gstsbcutil.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 "ipc.h"
#include "gstsbcutil.h"

/*
 * Selects one rate from a list of possible rates
 * TODO - use a better approach to this (it is selecting the last element)
 */
gint gst_sbc_select_rate_from_list(const GValue *value)
{
	guint size = gst_value_list_get_size(value);
	return g_value_get_int(gst_value_list_get_value(value, size-1));
}

/*
 * Selects one number of channels option from a range of possible numbers
 * TODO - use a better approach to this (it is selecting the maximum value)
 */
gint gst_sbc_select_channels_from_range(const GValue *value)
{
	return gst_value_get_int_range_max(value);
}

/*
 * Selects one number of blocks from a list of possible blocks
 * TODO - use a better approach to this (it is selecting the last element)
 */
gint gst_sbc_select_blocks_from_list(const GValue *value)
{
	guint size = gst_value_list_get_size(value);
	return g_value_get_int(gst_value_list_get_value(value, size-1));
}

/*
 * Selects one number of subbands from a list
 * TODO - use a better approach to this (it is selecting the last element)
 */
gint gst_sbc_select_subbands_from_list(const GValue *value)
{
	guint size = gst_value_list_get_size(value);
	return g_value_get_int(gst_value_list_get_value(value, size-1));
}

/*
 * Selects one bitpool option from a range
 * TODO - use a better approach to this (it is selecting the maximum value)
 */
gint gst_sbc_select_bitpool_from_range(const GValue *value)
{
	return gst_value_get_int_range_max(value);
}

/*
 * Selects one allocation mode from the ones on the list
 * TODO - use a better approach
 */
const gchar *gst_sbc_get_allocation_from_list(const GValue *value)
{
	guint size = gst_value_list_get_size(value);
	return g_value_get_string(gst_value_list_get_value(value, size-1));
}

/*
 * Selects one mode from the ones on the list
 * TODO - use a better aproach
 */
const gchar *gst_sbc_get_mode_from_list(const GValue *value)
{
	guint size = gst_value_list_get_size(value);
	return g_value_get_string(gst_value_list_get_value(value, size-1));
}

gint gst_sbc_get_allocation_mode_int(const gchar *allocation)
{
	if (g_ascii_strcasecmp(allocation, "loudness") == 0)
		return BT_A2DP_ALLOCATION_LOUDNESS;
	else if (g_ascii_strcasecmp(allocation, "snr") == 0)
		return BT_A2DP_ALLOCATION_SNR;
	else if (g_ascii_strcasecmp(allocation, "auto") == 0)
		return BT_A2DP_ALLOCATION_AUTO;
	else
		return -1;
}

gint gst_sbc_get_mode_int(const gchar *mode)
{
	if (g_ascii_strcasecmp(mode, "joint") == 0)
		return BT_A2DP_CHANNEL_MODE_JOINT_STEREO;
	else if (g_ascii_strcasecmp(mode, "stereo") == 0)
		return BT_A2DP_CHANNEL_MODE_STEREO;
	else if (g_ascii_strcasecmp(mode, "dual") == 0)
		return BT_A2DP_CHANNEL_MODE_DUAL_CHANNEL;
	else if (g_ascii_strcasecmp(mode, "mono") == 0)
		return BT_A2DP_CHANNEL_MODE_MONO;
	else if (g_ascii_strcasecmp(mode, "auto") == 0)
		return BT_A2DP_CHANNEL_MODE_AUTO;
	else
		return -1;
}

const gchar *gst_sbc_get_mode_string(int joint)
{
	switch (joint) {
	case BT_A2DP_CHANNEL_MODE_MONO:
		return "mono";
	case BT_A2DP_CHANNEL_MODE_DUAL_CHANNEL:
		return "dual";
	case BT_A2DP_CHANNEL_MODE_STEREO:
		return "stereo";
	case BT_A2DP_CHANNEL_MODE_JOINT_STEREO:
		return "joint";
	case BT_A2DP_CHANNEL_MODE_AUTO:
		return NULL; /* TODO what should be selected here? */
	default:
		return NULL;
	}
}

const gchar *gst_sbc_get_allocation_string(int alloc)
{
	switch (alloc) {
	case BT_A2DP_ALLOCATION_LOUDNESS:
		return "loudness";
	case BT_A2DP_ALLOCATION_SNR:
		return "snr";
	case BT_A2DP_ALLOCATION_AUTO:
		return "loudness"; /* TODO what should be selected here? */
	default:
		return NULL;
	}
}

GstCaps* gst_sbc_caps_from_sbc(sbc_capabilities_t *sbc, gint channels)
{
	GstCaps *caps;
	const gchar *mode_str;
	const gchar *allocation_str;

	mode_str = gst_sbc_get_mode_string(sbc->channel_mode);
	allocation_str = gst_sbc_get_allocation_string(sbc->allocation_method);

	caps = gst_caps_new_simple("audio/x-sbc",
				"rate", G_TYPE_INT, sbc->frequency,
				"channels", G_TYPE_INT, channels,
				"mode", G_TYPE_STRING, mode_str,
				"subbands", G_TYPE_INT, sbc->subbands,
				"blocks", G_TYPE_INT, sbc->block_length,
				"allocation", G_TYPE_STRING, allocation_str,
				"bitpool", G_TYPE_INT, sbc->max_bitpool,
				NULL);

	return caps;
}

/*
 * Given a GstCaps, this will return a fixed GstCaps on sucessfull conversion.
 * If an error occurs, it will return NULL and error_message will contain the
 * error message.
 *
 * error_message must be passed NULL, if an error occurs, the caller has the
 * ownership of the error_message, it must be freed after use.
 */
GstCaps* gst_sbc_util_caps_fixate(GstCaps *caps, gchar** error_message)
{
	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;

	g_assert(*error_message == NULL);

	structure = gst_caps_get_structure(caps, 0);

	if (!gst_structure_has_field(structure, "rate")) {
		error = TRUE;
		*error_message = g_strdup("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 = g_strdup("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 = g_strdup("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 = g_strdup("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 = g_strdup("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 = g_strdup("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 = g_strdup("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)
		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);

	return result;
}