Buffer source API

Files
file	buffersrc.h
	Memory buffer source API.

Enumerations
enum	{ AV_BUFFERSRC_FLAG_NO_CHECK_FORMAT = 1, AV_BUFFERSRC_FLAG_PUSH = 4, AV_BUFFERSRC_FLAG_KEEP_REF = 8 }

Functions
int	av_buffersrc_add_ref (AVFilterContext *buffer_src, AVFilterBufferRef *picref, int flags)
	Add buffer data in picref to buffer_src.
unsigned	av_buffersrc_get_nb_failed_requests (AVFilterContext *buffer_src)
	Get the number of failed requests.
int	av_buffersrc_write_frame (AVFilterContext *ctx, const AVFrame *frame)
	Add a frame to the buffer source.
int	av_buffersrc_add_frame (AVFilterContext *ctx, AVFrame *frame)
	Add a frame to the buffer source.
int	av_buffersrc_add_frame_flags (AVFilterContext *buffer_src, AVFrame *frame, int flags)
	Add a frame to the buffer source.

Detailed Description

Enumeration Type Documentation

anonymous enum

Enumerator:

AV_BUFFERSRC_FLAG_NO_CHECK_FORMAT	Do not check for format changes.
AV_BUFFERSRC_FLAG_PUSH	Immediately push the frame to the output.
AV_BUFFERSRC_FLAG_KEEP_REF	Keep a reference to the frame. If the frame if reference-counted, create a new reference; otherwise copy the frame data.

Definition at line 38 of file buffersrc.h.

Function Documentation

int av_buffersrc_add_ref	(	AVFilterContext *	buffer_src,
		AVFilterBufferRef *	picref,
		int	flags
	)

Add buffer data in picref to buffer_src.

Parameters

buffer_src	pointer to a buffer source context
picref	a buffer reference, or NULL to mark EOF
flags	a combination of AV_BUFFERSRC_FLAG_*

Returns

>= 0 in case of success, a negative AVERROR code in case of failure

Referenced by decode_audio(), decode_video(), and sub2video_flush().

unsigned av_buffersrc_get_nb_failed_requests

(

AVFilterContext *

buffer_src

)

Get the number of failed requests.

A failed request is when the request_frame method is called while no frame is present in the buffer. The number is reset when a frame is added.

Definition at line 327 of file buffersrc.c.

Referenced by sub2video_heartbeat(), and transcode_from_filter().

int av_buffersrc_write_frame	(	AVFilterContext *	ctx,
		const AVFrame *	frame
	)

Add a frame to the buffer source.

Parameters

ctx	an instance of the buffersrc filter
frame	frame to be added. If the frame is reference counted, this function will make a new reference to it. Otherwise the frame data will be copied.

Returns

0 on success, a negative AVERROR on error

This function is equivalent to av_buffersrc_add_frame_flags() with the AV_BUFFERSRC_FLAG_KEEP_REF flag.

Definition at line 80 of file buffersrc.c.

int av_buffersrc_add_frame	(	AVFilterContext *	ctx,
		AVFrame *	frame
	)

Add a frame to the buffer source.

Parameters

ctx	an instance of the buffersrc filter
frame	frame to be added. If the frame is reference counted, this function will take ownership of the reference(s) and reset the frame. Otherwise the frame data will be copied. If this function returns an error, the input frame is not touched.

Returns

0 on success, a negative AVERROR on error.

Note

the difference between this function and av_buffersrc_write_frame() is that av_buffersrc_write_frame() creates a new reference to the input frame, while this function takes ownership of the reference passed to it.

This function is equivalent to av_buffersrc_add_frame_flags() without the AV_BUFFERSRC_FLAG_KEEP_REF flag.

Definition at line 86 of file buffersrc.c.

Referenced by audio_decode_frame(), decode_audio(), decode_video(), main(), and video_thread().

int av_buffersrc_add_frame_flags	(	AVFilterContext *	buffer_src,
		AVFrame *	frame,
		int	flags
	)

Add a frame to the buffer source.

By default, if the frame is reference-counted, this function will take ownership of the reference(s) and reset the frame. This can be controlled using the flags.

If this function returns an error, the input frame is not touched.

Parameters

buffer_src	pointer to a buffer source context
frame	a frame, or NULL to mark EOF
flags	a combination of AV_BUFFERSRC_FLAG_*

Returns

>= 0 in case of success, a negative AVERROR code in case of failure

Definition at line 94 of file buffersrc.c.

Referenced by av_buffersrc_add_frame(), av_buffersrc_write_frame(), decode_video(), filter_encode_write_frame(), main(), and sub2video_push_ref().