pthread_frame.c File Reference

Frame multithreading support functions. More...

#include "config.h"
#include <stdatomic.h>
#include <stdint.h>
#include "avcodec.h"
#include "hwaccel.h"
#include "internal.h"
#include "pthread_internal.h"
#include "thread.h"
#include "version.h"
#include "libavutil/avassert.h"
#include "libavutil/buffer.h"
#include "libavutil/common.h"
#include "libavutil/cpu.h"
#include "libavutil/frame.h"
#include "libavutil/internal.h"
#include "libavutil/log.h"
#include "libavutil/mem.h"
#include "libavutil/opt.h"
#include "libavutil/thread.h"

Classes
struct	PerThreadContext
	Context used by codec threads and stored in their AVCodecInternal thread_ctx. More...
struct	FrameThreadContext
	Context stored in the client AVCodecInternal thread_ctx. More...

Macros
#define	THREAD_SAFE_CALLBACKS(avctx)   ((avctx)->thread_safe_callbacks || (avctx)->get_buffer2 == avcodec_default_get_buffer2)
#define	copy_fields(s, e)   memcpy(&dst->s, &src->s, (char*)&dst->e - (char*)&dst->s);

Typedefs
typedef struct PerThreadContext	PerThreadContext
	Context used by codec threads and stored in their AVCodecInternal thread_ctx.
typedef struct FrameThreadContext	FrameThreadContext
	Context stored in the client AVCodecInternal thread_ctx.

Enumerations
enum	{   STATE_INPUT_READY, STATE_SETTING_UP, STATE_GET_BUFFER, STATE_GET_FORMAT,   STATE_SETUP_FINISHED }

Functions
int	ff_thread_decode_frame (AVCodecContext *avctx, AVFrame *picture, int *got_picture_ptr, AVPacket *avpkt)
	Submit a new frame to a decoding thread. More...
void	ff_thread_report_progress (ThreadFrame *f, int n, int field)
	Notify later decoding threads when part of their reference picture is ready. More...
void	ff_thread_await_progress (ThreadFrame *f, int n, int field)
	Wait for earlier decoding threads to finish reference pictures. More...
void	ff_thread_finish_setup (AVCodecContext *avctx)
	If the codec defines update_thread_context(), call this when they are ready for the next thread to start decoding the next frame. More...
void	ff_frame_thread_free (AVCodecContext *avctx, int thread_count)
int	ff_frame_thread_init (AVCodecContext *avctx)
void	ff_thread_flush (AVCodecContext *avctx)
	Wait for decoding threads to finish and reset internal state. More...
int	ff_thread_can_start_frame (AVCodecContext *avctx)
enum AVPixelFormat	ff_thread_get_format (AVCodecContext *avctx, const enum AVPixelFormat *fmt)
	Wrapper around get_format() for frame-multithreaded codecs. More...
int	ff_thread_get_buffer (AVCodecContext *avctx, ThreadFrame *f, int flags)
	Wrapper around get_buffer() for frame-multithreaded codecs. More...
void	ff_thread_release_buffer (AVCodecContext *avctx, ThreadFrame *f)
	Wrapper around release_buffer() frame-for multithreaded codecs. More...

Detailed Description

Frame multithreading support functions.

See also

doc/multithreading.txt

Enumeration Type Documentation

anonymous enum

anonymous enum

Enumerator
STATE_INPUT_READY	Set when the thread is awaiting a packet. Set before the codec has called ff_thread_finish_setup().
STATE_GET_BUFFER	Set when the codec calls get_buffer(). State is returned to STATE_SETTING_UP afterwards.
STATE_GET_FORMAT	Set when the codec calls get_format(). State is returned to STATE_SETTING_UP afterwards.Set after the codec has called ff_thread_finish_setup().

Function Documentation

ff_thread_await_progress()

void ff_thread_await_progress	(	ThreadFrame *	f,
		int	progress,
		int	field
	)

Wait for earlier decoding threads to finish reference pictures.

Call this before accessing some part of a picture, with a given value for progress, and it will return after the responsible decoding thread calls ff_thread_report_progress() with the same or higher value for progress.

Parameters

f	The picture being referenced.
progress	Value, in arbitrary units, to wait for.
field	The field being referenced, for field-picture codecs. 0 for top field or frame pictures, 1 for bottom field.

ff_thread_decode_frame()

int ff_thread_decode_frame	(	AVCodecContext *	avctx,
		AVFrame *	picture,
		int *	got_picture_ptr,
		AVPacket *	avpkt
	)

Submit a new frame to a decoding thread.

Returns the next available frame in picture. *got_picture_ptr will be 0 if none is available. The return value on success is the size of the consumed packet for compatibility with avcodec_decode_video2(). This means the decoder has to consume the full packet.

Parameters are the same as avcodec_decode_video2().

ff_thread_finish_setup()

void ff_thread_finish_setup

(

AVCodecContext *

avctx

)

If the codec defines update_thread_context(), call this when they are ready for the next thread to start decoding the next frame.

After calling it, do not change any variables read by the update_thread_context() method, or call ff_thread_get_buffer().

Parameters

avctx

The context.

ff_thread_flush()

void ff_thread_flush

(

AVCodecContext *

avctx

)

Wait for decoding threads to finish and reset internal state.

Called by avcodec_flush_buffers().

Parameters

avctx

The context.

ff_thread_get_buffer()

int ff_thread_get_buffer	(	AVCodecContext *	avctx,
		ThreadFrame *	f,
		int	flags
	)

Wrapper around get_buffer() for frame-multithreaded codecs.

Call this function instead of ff_get_buffer(f). Cannot be called after the codec has called ff_thread_finish_setup().

Parameters

avctx	The current context.
f	The frame to write into.

ff_thread_get_format()

enum AVPixelFormat ff_thread_get_format	(	AVCodecContext *	avctx,
		const enum AVPixelFormat *	fmt
	)

Wrapper around get_format() for frame-multithreaded codecs.

Call this function instead of avctx->get_format(). Cannot be called after the codec has called ff_thread_finish_setup().

Parameters

avctx	The current context.
fmt	The list of available formats.

ff_thread_release_buffer()

void ff_thread_release_buffer	(	AVCodecContext *	avctx,
		ThreadFrame *	f
	)

Wrapper around release_buffer() frame-for multithreaded codecs.

Call this function instead of avctx->release_buffer(f). The AVFrame will be copied and the actual release_buffer() call will be performed later. The contents of data pointed to by the AVFrame should not be changed until ff_thread_get_buffer() is called on it.

Parameters

avctx	The current context.
f	The picture being released.

ff_thread_report_progress()

void ff_thread_report_progress	(	ThreadFrame *	f,
		int	progress,
		int	field
	)

Notify later decoding threads when part of their reference picture is ready.

Call this when some part of the picture is finished decoding. Later calls with lower values of progress have no effect.

Parameters

f	The picture being decoded.
progress	Value, in arbitrary units, of how much of the picture has decoded.
field	The field being decoded, for field-picture codecs. 0 for top field or frame pictures, 1 for bottom field.