gstsbcparse.c

Linux的蓝牙操作工具。配合bluez-lib使用

/*
 *
 *  BlueZ - Bluetooth protocol stack for Linux
 *
 *  Copyright (C) 2004-2007  Marcel Holtmann <[e-mail]>
 *
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser 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
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser 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
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <string.h>

#include "gstsbcparse.h"
#include "gstsbcutil.h"

GST_DEBUG_CATEGORY_STATIC(sbc_parse_debug);
#define GST_CAT_DEFAULT sbc_parse_debug

GST_BOILERPLATE(GstSbcParse, gst_sbc_parse, GstElement, GST_TYPE_ELEMENT);

static const GstElementDetails sbc_parse_details =
	GST_ELEMENT_DETAILS("Bluetooth SBC parser",
				"Codec/Parser/Audio",
				"Parse a SBC audio stream",
				"Marcel Holtmann <[e-mail]>");

static GstStaticPadTemplate sbc_parse_sink_factory =
	GST_STATIC_PAD_TEMPLATE("sink", GST_PAD_SINK, GST_PAD_ALWAYS,
		GST_STATIC_CAPS("audio/x-sbc"));

static GstStaticPadTemplate sbc_parse_src_factory =
	GST_STATIC_PAD_TEMPLATE("src", GST_PAD_SRC, GST_PAD_ALWAYS,
		GST_STATIC_CAPS("audio/x-sbc, "
				"rate = (int) { 16000, 32000, 44100, 48000 }, "
				"channels = (int) [ 1, 2 ], "
				"mode = (string) { mono, dual, stereo, joint }, "
				"blocks = (int) { 4, 8, 12, 16 }, "
				"subbands = (int) { 4, 8 }, "
				"allocation = (string) { snr, loudness },"
				"bitpool = (int) [ 2, 64 ]"));

/* Creates a fixed caps from the caps given. */
/* FIXME use gstsbcutil caps fixating function */
static GstCaps* sbc_parse_select_caps(GstSbcParse *parse, GstCaps *caps)
{
	GstCaps *result;
	GstStructure *structure;
	const GValue *value;
	gboolean error = FALSE;
	gint temp, rate, channels, blocks, subbands, bitpool;
	const gchar* allocation = NULL;
	const gchar* mode = NULL;
	const gchar* error_message = NULL;
	gchar* str;

	str = gst_caps_to_string(caps);
	GST_DEBUG_OBJECT(parse, "Parsing caps: %s", str);
	g_free(str);

	structure = gst_caps_get_structure(caps, 0);

	if (!gst_structure_has_field(structure, "rate")) {
		error = TRUE;
		error_message = "no rate.";
		goto error;
	} else {
		value = gst_structure_get_value(structure, "rate");
		if (GST_VALUE_HOLDS_LIST(value))
			temp = gst_sbc_select_rate_from_list(value);
		else
			temp = g_value_get_int(value);
		rate = temp;
	}

	if (!gst_structure_has_field(structure, "channels")) {
		error = TRUE;
		error_message = "no channels.";
		goto error;
	} else {
		value = gst_structure_get_value(structure, "channels");
		if (GST_VALUE_HOLDS_INT_RANGE(value))
			temp = gst_sbc_select_channels_from_range(value);
		else
			temp = g_value_get_int(value);
		channels = temp;
	}

	if (!gst_structure_has_field(structure, "blocks")) {
		error = TRUE;
		error_message = "no blocks.";
		goto error;
	} else {
		value = gst_structure_get_value(structure, "blocks");
		if (GST_VALUE_HOLDS_LIST(value))
			temp = gst_sbc_select_blocks_from_list(value);
		else
			temp = g_value_get_int(value);
		blocks = temp;
	}

	if (!gst_structure_has_field(structure, "subbands")) {
		error = TRUE;
		error_message = "no subbands.";
		goto error;
	} else {
		value = gst_structure_get_value(structure, "subbands");
		if (GST_VALUE_HOLDS_LIST(value))
			temp = gst_sbc_select_subbands_from_list(value);
		else
			temp = g_value_get_int(value);
		subbands = temp;
	}

	if (!gst_structure_has_field(structure, "bitpool")) {
		error = TRUE;
		error_message = "no bitpool";
		goto error;
	} else {
		value = gst_structure_get_value(structure, "bitpool");
		if (GST_VALUE_HOLDS_INT_RANGE(value))
			temp = gst_sbc_select_bitpool_from_range(value);
		else
			temp = g_value_get_int(value);
		bitpool = temp;
	}

	if (!gst_structure_has_field(structure, "allocation")) {
		error = TRUE;
		error_message = "no allocation.";
		goto error;
	} else {
		value = gst_structure_get_value(structure, "allocation");
		if (GST_VALUE_HOLDS_LIST(value))
			allocation = gst_sbc_get_allocation_from_list(value);
		else
			allocation = g_value_get_string(value);
	}

	if (!gst_structure_has_field(structure, "mode")) {
		error = TRUE;
		error_message = "no mode.";
		goto error;
	} else {
		value = gst_structure_get_value(structure, "mode");
		if (GST_VALUE_HOLDS_LIST(value))
			mode = gst_sbc_get_mode_from_list(value);
		else
			mode = g_value_get_string(value);
	}

error:
	if (error) {
		GST_ERROR_OBJECT (parse, "Invalid input caps: %s",
				error_message);
		return NULL;
	}

	result = gst_caps_new_simple("audio/x-sbc",
					"rate", G_TYPE_INT, rate,
					"channels", G_TYPE_INT, channels,
					"mode", G_TYPE_STRING, mode,
					"blocks", G_TYPE_INT, blocks,
					"subbands", G_TYPE_INT, subbands,
					"allocation", G_TYPE_STRING, allocation,
					"bitpool", G_TYPE_INT, bitpool,
					NULL);
	parse->sbc.rate = rate;
	parse->sbc.channels = channels;
	parse->sbc.blocks = blocks;
	parse->sbc.subbands = subbands;
	parse->sbc.bitpool = bitpool;
	parse->sbc.joint = gst_sbc_get_mode_int(mode);
	parse->sbc.allocation = gst_sbc_get_allocation_mode_int(allocation);

	return result;
}

static gboolean sbc_parse_sink_setcaps(GstPad * pad, GstCaps * caps)
{
	GstSbcParse *parse;
	GstCaps *inter, *other, *srccaps;

	parse = GST_SBC_PARSE(GST_PAD_PARENT(pad));

	other = gst_pad_peer_get_caps(parse->srcpad);
	if (other == NULL)
		other = gst_caps_new_any();

	inter = gst_caps_intersect(caps, other);
	if (gst_caps_is_empty(inter)) {
		gst_caps_unref(inter);
		return FALSE;
	}
	srccaps = sbc_parse_select_caps(parse, inter);
	if (srccaps == NULL) {
		gst_caps_unref(inter);
		return FALSE;
	}

	gst_pad_set_caps(parse->srcpad, srccaps);

	gst_caps_unref(inter);
	gst_caps_unref(other);
	gst_caps_unref(srccaps);

	return TRUE;
}

static GstFlowReturn sbc_parse_chain(GstPad *pad, GstBuffer *buffer)
{
	GstSbcParse *parse = GST_SBC_PARSE(gst_pad_get_parent(pad));
	GstFlowReturn res = GST_FLOW_OK;
	guint size, offset = 0;
	guint8 *data;
	GstClockTime timestamp;

	timestamp = GST_BUFFER_TIMESTAMP(buffer);

	if (parse->buffer) {
		GstBuffer *temp = buffer;
		buffer = gst_buffer_span(parse->buffer, 0, buffer,
			GST_BUFFER_SIZE(parse->buffer) + GST_BUFFER_SIZE(buffer));
		gst_buffer_unref(temp);
		gst_buffer_unref(parse->buffer);
		parse->buffer = NULL;
	}

	data = GST_BUFFER_DATA(buffer);
	size = GST_BUFFER_SIZE(buffer);

	while (offset < size) {
		GstBuffer *output;
		GstCaps *temp;
		int consumed;

		consumed = sbc_parse(&parse->sbc, data + offset, size - offset);
		if (consumed <= 0)
			break;

		temp = GST_PAD_CAPS(parse->srcpad);

		res = gst_pad_alloc_buffer_and_set_caps(parse->srcpad,
						GST_BUFFER_OFFSET_NONE,
						consumed, temp, &output);

		if (res != GST_FLOW_OK)
			goto done;

		memcpy(GST_BUFFER_DATA(output), data + offset, consumed);

		res = gst_pad_push(parse->srcpad, output);
		if (res != GST_FLOW_OK)
			goto done;

		offset += consumed;
	}

	if (offset < size)
		parse->buffer = gst_buffer_create_sub(buffer,
							offset, size - offset);

done:
	gst_buffer_unref(buffer);
	gst_object_unref(parse);

	return res;
}

static GstStateChangeReturn sbc_parse_change_state(GstElement *element,
						GstStateChange transition)
{
	GstSbcParse *parse = GST_SBC_PARSE(element);

	switch (transition) {
	case GST_STATE_CHANGE_READY_TO_PAUSED:
		GST_DEBUG("Setup subband codec");
		if (parse->buffer) {
			gst_buffer_unref(parse->buffer);
			parse->buffer = NULL;
		}
		sbc_init(&parse->sbc, 0);
		break;

	case GST_STATE_CHANGE_PAUSED_TO_READY:
		GST_DEBUG("Finish subband codec");
		if (parse->buffer) {
			gst_buffer_unref(parse->buffer);
			parse->buffer = NULL;
		}
		sbc_finish(&parse->sbc);
		break;

	default:
		break;
	}

	return parent_class->change_state(element, transition);
}

static void gst_sbc_parse_base_init(gpointer g_class)
{
	GstElementClass *element_class = GST_ELEMENT_CLASS(g_class);

	gst_element_class_add_pad_template(element_class,
		gst_static_pad_template_get(&sbc_parse_sink_factory));

	gst_element_class_add_pad_template(element_class,
		gst_static_pad_template_get(&sbc_parse_src_factory));

	gst_element_class_set_details(element_class, &sbc_parse_details);
}

static void gst_sbc_parse_class_init(GstSbcParseClass *klass)
{
	GstElementClass *element_class = GST_ELEMENT_CLASS(klass);

	parent_class = g_type_class_peek_parent(klass);

	element_class->change_state = GST_DEBUG_FUNCPTR(sbc_parse_change_state);

	GST_DEBUG_CATEGORY_INIT(sbc_parse_debug, "sbcparse", 0,
				"SBC parsing element");
}

static void gst_sbc_parse_init(GstSbcParse *self, GstSbcParseClass *klass)
{
	self->sinkpad = gst_pad_new_from_static_template(&sbc_parse_sink_factory, "sink");
	gst_pad_set_chain_function(self->sinkpad, GST_DEBUG_FUNCPTR(sbc_parse_chain));
	gst_pad_set_setcaps_function (self->sinkpad,
		GST_DEBUG_FUNCPTR (sbc_parse_sink_setcaps));
	gst_element_add_pad(GST_ELEMENT(self), self->sinkpad);

	self->srcpad = gst_pad_new_from_static_template(&sbc_parse_src_factory, "src");
	gst_element_add_pad(GST_ELEMENT(self), self->srcpad);
}