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/*****************************************************************************
* input.h: input thread interface
* (c)1999 VideoLAN
*****************************************************************************/
/*****************************************************************************
* Constants related to input
*****************************************************************************/
#define TS_PACKET_SIZE 188 /* size of a TS packet */
#define PES_HEADER_SIZE 14 /* size of the first part of a PES header */
#define PSI_SECTION_SIZE 4096 /* Maximum size of a PSI section */
/*****************************************************************************
* ts_packet_t
*****************************************************************************
* Describe a TS packet.
*****************************************************************************/
typedef struct ts_packet_s
{
/* Nothing before this line, the code relies on that */
byte_t buffer[TS_PACKET_SIZE]; /* raw TS data packet */
/* Decoders information */
unsigned int i_payload_start;
/* start of the PES payload in this packet */
unsigned int i_payload_end; /* guess ? :-) */
/* Used to chain the TS packets that carry data for a same PES or PSI */
struct ts_packet_s * p_prev_ts;
struct ts_packet_s * p_next_ts;
} ts_packet_t;
/*****************************************************************************
* pes_packet_t
*****************************************************************************
* Describes an PES packet, with its properties, and pointers to the TS packets
* containing it.
*****************************************************************************/
typedef struct pes_packet_s
{
/* PES properties */
boolean_t b_data_loss; /* The previous (at least) PES packet
* has been lost. The decoders will have to find a way to recover. */
boolean_t b_data_alignment; /* used to find the beginning of a
* video or audio unit */
boolean_t b_has_pts; /* is the following field set ? */
mtime_t i_pts; /* the PTS for this packet (if set above) */
boolean_t b_random_access;
/* if TRUE, in the payload of this packet, there is the first byte
* of a video sequence header, or the first byte of an audio frame.
*/
u8 i_stream_id; /* payload type and id */
int i_pes_size; /* size of the current PES packet */
int i_ts_packets;/* number of TS packets in this PES */
/* Demultiplexer environment */
boolean_t b_discard_payload; /* is the packet messed up ? */
byte_t * p_pes_header; /* pointer to the PES header */
byte_t * p_pes_header_save; /* temporary buffer */
/* Pointers to TS packets (TS packets are then linked by the p_prev_ts and
p_next_ts fields of the ts_packet_t struct) */
ts_packet_t * p_first_ts; /* The first TS packet containing this
* PES (used by decoders). */
ts_packet_t * p_last_ts; /* The last TS packet gathered at present
* (used by the demultiplexer). */
} pes_packet_t;
/*****************************************************************************
* psi_section_t
*****************************************************************************
* Describes a PSI section. Beware, it doesn't contain pointers to the TS
* packets that contain it as for a PES, but the data themselves
*****************************************************************************/
typedef struct psi_section_s
{
byte_t buffer[PSI_SECTION_SIZE];
boolean_t b_running_section; /* Is there a section being decoded ? */
u16 i_length;
u16 i_current_position;
} psi_section_t;
/*****************************************************************************
* es_descriptor_t: elementary stream descriptor
*****************************************************************************
* Describes an elementary stream, and includes fields required to handle and
* demultiplex this elementary stream.
*****************************************************************************/
typedef struct es_descriptor_t
{
u16 i_id; /* stream ID, PID for TS streams */
u8 i_type; /* stream type */
boolean_t b_pcr; /* does the stream include a PCR ? */
/* XXX?? b_pcr will be replaced by something else: since a PCR can't be shared
* between several ES, we will probably store the PCR fields directly here,
* and one of those fields will probably (again) be used as a test of the
* PCR presence */
boolean_t b_psi; /* does the stream have to be handled by the
PSI decoder ? */
/* Markers */
int i_continuity_counter;
boolean_t b_discontinuity;
boolean_t b_random;
/* PES packets */
pes_packet_t * p_pes_packet;
/* current PES packet we are gathering */
/* PSI packets */
psi_section_t * p_psi_section; /* idem for a PSI stream */
/* Decoder informations */
void * p_dec; /* p_dec is void *, since we don't know a
* priori whether it is adec_thread_t or
* vdec_thread_t. We will use explicit
* casts. */
/* XXX?? video stream descriptor ? */
/* XXX?? audio stream descriptor ? */
/* XXX?? hierarchy descriptor ? */
/* XXX?? target background grid descriptor ? */
/* XXX?? video window descriptor ? */
/* XXX?? ISO 639 language descriptor ? */
#ifdef STATS
/* Stats */
count_t c_bytes; /* total bytes read */
count_t c_payload_bytes;/* total of payload usefull bytes */
count_t c_packets; /* total packets read */
count_t c_invalid_packets; /* invalid packets read */
/* XXX?? ... other stats */
#endif
} es_descriptor_t;
/* Special PID values - note that the PID is only on 13 bits, and that values
* greater than 0x1fff have no meaning in a stream */
#define PROGRAM_ASSOCIATION_TABLE_PID 0x0000
#define CONDITIONNAL_ACCESS_TABLE_PID 0x0001 /* not used */
#define EMPTY_PID 0xffff /* empty record in a table */
/* ES streams types - see ISO/IEC 13818-1 table 2-29 numbers */
#define MPEG1_VIDEO_ES 0x01
#define MPEG2_VIDEO_ES 0x02
#define MPEG1_AUDIO_ES 0x03
#define MPEG2_AUDIO_ES 0x04
#define AC3_AUDIO_ES 0x81
#define DVD_SPU_ES 0x82 /* 0x82 might violate the norm */
/*****************************************************************************
* program_descriptor_t
*****************************************************************************
* Describes a program and list associated elementary streams. It is build by
* the PSI decoder upon the informations carried in program map sections
*****************************************************************************/
typedef struct
{
/* Program characteristics */
u16 i_number; /* program number */
u8 i_version; /* version number */
boolean_t b_is_ok; /* Is the description up to date ?*/
u16 i_pcr_pid; /* PCR ES */
int i_es_number;
es_descriptor_t ** ap_es; /* array of pointers to ES */
#ifdef DVB_EXTENSIONS
/* Service Descriptor (program name) */
u8 i_srv_type;
char* psz_srv_name;
#endif
/* XXX?? target background grid descriptor ? */
/* XXX?? video window descriptor ? */
/* XXX?? ISO 639 language descriptor ? */
#ifdef STATS
/* Stats */
/* XXX?? ...stats */
#endif
} pgrm_descriptor_t;
/*****************************************************************************
* pcr_descriptor_t
*****************************************************************************
* Contains informations used to synchronise the decoder with the server
*****************************************************************************/
typedef struct pcr_descriptor_struct
{
/* system_date = PTS_date + delta_pcr + delta_absolute */
mtime_t delta_pcr;
mtime_t delta_absolute;
mtime_t last_pcr;
u32 i_synchro_state;
count_t c_average_count;
/* counter used to compute dynamic average values */
} pcr_descriptor_t;
/*****************************************************************************
* stream_descriptor_t
*****************************************************************************
* Describes a transport stream and list its associated programs. Build upon
* the informations carried in program association sections
*****************************************************************************/
typedef struct
{
u16 i_stream_id; /* stream id */
/* Program Association Table status */
u8 i_PAT_version; /* version number */
boolean_t b_is_PAT_complete; /* Is the PAT complete ?*/
u8 i_known_PAT_sections;
/* Number of section we received so far */
byte_t a_known_PAT_sections[32];
/* Already received sections */
/* Program Map Table status */
boolean_t b_is_PMT_complete; /* Is the PMT complete ?*/
u8 i_known_PMT_sections;
/* Number of section we received so far */
byte_t a_known_PMT_sections[32];
/* Already received sections */
/* Service Description Table status */
u8 i_SDT_version; /* version number */
boolean_t b_is_SDT_complete; /* Is the SDT complete ?*/
u8 i_known_SDT_sections;
/* Number of section we received so far */
byte_t a_known_SDT_sections[32];
/* Already received sections */
/* Programs description */
int i_pgrm_number; /* Number of program number we have */
pgrm_descriptor_t ** ap_programs; /* Array of pointers to pgrm */
#ifdef STATS
/* Stats */
/* XXX?? ...stats */
#endif
} stream_descriptor_t;
/*****************************************************************************
* input_netlist_t
*****************************************************************************/
typedef struct
{
vlc_mutex_t lock; /* netlist modification lock */
struct iovec p_ts_free[INPUT_MAX_TS + INPUT_TS_READ_ONCE];
/* FIFO or LIFO of free TS packets */
ts_packet_t * p_ts_packets;
/* pointer to the first TS packet we allocated */
pes_packet_t * p_pes_free[INPUT_MAX_PES + 1];
/* FIFO or LIFO of free PES packets */
pes_packet_t * p_pes_packets;
/* pointer to the first PES packet we allocated */
/* To use the efficiency of the scatter/gather IO operations. We implemented
* it in 2 ways, as we don't know yet which one is better : as a FIFO (code
* simplier) or as a LIFO stack (when we doesn't care of the ordering, this
* allow to drastically improve the cache performance) */
#ifdef INPUT_LIFO_TS_NETLIST
int i_ts_index;
#else
int i_ts_start, i_ts_end;
#endif
#ifdef INPUT_LIFO_PES_NETLIST
int i_pes_index;
#else
int i_pes_start, i_pes_end;
#endif
} input_netlist_t;
/*****************************************************************************
* input_thread_t
*****************************************************************************
* This structure includes all the local static variables of an input thread,
* including the netlist and the ES descriptors
* Note that p_es must be defined as a static table, otherwise we would have to
* update all reference to it each time the table would be reallocated
*****************************************************************************/
/* Function pointers used in structure */
typedef int (input_open_t) ( p_input_thread_t p_input );
typedef int (input_read_t) ( p_input_thread_t p_input, const struct iovec *p_vector,
size_t i_count );
typedef void (input_close_t) ( p_input_thread_t p_input );
/* Structure */
typedef struct input_thread_s
{
/* Thread properties and locks */
boolean_t b_die; /* 'die' flag */
boolean_t b_error; /* deadlock */
vlc_thread_t thread_id; /* id for thread functions */
vlc_mutex_t programs_lock; /* programs modification lock */
vlc_mutex_t es_lock; /* es modification lock */
int * pi_status; /* temporary status flag */
/* Input method description */
int i_method; /* input method */
int i_handle; /* file/socket descriptor */
char * psz_source; /* source */
int i_port; /* port number */
int i_vlan; /* id for vlan method */
input_open_t * p_Open; /* opener of the method */
input_read_t * p_Read; /* reading function */
input_close_t * p_Close; /* destroying function */
/* General stream description */
stream_descriptor_t * p_stream; /* PAT tables */
es_descriptor_t p_es[INPUT_MAX_ES];/* carried elementary streams */
pcr_descriptor_t * p_pcr; /* PCR struct used for synchronisation */
/* List of streams to demux */
es_descriptor_t * pp_selected_es[INPUT_MAX_SELECTED_ES];
/* Netlists */
input_netlist_t netlist; /* see above */
/* Default settings for spawned decoders */
p_aout_thread_t p_aout; /* audio output thread structure */
p_vout_thread_t p_vout; /* video output thread */
#ifdef STATS
/* Statistics */
count_t c_loops; /* number of loops */
count_t c_bytes; /* bytes read */
count_t c_payload_bytes; /* payload useful bytes */
count_t c_packets_read; /* packets read */
count_t c_packets_trashed; /* trashed packets */
#endif
} input_thread_t;
/* Input methods */
#define INPUT_METHOD_NONE 0 /* input thread is inactive */
#define INPUT_METHOD_TS_FILE 10 /* TS stream is read from a file */
#define INPUT_METHOD_TS_UCAST 20 /* TS UDP unicast */
#define INPUT_METHOD_TS_MCAST 21 /* TS UDP multicast */
#define INPUT_METHOD_TS_BCAST 22 /* TS UDP broadcast */
#define INPUT_METHOD_TS_VLAN_BCAST 32 /* TS UDP broadcast with VLANs */
/*****************************************************************************
* Prototypes
*****************************************************************************/
input_thread_t *input_CreateThread ( int i_method, char *psz_source, int i_port,
int i_vlan, p_vout_thread_t p_vout,
p_aout_thread_t p_aout, int *pi_status );
void input_DestroyThread ( input_thread_t *p_input, int *pi_status );
int input_OpenAudioStream ( input_thread_t *p_input, int i_pid );
void input_CloseAudioStream ( input_thread_t *p_input, int i_pid );
int input_OpenVideoStream ( input_thread_t *p_input, int i_pid );
void input_CloseVideoStream ( input_thread_t *p_input, int i_pid );