unit ffm.avio; {$i ffmpeg.inc} interface uses ffm.log, ffm.ctypes; (* // * copyright (c) 2001 Fabrice Bellard // * // * This file is part of ffm. // * // * FFmpeg 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. // * // * FFmpeg 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 FFmpeg; if not, write to the Free Software // * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA *) // #ifndef AVFORMAT_AVIO_H // #define AVFORMAT_AVIO_H // (* // * @file // * @ingroup lavf_io // * Buffered I/O operations *) // // #include // // #include "libavutil/common.h" // #include "libavutil/dict.h" // #include "libavutil/log.h" // // #include "libavformat/version.h" // // // #define AVIO_SEEKABLE_NORMAL 0x0001 /**< Seeking works like for a local file */ // (* * Callback for checking whether to abort blocking functions. * AVERROR_EXIT is returned in this case by the interrupted * function. During blocking operations, callback is called with * opaque as parameter. If the callback returns 1, the * blocking operation will be aborted. * * No members can be added to this struct without a major bump, if * new elements have been added after this struct in AVFormatContext * or AVIOContext. *) Type TAVIOInterruptCB = record callback: function(param: Pointer): integer; cdecl; opaque: Pointer; end; (* // * 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() *) pAVIOContext = ^TAVIOContext; TAVIOContext = {packed} record (* * 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. *) av_class: pAVClass; buffer: pByte; // **< Start of the buffer. */ buffer_size: integer; // **< Maximum buffer size */ buf_ptr: pByte; // **< Current position in the buffer */ buf_end: pByte; // **< 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. */ opaque: Pointer; // **< A private pointer, passed to the read/write/seek/... // functions. */ // int (*read_packet)(void *opaque, uint8_t *buf, int buf_size); read_packet: function(opaque: Pointer; buf: pByte; buf_size: integer): integer; cdecl; // int (*write_packet)(void *opaque, uint8_t *buf, int buf_size); write_packet: function(opaque: Pointer; buf: pByte; buf_size: integer): integer; cdecl; // int64_t (*seek)(void *opaque, int64_t offset, int whence); seek: function(opaque: Pointer; offset: int64_t; whence: integer): int64_t; cdecl; pos: int64_t; // **< position in the file of the current buffer */ must_flush: integer; // **< true if the next seek should flush */ eof_reached: integer; // **< true if eof reached */ write_flag: integer; // **< true if open for writing */ max_packet_size: integer; checksum: culong; checksum_ptr: pByte; // unsigned long (*update_checksum)(unsigned long checksum, const uint8_t *buf, unsigned int size); update_checksum: function(checksum: culong; const buf: pByte; size: Cardinal): Cardinal; cdecl; error: integer; // **< contains the error code or 0 if no error happened */ (* * Pause or resume playback for network streaming protocols - e.g. MMS. *) // int (*read_pause)(void *opaque, int pause); read_pause: function(opaque: Pointer; pause: cint): cint; cdecl; (* * 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. *) // int64_t (*read_seek)(void *opaque, int stream_index, int64_t timestamp, int flags); read_seek: function(opaque: Pointer; stream_index: cint; timestamp: cint64; flags: cint): cint64; cdecl; (* * A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable. *) seekable: integer; (* * max filesize, used to limit allocations * This field is internal to libavformat and access from outside is not allowed. *) maxsize: int64_t; (* * 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. *) direct: integer; (* * Bytes read statistic * This field is internal to libavformat and access from outside is not allowed. *) bytes_read: int64_t; (* * seek statistic * This field is internal to libavformat and access from outside is not allowed. *) seek_count: integer; (* * writeout statistic * This field is internal to libavformat and access from outside is not allowed. *) writeout_count: integer; end; /// * unbuffered I/O */ // (* // * Return AVIO_FLAG_* access flags corresponding to the access permissions // * of the resource in url, or a negative value corresponding to an // * AVERROR code in case of failure. The returned access flags are // * masked by the value in flags. // * // * @note This function is intrinsically unsafe, in the sense that the // * checked resource may change its existence or permission status from // * one call to another. Thus you should not trust the returned value, // * unless you are sure that no other processes are accessing the // * checked resource. *) // int avio_check(const char *url, int flags); // (* // * Allocate and initialize an AVIOContext for buffered I/O. It must be later // * freed with av_free(). // * // * @param buffer Memory block for input/output operations via AVIOContext. // * The buffer must be allocated with av_malloc() and friends. // * @param buffer_size The buffer size is very important for performance. // * For protocols with fixed blocksize it should be set to this blocksize. // * For others a typical size is a cache page, e.g. 4kb. // * @param write_flag Set to 1 if the buffer should be writable, 0 otherwise. // * @param opaque An opaque pointer to user-specific data. // * @param read_packet A function for refilling the buffer, may be NULL. // * @param write_packet A function for writing the buffer contents, may be NULL. // * The function may not change the input buffers content. // * @param seek A function for seeking to specified byte position, may be NULL. // * // * @return Allocated AVIOContext or NULL on failure. *) // AVIOContext *avio_alloc_context( // unsigned char *buffer, // int buffer_size, // int write_flag, // void *opaque, // 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)); // // void avio_w8(AVIOContext *s, int b); // void avio_write(AVIOContext *s, const unsigned char *buf, int size); // void avio_wl64(AVIOContext *s, uint64_t val); // void avio_wb64(AVIOContext *s, uint64_t val); // void avio_wl32(AVIOContext *s, unsigned int val); // void avio_wb32(AVIOContext *s, unsigned int val); // void avio_wl24(AVIOContext *s, unsigned int val); // void avio_wb24(AVIOContext *s, unsigned int val); // void avio_wl16(AVIOContext *s, unsigned int val); // void avio_wb16(AVIOContext *s, unsigned int val); // (* // * Write a NULL-terminated string. // * @return number of bytes written. *) // int avio_put_str(AVIOContext *s, const char *str); // (* // * Convert an UTF-8 string to UTF-16LE and write it. // * @return number of bytes written. *) // int avio_put_str16le(AVIOContext *s, const char *str); // (* // * Passing this as the "whence" parameter to a seek function causes it to // * return the filesize without seeking anywhere. Supporting this is optional. // * If it is not supported then the seek function will return <0. *) // #define AVSEEK_SIZE 0x10000 // (* // * Oring this flag as into the "whence" parameter to a seek function causes it to // * seek by any means (like reopening and linear reading) or other normally unreasonable // * means that can be extremely slow. // * This may be ignored by the seek code. *) // #define AVSEEK_FORCE 0x20000 // (* // * fseek() equivalent for AVIOContext. // * @return new position or AVERROR. *) // int64_t avio_seek(AVIOContext *s, int64_t offset, int whence); // (* // * Skip given number of bytes forward // * @return new position or AVERROR. *) // int64_t avio_skip(AVIOContext *s, int64_t offset); // (* // * ftell() equivalent for AVIOContext. // * @return position or AVERROR. *) // static av_always_inline int64_t avio_tell(AVIOContext *s) // { // return avio_seek(s, 0, SEEK_CUR); // } // (* // * Get the filesize. // * @return filesize or AVERROR *) // int64_t avio_size(AVIOContext *s); // (* // * feof() equivalent for AVIOContext. // * @return non zero if and only if end of file *) // int url_feof(AVIOContext *s); // (*@warning currently size is limited */ // int avio_printf(AVIOContext *s, const char *fmt, ...) av_printf_format(2, 3); // (* // * Force flushing of buffered data to the output s. // * // * Force the buffered data to be immediately written to the output, // * without to wait to fill the internal buffer. *) // void avio_flush(AVIOContext *s); // (* // * Read size bytes from AVIOContext into buf. // * @return number of bytes read or AVERROR *) // int avio_read(AVIOContext *s, unsigned char *buf, int size); // (* // * @name Functions for reading from AVIOContext // * @{ // * // * @note return 0 if EOF, so you cannot use it if EOF handling is // * necessary *) // int avio_r8 (AVIOContext *s); // unsigned int avio_rl16(AVIOContext *s); // unsigned int avio_rl24(AVIOContext *s); // unsigned int avio_rl32(AVIOContext *s); // uint64_t avio_rl64(AVIOContext *s); // unsigned int avio_rb16(AVIOContext *s); // unsigned int avio_rb24(AVIOContext *s); // unsigned int avio_rb32(AVIOContext *s); // uint64_t avio_rb64(AVIOContext *s); (* // * @} *) // (* // * Read a string from pb into buf. The reading will terminate when either // * a NULL character was encountered, maxlen bytes have been read, or nothing // * more can be read from pb. The result is guaranteed to be NULL-terminated, it // * will be truncated if buf is too small. // * Note that the string is not interpreted or validated in any way, it // * might get truncated in the middle of a sequence for multi-byte encodings. // * // * @return number of bytes read (is always <= maxlen). // * If reading ends on EOF or error, the return value will be one more than // * bytes actually read. *) // int avio_get_str(AVIOContext *pb, int maxlen, char *buf, int buflen); // (* // * Read a UTF-16 string from pb and convert it to UTF-8. // * The reading will terminate when either a null or invalid character was // * encountered or maxlen bytes have been read. // * @return number of bytes read (is always <= maxlen) *) // int avio_get_str16le(AVIOContext *pb, int maxlen, char *buf, int buflen); // int avio_get_str16be(AVIOContext *pb, int maxlen, char *buf, int buflen); // // (* // * @name URL open modes // * The flags argument to avio_open must be one of the following // * constants, optionally ORed with other flags. // * @{ *) const AVIO_FLAG_READ = 1; // read-only AVIO_FLAG_WRITE = 2; // write-only AVIO_FLAG_READ_WRITE = AVIO_FLAG_READ or AVIO_FLAG_WRITE; // read-write pseudo flag (* // * @} *) // (* * Use non-blocking mode. * If this flag is set, operations on the context will return * AVERROR(EAGAIN) if they can not be performed immediately. * If this flag is not set, operations on the context will never return * AVERROR(EAGAIN). * Note that this flag does not affect the opening/connecting of the * context. Connecting a protocol will always block if necessary (e.g. on * network protocols) but never hang (e.g. on busy devices). * Warning: non-blocking protocols is work-in-progress; this flag may be * silently ignored. *) const AVIO_FLAG_NONBLOCK = 8; (* * Use direct mode. * 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. *) AVIO_FLAG_DIRECT = $8000; (* // * Create and initialize a AVIOContext for accessing the // * resource indicated by url. // * @note When the resource indicated by url has been opened in // * read+write mode, the AVIOContext can be used only for writing. // * // * @param s Used to return the pointer to the created AVIOContext. // * In case of failure the pointed to value is set to NULL. // * @param flags flags which control how the resource indicated by url // * is to be opened // * @return >= 0 in case of success, a negative value corresponding to an // * AVERROR code in case of failure *) // int avio_open(AVIOContext **s, const char *url, int flags); function avio_open(Var s: pAVIOContext; const url: pAnsiChar; flags: integer): integer; cdecl; (* // * Create and initialize a AVIOContext for accessing the // * resource indicated by url. // * @note When the resource indicated by url has been opened in // * read+write mode, the AVIOContext can be used only for writing. // * // * @param s Used to return the pointer to the created AVIOContext. // * In case of failure the pointed to value is set to NULL. // * @param flags flags which control how the resource indicated by url // * is to be opened // * @param int_cb an interrupt callback to be used at the protocols level // * @param options A dictionary filled with protocol-private options. On return // * this parameter will be destroyed and replaced with a dict containing options // * that were not found. May be NULL. // * @return >= 0 in case of success, a negative value corresponding to an // * AVERROR code in case of failure *) // int avio_open2(AVIOContext **s, const char *url, int flags, // const AVIOInterruptCB *int_cb, AVDictionary **options); // (* // * Close the resource accessed by the AVIOContext s and free it. // * This function can only be used if s was opened by avio_open(). // * // * The internal buffer is automatically flushed before closing the // * resource. // * // * @return 0 on success, an AVERROR < 0 on error. // * @see avio_closep *) // int avio_close(AVIOContext *s); function avio_close(s: pAVIOContext): integer; (* // * Close the resource accessed by the AVIOContext *s, free it // * and set the pointer pointing to it to NULL. // * This function can only be used if s was opened by avio_open(). // * // * The internal buffer is automatically flushed before closing the // * resource. // * // * @return 0 on success, an AVERROR < 0 on error. // * @see avio_close *) // int avio_closep(AVIOContext **s); // // (* // * Open a write only memory stream. // * // * @param s new IO context // * @return zero if no error. *) // int avio_open_dyn_buf(AVIOContext **s); // (* // * Return the written size and a pointer to the buffer. The buffer // * must be freed with av_free(). // * Padding of FF_INPUT_BUFFER_PADDING_SIZE is added to the buffer. // * // * @param s IO context // * @param pbuffer pointer to a byte buffer // * @return the length of the byte buffer *) // int avio_close_dyn_buf(AVIOContext *s, uint8_t **pbuffer); // (* // * Iterate through names of available protocols. // * // * @param opaque A private pointer representing current protocol. // * It must be a pointer to NULL on first iteration and will // * be updated by successive calls to avio_enum_protocols. // * @param output If set to 1, iterate over output protocols, // * otherwise over input protocols. // * // * @return A static string containing the name of current protocol or NULL *) // const char *avio_enum_protocols(void **opaque, int output); // (* // * Pause and resume playing - only meaningful if using a network streaming // * protocol (e.g. MMS). // * @param pause 1 for pause, 0 for resume *) // int avio_pause(AVIOContext *h, int pause); // (* // * Seek to a given timestamp relative to some component stream. // * Only meaningful if using a network streaming protocol (e.g. MMS.). // * @param stream_index The stream index that the timestamp is relative to. // * If stream_index is (-1) the timestamp should be in AV_TIME_BASE // * units from the beginning of the presentation. // * If a stream_index >= 0 is used and the protocol does not support // * seeking based on component streams, the call will fail. // * @param timestamp timestamp in AVStream.time_base units // * or if there is no stream specified then in AV_TIME_BASE units. // * @param flags Optional combination of AVSEEK_FLAG_BACKWARD, AVSEEK_FLAG_BYTE // * and AVSEEK_FLAG_ANY. The protocol may silently ignore // * AVSEEK_FLAG_BACKWARD and AVSEEK_FLAG_ANY, but AVSEEK_FLAG_BYTE will // * fail if used and not supported. // * @return >= 0 on success // * @see AVInputFormat::read_seek *) // int64_t avio_seek_time(AVIOContext *h, int stream_index, // int64_t timestamp, int flags); implementation uses ffm.lib; function avio_open; external avio_dll; function avio_close; external avio_dll; end.