gstreamer/gst/midi/midiparse.c

1367 lines
34 KiB
C

/*
* midiparse - midi parser plugin for gstreamer
*
* Copyright 2013 Wim Taymans <wim.taymans@gmail.com>
*
* 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: fluiddec
*
* This element parses midi-files into midi events. You would need a midi
* renderer such as fluidsynth to convert the events into raw samples.
*
* <refsect2>
* <title>Example pipeline</title>
* |[
* gst-launch-1.0 filesrc location=song.mid ! midiparse ! fluiddec ! pulsesink
* ]| This example pipeline will parse the midi and render to raw audio which is
* played via pulseaudio.
* </refsect2>
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <gst/gst.h>
#include <string.h>
#include <glib.h>
#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 */
};
#define DEFAULT_TEMPO 500000 /* 120 BPM is the default */
typedef struct
{
guint8 *data;
guint size;
guint offset;
guint8 running_status;
guint64 pulse;
gboolean eot;
} GstMidiTrack;
typedef GstFlowReturn (*GstMidiPushFunc) (GstMidiParse * parse,
GstMidiTrack * track, guint8 event, guint8 * data, guint length,
gpointer user_data);
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 void reset_track (GstMidiTrack * track, GstMidiParse * midiparse);
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_static_pad_template (gstelement_class, &src_factory);
gst_element_class_add_static_pad_template (gstelement_class, &sink_factory);
gst_element_class_set_static_metadata (gstelement_class, "MidiParse",
"Codec/Demuxer/Audio",
"Midi Parser Element", "Wim Taymans <wim.taymans@gmail.com>");
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 ();
filter->have_group_id = FALSE;
filter->group_id = G_MAXUINT;
}
static void
gst_midi_parse_finalize (GObject * object)
{
GstMidiParse *midiparse;
midiparse = GST_MIDI_PARSE (object);
g_object_unref (midiparse->adapter);
g_free (midiparse->data);
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:{
GstFormat format;
gint64 start, stop;
format = midiparse->segment.format;
start =
gst_segment_to_stream_time (&midiparse->segment, format,
midiparse->segment.start);
if ((stop = midiparse->segment.stop) == -1)
stop = midiparse->segment.duration;
else
stop = gst_segment_to_stream_time (&midiparse->segment, format, stop);
gst_query_set_segment (query, midiparse->segment.rate, format, start,
stop);
res = TRUE;
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_do_seek (GstMidiParse * midiparse, GstSegment * segment)
{
/* if seeking backwards, start from 0 else we just let things run and
* have it clip downstream */
GST_DEBUG_OBJECT (midiparse, "seeking back to 0");
segment->position = 0;
g_list_foreach (midiparse->tracks, (GFunc) reset_track, midiparse);
midiparse->pulse = 0;
return TRUE;
}
static gboolean
gst_midi_parse_perform_seek (GstMidiParse * midiparse, GstEvent * event)
{
gboolean res = TRUE, tres;
gdouble rate;
GstFormat seek_format;
GstSeekFlags flags;
GstSeekType start_type, stop_type;
gint64 start, stop;
gboolean flush;
gboolean update;
GstSegment seeksegment;
guint32 seqnum;
GstEvent *tevent;
GST_DEBUG_OBJECT (midiparse, "doing seek: %" GST_PTR_FORMAT, event);
if (event) {
gst_event_parse_seek (event, &rate, &seek_format, &flags,
&start_type, &start, &stop_type, &stop);
if (seek_format != GST_FORMAT_TIME)
goto invalid_format;
flush = flags & GST_SEEK_FLAG_FLUSH;
seqnum = gst_event_get_seqnum (event);
} else {
flush = FALSE;
/* get next seqnum */
seqnum = gst_util_seqnum_next ();
}
/* send flush start */
if (flush) {
tevent = gst_event_new_flush_start ();
gst_event_set_seqnum (tevent, seqnum);
gst_pad_push_event (midiparse->srcpad, tevent);
} else
gst_pad_pause_task (midiparse->srcpad);
/* grab streaming lock, this should eventually be possible, either
* because the task is paused, our streaming thread stopped
* or because our peer is flushing. */
GST_PAD_STREAM_LOCK (midiparse->sinkpad);
if (G_UNLIKELY (midiparse->seqnum == seqnum)) {
/* we have seen this event before, issue a warning for now */
GST_WARNING_OBJECT (midiparse, "duplicate event found %" G_GUINT32_FORMAT,
seqnum);
} else {
midiparse->seqnum = seqnum;
GST_DEBUG_OBJECT (midiparse, "seek with seqnum %" G_GUINT32_FORMAT, seqnum);
}
/* Copy the current segment info into the temp segment that we can actually
* attempt the seek with. We only update the real segment if the seek succeeds. */
memcpy (&seeksegment, &midiparse->segment, sizeof (GstSegment));
/* now configure the final seek segment */
if (event) {
gst_segment_do_seek (&seeksegment, rate, seek_format, flags,
start_type, start, stop_type, stop, &update);
}
/* Else, no seek event passed, so we're just (re)starting the
current segment. */
GST_DEBUG_OBJECT (midiparse, "segment configured from %" G_GINT64_FORMAT
" to %" G_GINT64_FORMAT ", position %" G_GINT64_FORMAT,
seeksegment.start, seeksegment.stop, seeksegment.position);
/* do the seek, segment.position contains the new position. */
res = gst_midi_parse_do_seek (midiparse, &seeksegment);
/* and prepare to continue streaming */
if (flush) {
tevent = gst_event_new_flush_stop (TRUE);
gst_event_set_seqnum (tevent, seqnum);
/* send flush stop, peer will accept data and events again. We
* are not yet providing data as we still have the STREAM_LOCK. */
gst_pad_push_event (midiparse->srcpad, tevent);
}
/* if the seek was successful, we update our real segment and push
* out the new segment. */
if (res) {
GST_OBJECT_LOCK (midiparse);
memcpy (&midiparse->segment, &seeksegment, sizeof (GstSegment));
GST_OBJECT_UNLOCK (midiparse);
if (seeksegment.flags & GST_SEGMENT_FLAG_SEGMENT) {
GstMessage *message;
message = gst_message_new_segment_start (GST_OBJECT (midiparse),
seeksegment.format, seeksegment.position);
gst_message_set_seqnum (message, seqnum);
gst_element_post_message (GST_ELEMENT (midiparse), message);
}
/* for deriving a stop position for the playback segment from the seek
* segment, we must take the duration when the stop is not set */
if ((stop = seeksegment.stop) == -1)
stop = seeksegment.duration;
midiparse->segment_pending = TRUE;
midiparse->discont = TRUE;
}
/* and restart the task in case it got paused explicitly or by
* the FLUSH_START event we pushed out. */
tres =
gst_pad_start_task (midiparse->sinkpad,
(GstTaskFunction) gst_midi_parse_loop, midiparse->sinkpad, NULL);
if (res && !tres)
res = FALSE;
/* and release the lock again so we can continue streaming */
GST_PAD_STREAM_UNLOCK (midiparse->sinkpad);
return res;
/* ERROR */
invalid_format:
{
GST_DEBUG_OBJECT (midiparse, "Unsupported seek format %s",
gst_format_get_name (seek_format));
return FALSE;
}
}
static gboolean
gst_midi_parse_src_event (GstPad * pad, GstObject * parent, GstEvent * event)
{
gboolean res = FALSE;
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_SEEK:
res = gst_midi_parse_perform_seek (midiparse, event);
break;
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 GstFlowReturn
handle_meta_event (GstMidiParse * midiparse, GstMidiTrack * track, guint8 event)
{
guint8 type;
guint8 *data;
gchar *bytes;
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;
if (size < length)
goto short_file;
GST_DEBUG_OBJECT (midiparse, "handle meta event type 0x%02x, length %u",
type, length);
bytes = g_strndup ((const gchar *) data, length);
switch (type) {
case 0x01:
GST_DEBUG_OBJECT (midiparse, "Text: %s", bytes);
break;
case 0x02:
GST_DEBUG_OBJECT (midiparse, "Copyright: %s", bytes);
break;
case 0x03:
GST_DEBUG_OBJECT (midiparse, "Track Name: %s", bytes);
break;
case 0x04:
GST_DEBUG_OBJECT (midiparse, "Instrument: %s", bytes);
break;
case 0x05:
GST_DEBUG_OBJECT (midiparse, "Lyric: %s", bytes);
break;
case 0x06:
GST_DEBUG_OBJECT (midiparse, "Marker: %s", bytes);
break;
case 0x07:
GST_DEBUG_OBJECT (midiparse, "Cue point: %s", bytes);
break;
case 0x08:
GST_DEBUG_OBJECT (midiparse, "Patch name: %s", bytes);
break;
case 0x09:
GST_DEBUG_OBJECT (midiparse, "MIDI port: %s", bytes);
break;
case 0x2f:
GST_DEBUG_OBJECT (midiparse, "End of track");
break;
case 0x51:
{
guint32 uspqn = (data[0] << 16) | (data[1] << 8) | data[2];
midiparse->tempo = (uspqn ? uspqn : DEFAULT_TEMPO);
GST_DEBUG_OBJECT (midiparse, "tempo %u", midiparse->tempo);
break;
}
case 0x54:
GST_DEBUG_OBJECT (midiparse, "SMPTE offset");
break;
case 0x58:
GST_DEBUG_OBJECT (midiparse, "Time signature");
break;
case 0x59:
GST_DEBUG_OBJECT (midiparse, "Key signature");
break;
case 0x7f:
GST_DEBUG_OBJECT (midiparse, "Proprietary event");
break;
default:
GST_DEBUG_OBJECT (midiparse, "unknown event 0x%02x length %d", type,
length);
break;
}
g_free (bytes);
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, GstMidiTrack * track,
guint8 event, GstMidiPushFunc pushfunc, gpointer user_data)
{
GstFlowReturn ret;
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;
if (size < length)
goto short_file;
GST_DEBUG_OBJECT (midiparse, "handle sysex event 0x%02x, length %u",
event, length);
if (pushfunc)
ret = pushfunc (midiparse, track, event, data, length, user_data);
else
ret = GST_FLOW_OK;
track->offset += consumed + length;
return ret;
/* ERRORS */
short_file:
{
GST_DEBUG_OBJECT (midiparse, "not enough data");
return GST_FLOW_ERROR;
}
}
static guint8
event_from_status (GstMidiParse * midiparse, GstMidiTrack * track,
guint8 status)
{
if ((status & 0x80) == 0) {
if ((track->running_status & 0x80) == 0)
return 0;
return track->running_status;
} else {
return status;
}
}
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->pulse += delta_time;
track->offset += consumed;
GST_LOG_OBJECT (midiparse, "updated track to pulse %" G_GUINT64_FORMAT,
track->pulse);
return TRUE;
/* ERRORS */
eot:
{
GST_DEBUG_OBJECT (midiparse, "track ended");
track->eot = TRUE;
return FALSE;
}
}
static GstFlowReturn
handle_next_event (GstMidiParse * midiparse, GstMidiTrack * track,
GstMidiPushFunc pushfunc, gpointer user_data)
{
GstFlowReturn ret = GST_FLOW_OK;
guint8 status, event;
guint length;
guint8 *data;
data = &track->data[track->offset];
status = data[0];
event = event_from_status (midiparse, track, status);
GST_LOG_OBJECT (midiparse, "track %p, status 0x%02x, event 0x%02x", track,
status, event);
switch (event & 0xf0) {
case 0xf0:
switch (event) {
case 0xff:
ret = handle_meta_event (midiparse, track, event);
break;
case 0xf0:
case 0xf7:
ret =
handle_sysex_event (midiparse, track, event, pushfunc, user_data);
break;
default:
goto unhandled_event;
}
length = 0;
break;
case 0xc0:
case 0xd0:
length = 1;
break;
case 0x80:
case 0x90:
case 0xa0:
case 0xb0:
case 0xe0:
length = 2;
break;
default:
goto undefined_status;
}
if (length > 0) {
if (status & 0x80) {
if (pushfunc)
ret = pushfunc (midiparse, track, event, data + 1, length, user_data);
track->offset += length + 1;
} else {
if (pushfunc)
ret = pushfunc (midiparse, track, event, data, length + 1, user_data);
track->offset += length;
}
}
if (ret == GST_FLOW_OK) {
if (event < 0xF8)
track->running_status = event;
update_track_position (midiparse, track);
}
return ret;
/* ERRORS */
undefined_status:
{
GST_ERROR_OBJECT (midiparse, "Undefined status and invalid running status");
return GST_FLOW_ERROR;
}
unhandled_event:
{
/* we don't know the size so we can't continue parsing */
GST_ERROR_OBJECT (midiparse, "unhandled event 0x%08x", event);
return GST_FLOW_ERROR;
}
}
static void
reset_track (GstMidiTrack * track, GstMidiParse * midiparse)
{
GST_DEBUG_OBJECT (midiparse, "reset track");
track->offset = 0;
track->pulse = 0;
track->eot = FALSE;
track->running_status = 0xff;
update_track_position (midiparse, track);
}
static gboolean
parse_MTrk (GstMidiParse * midiparse, guint8 * data, guint size)
{
GstMidiTrack *track;
GstClockTime duration;
/* ignore excess tracks */
if (midiparse->track_count >= midiparse->ntracks)
return TRUE;
track = g_slice_new (GstMidiTrack);
track->data = data;
track->size = size;
reset_track (track, midiparse);
midiparse->tracks = g_list_append (midiparse->tracks, track);
midiparse->track_count++;
/* now loop over all events and calculate the duration */
while (!track->eot) {
handle_next_event (midiparse, track, NULL, NULL);
}
duration = gst_util_uint64_scale (track->pulse,
1000 * midiparse->tempo, midiparse->division);
GST_DEBUG_OBJECT (midiparse, "duration %" GST_TIME_FORMAT,
GST_TIME_ARGS (duration));
if (duration > midiparse->segment.duration)
midiparse->segment.duration = duration;
reset_track (track, midiparse);
return TRUE;
}
static gboolean
find_midi_chunk (GstMidiParse * midiparse, guint8 * data, guint size,
guint * offset, guint * length)
{
guint32 type;
*length = 0;
if (size < 8)
goto short_chunk;
type = GST_STR_FOURCC (data);
if (type == GST_MAKE_FOURCC ('R', 'I', 'F', 'F')) {
guint32 riff_len;
GST_DEBUG_OBJECT (midiparse, "found RIFF");
if (size < 12)
goto short_chunk;
if (GST_STR_FOURCC (data + 8) != GST_MAKE_FOURCC ('R', 'M', 'I', 'D'))
goto invalid_format;
riff_len = GST_READ_UINT32_LE (data + 4);
if (size < riff_len)
goto short_chunk;
data += 12;
size -= 12;
*offset = 12;
GST_DEBUG_OBJECT (midiparse, "found RIFF RMID of size %u", riff_len);
while (TRUE) {
guint32 chunk_type;
guint32 chunk_len;
if (riff_len < 8)
goto short_chunk;
chunk_type = GST_STR_FOURCC (data);
chunk_len = GST_READ_UINT32_LE (data + 4);
riff_len -= 8;
if (riff_len < chunk_len)
goto short_chunk;
data += 8;
size -= 8;
*offset += 8;
riff_len -= chunk_len;
if (chunk_type == GST_MAKE_FOURCC ('d', 'a', 't', 'a')) {
*length = chunk_len;
break;
}
data += chunk_len;
size -= chunk_len;
}
} else {
*offset = 0;
*length = size;
}
return TRUE;
/* ERRORS */
short_chunk:
{
GST_LOG_OBJECT (midiparse, "not enough data %u < %u", *length + 8, size);
return FALSE;
}
invalid_format:
{
GST_ERROR_OBJECT (midiparse, "invalid format");
return FALSE;
}
}
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", size, length + 8);
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, offset, length;
GstEvent *event;
gchar *stream_id;
GST_DEBUG_OBJECT (midiparse, "Parsing song");
gst_segment_init (&midiparse->segment, GST_FORMAT_TIME);
midiparse->segment.duration = 0;
midiparse->pulse = 0;
size = gst_adapter_available (midiparse->adapter);
data = gst_adapter_take (midiparse->adapter, size);
midiparse->data = data;
midiparse->tempo = DEFAULT_TEMPO;
if (!find_midi_chunk (midiparse, data, size, &offset, &length))
goto invalid_format;
while (length) {
guint consumed;
consumed = gst_midi_parse_chunk (midiparse, &data[offset], length);
if (consumed == 0)
goto short_file;
offset += consumed;
length -= consumed;
}
GST_DEBUG_OBJECT (midiparse, "song duration %" GST_TIME_FORMAT,
GST_TIME_ARGS (midiparse->segment.duration));
stream_id =
gst_pad_create_stream_id (midiparse->srcpad, GST_ELEMENT_CAST (midiparse),
NULL);
event =
gst_pad_get_sticky_event (midiparse->sinkpad, GST_EVENT_STREAM_START, 0);
if (event) {
if (gst_event_parse_group_id (event, &midiparse->group_id))
midiparse->have_group_id = TRUE;
else
midiparse->have_group_id = FALSE;
gst_event_unref (event);
} else if (!midiparse->have_group_id) {
midiparse->have_group_id = TRUE;
midiparse->group_id = gst_util_group_id_next ();
}
event = gst_event_new_stream_start (stream_id);
if (midiparse->have_group_id)
gst_event_set_group_id (event, midiparse->group_id);
gst_pad_push_event (midiparse->srcpad, event);
g_free (stream_id);
outcaps = gst_pad_get_pad_template_caps (midiparse->srcpad);
gst_pad_set_caps (midiparse->srcpad, outcaps);
gst_caps_unref (outcaps);
midiparse->segment_pending = TRUE;
midiparse->discont = TRUE;
GST_DEBUG_OBJECT (midiparse, "Parsing song done");
return GST_FLOW_OK;
/* ERRORS */
short_file:
{
GST_ERROR_OBJECT (midiparse, "not enough data");
return GST_FLOW_ERROR;
}
invalid_format:
{
GST_ERROR_OBJECT (midiparse, "invalid format");
return GST_FLOW_ERROR;
}
}
static GstFlowReturn
play_push_func (GstMidiParse * midiparse, GstMidiTrack * track,
guint8 event, guint8 * data, guint length, gpointer user_data)
{
GstBuffer *outbuf;
GstMapInfo info;
GstClockTime position;
outbuf = gst_buffer_new_allocate (NULL, length + 1, NULL);
gst_buffer_map (outbuf, &info, GST_MAP_WRITE);
info.data[0] = event;
if (length)
memcpy (&info.data[1], data, length);
gst_buffer_unmap (outbuf, &info);
position = midiparse->segment.position;
GST_BUFFER_PTS (outbuf) = position;
GST_BUFFER_DTS (outbuf) = position;
GST_DEBUG_OBJECT (midiparse, "pushing %" GST_TIME_FORMAT,
GST_TIME_ARGS (position));
if (midiparse->discont) {
GST_BUFFER_FLAG_SET (outbuf, GST_BUFFER_FLAG_DISCONT);
midiparse->discont = FALSE;
}
return gst_pad_push (midiparse->srcpad, outbuf);
}
static GstFlowReturn
gst_midi_parse_do_play (GstMidiParse * midiparse)
{
GstFlowReturn res;
GList *walk;
guint64 pulse, next_pulse = G_MAXUINT64;
GstClockTime position, next_position;
guint64 tick;
pulse = midiparse->pulse;
position = midiparse->segment.position;
if (midiparse->segment_pending) {
gst_pad_push_event (midiparse->srcpad,
gst_event_new_segment (&midiparse->segment));
midiparse->segment_pending = FALSE;
}
GST_DEBUG_OBJECT (midiparse, "pulse %" G_GUINT64_FORMAT ", position %"
GST_TIME_FORMAT, pulse, GST_TIME_ARGS (position));
for (walk = midiparse->tracks; walk; walk = g_list_next (walk)) {
GstMidiTrack *track = walk->data;
while (!track->eot && track->pulse == pulse) {
res = handle_next_event (midiparse, track, play_push_func, NULL);
if (res != GST_FLOW_OK)
goto error;
}
if (!track->eot && track->pulse < next_pulse)
next_pulse = track->pulse;
}
if (next_pulse == G_MAXUINT64)
goto eos;
tick = position / (10 * GST_MSECOND);
GST_DEBUG_OBJECT (midiparse, "current tick %" G_GUINT64_FORMAT, tick);
next_position = gst_util_uint64_scale (next_pulse,
1000 * midiparse->tempo, midiparse->division);
GST_DEBUG_OBJECT (midiparse, "next position %" GST_TIME_FORMAT,
GST_TIME_ARGS (next_position));
/* send 10ms ticks to advance the downstream element */
while (TRUE) {
/* get position of next tick */
position = ++tick * (10 * GST_MSECOND);
GST_DEBUG_OBJECT (midiparse, "tick %" G_GUINT64_FORMAT
", position %" GST_TIME_FORMAT, tick, GST_TIME_ARGS (position));
if (position >= next_position)
break;
midiparse->segment.position = position;
res = play_push_func (midiparse, NULL, 0xf9, NULL, 0, NULL);
if (res != GST_FLOW_OK)
goto error;
}
midiparse->pulse = next_pulse;
midiparse->segment.position = next_position;
return GST_FLOW_OK;
/* ERRORS */
eos:
{
GST_DEBUG_OBJECT (midiparse, "we are EOS");
return GST_FLOW_EOS;
}
error:
{
GST_DEBUG_OBJECT (midiparse, "have flow result %s",
gst_flow_get_name (res));
return res;
}
}
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;
case GST_EVENT_CAPS:
case GST_EVENT_STREAM_START:
case GST_EVENT_SEGMENT:
res = TRUE;
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_FLOW_ERROR (midiparse, ret);
gst_pad_push_event (midiparse->srcpad, event);
}
}
}
static void
free_track (GstMidiTrack * track, GstMidiParse * midiparse)
{
g_slice_free (GstMidiTrack, track);
}
static void
gst_midi_parse_reset (GstMidiParse * midiparse)
{
gst_adapter_clear (midiparse->adapter);
g_free (midiparse->data);
midiparse->data = NULL;
g_list_foreach (midiparse->tracks, (GFunc) free_track, midiparse);
g_list_free (midiparse->tracks);
midiparse->tracks = NULL;
midiparse->track_count = 0;
midiparse->have_group_id = FALSE;
midiparse->group_id = G_MAXUINT;
}
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;
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_midi_parse_reset (midiparse);
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;
}
}