Add song fingerprinting and tracking

Fixes #296

src/engine/chromaprinter.cpp

@@ -0,0 +1,227 @@
+/*
+ * Strawberry Music Player
+ * This file was part of Clementine.
+ * Copyright 2012, David Sansome <me@davidsansome.com>
+ * Copyright 2019-2021, Jonas Kvinge <jonas@jkvinge.net>
+ *
+ * Strawberry is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Strawberry 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "config.h"
+
+#include <glib-object.h>
+#include <cstdint>
+#include <cstdlib>
+#include <cstring>
+#include <sys/types.h>
+#include <chromaprint.h>
+#include <gst/gst.h>
+
+#include <QtGlobal>
+#include <QCoreApplication>
+#include <QThread>
+#include <QIODevice>
+#include <QBuffer>
+#include <QByteArray>
+#include <QString>
+#include <QElapsedTimer>
+#include <QtDebug>
+
+#include "chromaprinter.h"
+#include "core/logging.h"
+#include "core/signalchecker.h"
+
+#ifndef u_int32_t
+typedef unsigned int u_int32_t;
+#endif
+
+static const int kDecodeRate = 11025;
+static const int kDecodeChannels = 1;
+static const int kPlayLengthSecs = 30;
+static const int kTimeoutSecs = 10;
+
+Chromaprinter::Chromaprinter(const QString &filename)
+    : filename_(filename),
+      convert_element_(nullptr) {}
+
+GstElement *Chromaprinter::CreateElement(const QString &factory_name, GstElement *bin) {
+
+  GstElement *ret = gst_element_factory_make( factory_name.toLatin1().constData(), factory_name.toLatin1().constData());
+
+  if (ret && bin) gst_bin_add(GST_BIN(bin), ret);
+
+  if (!ret) {
+    qLog(Warning) << "Couldn't create the gstreamer element" << factory_name;
+  }
+
+  return ret;
+
+}
+
+QString Chromaprinter::CreateFingerprint() {
+
+  Q_ASSERT(QThread::currentThread() != qApp->thread());
+
+  buffer_.open(QIODevice::WriteOnly);
+
+  GstElement *pipeline = gst_pipeline_new("pipeline");
+  GstElement *src = CreateElement("filesrc", pipeline);
+  GstElement *decode = CreateElement("decodebin", pipeline);
+  GstElement *convert = CreateElement("audioconvert", pipeline);
+  GstElement *resample = CreateElement("audioresample", pipeline);
+  GstElement *sink = CreateElement("appsink", pipeline);
+
+  if (!src || !decode || !convert || !resample || !sink) {
+    return QString();
+  }
+
+  convert_element_ = convert;
+
+  // Connect the elements
+  gst_element_link_many(src, decode, nullptr);
+  gst_element_link_many(convert, resample, nullptr);
+
+  // Chromaprint expects mono 16-bit ints at a sample rate of 11025Hz.
+  GstCaps *caps = gst_caps_new_simple(
+      "audio/x-raw",
+      "format", G_TYPE_STRING, "S16LE",
+      "channels", G_TYPE_INT, kDecodeChannels,
+      "rate", G_TYPE_INT, kDecodeRate,
+      nullptr);
+  gst_element_link_filtered(resample, sink, caps);
+  gst_caps_unref(caps);
+
+  GstAppSinkCallbacks callbacks;
+  memset(&callbacks, 0, sizeof(callbacks));
+  callbacks.new_sample = NewBufferCallback;
+  gst_app_sink_set_callbacks(reinterpret_cast<GstAppSink*>(sink), &callbacks, this, nullptr);
+  g_object_set(G_OBJECT(sink), "sync", FALSE, nullptr);
+  g_object_set(G_OBJECT(sink), "emit-signals", TRUE, nullptr);
+
+  // Set the filename
+  g_object_set(src, "location", filename_.toUtf8().constData(), nullptr);
+
+  // Connect signals
+  GstBus *bus = gst_pipeline_get_bus(GST_PIPELINE(pipeline));
+  CHECKED_GCONNECT(decode, "pad-added", &NewPadCallback, this);
+
+  // Play only first x seconds
+  gst_element_set_state(pipeline, GST_STATE_PAUSED);
+  // wait for state change before seeking
+  gst_element_get_state(pipeline, nullptr, nullptr, kTimeoutSecs * GST_SECOND);
+  gst_element_seek(pipeline, 1.0, GST_FORMAT_TIME, GST_SEEK_FLAG_FLUSH, GST_SEEK_TYPE_SET, 0 * GST_SECOND, GST_SEEK_TYPE_SET, kPlayLengthSecs * GST_SECOND);
+
+  QElapsedTimer time;
+  time.start();
+
+  // Start playing
+  gst_element_set_state(pipeline, GST_STATE_PLAYING);
+
+  // Wait until EOS or error
+  GstMessage *msg = gst_bus_timed_pop_filtered(bus, kTimeoutSecs * GST_SECOND, static_cast<GstMessageType>(GST_MESSAGE_EOS | GST_MESSAGE_ERROR));
+  if (msg != nullptr) {
+    if (msg->type == GST_MESSAGE_ERROR) {
+      // Report error
+      GError *error = nullptr;
+      gchar *debugs = nullptr;
+
+      gst_message_parse_error(msg, &error, &debugs);
+      QString message = QString::fromLocal8Bit(error->message);
+
+      g_error_free(error);
+      free(debugs);
+
+      qLog(Debug) << "Error processing" << filename_ << ":" << message;
+    }
+    gst_message_unref(msg);
+  }
+
+  int decode_time = time.restart();
+
+  buffer_.close();
+
+  // Generate fingerprint from recorded buffer data
+  QByteArray data = buffer_.data();
+
+  ChromaprintContext *chromaprint = chromaprint_new(CHROMAPRINT_ALGORITHM_DEFAULT);
+  chromaprint_start(chromaprint, kDecodeRate, kDecodeChannels);
+  chromaprint_feed(chromaprint, reinterpret_cast<int16_t*>(data.data()), static_cast<int>(data.size() / 2));
+  chromaprint_finish(chromaprint);
+
+  u_int32_t *fprint = nullptr;
+  int size = 0;
+  int ret = chromaprint_get_raw_fingerprint(chromaprint, &fprint, &size);
+  QByteArray fingerprint;
+  if (ret == 1) {
+
+    char *encoded = nullptr;
+    int encoded_size = 0;
+    chromaprint_encode_fingerprint(fprint, size, CHROMAPRINT_ALGORITHM_DEFAULT, &encoded, &encoded_size, 1);
+
+    fingerprint.append(reinterpret_cast<char*>(encoded), encoded_size);
+
+    chromaprint_dealloc(fprint);
+    chromaprint_dealloc(encoded);
+  }
+  chromaprint_free(chromaprint);
+  int codegen_time = time.elapsed();
+
+  qLog(Debug) << "Decode time:" << decode_time << "Codegen time:" << codegen_time;
+
+  // Cleanup
+  callbacks.new_sample = nullptr;
+  gst_object_unref(bus);
+  gst_element_set_state(pipeline, GST_STATE_NULL);
+  gst_object_unref(pipeline);
+
+  return fingerprint;
+
+}
+
+void Chromaprinter::NewPadCallback(GstElement*, GstPad *pad, gpointer data) {
+
+  Chromaprinter *instance = reinterpret_cast<Chromaprinter*>(data);
+  GstPad *const audiopad = gst_element_get_static_pad(instance->convert_element_, "sink");
+
+  if (GST_PAD_IS_LINKED(audiopad)) {
+    qLog(Warning) << "audiopad is already linked, unlinking old pad";
+    gst_pad_unlink(audiopad, GST_PAD_PEER(audiopad));
+  }
+
+  gst_pad_link(pad, audiopad);
+  gst_object_unref(audiopad);
+
+}
+
+GstFlowReturn Chromaprinter::NewBufferCallback(GstAppSink *app_sink, gpointer self) {
+
+  Chromaprinter *me = reinterpret_cast<Chromaprinter*>(self);
+
+  GstSample *sample = gst_app_sink_pull_sample(app_sink);
+  if (!sample) return GST_FLOW_ERROR;
+  GstBuffer *buffer = gst_sample_get_buffer(sample);
+  if (buffer) {
+    GstMapInfo map;
+    if (gst_buffer_map(buffer, &map, GST_MAP_READ)) {
+      me->buffer_.write(reinterpret_cast<const char*>(map.data), map.size);
+      gst_buffer_unmap(buffer, &map);
+    }
+  }
+  gst_sample_unref(sample);
+
+  return GST_FLOW_OK;
+
+}
+