diff options
Diffstat (limited to 'gst/adpcmdec')
-rw-r--r-- | gst/adpcmdec/Makefile.am | 12 | ||||
-rw-r--r-- | gst/adpcmdec/adpcmdec.c | 452 |
2 files changed, 464 insertions, 0 deletions
diff --git a/gst/adpcmdec/Makefile.am b/gst/adpcmdec/Makefile.am new file mode 100644 index 00000000..5c60ad4f --- /dev/null +++ b/gst/adpcmdec/Makefile.am @@ -0,0 +1,12 @@ +plugin_LTLIBRARIES = libgstadpcmdec.la + +# sources used to compile this plug-in +libgstadpcmdec_la_SOURCES = adpcmdec.c + +# flags used to compile this plugin +# add other _CFLAGS and _LIBS as needed +libgstadpcmdec_la_CFLAGS = $(GST_CFLAGS) $(GST_BASE_CFLAGS) +libgstadpcmdec_la_LIBADD = $(GST_LIBS) $(GST_BASE_LIBS) +libgstadpcmdec_la_LDFLAGS = $(GST_PLUGIN_LDFLAGS) +libgstadpcmdec_la_LIBTOOLFLAGS = --tag=disable-static + diff --git a/gst/adpcmdec/adpcmdec.c b/gst/adpcmdec/adpcmdec.c new file mode 100644 index 00000000..c58dc5d8 --- /dev/null +++ b/gst/adpcmdec/adpcmdec.c @@ -0,0 +1,452 @@ +/* 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); |