libavcodec/thread.h

   1 /*
   2  * Copyright (c) 2008 Alexander Strange <astrange@ithinksw.com>
   3  *
   4  * This file is part of Libav.
   5  *
   6  * Libav is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * Libav is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with Libav; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 /**
  22  * @file
  23  * Multithreading support functions
  24  * @author Alexander Strange <astrange@ithinksw.com>
  25  */
  26
  27 #ifndef AVCODEC_THREAD_H
  28 #define AVCODEC_THREAD_H
  29
  30 #include "config.h"
  31 #include "avcodec.h"
  32
  33 /**
  34  * Wait for decoding threads to finish and reset internal state.
  35  * Called by avcodec_flush_buffers().
  36  *
  37  * @param avctx The context.
  38  */
  39 void ff_thread_flush(AVCodecContext *avctx);
  40
  41 /**
  42  * Submit a new frame to a decoding thread.
  43  * Returns the next available frame in picture. *got_picture_ptr
  44  * will be 0 if none is available.
  45  * The return value on success is the size of the consumed packet for
  46  * compatibility with avcodec_decode_video2(). This means the decoder
  47  * has to consume the full packet.
  48  *
  49  * Parameters are the same as avcodec_decode_video2().
  50  */
  51 int ff_thread_decode_frame(AVCodecContext *avctx, AVFrame *picture,
  52                            int *got_picture_ptr, AVPacket *avpkt);
  53
  54 /**
  55  * If the codec defines update_thread_context(), call this
  56  * when they are ready for the next thread to start decoding
  57  * the next frame. After calling it, do not change any variables
  58  * read by the update_thread_context() method, or call ff_thread_get_buffer().
  59  *
  60  * @param avctx The context.
  61  */
  62 void ff_thread_finish_setup(AVCodecContext *avctx);
  63
  64 /**
  65  * Notify later decoding threads when part of their reference picture is ready.
  66  * Call this when some part of the picture is finished decoding.
  67  * Later calls with lower values of progress have no effect.
  68  *
  69  * @param f The picture being decoded.
  70  * @param progress Value, in arbitrary units, of how much of the picture has decoded.
  71  * @param field The field being decoded, for field-picture codecs.
  72  * 0 for top field or frame pictures, 1 for bottom field.
  73  */
  74 void ff_thread_report_progress(AVFrame *f, int progress, int field);
  75
  76 /**
  77  * Wait for earlier decoding threads to finish reference pictures.
  78  * Call this before accessing some part of a picture, with a given
  79  * value for progress, and it will return after the responsible decoding
  80  * thread calls ff_thread_report_progress() with the same or
  81  * higher value for progress.
  82  *
  83  * @param f The picture being referenced.
  84  * @param progress Value, in arbitrary units, to wait for.
  85  * @param field The field being referenced, for field-picture codecs.
  86  * 0 for top field or frame pictures, 1 for bottom field.
  87  */
  88 void ff_thread_await_progress(AVFrame *f, int progress, int field);
  89
  90 /**
  91  * Wrapper around get_buffer() for frame-multithreaded codecs.
  92  * Call this function instead of ff_get_buffer(f).
  93  * Cannot be called after the codec has called ff_thread_finish_setup().
  94  *
  95  * @param avctx The current context.
  96  * @param f The frame to write into.
  97  */
  98 int ff_thread_get_buffer(AVCodecContext *avctx, AVFrame *f);
  99
 100 /**
 101  * Wrapper around release_buffer() frame-for multithreaded codecs.
 102  * Call this function instead of avctx->release_buffer(f).
 103  * The AVFrame will be copied and the actual release_buffer() call
 104  * will be performed later. The contents of data pointed to by the
 105  * AVFrame should not be changed until ff_thread_get_buffer() is called
 106  * on it.
 107  *
 108  * @param avctx The current context.
 109  * @param f The picture being released.
 110  */
 111 void ff_thread_release_buffer(AVCodecContext *avctx, AVFrame *f);
 112
 113 int ff_thread_init(AVCodecContext *s);
 114 void ff_thread_free(AVCodecContext *s);
 115
 116 #endif /* AVCODEC_THREAD_H */