1 /*
2 * GStreamer
3 * Copyright (C) 2007 Sebastian Dröge <slomo@circular-chaos.org>
4 * Copyright (C) 2006 Stefan Kost <ensonic@users.sf.net>
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Library General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Library General Public License for more details.
15 *
16 * You should have received a copy of the GNU Library General Public
17 * License along with this library; if not, write to the
18 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
19 * Boston, MA 02110-1301, USA.
20 */
21
22 /**
23 * SECTION:element-audioinvert
24 *
25 * Swaps upper and lower half of audio samples. Mixing an inverted sample on top of
26 * the original with a slight delay can produce effects that sound like resonance.
27 * Creating a stereo sample from a mono source, with one channel inverted produces wide-stereo sounds.
28 *
29 * <refsect2>
30 * <title>Example launch line</title>
31 * |[
32 * gst-launch-1.0 audiotestsrc wave=saw ! audioinvert degree=0.4 ! alsasink
33 * gst-launch-1.0 filesrc location="melo1.ogg" ! oggdemux ! vorbisdec ! audioconvert ! audioinvert degree=0.4 ! alsasink
34 * gst-launch-1.0 audiotestsrc wave=saw ! audioconvert ! audioinvert degree=0.4 ! audioconvert ! alsasink
35 * ]|
36 * </refsect2>
37 */
38
39 #ifdef HAVE_CONFIG_H
40 #include "config.h"
41 #endif
42
43 #include <gst/gst.h>
44 #include <gst/base/gstbasetransform.h>
45 #include <gst/audio/audio.h>
46 #include <gst/audio/gstaudiofilter.h>
47
48 #include "audioinvert.h"
49
50 #define GST_CAT_DEFAULT gst_audio_invert_debug
51 GST_DEBUG_CATEGORY_STATIC (GST_CAT_DEFAULT);
52
53 /* Filter signals and args */
54 enum
55 {
56 /* FILL ME */
57 LAST_SIGNAL
58 };
59
60 enum
61 {
62 PROP_0,
63 PROP_DEGREE
64 };
65
66 #define ALLOWED_CAPS \
67 "audio/x-raw," \
68 " format=(string) {"GST_AUDIO_NE(S16)","GST_AUDIO_NE(F32)"}," \
69 " rate=(int)[1,MAX]," \
70 " channels=(int)[1,MAX]," \
71 " layout=(string) {interleaved, non-interleaved}"
72
73 G_DEFINE_TYPE (GstAudioInvert, gst_audio_invert, GST_TYPE_AUDIO_FILTER);
74
75 static void gst_audio_invert_set_property (GObject * object, guint prop_id,
76 const GValue * value, GParamSpec * pspec);
77 static void gst_audio_invert_get_property (GObject * object, guint prop_id,
78 GValue * value, GParamSpec * pspec);
79
80 static gboolean gst_audio_invert_setup (GstAudioFilter * filter,
81 const GstAudioInfo * info);
82 static GstFlowReturn gst_audio_invert_transform_ip (GstBaseTransform * base,
83 GstBuffer * buf);
84
85 static void gst_audio_invert_transform_int (GstAudioInvert * filter,
86 gint16 * data, guint num_samples);
87 static void gst_audio_invert_transform_float (GstAudioInvert * filter,
88 gfloat * data, guint num_samples);
89
90 /* GObject vmethod implementations */
91
92 static void
gst_audio_invert_class_init(GstAudioInvertClass * klass)93 gst_audio_invert_class_init (GstAudioInvertClass * klass)
94 {
95 GObjectClass *gobject_class;
96 GstElementClass *gstelement_class;
97 GstCaps *caps;
98
99 GST_DEBUG_CATEGORY_INIT (gst_audio_invert_debug, "audioinvert", 0,
100 "audioinvert element");
101
102 gobject_class = (GObjectClass *) klass;
103 gstelement_class = (GstElementClass *) klass;
104
105 gobject_class->set_property = gst_audio_invert_set_property;
106 gobject_class->get_property = gst_audio_invert_get_property;
107
108 g_object_class_install_property (gobject_class, PROP_DEGREE,
109 g_param_spec_float ("degree", "Degree",
110 "Degree of inversion", 0.0, 1.0,
111 0.0,
112 G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
113
114 gst_element_class_set_static_metadata (gstelement_class, "Audio inversion",
115 "Filter/Effect/Audio",
116 "Swaps upper and lower half of audio samples",
117 "Sebastian Dröge <slomo@circular-chaos.org>");
118
119 caps = gst_caps_from_string (ALLOWED_CAPS);
120 gst_audio_filter_class_add_pad_templates (GST_AUDIO_FILTER_CLASS (klass),
121 caps);
122 gst_caps_unref (caps);
123
124 GST_BASE_TRANSFORM_CLASS (klass)->transform_ip =
125 GST_DEBUG_FUNCPTR (gst_audio_invert_transform_ip);
126 GST_BASE_TRANSFORM_CLASS (klass)->transform_ip_on_passthrough = FALSE;
127
128 GST_AUDIO_FILTER_CLASS (klass)->setup =
129 GST_DEBUG_FUNCPTR (gst_audio_invert_setup);
130 }
131
132 static void
gst_audio_invert_init(GstAudioInvert * filter)133 gst_audio_invert_init (GstAudioInvert * filter)
134 {
135 filter->degree = 0.0;
136 gst_base_transform_set_in_place (GST_BASE_TRANSFORM (filter), TRUE);
137 gst_base_transform_set_gap_aware (GST_BASE_TRANSFORM (filter), TRUE);
138 }
139
140 static void
gst_audio_invert_set_property(GObject * object,guint prop_id,const GValue * value,GParamSpec * pspec)141 gst_audio_invert_set_property (GObject * object, guint prop_id,
142 const GValue * value, GParamSpec * pspec)
143 {
144 GstAudioInvert *filter = GST_AUDIO_INVERT (object);
145
146 switch (prop_id) {
147 case PROP_DEGREE:
148 filter->degree = g_value_get_float (value);
149 gst_base_transform_set_passthrough (GST_BASE_TRANSFORM (filter),
150 filter->degree == 0.0);
151 break;
152 default:
153 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
154 break;
155 }
156 }
157
158 static void
gst_audio_invert_get_property(GObject * object,guint prop_id,GValue * value,GParamSpec * pspec)159 gst_audio_invert_get_property (GObject * object, guint prop_id,
160 GValue * value, GParamSpec * pspec)
161 {
162 GstAudioInvert *filter = GST_AUDIO_INVERT (object);
163
164 switch (prop_id) {
165 case PROP_DEGREE:
166 g_value_set_float (value, filter->degree);
167 break;
168 default:
169 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
170 break;
171 }
172 }
173
174 /* GstAudioFilter vmethod implementations */
175
176 static gboolean
gst_audio_invert_setup(GstAudioFilter * base,const GstAudioInfo * info)177 gst_audio_invert_setup (GstAudioFilter * base, const GstAudioInfo * info)
178 {
179 GstAudioInvert *filter = GST_AUDIO_INVERT (base);
180 gboolean ret = TRUE;
181
182 switch (GST_AUDIO_INFO_FORMAT (info)) {
183 case GST_AUDIO_FORMAT_S16:
184 filter->process = (GstAudioInvertProcessFunc)
185 gst_audio_invert_transform_int;
186 break;
187 case GST_AUDIO_FORMAT_F32:
188 filter->process = (GstAudioInvertProcessFunc)
189 gst_audio_invert_transform_float;
190 break;
191 default:
192 ret = FALSE;
193 break;
194 }
195 return ret;
196 }
197
198 static void
gst_audio_invert_transform_int(GstAudioInvert * filter,gint16 * data,guint num_samples)199 gst_audio_invert_transform_int (GstAudioInvert * filter,
200 gint16 * data, guint num_samples)
201 {
202 gint i;
203 gfloat dry = 1.0 - filter->degree;
204 glong val;
205
206 for (i = 0; i < num_samples; i++) {
207 val = (*data) * dry + (-1 - (*data)) * filter->degree;
208 *data++ = (gint16) CLAMP (val, G_MININT16, G_MAXINT16);
209 }
210 }
211
212 static void
gst_audio_invert_transform_float(GstAudioInvert * filter,gfloat * data,guint num_samples)213 gst_audio_invert_transform_float (GstAudioInvert * filter,
214 gfloat * data, guint num_samples)
215 {
216 gint i;
217 gfloat dry = 1.0 - filter->degree;
218 glong val;
219
220 for (i = 0; i < num_samples; i++) {
221 val = (*data) * dry - (*data) * filter->degree;
222 *data++ = val;
223 }
224 }
225
226 /* GstBaseTransform vmethod implementations */
227 static GstFlowReturn
gst_audio_invert_transform_ip(GstBaseTransform * base,GstBuffer * buf)228 gst_audio_invert_transform_ip (GstBaseTransform * base, GstBuffer * buf)
229 {
230 GstAudioInvert *filter = GST_AUDIO_INVERT (base);
231 guint num_samples;
232 GstClockTime timestamp, stream_time;
233 GstMapInfo map;
234
235 timestamp = GST_BUFFER_TIMESTAMP (buf);
236 stream_time =
237 gst_segment_to_stream_time (&base->segment, GST_FORMAT_TIME, timestamp);
238
239 GST_DEBUG_OBJECT (filter, "sync to %" GST_TIME_FORMAT,
240 GST_TIME_ARGS (timestamp));
241
242 if (GST_CLOCK_TIME_IS_VALID (stream_time))
243 gst_object_sync_values (GST_OBJECT (filter), stream_time);
244
245 if (G_UNLIKELY (GST_BUFFER_FLAG_IS_SET (buf, GST_BUFFER_FLAG_GAP)))
246 return GST_FLOW_OK;
247
248 gst_buffer_map (buf, &map, GST_MAP_READWRITE);
249 num_samples = map.size / GST_AUDIO_FILTER_BPS (filter);
250
251 filter->process (filter, map.data, num_samples);
252
253 gst_buffer_unmap (buf, &map);
254
255 return GST_FLOW_OK;
256 }
257