| 1 | /* |
| 2 | * Copyright (c) 2004 Roman Shaposhnik |
| 3 | * Copyright (c) 2008 Alexander Strange (astrange@ithinksw.com) |
| 4 | * |
| 5 | * Many thanks to Steven M. Schultz for providing clever ideas and |
| 6 | * to Michael Niedermayer <michaelni@gmx.at> for writing initial |
| 7 | * implementation. |
| 8 | * |
| 9 | * This file is part of FFmpeg. |
| 10 | * |
| 11 | * FFmpeg is free software; you can redistribute it and/or |
| 12 | * modify it under the terms of the GNU Lesser General Public |
| 13 | * License as published by the Free Software Foundation; either |
| 14 | * version 2.1 of the License, or (at your option) any later version. |
| 15 | * |
| 16 | * FFmpeg is distributed in the hope that it will be useful, |
| 17 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 19 | * Lesser General Public License for more details. |
| 20 | * |
| 21 | * You should have received a copy of the GNU Lesser General Public |
| 22 | * License along with FFmpeg; if not, write to the Free Software |
| 23 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 24 | */ |
| 25 | |
| 26 | /** |
| 27 | * @file |
| 28 | * Multithreading support functions |
| 29 | * @see doc/multithreading.txt |
| 30 | */ |
| 31 | |
| 32 | #include "avcodec.h" |
| 33 | #include "internal.h" |
| 34 | #include "pthread_internal.h" |
| 35 | #include "thread.h" |
| 36 | |
| 37 | /** |
| 38 | * Set the threading algorithms used. |
| 39 | * |
| 40 | * Threading requires more than one thread. |
| 41 | * Frame threading requires entire frames to be passed to the codec, |
| 42 | * and introduces extra decoding delay, so is incompatible with low_delay. |
| 43 | * |
| 44 | * @param avctx The context. |
| 45 | */ |
| 46 | static void validate_thread_parameters(AVCodecContext *avctx) |
| 47 | { |
| 48 | int frame_threading_supported = (avctx->codec->capabilities & CODEC_CAP_FRAME_THREADS) |
| 49 | && !(avctx->flags & CODEC_FLAG_TRUNCATED) |
| 50 | && !(avctx->flags & CODEC_FLAG_LOW_DELAY) |
| 51 | && !(avctx->flags2 & CODEC_FLAG2_CHUNKS); |
| 52 | if (avctx->thread_count == 1) { |
| 53 | avctx->active_thread_type = 0; |
| 54 | } else if (frame_threading_supported && (avctx->thread_type & FF_THREAD_FRAME)) { |
| 55 | avctx->active_thread_type = FF_THREAD_FRAME; |
| 56 | } else if (avctx->codec->capabilities & CODEC_CAP_SLICE_THREADS && |
| 57 | avctx->thread_type & FF_THREAD_SLICE) { |
| 58 | avctx->active_thread_type = FF_THREAD_SLICE; |
| 59 | } else if (!(avctx->codec->capabilities & CODEC_CAP_AUTO_THREADS)) { |
| 60 | avctx->thread_count = 1; |
| 61 | avctx->active_thread_type = 0; |
| 62 | } |
| 63 | |
| 64 | if (avctx->thread_count > MAX_AUTO_THREADS) |
| 65 | av_log(avctx, AV_LOG_WARNING, |
| 66 | "Application has requested %d threads. Using a thread count greater than %d is not recommended.\n", |
| 67 | avctx->thread_count, MAX_AUTO_THREADS); |
| 68 | } |
| 69 | |
| 70 | int ff_thread_init(AVCodecContext *avctx) |
| 71 | { |
| 72 | validate_thread_parameters(avctx); |
| 73 | |
| 74 | if (avctx->active_thread_type&FF_THREAD_SLICE) |
| 75 | return ff_slice_thread_init(avctx); |
| 76 | else if (avctx->active_thread_type&FF_THREAD_FRAME) |
| 77 | return ff_frame_thread_init(avctx); |
| 78 | |
| 79 | return 0; |
| 80 | } |
| 81 | |
| 82 | void ff_thread_free(AVCodecContext *avctx) |
| 83 | { |
| 84 | if (avctx->active_thread_type&FF_THREAD_FRAME) |
| 85 | ff_frame_thread_free(avctx, avctx->thread_count); |
| 86 | else |
| 87 | ff_slice_thread_free(avctx); |
| 88 | } |