPadMode mode, gboolean active) { gboolean res; switch (mode) { case GST_PAD_MODE_PUSH: res = TRUE; break; case GST_PAD_MODE_PULL: if (active) { res = gst_pad_start_task (pad, (GstTaskFunction) gst_midi_parse_loop, pad, NULL); } else { res = gst_pad_stop_task (pad); } break; default: res = FALSE; break; } return res; } static gboolean parse_MThd (GstMidiParse * midiparse, guint8 * data, guint size) { guint16 format, ntracks, division; gboolean multitrack; format = GST_READ_UINT16_BE (data); switch (format) { case 0: multitrack = FALSE; break; case 1: multitrack = TRUE; break; default: case 2: goto invalid_format; } ntracks = GST_READ_UINT16_BE (data + 2); if (ntracks > 1 && !multitrack) goto invalid_tracks; division = GST_READ_UINT16_BE (data + 4); if (division & 0x8000) goto invalid_division; GST_DEBUG_OBJECT (midiparse, "format %u, tracks %u, division %u", format, ntracks, division); midiparse->ntracks = ntracks; midiparse->division = division; return TRUE; invalid_format: { GST_ERROR_OBJECT (midiparse, "unsupported midi format %u", format); return FALSE; } invalid_tracks: { GST_ERROR_OBJECT (midiparse, "invalid number of tracks %u for format %u", ntracks, format); return FALSE; } invalid_division: { GST_ERROR_OBJECT (midiparse, "unsupported division"); return FALSE; } } static guint parse_varlen (GstMidiParse * midiparse, guint8 * data, guint size, gint32 * result) { gint32 res; gint i; res = 0; for (i = 0; i < 4; i++) { if (size == 0) return 0; res = (res << 7) | ((data[i]) & 0x7f); if ((data[i] & 0x80) == 0) { *result = res; return i + 1; } } return 0; } static gboolean update_track_position (GstMidiParse * midiparse, GstMidiTrack * track) { gint32 delta_time; guint8 *data; guint size, consumed; if (track->offset >= track->size) goto eot; data = track->data + track->offset; size = track->size - track->offset; consumed = parse_varlen (midiparse, data, size, &delta_time); if (consumed == 0) goto eot; track->position += delta_time; track->offset += consumed; GST_LOG_OBJECT (midiparse, "updated track to %" GST_TIME_FORMAT, GST_TIME_ARGS (track->position)); return TRUE; /* ERRORS */ eot: { GST_DEBUG_OBJECT (midiparse, "track ended"); track->position = GST_CLOCK_TIME_NONE; return FALSE; } } static gboolean parse_MTrk (GstMidiParse * midiparse, guint8 * data, guint size) { GstMidiTrack *track; track = g_slice_new (GstMidiTrack); track->data = data; track->size = size; track->offset = 0; track->position = 0; track->running_status = 0xff; update_track_position (midiparse, track); midiparse->tracks = g_list_append (midiparse->tracks, track); return TRUE; } static guint gst_midi_parse_chunk (GstMidiParse * midiparse, guint8 * data, guint size) { guint32 type, length = 0; if (size < 8) goto short_chunk; length = GST_READ_UINT32_BE (data + 4); GST_DEBUG_OBJECT (midiparse, "have type %c%c%c%c, length %u", data[0], data[1], data[2], data[3], length); if (size < length + 8) goto short_chunk; type = GST_STR_FOURCC (data); switch (type) { case GST_MAKE_FOURCC ('M', 'T', 'h', 'd'): if (!parse_MThd (midiparse, data + 8, length)) goto invalid_format; break; case GST_MAKE_FOURCC ('M', 'T', 'r', 'k'): if (!parse_MTrk (midiparse, data + 8, length)) goto invalid_format; break; default: GST_LOG_OBJECT (midiparse, "ignore chunk"); break; } return length + 8; /* ERRORS */ short_chunk: { GST_LOG_OBJECT (midiparse, "not enough data %u < %u", length + 8, size); return 0; } invalid_format: { GST_ERROR_OBJECT (midiparse, "invalid format"); return 0; } } static GstFlowReturn gst_midi_parse_parse_song (GstMidiParse * midiparse) { GstCaps *outcaps; guint8 *data; guint size; GST_DEBUG_OBJECT (midiparse, "Parsing song"); size = gst_adapter_available (midiparse->adapter); data = gst_adapter_take (midiparse->adapter, size); midiparse->tempo = 60; while (size) { guint consumed; consumed = gst_midi_parse_chunk (midiparse, data, size); if (consumed == 0) goto short_file; data += consumed; size -= consumed; } outcaps = gst_pad_get_pad_template_caps (midiparse->srcpad); gst_pad_set_caps (midiparse->srcpad, outcaps); gst_caps_unref (outcaps); gst_segment_init (&midiparse->segment, GST_FORMAT_TIME); gst_pad_push_event (midiparse->srcpad, gst_event_new_segment (&midiparse->segment)); GST_DEBUG_OBJECT (midiparse, "Parsing song done"); return GST_FLOW_OK; /* ERRORS */ short_file: { GST_ERROR_OBJECT (midiparse, "not enough data"); g_free (data); return GST_FLOW_ERROR; } } static GstFlowReturn handle_meta_event (GstMidiParse * midiparse, GstMidiTrack * track) { guint8 type; guint8 *data; guint size, consumed; gint32 length; track->offset += 1; data = track->data + track->offset; size = track->size - track->offset; if (size < 1) goto short_file; type = data[0]; consumed = parse_varlen (midiparse, data + 1, size - 1, &length); if (consumed == 0) goto short_file; data += consumed + 1; size -= consumed + 1; GST_DEBUG_OBJECT (midiparse, "handle meta event type 0x%02x, length %u", type, length); switch (type) { case 0x51: { guint32 uspqn = (data[0] << 16) | (data[1] << 8) | data[2]; midiparse->tempo = (uspqn ? uspqn : 1); GST_DEBUG_OBJECT (midiparse, "tempo %u", midiparse->tempo); break; } default: break; } track->offset += consumed + length + 1; return GST_FLOW_OK; /* ERRORS */ short_file: { GST_DEBUG_OBJECT (midiparse, "not enough data"); return GST_FLOW_ERROR; } } static GstFlowReturn handle_sysex_event (GstMidiParse * midiparse, guint8 event, GstMidiTrack * track) { guint8 *data; guint size, consumed; gint32 length; track->offset += 1; data = track->data + track->offset; size = track->size - track->offset; consumed = parse_varlen (midiparse, data, size, &length); if (consumed == 0) goto short_file; data += consumed; size -= consumed; GST_DEBUG_OBJECT (midiparse, "handle sysex event 0x%02x, length %u", event, length); track->offset += consumed + length; return GST_FLOW_OK; /* ERRORS */ short_file: { GST_DEBUG_OBJECT (midiparse, "not enough data"); return GST_FLOW_ERROR; } } static GstFlowReturn handle_next_event (GstMidiParse * midiparse, GstMidiTrack * track) { GstFlowReturn ret = GST_FLOW_OK; guint8 status, event; guint length; guint8 *data; data = &track->data[track->offset]; status = data[0]; GST_LOG_OBJECT (midiparse, "track %p, status 0x%02x", track, status); if ((status & 0x80) == 0) { if ((track->running_status & 0x80) == 0) goto undefined_status; event = track->running_status; } else { event = status; } switch (event & 0xf0) { case 0xf0: switch (event) { case 0xff: ret = handle_meta_event (midiparse, track); break; case 0xf0: case 0xf7: ret = handle_sysex_event (midiparse, event, track); break; default: GST_ERROR_OBJECT (midiparse, "unhandled event 0x%08x", event); return GST_FLOW_ERROR; } length = 0; break; case 0xc0: case 0xd0: length = 1; break; default: length = 2; break; } if (length > 0) { GstBuffer *outbuf; GstMapInfo info; outbuf = gst_buffer_new_allocate (NULL, length + 1, NULL); gst_buffer_map (outbuf, &info, GST_MAP_WRITE); info.data[0] = event; if (status & 0x80) { memcpy (&info.data[1], &data[1], length); track->offset += length + 1; } else { info.data[1] = status; memcpy (&info.data[2], &data[1], length - 1); track->offset += length; } gst_buffer_unmap (outbuf, &info); GST_BUFFER_PTS (outbuf) = gst_util_uint64_scale (track->position, 1000 * midiparse->tempo, midiparse->division); GST_BUFFER_DTS (outbuf) = GST_BUFFER_PTS (outbuf); GST_DEBUG_OBJECT (midiparse, "pushing %" GST_TIME_FORMAT, GST_TIME_ARGS (GST_BUFFER_PTS (outbuf))); ret = gst_pad_push (midiparse->srcpad, outbuf); } if (event < 0xF8) track->running_status = event; return ret; /* ERRORS */ undefined_status: { GST_ERROR_OBJECT (midiparse, "Undefined status and invalid running status"); return GST_FLOW_ERROR; } } static GstFlowReturn gst_midi_parse_do_play (GstMidiParse * midiparse) { GstFlowReturn res = GST_FLOW_OK; GList *walk; guint64 position, next_position = GST_CLOCK_TIME_NONE; position = midiparse->segment.position; for (walk = midiparse->tracks; walk; walk = g_list_next (walk)) { GstMidiTrack *track = walk->data; while (track->position == position) { res = handle_next_event (midiparse, track); if (res != GST_FLOW_OK) goto done; update_track_position (midiparse, track); } if (track->position < next_position) next_position = track->position; } if (next_position == GST_CLOCK_TIME_NONE) goto eos; midiparse->segment.position = next_position; done: return res; eos: { GST_DEBUG_OBJECT (midiparse, "we are EOS"); return GST_FLOW_EOS; } } static gboolean gst_midi_parse_sink_event (GstPad * pad, GstObject * parent, GstEvent * event) { gboolean res; GstMidiParse *midiparse = GST_MIDI_PARSE (parent); GST_DEBUG_OBJECT (pad, "%s event received", GST_EVENT_TYPE_NAME (event)); switch (GST_EVENT_TYPE (event)) { case GST_EVENT_EOS: midiparse->state = GST_MIDI_PARSE_STATE_PARSE; /* now start the parsing task */ res = gst_pad_start_task (midiparse->sinkpad, (GstTaskFunction) gst_midi_parse_loop, midiparse->sinkpad, NULL); /* don't forward the event */ gst_event_unref (event); break; default: res = gst_pad_event_default (pad, parent, event); break; } return res; } static GstFlowReturn gst_midi_parse_chain (GstPad * sinkpad, GstObject * parent, GstBuffer * buffer) { GstMidiParse *midiparse; midiparse = GST_MIDI_PARSE (parent); /* push stuff in the adapter, we will start doing something in the sink event * handler when we get EOS */ gst_adapter_push (midiparse->adapter, buffer); return GST_FLOW_OK; } static void gst_midi_parse_loop (GstPad * sinkpad) { GstMidiParse *midiparse = GST_MIDI_PARSE (GST_PAD_PARENT (sinkpad)); GstFlowReturn ret; switch (midiparse->state) { case GST_MIDI_PARSE_STATE_LOAD: { GstBuffer *buffer = NULL; GST_DEBUG_OBJECT (midiparse, "loading song"); ret = gst_pad_pull_range (midiparse->sinkpad, midiparse->offset, -1, &buffer); if (ret == GST_FLOW_EOS) { GST_DEBUG_OBJECT (midiparse, "Song loaded"); midiparse->state = GST_MIDI_PARSE_STATE_PARSE; } else if (ret != GST_FLOW_OK) { GST_ELEMENT_ERROR (midiparse, STREAM, DECODE, (NULL), ("Unable to read song")); goto pause; } else { GST_DEBUG_OBJECT (midiparse, "pushing buffer"); gst_adapter_push (midiparse->adapter, buffer); midiparse->offset += gst_buffer_get_size (buffer); } break; } case GST_MIDI_PARSE_STATE_PARSE: ret = gst_midi_parse_parse_song (midiparse); if (ret != GST_FLOW_OK) goto pause; midiparse->state = GST_MIDI_PARSE_STATE_PLAY; break; case GST_MIDI_PARSE_STATE_PLAY: ret = gst_midi_parse_do_play (midiparse); if (ret != GST_FLOW_OK) goto pause; break; default: break; } return; pause: { const gchar *reason = gst_flow_get_name (ret); GstEvent *event; GST_DEBUG_OBJECT (midiparse, "pausing task, reason %s", reason); gst_pad_pause_task (sinkpad); if (ret == GST_FLOW_EOS) { /* perform EOS logic */ event = gst_event_new_eos (); gst_pad_push_event (midiparse->srcpad, event); } else if (ret == GST_FLOW_NOT_LINKED || ret < GST_FLOW_EOS) { event = gst_event_new_eos (); /* for fatal errors we post an error message, post the error * first so the app knows about the error first. */ GST_ELEMENT_ERROR (midiparse, STREAM, FAILED, ("Internal data flow error."), ("streaming task paused, reason %s (%d)", reason, ret)); gst_pad_push_event (midiparse->srcpad, event); } } } static GstStateChangeReturn gst_midi_parse_change_state (GstElement * element, GstStateChange transition) { GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS; GstMidiParse *midiparse = GST_MIDI_PARSE (element); switch (transition) { case GST_STATE_CHANGE_NULL_TO_READY: break; case GST_STATE_CHANGE_READY_TO_PAUSED: midiparse->offset = 0; midiparse->state = GST_MIDI_PARSE_STATE_LOAD; midiparse->discont = FALSE; break; case GST_STATE_CHANGE_PAUSED_TO_PLAYING: break; default: break; } ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition); switch (transition) { case GST_STATE_CHANGE_PLAYING_TO_PAUSED: break; case GST_STATE_CHANGE_PAUSED_TO_READY: gst_adapter_clear (midiparse->adapter); break; case GST_STATE_CHANGE_READY_TO_NULL: break; default: break; } return ret; } static void gst_midi_parse_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec) { switch (prop_id) { default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static void gst_midi_parse_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec) { switch (prop_id) { default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } }