FFmpeg  4.0
Data Fields
AVIOContext Struct Reference

Bytestream IO Context. More...

#include <libavformat/avio.h>

Data Fields

const AVClassav_class
 A class for private options. More...
 
unsigned char * buffer
 Start of the buffer. More...
 
int buffer_size
 Maximum buffer size. More...
 
unsigned char * buf_ptr
 Current position in the buffer. More...
 
unsigned char * buf_end
 End of the data, may be less than buffer+buffer_size if the read function returned less data than requested, e.g. More...
 
voidopaque
 A private pointer, passed to the read/write/seek/... More...
 
int(* read_packet )(void *opaque, uint8_t *buf, int buf_size)
 
int(* write_packet )(void *opaque, uint8_t *buf, int buf_size)
 
int64_t(* seek )(void *opaque, int64_t offset, int whence)
 
int64_t pos
 position in the file of the current buffer More...
 
int eof_reached
 true if eof reached More...
 
int write_flag
 true if open for writing More...
 
int max_packet_size
 
unsigned long checksum
 
unsigned char * checksum_ptr
 
unsigned long(* update_checksum )(unsigned long checksum, const uint8_t *buf, unsigned int size)
 
int error
 contains the error code or 0 if no error happened More...
 
int(* read_pause )(void *opaque, int pause)
 Pause or resume playback for network streaming protocols - e.g. More...
 
int64_t(* read_seek )(void *opaque, int stream_index, int64_t timestamp, int flags)
 Seek to a given timestamp in stream with the specified stream_index. More...
 
int seekable
 A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable. More...
 
int64_t maxsize
 max filesize, used to limit allocations This field is internal to libavformat and access from outside is not allowed. More...
 
int direct
 avio_read and avio_write should if possible be satisfied directly instead of going through a buffer, and avio_seek will always call the underlying seek function directly. More...
 
int64_t bytes_read
 Bytes read statistic This field is internal to libavformat and access from outside is not allowed. More...
 
int seek_count
 seek statistic This field is internal to libavformat and access from outside is not allowed. More...
 
int writeout_count
 writeout statistic This field is internal to libavformat and access from outside is not allowed. More...
 
int orig_buffer_size
 Original buffer size used internally after probing and ensure seekback to reset the buffer size This field is internal to libavformat and access from outside is not allowed. More...
 
int short_seek_threshold
 Threshold to favor readahead over seek. More...
 
const char * protocol_whitelist
 ',' separated list of allowed protocols. More...
 
const char * protocol_blacklist
 ',' separated list of disallowed protocols. More...
 
int(* write_data_type )(void *opaque, uint8_t *buf, int buf_size, enum AVIODataMarkerType type, int64_t time)
 A callback that is used instead of write_packet. More...
 
int ignore_boundary_point
 If set, don't call write_data_type separately for AVIO_DATA_MARKER_BOUNDARY_POINT, but ignore them and treat them as AVIO_DATA_MARKER_UNKNOWN (to avoid needlessly small chunks of data returned from the callback). More...
 
enum AVIODataMarkerType current_type
 Internal, not meant to be used from outside of AVIOContext. More...
 
int64_t last_time
 
int(* short_seek_get )(void *opaque)
 A callback that is used instead of short_seek_threshold. More...
 
int64_t written
 
unsigned char * buf_ptr_max
 Maximum reached position before a backward seek in the write buffer, used keeping track of already written data for a later flush. More...
 
int min_packet_size
 Try to buffer at least this amount of data before flushing it. More...
 

Detailed Description

Bytestream IO Context.

New fields can be added to the end with minor version bumps. Removal, reordering and changes to existing fields require a major version bump. sizeof(AVIOContext) must not be used outside libav*.

Note
None of the function pointers in AVIOContext should be called directly, they should only be set by the client application when implementing custom I/O. Normally these are set to the function pointers specified in avio_alloc_context()
Examples:
avio_reading.c, http_multiclient.c, qsvdec.c, and transcode_aac.c.

Definition at line 161 of file avio.h.

Field Documentation

◆ av_class

const AVClass* AVIOContext::av_class

A class for private options.

If this AVIOContext is created by avio_open2(), av_class is set and passes the options down to protocols.

If this AVIOContext is manually allocated, then av_class may be set by the caller.

warning – this field can be NULL, be sure to not pass this AVIOContext to any av_opt_* functions in that case.

Definition at line 174 of file avio.h.

Referenced by av_probe_input_buffer2(), and format_child_next().

◆ buffer

unsigned char* AVIOContext::buffer

◆ buffer_size

int AVIOContext::buffer_size

◆ buf_ptr

unsigned char* AVIOContext::buf_ptr

◆ buf_end

unsigned char* AVIOContext::buf_end

End of the data, may be less than buffer+buffer_size if the read function returned less data than requested, e.g.

for streams where no more data has been received yet.

Definition at line 229 of file avio.h.

Referenced by avio_r8(), avio_read(), avio_read_partial(), avio_seek(), avio_seek_time(), avio_w8(), avio_write(), ffio_ensure_seekback(), ffio_fill(), ffio_init_context(), ffio_read_indirect(), ffio_rewind_with_probe_data(), fill_buffer(), flush_buffer(), hls_read_seek(), init_packetizer(), read_gab2_sub(), and url_resetbuf().

◆ opaque

void* AVIOContext::opaque

◆ read_packet

int(* AVIOContext::read_packet) (void *opaque, uint8_t *buf, int buf_size)

◆ write_packet

int(* AVIOContext::write_packet) (void *opaque, uint8_t *buf, int buf_size)

Definition at line 236 of file avio.h.

Referenced by ffio_init_context(), ffio_open_null_buf(), and writeout().

◆ seek

int64_t(* AVIOContext::seek) (void *opaque, int64_t offset, int whence)

Definition at line 237 of file avio.h.

Referenced by avio_seek(), avio_seek_time(), avio_size(), and ffio_init_context().

◆ pos

int64_t AVIOContext::pos

◆ eof_reached

int AVIOContext::eof_reached

◆ write_flag

int AVIOContext::write_flag

◆ max_packet_size

int AVIOContext::max_packet_size

◆ checksum

unsigned long AVIOContext::checksum

Definition at line 242 of file avio.h.

Referenced by ffio_get_checksum(), ffio_init_checksum(), fill_buffer(), and flush_buffer().

◆ checksum_ptr

unsigned char* AVIOContext::checksum_ptr

◆ update_checksum

unsigned long(* AVIOContext::update_checksum) (unsigned long checksum, const uint8_t *buf, unsigned int size)

◆ error

int AVIOContext::error

◆ read_pause

int(* AVIOContext::read_pause) (void *opaque, int pause)

Pause or resume playback for network streaming protocols - e.g.

MMS.

Definition at line 249 of file avio.h.

Referenced by avio_pause(), and ffio_init_context().

◆ read_seek

int64_t(* AVIOContext::read_seek) (void *opaque, int stream_index, int64_t timestamp, int flags)

Seek to a given timestamp in stream with the specified stream_index.

Needed for some network streaming protocols which don't support seeking to byte position.

Definition at line 255 of file avio.h.

Referenced by avio_seek_time(), and ffio_init_context().

◆ seekable

int AVIOContext::seekable

A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable.

Definition at line 260 of file avio.h.

Referenced by adp_read_header(), adts_aac_read_header(), aiff_read_header(), aiff_write_trailer(), amf_parse_object(), ape_read_header(), apng_write_trailer(), asf_read_data(), asf_read_header(), asf_write_header1(), asf_write_trailer(), ast_write_trailer(), avi_read_header(), avi_write_header(), avi_write_idx1(), avi_write_ix(), avi_write_packet(), avi_write_packet_internal(), avi_write_trailer(), avio_seek(), caf_write_header(), caf_write_trailer(), check_keyboard_interaction(), cine_read_seek(), dsf_read_header(), dtshd_read_header(), dv_read_header(), end_ebml_master_crc32(), end_ebml_master_crc32_preliminary(), estimate_timings(), ff_id3v1_read(), ff_voc_get_packet(), ffio_init_context(), flac_write_trailer(), flv_read_packet(), flv_write_header(), force_one_stream(), get_aac_sample_rates(), gxf_write_header(), hls_read_header(), ico_write_header(), init_stream(), ivf_write_trailer(), matroska_execute_seekhead(), mkv_check_new_extra_data(), mkv_start_new_cluster(), mkv_write_flush_packet(), mkv_write_header(), mkv_write_packet_internal(), mkv_write_tags(), mkv_write_tracks(), mkv_write_trailer(), mmf_rate(), mov_find_next_sample(), mov_init(), mov_read_cmov(), mov_read_default(), mov_read_header(), mov_read_moof(), mp3_read_header(), mp3_write_xing(), mpc8_read_header(), mpc_read_header(), mpegps_read_pes_header(), mv_read_packet(), mv_read_seek(), mxf_parse_handle_essence(), mxf_read_random_index_pack(), mxf_write_footer(), nut_read_header(), ogg_get_length(), ogg_read_page(), ogg_replace_stream(), put_id3v2_tags(), r3d_read_header(), read_header(), read_seek(), reopen_demux_for_component(), rm_read_header(), rm_write_trailer(), rsd_read_header(), rso_write_header(), rv10_write_header(), seek_back(), seg_init(), seg_write_header(), segment_start(), set_spdif(), smjpeg_write_trailer(), sox_write_trailer(), start_ebml_master_crc32(), swf_write_trailer(), tak_read_header(), tta_read_header(), vc1test_write_trailer(), webm_chunk_write_header(), wv_read_block_header(), wv_read_header(), and wv_write_trailer().

◆ maxsize

int64_t AVIOContext::maxsize

max filesize, used to limit allocations This field is internal to libavformat and access from outside is not allowed.

Definition at line 266 of file avio.h.

Referenced by append_packet_chunked(), ffio_limit(), mp3_read_header(), and thp_read_header().

◆ direct

int AVIOContext::direct

avio_read and avio_write should if possible be satisfied directly instead of going through a buffer, and avio_seek will always call the underlying seek function directly.

Definition at line 273 of file avio.h.

Referenced by avio_read(), avio_seek(), avio_write(), and ffio_init_context().

◆ bytes_read

int64_t AVIOContext::bytes_read

Bytes read statistic This field is internal to libavformat and access from outside is not allowed.

Definition at line 279 of file avio.h.

Referenced by avformat_find_stream_info(), avio_close(), avio_read(), and fill_buffer().

◆ seek_count

int AVIOContext::seek_count

seek statistic This field is internal to libavformat and access from outside is not allowed.

Definition at line 285 of file avio.h.

Referenced by avformat_find_stream_info(), avio_close(), and avio_seek().

◆ writeout_count

int AVIOContext::writeout_count

writeout statistic This field is internal to libavformat and access from outside is not allowed.

Definition at line 291 of file avio.h.

Referenced by avio_close(), and writeout().

◆ orig_buffer_size

int AVIOContext::orig_buffer_size

Original buffer size used internally after probing and ensure seekback to reset the buffer size This field is internal to libavformat and access from outside is not allowed.

Definition at line 298 of file avio.h.

Referenced by ffio_init_context(), ffio_set_buf_size(), and fill_buffer().

◆ short_seek_threshold

int AVIOContext::short_seek_threshold

Threshold to favor readahead over seek.

This is current internal only, do not use from outside.

Definition at line 304 of file avio.h.

Referenced by avio_seek(), ff_configure_buffers_for_index(), and ffio_init_context().

◆ protocol_whitelist

const char* AVIOContext::protocol_whitelist

',' separated list of allowed protocols.

Definition at line 309 of file avio.h.

Referenced by avformat_open_input().

◆ protocol_blacklist

const char* AVIOContext::protocol_blacklist

',' separated list of disallowed protocols.

Definition at line 314 of file avio.h.

Referenced by avformat_open_input().

◆ write_data_type

int(* AVIOContext::write_data_type) (void *opaque, uint8_t *buf, int buf_size, enum AVIODataMarkerType type, int64_t time)

A callback that is used instead of write_packet.

Definition at line 319 of file avio.h.

Referenced by avio_write_marker(), ffio_init_context(), init_fps(), and writeout().

◆ ignore_boundary_point

int AVIOContext::ignore_boundary_point

If set, don't call write_data_type separately for AVIO_DATA_MARKER_BOUNDARY_POINT, but ignore them and treat them as AVIO_DATA_MARKER_UNKNOWN (to avoid needlessly small chunks of data returned from the callback).

Definition at line 326 of file avio.h.

Referenced by avio_write_marker(), and ffio_init_context().

◆ current_type

enum AVIODataMarkerType AVIOContext::current_type

Internal, not meant to be used from outside of AVIOContext.

Definition at line 331 of file avio.h.

Referenced by avio_write_marker(), ffio_init_context(), and writeout().

◆ last_time

int64_t AVIOContext::last_time

Definition at line 332 of file avio.h.

Referenced by avio_write_marker(), ffio_init_context(), and writeout().

◆ short_seek_get

int(* AVIOContext::short_seek_get) (void *opaque)

A callback that is used instead of short_seek_threshold.

This is current internal only, do not use from outside.

Definition at line 338 of file avio.h.

Referenced by avio_seek(), and ffio_init_context().

◆ written

int64_t AVIOContext::written

Definition at line 340 of file avio.h.

Referenced by avio_size(), ffio_init_context(), and writeout().

◆ buf_ptr_max

unsigned char* AVIOContext::buf_ptr_max

Maximum reached position before a backward seek in the write buffer, used keeping track of already written data for a later flush.

Definition at line 346 of file avio.h.

Referenced by avio_flush(), avio_seek(), ffio_init_context(), ffio_set_buf_size(), and flush_buffer().

◆ min_packet_size

int AVIOContext::min_packet_size

Try to buffer at least this amount of data before flushing it.

Definition at line 351 of file avio.h.

Referenced by avio_write_marker(), and ffio_init_context().


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