--- /dev/null
+/* GStreamer
+ * Copyright (C) 2009 Pioneers of the Inevitable <songbird@songbirdnest.com>
+ *
+ * Authors: Michael Smith <msmith@songbirdnest.com>
+ *
+ * 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., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+/* Based on MS-ADPCM decoder in libsndfile,
+ Copyright (C) 1999-2002 Erik de Castro Lopo <erikd@zip.com.au
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <gst/gst.h>
+#include <gst/base/gstadapter.h>
+
+#define GST_TYPE_ADPCM_DEC \
+ (adpcmdec_get_type ())
+
+#define GST_ADPCM_DEC(obj) \
+ (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_ADPCM_DEC, ADPCMDec))
+
+#define GST_CAT_DEFAULT adpcmdec_debug
+GST_DEBUG_CATEGORY_STATIC (adpcmdec_debug);
+
+static const GstElementDetails adpcmdec_details =
+GST_ELEMENT_DETAILS ("MS-ADPCM decoder",
+ "Codec/Decoder/Audio",
+ "Decode MS AD-PCM audio",
+ "Pioneers of the Inevitable <songbird@songbirdnest.com");
+
+static GstStaticPadTemplate adpcmdec_sink_template =
+GST_STATIC_PAD_TEMPLATE ("sink",
+ GST_PAD_SINK,
+ GST_PAD_ALWAYS,
+ GST_STATIC_CAPS ("audio/x-adpcm, "
+ "layout=(string)microsoft, "
+ "block_align = (int) [64, 8096], "
+ "rate = (int)[ 1, MAX ], " "channels = (int)[1,2]")
+ );
+
+static GstStaticPadTemplate adpcmdec_src_template =
+GST_STATIC_PAD_TEMPLATE ("src",
+ GST_PAD_SRC,
+ GST_PAD_ALWAYS,
+ GST_STATIC_CAPS ("audio/x-raw-int, "
+ "depth = (int)16, "
+ "width = (int)16, "
+ "endianness = (int)" G_STRINGIFY (G_BYTE_ORDER) ", "
+ "signed = (boolean)TRUE, "
+ "channels = (int) [1,2], " "rate = (int)[1, MAX]")
+ );
+
+typedef struct _ADPCMDecClass
+{
+ GstElementClass parent_class;
+} ADPCMDecClass;
+
+typedef struct _ADPCMDec
+{
+ GstElement parent;
+
+ GstPad *sinkpad;
+ GstPad *srcpad;
+
+ GstCaps *output_caps;
+
+ int rate;
+ int channels;
+ int blocksize;
+
+ gboolean is_setup;
+
+ GstClockTime timestamp;
+
+ guint64 out_samples;
+
+ GstAdapter *adapter;
+
+} ADPCMDec;
+
+GST_BOILERPLATE (ADPCMDec, adpcmdec, GstElement, GST_TYPE_ELEMENT);
+static gboolean
+adpcmdec_setup (ADPCMDec * dec)
+{
+ dec->output_caps = gst_caps_new_simple ("audio/x-raw-int",
+ "rate", G_TYPE_INT, dec->rate,
+ "channels", G_TYPE_INT, dec->channels,
+ "width", G_TYPE_INT, 16,
+ "depth", G_TYPE_INT, 16,
+ "endianness", G_TYPE_INT, G_BYTE_ORDER,
+ "signed", G_TYPE_BOOLEAN, TRUE, NULL);
+
+ if (dec->output_caps) {
+ gst_pad_set_caps (dec->srcpad, dec->output_caps);
+ }
+
+ dec->is_setup = TRUE;
+ dec->timestamp = GST_CLOCK_TIME_NONE;
+ dec->adapter = gst_adapter_new ();
+ dec->out_samples = 0;
+
+ return gst_pad_push_event (dec->srcpad, gst_event_new_new_segment (FALSE,
+ 1.0, GST_FORMAT_TIME, 0, -1, 0));
+}
+
+static void
+adpcmdec_teardown (ADPCMDec * dec)
+{
+ if (dec->output_caps) {
+ gst_caps_unref (dec->output_caps);
+ dec->output_caps = NULL;
+ }
+ if (dec->adapter) {
+ g_object_unref (dec->adapter);
+ dec->adapter = NULL;
+ }
+ dec->is_setup = FALSE;
+}
+
+static gboolean
+adpcmdec_sink_setcaps (GstPad * pad, GstCaps * caps)
+{
+ ADPCMDec *dec = (ADPCMDec *) gst_pad_get_parent (pad);
+ GstStructure *structure = gst_caps_get_structure (caps, 0);
+
+ if (!gst_structure_get_int (structure, "block_align", &dec->blocksize))
+ return FALSE;
+ if (!gst_structure_get_int (structure, "rate", &dec->rate))
+ return FALSE;
+ if (!gst_structure_get_int (structure, "channels", &dec->channels))
+ return FALSE;
+
+ if (dec->is_setup)
+ adpcmdec_teardown (dec);
+ gst_object_unref (dec);
+
+ return TRUE;
+}
+
+
+/*=====================================================================
+ * From libsndfile:
+ *
+ * MS ADPCM Block Layout.
+ * ======================
+ * Block is usually 256, 512 or 1024 bytes depending on sample rate.
+ * For a mono file, the block is laid out as follows:
+ * byte purpose
+ * 0 block predictor [0..6]
+ * 1,2 initial idelta (positive)
+ * 3,4 sample 1
+ * 5,6 sample 0
+ * 7..n packed bytecodes
+ *
+ * For a stereo file, the block is laid out as follows:
+ * byte purpose
+ * 0 block predictor [0..6] for left channel
+ * 1 block predictor [0..6] for right channel
+ * 2,3 initial idelta (positive) for left channel
+ * 4,5 initial idelta (positive) for right channel
+ * 6,7 sample 1 for left channel
+ * 8,9 sample 1 for right channel
+ * 10,11 sample 0 for left channel
+ * 12,13 sample 0 for right channel
+ * 14..n packed bytecodes
+ *
+ *=====================================================================
+*/
+static int AdaptationTable[] = {
+ 230, 230, 230, 230, 307, 409, 512, 614,
+ 768, 614, 512, 409, 307, 230, 230, 230
+};
+
+static int AdaptCoeff1[] = {
+ 256, 512, 0, 192, 240, 460, 392
+};
+
+static int AdaptCoeff2[] = {
+ 0, -256, 0, 64, 0, -208, -232
+};
+
+static gint16
+read_sample (guint8 * data)
+{
+ guint16 val = data[0] | (data[1] << 8);
+ return *((gint16 *) & val);
+}
+
+/* Decode a single block of data from 'data', storing 'n_samples' decoded 16 bit
+ samples in 'samples'.
+
+ All buffer lengths have been verified by the caller
+ */
+static gboolean
+adpcmdec_decode_ms_block (ADPCMDec * dec, int n_samples, guint8 * data,
+ gint16 * samples)
+{
+ gint16 pred[2];
+ gint16 idelta[2];
+ int idx; /* Current byte offset in 'data' */
+ int i; /* Current sample index in 'samples' */
+
+ /* Read the block header, verify for sanity */
+ if (dec->channels == 1) {
+ pred[0] = data[0];
+ idelta[0] = read_sample (data + 1);
+ samples[1] = read_sample (data + 3);
+ samples[0] = read_sample (data + 5);
+ idx = 7;
+ i = 2;
+ if (pred[0] < 0 || pred[0] > 6) {
+ GST_WARNING_OBJECT (dec, "Invalid block predictor");
+ return FALSE;
+ }
+ }
+
+ else {
+ pred[0] = data[0];
+ pred[1] = data[1];
+ idelta[0] = read_sample (data + 2);
+ idelta[1] = read_sample (data + 4);
+ samples[2] = read_sample (data + 6);
+ samples[3] = read_sample (data + 8);
+ samples[0] = read_sample (data + 10);
+ samples[1] = read_sample (data + 12);
+ idx = 14;
+ i = 4;
+ if (pred[0] < 0 || pred[0] > 6 || pred[1] < 0 || pred[1] > 6) {
+ GST_WARNING_OBJECT (dec, "Invalid block predictor");
+ return FALSE;
+ }
+ }
+ for (; i < n_samples; i++) {
+ int chan = i % dec->channels;
+ int bytecode;
+ int delta;
+ int current;
+ int predict;
+ if (i % 2 == 0) {
+ bytecode = (data[idx] >> 4) & 0x0F;
+ } else {
+ bytecode = data[idx] & 0x0F;
+ idx++;
+ }
+
+ delta = idelta[chan];
+ idelta[chan] = (AdaptationTable[bytecode] * delta) >> 8;
+ if (idelta[chan] < 16)
+ idelta[chan] = 16;
+
+ /* Bytecode is used above as an index into the table. Below, it's used
+ as a signed 4-bit value; convert appropriately */
+ if (bytecode & 0x8)
+ bytecode -= 0x10;
+
+ predict = ((samples[i - dec->channels] * AdaptCoeff1[pred[chan]]) +
+ (samples[i - 2 * dec->channels] * AdaptCoeff2[pred[chan]])
+ ) >> 8;
+
+ current = (bytecode * delta) + predict;
+
+ /* Clamp to 16 bits, store decoded sample */
+ samples[i] = CLAMP (current, G_MININT16, G_MAXINT16);
+ }
+ return TRUE;
+}
+
+static GstFlowReturn
+adpcmdec_chain (GstPad * pad, GstBuffer * buf)
+{
+ ADPCMDec *dec = (ADPCMDec *) gst_pad_get_parent (pad);
+ GstFlowReturn ret = GST_FLOW_OK;
+ guint8 *data;
+ GstBuffer *outbuf = NULL;
+ GstBuffer *databuf = NULL;
+ int outsize;
+ int samples;
+ gboolean res;
+
+ if (!dec->is_setup)
+ adpcmdec_setup (dec);
+
+ if (dec->timestamp == GST_CLOCK_TIME_NONE)
+ dec->timestamp = GST_BUFFER_TIMESTAMP (buf);
+
+ gst_adapter_push (dec->adapter, buf);
+
+ while (gst_adapter_available (dec->adapter) >= dec->blocksize) {
+ databuf = gst_adapter_take_buffer (dec->adapter, dec->blocksize);
+ data = GST_BUFFER_DATA (databuf);
+
+ /* Each block has a 3 byte header per channel, plus 4 bytes per channel to
+ give two initial sample values per channel. Then the remainder gives
+ two samples per byte */
+ samples = (dec->blocksize - 7 * dec->channels) * 2 + 2 * dec->channels;
+ outsize = 2 * samples;
+ outbuf = gst_buffer_new_and_alloc (outsize);
+
+ res = adpcmdec_decode_ms_block (dec, samples, data,
+ (gint16 *) (GST_BUFFER_DATA (outbuf)));
+
+ /* Done with input data, free it */
+ gst_buffer_unref (databuf);
+
+ if (!res) {
+ gst_buffer_unref (outbuf);
+ GST_WARNING_OBJECT (dec, "Decode of block failed");
+ ret = GST_FLOW_ERROR;
+ goto done;
+ }
+
+ gst_buffer_set_caps (outbuf, dec->output_caps);
+ GST_BUFFER_TIMESTAMP (outbuf) = dec->timestamp;
+ dec->out_samples += samples / dec->channels;
+ dec->timestamp =
+ gst_util_uint64_scale_int (dec->out_samples, GST_SECOND, dec->rate);
+ GST_BUFFER_DURATION (outbuf) =
+ dec->timestamp - GST_BUFFER_TIMESTAMP (outbuf);
+
+ ret = gst_pad_push (dec->srcpad, outbuf);
+ if (ret != GST_FLOW_OK)
+ goto done;
+ }
+
+done:
+ gst_object_unref (dec);
+
+ return ret;
+}
+
+static gboolean
+adpcmdec_sink_event (GstPad * pad, GstEvent * event)
+{
+ ADPCMDec *dec = (ADPCMDec *) gst_pad_get_parent (pad);
+ gboolean res;
+ switch (GST_EVENT_TYPE (event)) {
+ case GST_EVENT_FLUSH_STOP:
+ gst_adapter_clear (dec->adapter);
+ /* Fall through */
+ default:
+ res = gst_pad_push_event (dec->srcpad, event);
+ break;
+ }
+ gst_object_unref (dec);
+ return res;
+}
+
+static GstStateChangeReturn
+adpcmdec_change_state (GstElement * element, GstStateChange transition)
+{
+ GstStateChangeReturn ret;
+ ADPCMDec *dec = (ADPCMDec *) element;
+
+ switch (transition) {
+ case GST_STATE_CHANGE_NULL_TO_READY:
+ break;
+ case GST_STATE_CHANGE_READY_TO_PAUSED:
+ break;
+ case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
+ break;
+ default:
+ break;
+ }
+
+ ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
+
+ switch (transition) {
+ case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
+ break;
+ case GST_STATE_CHANGE_PAUSED_TO_READY:
+ adpcmdec_teardown (dec);
+ break;
+ case GST_STATE_CHANGE_READY_TO_NULL:
+ break;
+ default:
+ break;
+ }
+ return ret;
+}
+
+static void
+adpcmdec_dispose (GObject * obj)
+{
+ G_OBJECT_CLASS (parent_class)->dispose (obj);
+}
+
+static void
+adpcmdec_init (ADPCMDec * dec, ADPCMDecClass * klass)
+{
+ dec->sinkpad =
+ gst_pad_new_from_static_template (&adpcmdec_sink_template, "sink");
+ gst_pad_set_setcaps_function (dec->sinkpad,
+ GST_DEBUG_FUNCPTR (adpcmdec_sink_setcaps));
+ gst_pad_set_chain_function (dec->sinkpad, GST_DEBUG_FUNCPTR (adpcmdec_chain));
+ gst_pad_set_event_function (dec->sinkpad,
+ GST_DEBUG_FUNCPTR (adpcmdec_sink_event));
+ gst_element_add_pad (GST_ELEMENT (dec), dec->sinkpad);
+ dec->srcpad =
+ gst_pad_new_from_static_template (&adpcmdec_src_template, "src");
+ gst_element_add_pad (GST_ELEMENT (dec), dec->srcpad);
+}
+
+static void
+adpcmdec_class_init (ADPCMDecClass * klass)
+{
+ GObjectClass *gobjectclass = (GObjectClass *) klass;
+ GstElementClass *gstelement_class = (GstElementClass *) klass;
+ gobjectclass->dispose = adpcmdec_dispose;
+ gstelement_class->change_state = adpcmdec_change_state;
+} static void
+
+adpcmdec_base_init (gpointer klass)
+{
+ GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
+ gst_element_class_add_pad_template (element_class,
+ gst_static_pad_template_get (&adpcmdec_sink_template));
+ gst_element_class_add_pad_template (element_class,
+ gst_static_pad_template_get (&adpcmdec_src_template));
+ gst_element_class_set_details (element_class, &adpcmdec_details);
+}
+
+static gboolean
+plugin_init (GstPlugin * plugin)
+{
+ GST_DEBUG_CATEGORY_INIT (adpcmdec_debug, "adpcmdec", 0, "ADPCM Decoders");
+ if (!gst_element_register (plugin, "msadpcmdec", GST_RANK_PRIMARY,
+ GST_TYPE_ADPCM_DEC)) {
+ return FALSE;
+ }
+ return TRUE;
+}
+
+GST_PLUGIN_DEFINE (GST_VERSION_MAJOR, GST_VERSION_MINOR, "adpcmdec",
+ "ADPCM decoder", plugin_init, VERSION, "LGPL", GST_PACKAGE_NAME,
+ GST_PACKAGE_ORIGIN);