/* GStreamer * Copyright (C) 2009 Pioneers of the Inevitable * * Authors: Michael Smith * * 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 ADPCM decoders in libsndfile, Copyright (C) 1999-2002 Erik de Castro Lopo #include #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 GstStaticPadTemplate adpcmdec_sink_template = GST_STATIC_PAD_TEMPLATE ("sink", GST_PAD_SINK, GST_PAD_ALWAYS, GST_STATIC_CAPS ("audio/x-adpcm, " " layout=(string){microsoft, dvi}, " " block_align = (int) [64, 8192], " " 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]") ); enum adpcm_layout { LAYOUT_ADPCM_MICROSOFT, LAYOUT_ADPCM_DVI }; typedef struct _ADPCMDecClass { GstElementClass parent_class; } ADPCMDecClass; typedef struct _ADPCMDec { GstElement parent; GstPad *sinkpad; GstPad *srcpad; GstCaps *output_caps; enum adpcm_layout layout; int rate; int channels; int blocksize; gboolean is_setup; GstClockTime timestamp; GstClockTime base_timestamp; guint64 out_samples; GstAdapter *adapter; } ADPCMDec; GType adpcmdec_get_type (void); 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->base_timestamp = GST_CLOCK_TIME_NONE; dec->adapter = gst_adapter_new (); dec->out_samples = 0; return TRUE; } 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); const gchar *layout; layout = gst_structure_get_string (structure, "layout"); if (!layout) return FALSE; if (g_str_equal (layout, "microsoft")) dec->layout = LAYOUT_ADPCM_MICROSOFT; else if (g_str_equal (layout, "dvi")) dec->layout = LAYOUT_ADPCM_DVI; else return FALSE; if (!gst_structure_get_int (structure, "block_align", &dec->blocksize)) dec->blocksize = -1; /* Not provided */ 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 const int AdaptationTable[] = { 230, 230, 230, 230, 307, 409, 512, 614, 768, 614, 512, 409, 307, 230, 230, 230 }; static const int AdaptCoeff1[] = { 256, 512, 0, 192, 240, 460, 392 }; static const int AdaptCoeff2[] = { 0, -256, 0, 64, 0, -208, -232 }; static gint16 read_sample (const 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, const 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 const int ima_indx_adjust[16] = { -1, -1, -1, -1, 2, 4, 6, 8, -1, -1, -1, -1, 2, 4, 6, 8, }; static const int ima_step_size[89] = { 7, 8, 9, 10, 11, 12, 13, 14, 16, 17, 19, 21, 23, 25, 28, 31, 34, 37, 41, 45, 50, 55, 60, 66, 73, 80, 88, 97, 107, 118, 130, 143, 157, 173, 190, 209, 230, 253, 279, 307, 337, 371, 408, 449, 494, 544, 598, 658, 724, 796, 876, 963, 1060, 1166, 1282, 1411, 1552, 1707, 1878, 2066, 2272, 2499, 2749, 3024, 3327, 3660, 4026, 4428, 4871, 5358, 5894, 6484, 7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899, 15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794, 32767 }; /* 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_ima_block (ADPCMDec * dec, int n_samples, const guint8 * data, gint16 * samples) { gint16 stepindex[2]; int channel; int idx; int i, j; int sample; if ((n_samples - dec->channels) % 8 != 0) { GST_WARNING_OBJECT (dec, "Input not correct size"); return FALSE; } for (channel = 0; channel < dec->channels; channel++) { samples[channel] = read_sample (data + channel * 4); stepindex[channel] = MIN (data[channel * 4 + 2], 88); if (data[channel * 4 + 3] != 0) { GST_WARNING_OBJECT (dec, "Synchronisation error"); return FALSE; } } i = dec->channels; idx = 4 * dec->channels; while (i < n_samples) { for (channel = 0; channel < dec->channels; channel++) { sample = i + channel; for (j = 0; j < 8; j++) { int bytecode; int step; int diff; if (j % 2 == 0) { bytecode = data[idx] & 0x0F; } else { bytecode = (data[idx] >> 4) & 0x0F; idx++; } step = ima_step_size[stepindex[channel]]; diff = (2 * (bytecode & 0x7) * step + step) / 8; if (bytecode & 8) diff = -diff; samples[sample] = CLAMP (samples[sample - dec->channels] + diff, G_MININT16, G_MAXINT16); stepindex[channel] = CLAMP (stepindex[channel] + ima_indx_adjust[bytecode], 0, 88); sample += dec->channels; } } i += 8 * dec->channels; } return TRUE; } static GstFlowReturn adpcmdec_decode_block (ADPCMDec * dec, const guint8 * data, int blocksize) { gboolean res; GstBuffer *outbuf = NULL; int outsize; int samples; if (dec->layout == LAYOUT_ADPCM_MICROSOFT) { /* 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 */ if (blocksize < 7 * dec->channels) return GST_FLOW_ERROR; samples = (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))); } else if (dec->layout == LAYOUT_ADPCM_DVI) { /* Each block has a 4 byte header per channel, include an initial sample. Then the remainder gives two samples per byte */ if (blocksize < 4 * dec->channels) return GST_FLOW_ERROR; samples = (blocksize - 4 * dec->channels) * 2 + dec->channels; outsize = 2 * samples; outbuf = gst_buffer_new_and_alloc (outsize); res = adpcmdec_decode_ima_block (dec, samples, data, (gint16 *) (GST_BUFFER_DATA (outbuf))); } else { GST_WARNING_OBJECT (dec, "Unknown layout"); return GST_FLOW_ERROR; } if (!res) { gst_buffer_unref (outbuf); GST_WARNING_OBJECT (dec, "Decode of block failed"); return GST_FLOW_ERROR; } gst_buffer_set_caps (outbuf, dec->output_caps); GST_BUFFER_TIMESTAMP (outbuf) = dec->timestamp; dec->out_samples += samples / dec->channels; dec->timestamp = dec->base_timestamp + gst_util_uint64_scale_int (dec->out_samples, GST_SECOND, dec->rate); GST_BUFFER_DURATION (outbuf) = dec->timestamp - GST_BUFFER_TIMESTAMP (outbuf); return gst_pad_push (dec->srcpad, outbuf); } static GstFlowReturn adpcmdec_chain (GstPad * pad, GstBuffer * buf) { ADPCMDec *dec = (ADPCMDec *) gst_pad_get_parent (pad); GstFlowReturn ret = GST_FLOW_OK; guint8 *data; GstBuffer *databuf = NULL; if (!dec->is_setup) adpcmdec_setup (dec); if (dec->base_timestamp == GST_CLOCK_TIME_NONE) { dec->base_timestamp = GST_BUFFER_TIMESTAMP (buf); if (dec->base_timestamp == GST_CLOCK_TIME_NONE) dec->base_timestamp = 0; dec->timestamp = dec->base_timestamp; } if (dec->blocksize > 0) { 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); ret = adpcmdec_decode_block (dec, data, dec->blocksize); /* Done with input data, free it */ gst_buffer_unref (databuf); if (ret != GST_FLOW_OK) goto done; } } else { /* No explicit blocksize; we just process one input buffer at a time */ ret = adpcmdec_decode_block (dec, GST_BUFFER_DATA (buf), GST_BUFFER_SIZE (buf)); gst_buffer_unref (buf); } 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: dec->out_samples = 0; dec->timestamp = GST_CLOCK_TIME_NONE; dec->base_timestamp = GST_CLOCK_TIME_NONE; 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_simple (element_class, "ADPCM decoder", "Codec/Decoder/Audio", "Decode MS and IMA ADPCM audio", "Pioneers of the Inevitable "); } static gboolean plugin_init (GstPlugin * plugin) { GST_DEBUG_CATEGORY_INIT (adpcmdec_debug, "adpcmdec", 0, "ADPCM Decoders"); if (!gst_element_register (plugin, "adpcmdec", 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);