/* GStreamer * Copyright (C) 1999 Erik Walthinsen * PCM - A-Law conversion * Copyright (C) 2000 by Abramo Bagnara * * 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 2.1 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., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include "alaw-decode.h" extern GstPadTemplate *alawdec_src_template, *alawdec_sink_template; /* elementfactory information */ static GstElementDetails alawdec_details = { "A Law to PCM conversion", "Codec/Decoder/Audio", "Convert 8bit A law to 16bit PCM", "Zaheer Merali " }; /* Stereo signals and args */ enum { /* FILL ME */ LAST_SIGNAL }; enum { ARG_0 }; static void gst_alawdec_class_init (GstALawDecClass * klass); static void gst_alawdec_base_init (GstALawDecClass * klass); static void gst_alawdec_init (GstALawDec * alawdec); static void gst_alawdec_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec); static void gst_alawdec_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec); static void gst_alawdec_chain (GstPad * pad, GstData * _data); static GstElementClass *parent_class = NULL; /*static guint gst_stereo_signals[LAST_SIGNAL] = { 0 }; */ /* * alaw_to_s16() - Convert an A-law value to 16-bit linear PCM * */ static gint alaw_to_s16 (guint8 a_val) { gint t; gint seg; a_val ^= 0x55; t = a_val & 0x7f; if (t < 16) t = (t << 4) + 8; else { seg = (t >> 4) & 0x07; t = ((t & 0x0f) << 4) + 0x108; t <<= seg - 1; } return ((a_val & 0x80) ? t : -t); } static GstPadLinkReturn alawdec_link (GstPad * pad, const GstCaps * caps) { GstCaps *tempcaps; gint rate, channels; GstStructure *structure; gboolean ret; GstALawDec *alawdec = GST_ALAWDEC (GST_OBJECT_PARENT (pad)); structure = gst_caps_get_structure (caps, 0); ret = gst_structure_get_int (structure, "rate", &rate); ret &= gst_structure_get_int (structure, "channels", &channels); if (!ret) return GST_PAD_LINK_REFUSED; tempcaps = gst_caps_new_simple ("audio/x-raw-int", "depth", G_TYPE_INT, 16, "width", G_TYPE_INT, 16, "signed", G_TYPE_BOOLEAN, TRUE, "endianness", G_TYPE_INT, G_BYTE_ORDER, "rate", G_TYPE_INT, rate, "channels", G_TYPE_INT, channels, NULL); return gst_pad_try_set_caps (alawdec->srcpad, tempcaps); } GType gst_alawdec_get_type (void) { static GType alawdec_type = 0; if (!alawdec_type) { static const GTypeInfo alawdec_info = { sizeof (GstALawDecClass), (GBaseInitFunc) gst_alawdec_base_init, NULL, (GClassInitFunc) gst_alawdec_class_init, NULL, NULL, sizeof (GstALawDec), 0, (GInstanceInitFunc) gst_alawdec_init, }; alawdec_type = g_type_register_static (GST_TYPE_ELEMENT, "GstALawDec", &alawdec_info, 0); } return alawdec_type; } static void gst_alawdec_base_init (GstALawDecClass * klass) { GstElementClass *element_class = GST_ELEMENT_CLASS (klass); gst_element_class_add_pad_template (element_class, alawdec_src_template); gst_element_class_add_pad_template (element_class, alawdec_sink_template); gst_element_class_set_details (element_class, &alawdec_details); } static void gst_alawdec_class_init (GstALawDecClass * klass) { GObjectClass *gobject_class; GstElementClass *gstelement_class; gobject_class = (GObjectClass *) klass; gstelement_class = (GstElementClass *) klass; parent_class = g_type_class_ref (GST_TYPE_ELEMENT); gobject_class->set_property = gst_alawdec_set_property; gobject_class->get_property = gst_alawdec_get_property; } static void gst_alawdec_init (GstALawDec * alawdec) { alawdec->sinkpad = gst_pad_new_from_template (alawdec_sink_template, "sink"); alawdec->srcpad = gst_pad_new_from_template (alawdec_src_template, "src"); gst_pad_set_link_function (alawdec->sinkpad, alawdec_link); gst_element_add_pad (GST_ELEMENT (alawdec), alawdec->sinkpad); gst_pad_set_chain_function (alawdec->sinkpad, gst_alawdec_chain); gst_element_add_pad (GST_ELEMENT (alawdec), alawdec->srcpad); } static void gst_alawdec_chain (GstPad * pad, GstData * _data) { GstBuffer *buf = GST_BUFFER (_data); GstALawDec *alawdec; gint16 *linear_data; guint8 *alaw_data; GstBuffer *outbuf; gint i; g_return_if_fail (pad != NULL); g_return_if_fail (GST_IS_PAD (pad)); g_return_if_fail (buf != NULL); alawdec = GST_ALAWDEC (GST_OBJECT_PARENT (pad)); g_return_if_fail (alawdec != NULL); g_return_if_fail (GST_IS_ALAWDEC (alawdec)); alaw_data = (guint8 *) GST_BUFFER_DATA (buf); outbuf = gst_buffer_new (); GST_BUFFER_DATA (outbuf) = (gchar *) g_new (gint16, GST_BUFFER_SIZE (buf)); GST_BUFFER_SIZE (outbuf) = GST_BUFFER_SIZE (buf) * 2; linear_data = (gint16 *) GST_BUFFER_DATA (outbuf); for (i = 0; i < GST_BUFFER_SIZE (buf); i++) { *linear_data = alaw_to_s16 (*alaw_data); linear_data++; alaw_data++; } gst_buffer_unref (buf); gst_pad_push (alawdec->srcpad, GST_DATA (outbuf)); } static void gst_alawdec_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec) { GstALawDec *alawdec; /* it's not null if we got it, but it might not be ours */ g_return_if_fail (GST_IS_ALAWDEC (object)); alawdec = GST_ALAWDEC (object); switch (prop_id) { default: break; } } static void gst_alawdec_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec) { GstALawDec *alawdec; /* it's not null if we got it, but it might not be ours */ g_return_if_fail (GST_IS_ALAWDEC (object)); alawdec = GST_ALAWDEC (object); switch (prop_id) { default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } }