gstreamer/gst/accurip/gstaccurip.c
2017-04-12 12:57:57 -03:00

369 lines
11 KiB
C

/* GStreamer AccurateRip (TM) audio checksumming element
*
* Copyright (C) 2012 Christophe Fergeau <teuf@gnome.org>
*
* Based on the GStreamer chromaprint audio fingerprinting element
* Copyright (C) 2006 M. Derezynski
* Copyright (C) 2008 Eric Buehl
* Copyright (C) 2008 Sebastian Dröge <slomo@circular-chaos.org>
* Copyright (C) 2011 Lukáš Lalinský <lalinsky@gmail.com>
* Copyright (C) 2012 Collabora Ltd. <tim.muller@collabora.co.uk>
*
* 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.
*/
/*
* Based on the documentation from
* http://forum.dbpoweramp.com/showthread.php?20641-AccurateRip-CRC-Calculation
* and
* http://jonls.dk/2009/10/calculating-accuraterip-checksums/
*/
/**
* SECTION:element-accurip
* @title: accurip
* @short_desc: Computes an AccurateRip CRC
*
* The accurip element calculates a CRC for an audio stream which can be used
* to match the audio stream to a database hosted on
* <ulink url="http://accuraterip.com/">AccurateRip</ulink>. This database
* is used to check for a CD rip accuracy.
*
* ## Example launch line
* |[
* gst-launch-1.0 -m uridecodebin uri=file:///path/to/song.flac ! audioconvert ! accurip ! fakesink
* ]|
*
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "gstaccurip.h"
#define DEFAULT_MAX_DURATION 120
#define PAD_CAPS \
"audio/x-raw, " \
"format = (string) " GST_AUDIO_NE(S16) ", "\
"rate = (int) 44100, " \
"channels = (int) 2"
GST_DEBUG_CATEGORY_STATIC (gst_accurip_debug);
#define GST_CAT_DEFAULT gst_accurip_debug
enum
{
PROP_0,
PROP_FIRST_TRACK,
PROP_LAST_TRACK
};
#define parent_class gst_accurip_parent_class
G_DEFINE_TYPE (GstAccurip, gst_accurip, GST_TYPE_AUDIO_FILTER);
static void gst_accurip_finalize (GObject * object);
static void gst_accurip_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_accurip_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static GstFlowReturn gst_accurip_transform_ip (GstBaseTransform * trans,
GstBuffer * buf);
static gboolean gst_accurip_sink_event (GstBaseTransform * trans,
GstEvent * event);
static void
gst_accurip_class_init (GstAccuripClass * klass)
{
GObjectClass *gobject_class;
GstBaseTransformClass *gstbasetrans_class;
GstCaps *caps;
gobject_class = G_OBJECT_CLASS (klass);
gstbasetrans_class = GST_BASE_TRANSFORM_CLASS (klass);
gobject_class->set_property = gst_accurip_set_property;
gobject_class->get_property = gst_accurip_get_property;
g_object_class_install_property (gobject_class, PROP_FIRST_TRACK,
g_param_spec_boolean ("first-track", "First track",
"Indicate to the CRC calculation algorithm that this is the first track of a set",
FALSE, G_PARAM_READWRITE));
g_object_class_install_property (gobject_class, PROP_LAST_TRACK,
g_param_spec_boolean ("last-track", "Last track",
"Indicate to the CRC calculation algorithm that this is the last track of a set",
FALSE, G_PARAM_READWRITE));
gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_accurip_finalize);
gstbasetrans_class->transform_ip =
GST_DEBUG_FUNCPTR (gst_accurip_transform_ip);
gstbasetrans_class->sink_event = GST_DEBUG_FUNCPTR (gst_accurip_sink_event);
gstbasetrans_class->passthrough_on_same_caps = TRUE;
gst_element_class_set_metadata (GST_ELEMENT_CLASS (klass),
"AccurateRip(TM) CRC element",
"Filter/Analyzer/Audio",
"Computes an AccurateRip CRC", "Christophe Fergeau <teuf@gnome.org>");
caps = gst_caps_from_string (PAD_CAPS);
gst_audio_filter_class_add_pad_templates (GST_AUDIO_FILTER_CLASS (klass),
caps);
gst_caps_unref (caps);
}
static void
ring_free (GstAccurip * accurip)
{
g_free (accurip->crcs_ring);
g_free (accurip->crcs_v2_ring);
accurip->crcs_ring = NULL;
accurip->crcs_v2_ring = NULL;
accurip->ring_samples = 0;
}
static void
gst_accurip_reset (GstAccurip * accurip)
{
if (accurip->num_samples != 0) {
/* Don't reset these values on the NEW_SEGMENT event we get when
* the pipeline starts playing, they may have been set by the
* element user while creating the pipeline
*/
accurip->is_first = FALSE;
accurip->is_last = FALSE;
ring_free (accurip);
}
accurip->crc = 0;
accurip->crc_v2 = 0;
accurip->num_samples = 0;
}
/* We must ignore the first and last 5 CD sectors. A CD sector is worth
* 2352 bytes of audio */
#define IGNORED_SAMPLES_COUNT (2352 * 5 / (2*2))
static void
gst_accurip_emit_tags (GstAccurip * accurip)
{
GstTagList *tags;
if (accurip->num_samples == 0)
return;
if (accurip->is_last) {
guint index;
if (accurip->ring_samples <= IGNORED_SAMPLES_COUNT) {
return;
}
index = accurip->ring_samples - IGNORED_SAMPLES_COUNT;
index %= (IGNORED_SAMPLES_COUNT + 1);
accurip->crc = accurip->crcs_ring[index];
accurip->crc_v2 = accurip->crcs_v2_ring[index];
}
GST_DEBUG_OBJECT (accurip,
"Generating CRC based on %" G_GUINT64_FORMAT " samples",
accurip->num_samples);
tags = gst_tag_list_new (GST_TAG_ACCURIP_CRC, accurip->crc,
GST_TAG_ACCURIP_CRC_V2, accurip->crc_v2, NULL);
GST_DEBUG_OBJECT (accurip, "Computed CRC=%08X and CRCv2=0x%08X \n",
accurip->crc, accurip->crc_v2);
gst_pad_push_event (GST_BASE_TRANSFORM_SRC_PAD (accurip),
gst_event_new_tag (tags));
}
static void
gst_accurip_init (GstAccurip * accurip)
{
gst_base_transform_set_passthrough (GST_BASE_TRANSFORM (accurip), TRUE);
}
static void
gst_accurip_finalize (GObject * object)
{
ring_free (GST_ACCURIP (object));
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static GstFlowReturn
gst_accurip_transform_ip (GstBaseTransform * trans, GstBuffer * buf)
{
GstAccurip *accurip = GST_ACCURIP (trans);
GstAudioFilter *filter = GST_AUDIO_FILTER (trans);
guint32 *data;
GstMapInfo map_info;
guint nsamples;
gint channels;
guint i;
channels = GST_AUDIO_INFO_CHANNELS (&filter->info);
if (G_UNLIKELY (channels != 2))
return GST_FLOW_NOT_NEGOTIATED;
if (!gst_buffer_map (buf, &map_info, GST_MAP_READ))
return GST_FLOW_ERROR;
data = (guint32 *) map_info.data;
nsamples = map_info.size / (channels * 2);
for (i = 0; i < nsamples; i++) {
guint64 mult_sample;
/* the AccurateRip algorithm counts samples starting from 1 instead
* of 0, that's why we start by incrementing the number of samples
* before doing the calculations
*/
accurip->num_samples++;
/* On the first track, we have to ignore the first 5 CD sectors of
* audio data
*/
if (accurip->is_first && accurip->num_samples < IGNORED_SAMPLES_COUNT)
continue;
/* Actual CRC computation is here */
mult_sample = data[i] * accurip->num_samples;
accurip->crc += mult_sample;
accurip->crc_v2 += mult_sample & 0xffffffff;
accurip->crc_v2 += (mult_sample >> 32);
/* On the last track, we've got to ignore the last 5 CD sectors of
* audio data, since we cannot know in advance when the last buffer
* will be, we keep 5 CD sectors samples + 1 in memory so that we
* can rollback to the 'good' value when we reach the end of stream.
* This magic is only needed when the 'track-last' property is set.
*/
if (accurip->is_last) {
guint index = accurip->ring_samples % (IGNORED_SAMPLES_COUNT + 1);
accurip->ring_samples++;
accurip->crcs_ring[index] = accurip->crc;
accurip->crcs_v2_ring[index] = accurip->crc_v2;
}
}
gst_buffer_unmap (buf, &map_info);
return GST_FLOW_OK;
}
static gboolean
gst_accurip_sink_event (GstBaseTransform * trans, GstEvent * event)
{
GstAccurip *accurip = GST_ACCURIP (trans);
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_FLUSH_STOP:
case GST_EVENT_SEGMENT:
GST_DEBUG_OBJECT (trans, "Got %s event, clearing buffer",
GST_EVENT_TYPE_NAME (event));
gst_accurip_emit_tags (accurip);
gst_accurip_reset (accurip);
break;
case GST_EVENT_EOS:
gst_accurip_emit_tags (accurip);
break;
default:
break;
}
return GST_BASE_TRANSFORM_CLASS (parent_class)->sink_event (trans, event);
}
static void
gst_accurip_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstAccurip *accurip = GST_ACCURIP (object);
switch (prop_id) {
case PROP_FIRST_TRACK:
accurip->is_first = g_value_get_boolean (value);
break;
case PROP_LAST_TRACK:
if (accurip->is_last != g_value_get_boolean (value)) {
ring_free (accurip);
}
accurip->is_last = g_value_get_boolean (value);
if (accurip->is_last) {
if (accurip->crcs_ring == NULL) {
accurip->crcs_ring = g_new0 (guint32, IGNORED_SAMPLES_COUNT + 1);
}
if (accurip->crcs_v2_ring == NULL) {
accurip->crcs_v2_ring = g_new0 (guint32, IGNORED_SAMPLES_COUNT + 1);
}
}
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_accurip_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstAccurip *accurip = GST_ACCURIP (object);
switch (prop_id) {
case PROP_FIRST_TRACK:
g_value_set_boolean (value, accurip->is_first);
break;
case PROP_LAST_TRACK:
g_value_set_boolean (value, accurip->is_last);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static gboolean
plugin_init (GstPlugin * plugin)
{
gboolean ret;
GST_DEBUG_CATEGORY_INIT (gst_accurip_debug, "accurip", 0, "accurip element");
ret = gst_element_register (plugin, "accurip", GST_RANK_NONE,
GST_TYPE_ACCURIP);
if (ret) {
gst_tag_register (GST_TAG_ACCURIP_CRC, GST_TAG_FLAG_META,
G_TYPE_UINT, "accurip crc", "AccurateRip(TM) CRC", NULL);
gst_tag_register (GST_TAG_ACCURIP_CRC_V2, GST_TAG_FLAG_META,
G_TYPE_UINT, "accurip crc (v2)", "AccurateRip(TM) CRC (version 2)",
NULL);
}
return ret;
}
GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
GST_VERSION_MINOR,
accurip,
"Computes an AccurateRip CRC",
plugin_init, VERSION, "LGPL", GST_PACKAGE_NAME, GST_PACKAGE_ORIGIN)