/* GStreamer * Copyright (C) <2011> Stefan Kost <ensonic@users.sf.net> * * gstspectrascope.c: frequency spectrum scope * * 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-spectrascope * @see_also: goom * * Spectrascope is a simple spectrum visualisation element. It renders the * frequency spectrum as a series of bars. * * <refsect2> * <title>Example launch line</title> * |[ * gst-launch-1.0 audiotestsrc ! audioconvert ! spectrascope ! ximagesink * ]| * </refsect2> */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include <stdlib.h> #include "gstspectrascope.h" #if G_BYTE_ORDER == G_BIG_ENDIAN #define RGB_ORDER "xRGB" #else #define RGB_ORDER "BGRx" #endif static GstStaticPadTemplate gst_spectra_scope_src_template = GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC, GST_PAD_ALWAYS, GST_STATIC_CAPS (GST_VIDEO_CAPS_MAKE (RGB_ORDER)) ); static GstStaticPadTemplate gst_spectra_scope_sink_template = GST_STATIC_PAD_TEMPLATE ("sink", GST_PAD_SINK, GST_PAD_ALWAYS, GST_STATIC_CAPS ("audio/x-raw, " "format = (string) " GST_AUDIO_NE (S16) ", " "layout = (string) interleaved, " "rate = (int) [ 8000, 96000 ], " "channels = (int) 2, " "channel-mask = (bitmask) 0x3") ); GST_DEBUG_CATEGORY_STATIC (spectra_scope_debug); #define GST_CAT_DEFAULT spectra_scope_debug static void gst_spectra_scope_finalize (GObject * object); static gboolean gst_spectra_scope_setup (GstAudioVisualizer * scope); static gboolean gst_spectra_scope_render (GstAudioVisualizer * scope, GstBuffer * audio, GstVideoFrame * video); G_DEFINE_TYPE (GstSpectraScope, gst_spectra_scope, GST_TYPE_AUDIO_VISUALIZER); static void gst_spectra_scope_class_init (GstSpectraScopeClass * g_class) { GObjectClass *gobject_class = (GObjectClass *) g_class; GstElementClass *element_class = (GstElementClass *) g_class; GstAudioVisualizerClass *scope_class = (GstAudioVisualizerClass *) g_class; gobject_class->finalize = gst_spectra_scope_finalize; gst_element_class_set_static_metadata (element_class, "Frequency spectrum scope", "Visualization", "Simple frequency spectrum scope", "Stefan Kost <ensonic@users.sf.net>"); gst_element_class_add_static_pad_template (element_class, &gst_spectra_scope_src_template); gst_element_class_add_static_pad_template (element_class, &gst_spectra_scope_sink_template); scope_class->setup = GST_DEBUG_FUNCPTR (gst_spectra_scope_setup); scope_class->render = GST_DEBUG_FUNCPTR (gst_spectra_scope_render); } static void gst_spectra_scope_init (GstSpectraScope * scope) { /* do nothing */ } static void gst_spectra_scope_finalize (GObject * object) { GstSpectraScope *scope = GST_SPECTRA_SCOPE (object); if (scope->fft_ctx) { gst_fft_s16_free (scope->fft_ctx); scope->fft_ctx = NULL; } if (scope->freq_data) { g_free (scope->freq_data); scope->freq_data = NULL; } G_OBJECT_CLASS (gst_spectra_scope_parent_class)->finalize (object); } static gboolean gst_spectra_scope_setup (GstAudioVisualizer * bscope) { GstSpectraScope *scope = GST_SPECTRA_SCOPE (bscope); guint num_freq = GST_VIDEO_INFO_WIDTH (&bscope->vinfo) + 1; if (scope->fft_ctx) gst_fft_s16_free (scope->fft_ctx); g_free (scope->freq_data); /* we'd need this amount of samples per render() call */ bscope->req_spf = num_freq * 2 - 2; scope->fft_ctx = gst_fft_s16_new (bscope->req_spf, FALSE); scope->freq_data = g_new (GstFFTS16Complex, num_freq); return TRUE; } static inline void add_pixel (guint32 * _p, guint32 _c) { guint8 *p = (guint8 *) _p; guint8 *c = (guint8 *) & _c; if (p[0] < 255 - c[0]) p[0] += c[0]; else p[0] = 255; if (p[1] < 255 - c[1]) p[1] += c[1]; else p[1] = 255; if (p[2] < 255 - c[2]) p[2] += c[2]; else p[2] = 255; if (p[3] < 255 - c[3]) p[3] += c[3]; else p[3] = 255; } static gboolean gst_spectra_scope_render (GstAudioVisualizer * bscope, GstBuffer * audio, GstVideoFrame * video) { GstSpectraScope *scope = GST_SPECTRA_SCOPE (bscope); gint16 *mono_adata; GstFFTS16Complex *fdata = scope->freq_data; guint x, y, off, l; guint w = GST_VIDEO_INFO_WIDTH (&bscope->vinfo); guint h = GST_VIDEO_INFO_HEIGHT (&bscope->vinfo) - 1; gfloat fr, fi; GstMapInfo amap; guint32 *vdata; gint channels; gst_buffer_map (audio, &amap, GST_MAP_READ); vdata = (guint32 *) GST_VIDEO_FRAME_PLANE_DATA (video, 0); channels = GST_AUDIO_INFO_CHANNELS (&bscope->ainfo); mono_adata = (gint16 *) g_memdup (amap.data, amap.size); if (channels > 1) { guint ch = channels; guint num_samples = amap.size / (ch * sizeof (gint16)); guint i, c, v, s = 0; /* deinterleave and mixdown adata */ for (i = 0; i < num_samples; i++) { v = 0; for (c = 0; c < ch; c++) { v += mono_adata[s++]; } mono_adata[i] = v / ch; } } /* run fft */ gst_fft_s16_window (scope->fft_ctx, mono_adata, GST_FFT_WINDOW_HAMMING); gst_fft_s16_fft (scope->fft_ctx, mono_adata, fdata); g_free (mono_adata); /* draw lines */ for (x = 0; x < w; x++) { /* figure out the range so that we don't need to clip, * or even better do a log mapping? */ fr = (gfloat) fdata[1 + x].r / 512.0; fi = (gfloat) fdata[1 + x].i / 512.0; y = (guint) (h * sqrt (fr * fr + fi * fi)); if (y > h) y = h; y = h - y; off = (y * w) + x; vdata[off] = 0x00FFFFFF; for (l = y; l < h; l++) { off += w; add_pixel (&vdata[off], 0x007F7F7F); } /* ensure bottom line is full bright (especially in move-up mode) */ add_pixel (&vdata[off], 0x007F7F7F); } gst_buffer_unmap (audio, &amap); return TRUE; } gboolean gst_spectra_scope_plugin_init (GstPlugin * plugin) { GST_DEBUG_CATEGORY_INIT (spectra_scope_debug, "spectrascope", 0, "spectrascope"); return gst_element_register (plugin, "spectrascope", GST_RANK_NONE, GST_TYPE_SPECTRA_SCOPE); }