gr::fec::async_decoder Class Reference

Creates the decoder block for use in GNU Radio flowgraphs from a given FEC API object derived from the generic_decoder class. More...

#include <gnuradio/fec/async_decoder.h>

Public Types
typedef boost::shared_ptr< async_decoder >	sptr
Public Types inherited from gr::block
enum	{ WORK_CALLED_PRODUCE = -2, WORK_DONE = -1 }
	Magic return values from general_work. More...
enum	tag_propagation_policy_t { TPP_DONT = 0, TPP_ALL_TO_ALL = 1, TPP_ONE_TO_ONE = 2, TPP_CUSTOM = 3 }
	enum to represent different tag propagation policies. More...

Public Member Functions
virtual int	general_work (int noutput_items, gr_vector_int &ninput_items, gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)=0
	compute output items from input items More...
Public Member Functions inherited from gr::block
virtual	~block ()
unsigned	history () const
void	set_history (unsigned history)
void	declare_sample_delay (int which, unsigned delay)
void	declare_sample_delay (unsigned delay)
unsigned	sample_delay (int which) const
bool	fixed_rate () const
	Return true if this block has a fixed input to output rate. More...
virtual void	forecast (int noutput_items, gr_vector_int &ninput_items_required)
	Estimate input requirements given output request. More...
virtual bool	start ()
	Called to enable drivers, etc for i/o devices. More...
virtual bool	stop ()
	Called to disable drivers, etc for i/o devices. More...
void	set_output_multiple (int multiple)
	Constrain the noutput_items argument passed to forecast and general_work. More...
int	output_multiple () const
bool	output_multiple_set () const
void	set_alignment (int multiple)
	Constrains buffers to work on a set item alignment (for SIMD) More...
int	alignment () const
void	set_unaligned (int na)
int	unaligned () const
void	set_is_unaligned (bool u)
bool	is_unaligned () const
void	consume (int which_input, int how_many_items)
	Tell the scheduler how_many_items of input stream which_input were consumed. More...
void	consume_each (int how_many_items)
	Tell the scheduler how_many_items were consumed on each input stream. More...
void	produce (int which_output, int how_many_items)
	Tell the scheduler how_many_items were produced on output stream which_output. More...
void	set_relative_rate (double relative_rate)
	Set the approximate output rate / input rate. More...
void	set_inverse_relative_rate (double inverse_relative_rate)
	Set the approximate output rate / input rate using its reciprocal. More...
void	set_relative_rate (uint64_t interpolation, uint64_t decimation)
	Set the approximate output rate / input rate as an integer ratio. More...
double	relative_rate () const
	return the approximate output rate / input rate More...
uint64_t	relative_rate_i () const
	return the numerator, or interpolation rate, of the approximate output rate / input rate More...
uint64_t	relative_rate_d () const
	return the denominator, or decimation rate, of the approximate output rate / input rate More...
mpq_class &	mp_relative_rate ()
	return a reference to the multiple precision rational represntation of the approximate output rate / input rate More...
virtual int	fixed_rate_ninput_to_noutput (int ninput)
	Given ninput samples, return number of output samples that will be produced. N.B. this is only defined if fixed_rate returns true. Generally speaking, you don't need to override this. More...
virtual int	fixed_rate_noutput_to_ninput (int noutput)
	Given noutput samples, return number of input samples required to produce noutput. N.B. this is only defined if fixed_rate returns true. Generally speaking, you don't need to override this. More...
uint64_t	nitems_read (unsigned int which_input)
	Return the number of items read on input stream which_input. More...
uint64_t	nitems_written (unsigned int which_output)
	Return the number of items written on output stream which_output. More...
tag_propagation_policy_t	tag_propagation_policy ()
	Asks for the policy used by the scheduler to moved tags downstream. More...
void	set_tag_propagation_policy (tag_propagation_policy_t p)
	Set the policy by the scheduler to determine how tags are moved downstream. More...
int	min_noutput_items () const
	Return the minimum number of output items this block can produce during a call to work. More...
void	set_min_noutput_items (int m)
	Set the minimum number of output items this block can produce during a call to work. More...
int	max_noutput_items ()
	Return the maximum number of output items this block will handle during a call to work. More...
void	set_max_noutput_items (int m)
	Set the maximum number of output items this block will handle during a call to work. More...
void	unset_max_noutput_items ()
	Clear the switch for using the max_noutput_items value of this block. More...
bool	is_set_max_noutput_items ()
	Ask the block if the flag is or is not set to use the internal value of max_noutput_items during a call to work. More...
void	expand_minmax_buffer (int port)
long	max_output_buffer (size_t i)
	Returns max buffer size on output port i. More...
void	set_max_output_buffer (long max_output_buffer)
	Request limit on max buffer size on all output ports. More...
void	set_max_output_buffer (int port, long max_output_buffer)
	Request limit on max buffer size on output port port. More...
long	min_output_buffer (size_t i)
	Returns min buffer size on output port i. More...
void	set_min_output_buffer (long min_output_buffer)
	Request limit on the minimum buffer size on all output ports. More...
void	set_min_output_buffer (int port, long min_output_buffer)
	Request limit on min buffer size on output port port. More...
float	pc_noutput_items ()
	Gets instantaneous noutput_items performance counter. More...
float	pc_noutput_items_avg ()
	Gets average noutput_items performance counter. More...
float	pc_noutput_items_var ()
	Gets variance of noutput_items performance counter. More...
float	pc_nproduced ()
	Gets instantaneous num items produced performance counter. More...
float	pc_nproduced_avg ()
	Gets average num items produced performance counter. More...
float	pc_nproduced_var ()
	Gets variance of num items produced performance counter. More...
float	pc_input_buffers_full (int which)
	Gets instantaneous fullness of which input buffer. More...
float	pc_input_buffers_full_avg (int which)
	Gets average fullness of which input buffer. More...
float	pc_input_buffers_full_var (int which)
	Gets variance of fullness of which input buffer. More...
std::vector< float >	pc_input_buffers_full ()
	Gets instantaneous fullness of all input buffers. More...
std::vector< float >	pc_input_buffers_full_avg ()
	Gets average fullness of all input buffers. More...
std::vector< float >	pc_input_buffers_full_var ()
	Gets variance of fullness of all input buffers. More...
float	pc_output_buffers_full (int which)
	Gets instantaneous fullness of which output buffer. More...
float	pc_output_buffers_full_avg (int which)
	Gets average fullness of which output buffer. More...
float	pc_output_buffers_full_var (int which)
	Gets variance of fullness of which output buffer. More...
std::vector< float >	pc_output_buffers_full ()
	Gets instantaneous fullness of all output buffers. More...
std::vector< float >	pc_output_buffers_full_avg ()
	Gets average fullness of all output buffers. More...
std::vector< float >	pc_output_buffers_full_var ()
	Gets variance of fullness of all output buffers. More...
float	pc_work_time ()
	Gets instantaneous clock cycles spent in work. More...
float	pc_work_time_avg ()
	Gets average clock cycles spent in work. More...
float	pc_work_time_var ()
	Gets average clock cycles spent in work. More...
float	pc_work_time_total ()
	Gets total clock cycles spent in work. More...
float	pc_throughput_avg ()
	Gets average throughput. More...
void	reset_perf_counters ()
	Resets the performance counters. More...
void	setup_pc_rpc ()
	Sets up export of perf. counters to ControlPort. Only called by the scheduler. More...
bool	is_pc_rpc_set ()
	Checks if this block is already exporting perf. counters to ControlPort. More...
void	no_pc_rpc ()
	If the block calls this in its constructor, it's perf. counters will not be exported. More...
void	set_processor_affinity (const std::vector< int > &mask)
	Set the thread's affinity to processor core n. More...
void	unset_processor_affinity ()
	Remove processor affinity to a specific core. More...
std::vector< int >	processor_affinity ()
	Get the current processor affinity. More...
int	active_thread_priority ()
	Get the current thread priority in use. More...
int	thread_priority ()
	Get the current thread priority stored. More...
int	set_thread_priority (int priority)
	Set the current thread priority. More...
bool	update_rate () const
void	system_handler (pmt::pmt_t msg)
	the system message handler More...
void	set_log_level (std::string level)
	Set the logger's output level. More...
std::string	log_level ()
	Get the logger's output level. More...
bool	finished ()
	returns true when execution has completed due to a message connection More...
block_detail_sptr	detail () const
void	set_detail (block_detail_sptr detail)
void	notify_msg_neighbors ()
	Tell msg neighbors we are finished. More...
void	clear_finished ()
	Make sure we don't think we are finished. More...
std::string	identifier () const
Public Member Functions inherited from gr::basic_block
pmt::pmt_t	message_subscribers (pmt::pmt_t port)
virtual	~basic_block ()
long	unique_id () const
long	symbolic_id () const
std::string	name () const
std::string	symbol_name () const
std::string	identifier () const
gr::io_signature::sptr	input_signature () const
gr::io_signature::sptr	output_signature () const
basic_block_sptr	to_basic_block ()
bool	alias_set () const
std::string	alias () const
pmt::pmt_t	alias_pmt () const
void	set_block_alias (std::string name)
void	message_port_register_in (pmt::pmt_t port_id)
void	message_port_register_out (pmt::pmt_t port_id)
void	message_port_pub (pmt::pmt_t port_id, pmt::pmt_t msg)
void	message_port_sub (pmt::pmt_t port_id, pmt::pmt_t target)
void	message_port_unsub (pmt::pmt_t port_id, pmt::pmt_t target)
virtual bool	message_port_is_hier (pmt::pmt_t port_id)
virtual bool	message_port_is_hier_in (pmt::pmt_t port_id)
virtual bool	message_port_is_hier_out (pmt::pmt_t port_id)
pmt::pmt_t	message_ports_in ()
	Get input message port names. More...
pmt::pmt_t	message_ports_out ()
	Get output message port names. More...
void	_post (pmt::pmt_t which_port, pmt::pmt_t msg)
bool	empty_p (pmt::pmt_t which_port)
	is the queue empty? More...
bool	empty_p ()
bool	empty_handled_p (pmt::pmt_t which_port)
	are all msg ports with handlers empty? More...
bool	empty_handled_p ()
size_t	nmsgs (pmt::pmt_t which_port)
	How many messages in the queue? More...
void	insert_tail (pmt::pmt_t which_port, pmt::pmt_t msg)
pmt::pmt_t	delete_head_nowait (pmt::pmt_t which_port)
msg_queue_t::iterator	get_iterator (pmt::pmt_t which_port)
void	erase_msg (pmt::pmt_t which_port, msg_queue_t::iterator it)
virtual bool	has_msg_port (pmt::pmt_t which_port)
const msg_queue_map_t &	get_msg_map (void) const
virtual void	setup_rpc ()
	Set up the RPC registered variables. More...
bool	is_rpc_set ()
	Ask if this block has been registered to the RPC. More...
void	rpc_set ()
	When the block is registered with the RPC, set this. More...
virtual bool	check_topology (int ninputs, int noutputs)
	Confirm that ninputs and noutputs is an acceptable combination. More...
template<typename T >
void	set_msg_handler (pmt::pmt_t which_port, T msg_handler)
	Set the callback that is fired when messages are available. More...
Public Member Functions inherited from gr::msg_accepter
	msg_accepter ()
	~msg_accepter ()
void	post (pmt::pmt_t which_port, pmt::pmt_t msg)
	send msg to msg_accepter on port which_port More...
Public Member Functions inherited from gr::messages::msg_accepter
	msg_accepter ()

Static Public Member Functions
static sptr	make (generic_decoder::sptr my_decoder, bool packed=false, bool rev_pack=true, int mtu=1500)

Additional Inherited Members
Protected Types inherited from gr::basic_block
enum	vcolor { WHITE, GREY, BLACK }
Protected Member Functions inherited from gr::block
	block (void)
	block (const std::string &name, gr::io_signature::sptr input_signature, gr::io_signature::sptr output_signature)
void	set_fixed_rate (bool fixed_rate)
void	add_item_tag (unsigned int which_output, uint64_t abs_offset, const pmt::pmt_t &key, const pmt::pmt_t &value, const pmt::pmt_t &srcid=pmt::PMT_F)
	Adds a new tag onto the given output buffer. More...
void	add_item_tag (unsigned int which_output, const tag_t &tag)
	Adds a new tag onto the given output buffer. More...
void	remove_item_tag (unsigned int which_input, uint64_t abs_offset, const pmt::pmt_t &key, const pmt::pmt_t &value, const pmt::pmt_t &srcid=pmt::PMT_F)
	DEPRECATED. Will be removed in 3.8. More...
void	remove_item_tag (unsigned int which_input, const tag_t &tag)
	DEPRECATED. Will be removed in 3.8. More...
void	get_tags_in_range (std::vector< tag_t > &v, unsigned int which_input, uint64_t abs_start, uint64_t abs_end)
	Given a [start,end), returns a vector of all tags in the range. More...
void	get_tags_in_range (std::vector< tag_t > &v, unsigned int which_input, uint64_t abs_start, uint64_t abs_end, const pmt::pmt_t &key)
	Given a [start,end), returns a vector of all tags in the range with a given key. More...
void	get_tags_in_window (std::vector< tag_t > &v, unsigned int which_input, uint64_t rel_start, uint64_t rel_end)
	Gets all tags within the relative window of the current call to work. More...
void	get_tags_in_window (std::vector< tag_t > &v, unsigned int which_input, uint64_t rel_start, uint64_t rel_end, const pmt::pmt_t &key)
	Operates like gr::block::get_tags_in_window with the ability to only return tags with the specified key. More...
void	enable_update_rate (bool en)
Protected Member Functions inherited from gr::basic_block
	basic_block (void)
	basic_block (const std::string &name, gr::io_signature::sptr input_signature, gr::io_signature::sptr output_signature)
	Protected constructor prevents instantiation by non-derived classes. More...
void	set_input_signature (gr::io_signature::sptr iosig)
	may only be called during constructor More...
void	set_output_signature (gr::io_signature::sptr iosig)
	may only be called during constructor More...
void	set_color (vcolor color)
	Allow the flowgraph to set for sorting and partitioning. More...
vcolor	color () const
virtual bool	has_msg_handler (pmt::pmt_t which_port)
	Tests if there is a handler attached to port which_port. More...
virtual void	dispatch_msg (pmt::pmt_t which_port, pmt::pmt_t msg)
Protected Attributes inherited from gr::block
std::vector< long >	d_max_output_buffer
std::vector< long >	d_min_output_buffer
gr::thread::mutex	d_setlock
gr::logger_ptr	d_logger
gr::logger_ptr	d_debug_logger
const pmt::pmt_t	d_pmt_done
const pmt::pmt_t	d_system_port
Protected Attributes inherited from gr::basic_block
std::string	d_name
gr::io_signature::sptr	d_input_signature
gr::io_signature::sptr	d_output_signature
long	d_unique_id
long	d_symbolic_id
std::string	d_symbol_name
std::string	d_symbol_alias
vcolor	d_color
bool	d_rpc_set
msg_queue_map_t	msg_queue
std::vector< rpcbasic_sptr >	d_rpc_vars
pmt::pmt_t	d_message_subscribers

Detailed Description

Creates the decoder block for use in GNU Radio flowgraphs from a given FEC API object derived from the generic_decoder class.

Decodes frames received as async messages over a message port. This decoder deployment expects messages of soft decision symbols in and can produce either packed, PDU messages (packed = True) or messages full of unpacked bits (packed = False).

This decoder works off a full message as one frame or block to decode. The message length is used to calculate the frame length. To support this, the decoder variable used will have had its frame_size set. This block treats that initial frame_size value as the maximum transmission unit (MTU) and will not process frames larger than that after being decoded.

The packed PDU form of this deployment is designed to work well with other PDU-based blocks to operate within the processing flow of data packets or frames.

Due to differences in how data is packed and processed, this block also offers the ability to change the direction of how bits are packed. All inputs messages are one soft decision per item. By default, the rev_pack mode is set to True. Using this setup allows the async block to behave with PDUs in the same operation and format as the tagged stream decoders. That is, putting the same data into both the tagged stream decoder deployment and this with the default setting should produce the same data.

Because the block handles data as a full frame per message, this decoder deployment cannot work with any decoders that require history. For example, the gr::fec::code::cc_decoder decoder in streaming mode requires an extra rate*(K-1) bits to complete the decoding, so it would have to wait for the next message to come in and finish processing. Therefore, the streaming mode of the CC decoder is not allowed. The other three modes will work with this deployment since the frame is self-contained for decoding.

Member Typedef Documentation

sptr

typedef boost::shared_ptr<async_decoder> gr::fec::async_decoder::sptr

Member Function Documentation

general_work()

virtual int gr::fec::async_decoder::general_work ( int  noutput_items, gr_vector_int &  ninput_items, gr_vector_const_void_star &  input_items, gr_vector_void_star &  output_items  )

pure virtual

compute output items from input items

Parameters

noutput_items	number of output items to write on each output stream
ninput_items	number of input items available on each input stream
input_items	vector of pointers to the input items, one entry per input stream
output_items	vector of pointers to the output items, one entry per output stream

Returns

number of items actually written to each output stream or WORK_CALLED_PRODUCE or WORK_DONE. It is OK to return a value less than noutput_items.

WORK_CALLED_PRODUCE is used where not all outputs produce the same number of items. general_work must call produce() for each output to indicate the number of items actually produced.

WORK_DONE indicates that no more data will be produced by this block.

general_work must call consume or consume_each to indicate how many items were consumed on each input stream.

Reimplemented from gr::block.

make()

static sptr gr::fec::async_decoder::make ( generic_decoder::sptr  my_decoder, bool  packed = false, bool  rev_pack = true, int  mtu = 1500  )

static

Build the PDU-based FEC decoder block from an FECAPI decoder object.

Parameters

my_decoder	An FECAPI decoder object child of the generic_decoder class.
packed	Sets output to packed bytes if true; otherwise, 1 bit per byte.
rev_pack	If packing bits, should they be reversed?
mtu	The Maximum Transmission Unit (MTU) of the output frame that the block will be able to process. Specified in bytes and defaults to 1500.

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The documentation for this class was generated from the following file:

• async_decoder.h