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authorIvan Schreter <schreter@gmx.net>2009-09-05 19:31:01 +0000
committerIvan Schreter <schreter@gmx.net>2009-09-05 19:31:01 +0000
commit7a656933c91809dc8b2ec73bade826a76a58a304 (patch)
tree284d94fc1ed6d077efb493359cdd1c842c54dd57 /libavformat/seek.h
parent64b8e620cbbe3d2f726ccfa80323876b8f8bfc5c (diff)
cosmetic changes (indentation, doxygen comments, braces, put structures for API to header, ...)
Originally committed as revision 19773 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavformat/seek.h')
-rw-r--r--libavformat/seek.h93
1 files changed, 61 insertions, 32 deletions
diff --git a/libavformat/seek.h b/libavformat/seek.h
index 570c2bcedf..408f7d6ac7 100644
--- a/libavformat/seek.h
+++ b/libavformat/seek.h
@@ -1,5 +1,5 @@
/*
- * Utility functions for seeking for use within FFmpeg format handlers.
+ * seek utility functions for use within format handlers
*
* Copyright (c) 2009 Ivan Schreter
*
@@ -25,30 +25,59 @@
#include "avformat.h"
-/// Opaque structure for parser state.
-typedef struct AVParserState AVParserState;
+/**
+ * structure to store parser state of one AVStream
+ */
+typedef struct AVParserStreamState {
+ // saved members of AVStream
+ AVCodecParserContext *parser;
+ AVPacket cur_pkt;
+ int64_t last_IP_pts;
+ int64_t cur_dts;
+ int64_t reference_dts;
+ const uint8_t *cur_ptr;
+ int cur_len;
+ int probe_packets;
+} AVParserStreamState;
+
+/**
+ * structure to store parser state of AVFormat
+ */
+typedef struct AVParserState {
+ int64_t fpos; ///< file position at the time of call
+
+ // saved members of AVFormatContext
+ AVStream *cur_st; ///< current stream.
+ AVPacketList *packet_buffer; ///< packet buffer of original state
+ AVPacketList *raw_packet_buffer; ///< raw packet buffer of original state
+ int raw_packet_buffer_remaining_size; ///< remaining space in raw_packet_buffer
+
+ // saved info for streams
+ int nb_streams; ///< number of streams with stored state
+ AVParserStreamState *stream_states; ///< states of individual streams (array)
+} AVParserState;
/**
- * Search for sync point of all active streams.
+ * Search for the sync point of all active streams.
*
- * This is not supposed to be called directly by a user application,
+ * This routine is not supposed to be called directly by a user application,
* but by demuxers.
*
- * A sync point is a point in stream, so that decoding from this point,
- * output of decoders of all streams synchronizes closest to given timestamp
- * ts (but taking timestamp limits into account, i.e., no sooner than ts_min
- * and no later than ts_max).
+ * A sync point is defined as a point in stream, such that, when decoding start
+ * from this point, the decoded output of all streams synchronizes closest
+ * to the given timestamp ts. This routine also takes timestamp limits into account.
+ * Thus, the output will synchronize no sooner than ts_min and no later than ts_max.
*
- * @param stream_index stream index for time base reference of timestamps.
- * @param pos approximate position where to start searching for key frames.
- * @param min_ts minimum allowed timestamp (position, if AVSEEK_FLAG_BYTE set).
- * @param ts target timestamp (or position, if AVSEEK_FLAG_BYTE set in flags).
- * @param max_ts maximum allowed timestamp (position, if AVSEEK_FLAG_BYTE set).
- * @param flags if AVSEEK_FLAG_ANY is set, seek to any frame, otherwise only
- * to a keyframe. If AVSEEK_FLAG_BYTE is set, search by
- * position, not by timestamp.
- * @return < 0 if no such sync point could be found, otherwise stream position
- * (stream is repositioned to this position).
+ * @param stream_index stream index for time base reference of timestamps
+ * @param pos approximate position where to start searching for key frames
+ * @param min_ts minimum allowed timestamp (position, if AVSEEK_FLAG_BYTE set)
+ * @param ts target timestamp (or position, if AVSEEK_FLAG_BYTE set in flags)
+ * @param max_ts maximum allowed timestamp (position, if AVSEEK_FLAG_BYTE set)
+ * @param flags if AVSEEK_FLAG_ANY is set, seek to any frame, otherwise only
+ * to a keyframe. If AVSEEK_FLAG_BYTE is set, search by
+ * position, not by timestamp.
+ * @return -1 if no such sync point could be found, otherwise stream position
+ * (stream is repositioned to this position)
*/
int64_t ff_gen_syncpoint_search(AVFormatContext *s,
int stream_index,
@@ -61,16 +90,16 @@ int64_t ff_gen_syncpoint_search(AVFormatContext *s,
/**
* Store current parser state and file position.
*
- * This function can be used by demuxers before destructive seeking algorithm
- * to store parser state. After the seek, depending on outcome, original state
- * can be restored or new state kept and original state freed.
+ * This function can be used by demuxers before a destructive seeking algorithm
+ * to store the parser state. Depending on the outcome of the seek, either the original
+ * state can be restored or the new state kept and the original state freed.
*
- * @note As a side effect, original parser state is reset, since structures
- * are relinked to stored state instead of being deeply-copied (for
- * performance reasons and to keep code simple).
+ * @note As a side effect, the original parser state is reset, since structures
+ * are relinked to the stored state instead of being deeply-copied (for
+ * performance reasons and to keep the code simple).
*
- * @param s context from which to save state.
- * @return parser state object or NULL if memory could not be allocated.
+ * @param s context from which to save state
+ * @return parser state object or NULL if memory could not be allocated
*/
AVParserState *ff_store_parser_state(AVFormatContext *s);
@@ -78,19 +107,19 @@ AVParserState *ff_store_parser_state(AVFormatContext *s);
* Restore previously saved parser state and file position.
*
* Saved state will be invalidated and freed by this call, since internal
- * structures will be relinked back to stored state instead of being
+ * structures will be relinked back to the stored state instead of being
* deeply-copied.
*
- * @param s context to which to restore state (same as used for storing state).
- * @param state state to restore.
+ * @param s context to which to restore state (same as used for storing state)
+ * @param state state to restore
*/
void ff_restore_parser_state(AVFormatContext *s, AVParserState *state);
/**
* Free previously saved parser state.
*
- * @param s context to which the state belongs (same as used for storing state).
- * @param state state to free.
+ * @param s context to which the state belongs (same as used for storing state)
+ * @param state state to free
*/
void ff_free_parser_state(AVFormatContext *s, AVParserState *state);